Nevado del Ruiz

The Nevado del Ruiz (), also known as La Mesa de Herveo () is a volcano on the border of the departments of Caldas and Tolima in Colombia, about west of the capital city Bogotá. It is a stratovolcano composed of many layers of lava alternating with hardened volcanic ash and other pyroclastic rocks. Volcanic activity at Nevado del Ruiz began about two million years ago, since the Early Pleistocene or Late Pliocene, with three major eruptive periods. The current volcanic cone formed during the present eruptive period, which began 150,000 years ago.
The volcano usually generates Vulcanian to Plinian eruptions, which produce swift-moving currents of hot gas and rock called pyroclastic flows. These eruptions often cause massive lahars (mud and debris flows), which pose a threat to human life and the environment. The impact of such an eruption is increased as the hot gas and lava melt the mountain's snowcap, adding large quantities of water to the flow. On November 13, 1985, a small eruption produced an enormous lahar that buried and destroyed the town of Armero in Tolima, causing an estimated 25,000 deaths. This event later became known as the Armero tragedy—the deadliest lahar in recorded history. Similar but less deadly incidents occurred in 1595 and 1845, consisting of a small explosive eruption followed by a large lahar.
The volcano is part of Los Nevados National Natural Park, which also contains several other volcanoes. The summit of Nevado del Ruiz is covered by large glaciers. The volcano continues to pose a threat to the nearby towns and villages, and it is estimated that up to 500,000 people could be at risk from lahars from future eruptions.
Today, the Nevado del Ruiz volcano is constantly monitored by the Volcanic and Seismic Observatory of Manizales.
Geography and geology.
Nevado del Ruiz, which lies about west of Bogotá, is part of the Andes mountain range. The volcano is part of the Ruiz–Tolima volcanic massif (or Cordillera Central), a group of five ice-capped volcanoes which also includes the Tolima, Santa Isabel, Quindio and Machin volcanoes. The massif is located at the intersection of four faults, some of which still are active.
Nevado del Ruiz lies within the Pacific Ring of Fire, a region that encircles the Pacific Ocean and contains some of the world's most active volcanoes. It is the third most northernly of the volcanoes lying in the North Volcanic Zone of the Andean Volcanic Belt, which contains 75 of the 204 Holocene-age volcanoes in South America. The Andean Volcanic Belt is produced by the eastward subduction of the oceanic Nazca Plate beneath the South American continental plate. As is the case for many subduction-zone volcanoes, Nevado del Ruiz can generate explosive Plinian eruptions with associated pyroclastic flows that can melt snow and glaciers near the summit, producing large and sometimes devastating lahars (mud and debris flows).
Like many other Andean volcanoes, Nevado del Ruiz is a stratovolcano: a voluminous, roughly conical volcano consisting of many strata of hardened lava and tephra including volcanic ash. Its lavas are andesitic–dacitic in composition. The modern volcanic cone comprises five lava domes, all constructed within the caldera of an ancestral Ruiz volcano: Nevado El Cisne, Alto de la Laguna, La Olleta, Alto la Pirana, and Alto de Santano. It covers an area of more than , stretching from east to west. The mountain's broad summit includes the Arenas crater, which is in diameter and deep. Nevado del Ruiz, as its neighbours to the southwest Nevado El Cisne and Nevado de Santa Isabel is located over the Palestina Fault that crosscuts the underlying El Bosque Batholith, dated at 49.1 ± 1.7 Ma.
The summit of the volcano has steep slopes inclining from 20 to 30 degrees. At lower elevations, the slopes become less steep; their inclination is about 10 degrees. From there on, foothills stretch almost to the edge of the Magdalena River, north of the volcano and the Cauca River to the west. On the two major sides of the summit, headwalls show where past rock avalanches occurred. At times, ice on the summit has melted, generating devastating lahars, including the continent's deadliest eruption in 1985. On the volcano's southwest flank is the pyroclastic cone La Olleta, which is not currently active, but may have erupted in historical times.
Glaciers.
The summit of Nevado del Ruiz is covered by glaciers ("nevado" means "snow-covered" in Spanish), which formed over many thousands of years, and have generally retreated since the last glacial maximum. From 28,000 to 21,000 years ago, glaciers occupied about of the Ruiz–Tolima massif. As late as 12,000 years ago, when the ice sheets from the last glacial period were retreating, they still covered . During the Little Ice Age, which lasted from about 1600 to 1900 CE, the ice cap covered approximately .
Since then the glaciers have retreated further because of atmospheric warming. By 1959, the massif's glaciated area had dropped to . Since the 1985 eruption, which destroyed about 10% of the summit ice cover, the area of Nevado del Ruiz covered by glaciers has halved—from just after the eruption to about in 2003. The glaciers reached altitudes as low as in 1985 but have now retreated to elevations of .
The ice cap is approximately thick on average. It is thickest in parts of the summit plateau and under the Nereides Glacier on the southwestern slopes, where it is as deep as . Glaciers on the northern and, to a lesser extent, the eastern slopes lost the most ice in the 1985 eruption, and therefore reach only up to deep. The deep ice covering the summit plateau may hide a caldera. Five domes ringing the summit plateau have emerged as the ice has retreated.
The meltwater from the glaciers drains primarily to the Cauca River and Magdalena River via the western and eastern flanks of the volcano, respectively. Runoff from these glaciers and those on the surrounding volcanoes is a source of fresh water for forty surrounding towns, and Colombian scientists and government officials are concerned about the towns' water supply should the glaciers melt completely.
Flora and fauna.
Nevado del Ruiz is generally poorly forested because of its high elevation, and its forest cover decreases with increasing elevation. At lower elevations, well-developed mesic forests (20–35 meters / 66–110 ft high) are present. Above these but below the tree line, parts of the volcano are covered with dwarf forests high. Above the tree line, in the Páramo zone, the vegetation is dominated by plants such as bunchgrass and Espeletia. Regional vegetation consists of different families of woody plants, including Rubiaceae, Leguminosae, Melastomataceae, Lauraceae, and Moraceae. Flowers such as "Polypodiaceae s.l.", Araceae, Poaceae, Asteraceae, Piperaceae, and Orchidaceae are also present in the region.
Animals living on the volcano include the mountain tapir and spectacled bear, both of which are designated as threatened. Other animals inhabiting the surrounding region include the rufous-fronted parakeet, bearded helmetcrest, and Herveo plump toad. The volcano is home to 27 species of birds endemic to Colombia, with 14 of these species confined to the region around the volcano. 15 bird species in the area are considered threatened.
Los Nevados National Park.
Nevado del Ruiz is one of several stratovolcanoes within Los Nevados National Natural Park, a national park located west of Bogotá in the centre of the Colombian Andes. The park is a popular tourist destination and contains several tourist shelters. The slopes of the volcano are used for winter sports, and nearby Lake Otún offers trout fishing. A number of commercially operated spas can be found nearby.
In 1868–1869, German geologists Wilhelm Reiss and Alphons Stübel were the first to attempt to climb Ruiz. In 1936, W. Cunet and Augusto Gansser-Biaggi made the first successful ascent, partly by ski; they repeated the ascent in 1939.
Eruptive history.
The first eruptions of Nevado del Ruiz occurred about 1.8 million years ago at the beginning of the Pleistocene epoch. Three primary eruption periods in the history of the massif have been identified: "ancestral", "older" and "present". During the "ancestral" period between one million to two million years ago, a complex of large stratovolcanoes was created. Between 1.0 million and 0.8 million years ago, they partially collapsed, forming large (5–10 km wide) calderas. During the "older" period, which lasted from 0.8 million to 0.2 million years ago, a new complex of large stratovolcanoes developed (including Older Ruiz, Tolima, Quindio, and Santa Isabel). Once again explosive summit calderas formed from 0.2 million to 0.15 million years ago.
The "present" period began about 150,000 years ago and involved the development of the present volcanic edifice through the emplacement of lava domes made of andesite and dacite (igneous rocks) inside older calderas. During the past 11,000 years, Nevado del Ruiz passed through at least 12 eruption stages, which included multiple slope failures (rock avalanches), pyroclastic flows and lahars leading to partial destruction of the summit domes. During the past several thousand years, eruptions of the volcanoes in the Ruiz–Tolima massif have mostly been small, and the pyroclastic flow deposits have been much less voluminous than during the Pleistocene. Since the volcano's earlier eruptions are not recorded, volcanologists have used tephrochronology to date them.
During recorded history, eruptions have consisted primarily of a central vent eruption (in the caldera) followed by an explosive eruption, then lahars. Ruiz's earliest identified Holocene eruption was about 6660 BC, and further eruptions occurred in 1245 BC ± 150 years (dated through radiocarbon dating), about 850 BC, 200 BC ± 100 years, 350 AD ± 300 years, 675 AD ± 50 years, in 1350, 1541 (perhaps), 1570, 1595, 1623, 1805, 1826, 1828 (perhaps), 1829, 1831, 1833 (perhaps), 1845, 1916, December 1984 – March 1985, September 1985 – July 1991, and possibly in April 1994. Many of these eruptions involved a central vent eruption, a flank vent eruption, and a phreatic (steam) explosion. Ruiz is the second-most active volcano in Colombia after Galeras.
1595 lahar.
On November 13, 1595, Nevado del Ruiz erupted. The episode consisted of three Plinian eruptions, which were heard up to from the summit of the volcano. A large amount of ash was ejected, which completely darkened the surrounding area. The volcano also erupted lapilli (a form of tephra) and pumice bombs. In total, the eruption produced 0.16 km3 of tephra. The eruption was preceded by a large precursor earthquake three days before. The eruption caused lahars, which traveled down the valleys of the nearby Gualí and Lagunillas rivers, clogging up the water, killing fish and destroying vegetation. More than 600 people died as a result of the lahar. The 1595 eruption was the last major eruption of Nevado del Ruiz before 1985. The 1595 and 1985 eruptions were similar in many respects, including in the chemical composition of the erupted material.
1845 lahar.
On the morning of February 19, 1845, a large earthquake resulted in a substantial mudflow. This mudflow flowed down the valley of the Lagunillas River for approximately , spilling out of the river channel and killing much of the local population. After reaching an alluvial fan, the mudflow split into two branches. The larger portion of it joined the Lagunillas River and flowed into the nearby Magdalena River, while the smaller portion was diverted by hills in front of Lagunillas Canyon, turned 90 degrees to the north until it reached the Sabandija River, and then flowed east with the Sabandija River, until it rejoined the other branch of the mudflow at the junction of the Sabandija and the Magdalena. It is estimated that 1000 people were killed in the mudflows.
Eruption (1985).
Beginning November 1984, geologists observed an increasing level of seismic activity near Nevado del Ruiz. Such volcanic tectonic seismicity is often a precursor of an upcoming eruption. Other signs of a forthcoming eruption included increased fumarole activity, deposition of sulfur on the summit of the volcano, and small phreatic eruptions. In the latter, hot magma came in contact with water, resulting in explosions as the water was almost instantly turned into steam. The most notable of these events was an ash ejection on September 11, 1985. The activity of the volcano decreased in October 1985. The most likely explanation of the events is that new magma rose into the volcanic edifice before September 1985.
An Italian volcanological mission analyzed gas samples from fumaroles along the Arenas crater floor and proved them to be a mixture of carbon dioxide and sulfur dioxide, indicating a direct release of magma into the surface environment. The mission's report, delivered on October 22, 1985, judged the risk of lahars to be very high. The report proposed various simple preparedness techniques to local authorities.
In November 1985, volcanic activity once again increased as magma neared the surface. The volcano began releasing increasing quantities of gases rich in sulfur dioxide and elementary sulfur. The water content of the fumaroles' gases decreased, and water springs in the vicinity of Nevado del Ruiz became enriched in magnesium, calcium and potassium, which were leached from the magma. The thermodynamic equilibration (stationary heat energy) temperatures, corresponding to the chemical composition of the discharged gases, were from to . The extensive degassing of the magma caused pressure to build up inside the volcano, which eventually resulted in the explosive eruption.
Eruption and lahars.
At 3:06 pm, on November 13, 1985, Nevado del Ruiz began to erupt, ejecting dacitic tephra more than into the atmosphere. The total mass of the erupted material (including magma) was 35 million tonnes—only 3% of the amount that erupted from Mount St. Helens in 1980. The eruption reached a value of 3 on the Volcanic Explosivity Index. The mass of the ejected sulfur dioxide was about 700,000 tonnes, or about 2% of the mass of the erupted solid material, making the eruption atypically sulfur-rich.
The eruption produced pyroclastic flows that melted summit glaciers and snow, generating four thick lahars that raced down river valleys on the volcano's flanks. It also destroyed a small lake that was observed in Arenas crater several months before the eruption. Water in such volcanic lakes tends to be extremely salty and contain dissolved volcanic gases. The lake's hot, acidic water significantly accelerated the melting of the ice; this effect was confirmed by the large amounts of sulfates and chlorides found in the lahar flow.
The lahars, formed of water, ice, pumice, and other rocks, mixed with clay as they travelled down the volcano's flanks. They ran down the volcano's sides at an average speed of 60 km per hour, eroding soil, dislodging rock, and destroying vegetation. After descending thousands of meters down the side of the volcano, the lahars were directed into all of the six river valleys leading from the volcano. While in the river valleys, the lahars grew to almost 4 times their original volume. In the Gualí River, a lahar reached a maximum width of .
One of the lahars virtually erased the town of Armero in Tolima, which lay in the Lagunilla River valley. Only one quarter of its 28,700 inhabitants survived. The second lahar, which descended through the valley of Chinchiná River, killed about 1,800 people and destroyed about 400 homes in the town of Chinchiná, in the department of Caldas. In total, over 23,000 people were killed and approximately 5,000 were injured. More than 5,000 homes were destroyed. The Armero tragedy, as the event came to be known, was the second-deadliest volcanic disaster in the 20th century, being surpassed only by the 1902 eruption of Mount Pelée, and is the fourth-deadliest volcanic eruption in recorded history. It is also the deadliest known lahar, and Colombia's worst natural disaster. A young girl named Omayra Sánchez became a worldwide symbol of the disaster after images of her trapped under the debris of her former home, after the eruption made the news worldwide.
The loss of life during the 1985 eruption was due partly to the fact that scientists did not know precisely when the eruption would occur, and the authorities would not take costly preventive measures without clear warnings of imminent danger. Because the volcano's last substantial eruption occurred more than 140 years earlier, it was also hard for many to accept the danger the volcano presented; locals even called it the "Sleeping Lion". Hazard maps showing Armero would be completely flooded after an eruption were distributed more than a month before the eruption, but the Colombian Congress criticized the scientific and civil defense agencies for scaremongering. Local authorities failed to alert people to the seriousness of the situation, with Armero's mayor and a priest both reassuring the populace after an ash eruption on the afternoon of November 13 and the consequent ashfall early that evening. Another factor was the storm that hit that evening, causing electrical outages and hindering communications. Civil defense officials from four nearby towns tried to warn Armero the lahar was approaching in the hour or so before it reached Armero, but failed to make radio contact.
Scientists later looked back to the hours before the eruption and noticed that several long-period earthquakes, which start out strong and then slowly die out, had occurred in the final hours before the eruption. Volcanologist Bernard Chouet said that, "the volcano was screaming 'I'm about to explode'", but the scientists who were studying the volcano at the time of the eruption were not able to read this signal.
Current threats and preparedness.
The volcano continues to pose a serious threat to nearby towns and villages. The most likely hazard is small-volume eruptions, which might destabilize glaciers and trigger lahars. Despite the significant retrenchment of the volcano's glaciers, the volume of ice atop Nevado del Ruiz and other volcanoes in the Ruiz–Tolima massif remains large. Melting merely 10% of the ice would produce mudflows with a volume of up to —similar to the mudflow that destroyed Armero in 1985. Such lahars can travel up to along river valleys in a matter of few hours. Estimates show that up to 500,000 people living in the Combeima, Chinchiná, Coello-Toche, and Guali valleys are in danger, and 100,000 of these are considered to be at high risk. Lahars pose a threat to nearby towns of Honda, Mariquita, Ambalema, Chinchiná, Herveo, Villa Hermosa, Salgar and La Dorada. Although small eruptions are more likely, the two million-year eruptive history of the Ruiz–Tolima massif includes numerous large eruptions, indicating that the threat of a large eruption cannot be ignored.
A large eruption would have more widespread effects, including the potential closure of Bogotá's airport due to ashfall.
As the Armero tragedy was exacerbated by the lack of early warnings, unwise land use, and the unpreparedness of nearby communities, the government of Colombia created a special program ("Oficina Nacional para la Atencion de Desastres", 1987) to prevent such incidents in the future. All Colombian cities were directed to promote prevention planning in order to mitigate the consequences of natural disasters, and evacuations due to volcanic hazards have been carried out. About 2,300 people living along five nearby rivers were evacuated when Nevado del Ruiz erupted again in 1989. When another Colombian volcano, the Nevado del Huila, erupted in April 2008, thousands of people were evacuated because volcanologists worried that the eruption could be another "Nevado del Ruiz".
In 2006, heavy rains on Ruiz sent a mudslide down the Chinchiná River, killing nine youths aged 12–19 on a scouting expedition near the volcano.
Recent activity.
During September and October 2019, INGEOMINAS (Colombian Institute of Mining and Geology) noted gradual increases in seismic activity near the Arenas crater. Sulfurous odors and phreatic eruptions reported at Nevado del Ruiz prompted an alert level of Yellow on October 1. Chemical analysis of the volcano demonstrated deformative changes and geochemical alterations. Over the next four months a smattering of long-period earthquakes, considered pseudo-Tornillo events, raised worries that the volcano might erupt. In 2010, tilt increased, and on average 890 volcanic tremors were recorded monthly, roughly eight times as many as had been recorded from 2009 to 2010.
Scientists flying over the volcano on March 8, 2012 noted fresh ash deposits on the east flank of the volcano near the crater, likely from an phreatic eruption on February 22. Later that day, a small ash plume erupted from the crater; by March 13, scientists detected ash deposits at the head of the Gualí River. After seismicity continued to increase, the alert level was raised to Orange, and in April Nevados National Natural Park authority closed the reserve, fearing lahars and ashfall hazards. The sudden activity peak in March did not culminate in a major eruption, and activity declined enough that the alert level was lowered to Yellow on May 3. On May 29, seismicity rapidly increased, and the alert level was restored to Orange because ash fell into more than 20 nearby communities. Over the next few months ash fell frequently until earthquakes increased again in June. Because of the severity of these tremors, evacuations were ordered by the Emergency Committee of Caldas on news media for 300–1500 people near the volcano. The alert level was raised to Red, indicating an imminent major volcanic event, and an eruption in diameter took place on July 2, 2012, continuing intermittently until the end of August. Ash plumes and sulfur dioxide emissions recurred until January 2013.
Through the beginning of July 2013, ashfall took place at Nevado del Ruiz a few times per month. On July 11, 2013, there was a relatively large explosion, followed by inactivity until August, when emission of ash resumed, continuing intermittently until April 2014. Reports of ashfall stopped until October 2014. In November 2014, earthquakes were recorded, and volcanic ash was observed near the summit; ashfall reached local communities within a radius of Nevado del Ruiz multiple times each month until December 2015. A lava dome was extruded from August to the end of October in 2015, coinciding with thermal anomalies increasing near the summit crater at the end of the same year. According to the Global Volcanism Program, the last documented eruption at Nevado del Ruiz took place in 2017. However, reports from the Servicio Geológico Colombiano observatory at Manizales through the end of October 2018 suggested earthquakes near the volcano, with phreatic eruptions ejecting water vapor, volcanic ash, and volcanic gases up to over its crater.


Giuseppe Seguenza

Giuseppe Seguenza (Messina, June 8, 1833 – Messina, February 3, 1889) was an Italian naturalist and geologist.
Early life.
Giuseppe Seguenza was born on June 8, 1833, in Italy. Because his father expected him to follow in his footsteps and become a pharmacist, Seguenza studied under his father, who also owned his own pharmacy.
Later, Seguenza has chose to study the geological and mineralogical sciences.
Scientific research.
At the age of 23, Giuseppe Seguenza discovered that all the products of the emanations of Vulcano (one of the Aeolian Islands) contained arsenic compounds. Afterward, he published other scientific works that earned him the attention of scholars in Europe and the silver medal at the Paris Exposition.
He was appointed Professor of Natural History at the Maurolico School, then the Technical Institute of Messina, and finally earned a professorship at the University of Messina.
There followed other work around the metalliferous deposits of Fiumedinisi, land and fossils of the territory of Messina, and Calabria, which were awarded and published at his own expense by the Royal Academy of the Lincei.
In 1868 he introduced the Zanclean stage to define the early part of the Pliocene. A genus of sea snails, known as "Seguenzia" (family Seguenziidae), was named in his honor.
Family and legacy.
Giuseppe Seguenza died at the age of 58 and his son, Luigi Seguenza, continued forward his work. Luigi is known for having defined the taxonomy for "Calliotropis", a genus of sea snails.
One of the three science high schools in Messina, "Liceo Scientifico G. Seguenza", is named after Giuseppe. The museum of modern people of "Nizza di Sicilia" is also dedicated to him.


Prochelidella

Prochelidella is an extinct genus of Early to Late Cretaceous chelid turtles from the Bajo Barreal, Candeleros, Cerro Barcino and Portezuelo Formations of the Cañadón Asfalto, Golfo San Jorge and Neuquén Basins in Patagonia, Argentina. It includes the following species:


Palaeoamyda

Palaeoamyda is an extinct genus of softshell turtle belonging to the family Trionychidae. Remains have been found in the Eocene of Germany.
Taxonomy.
Karl (1998) considered "Palaeoamyda" a synonym of "Rafetoides austriacus" (Peters, 1858), but subsequent re-description of the material showed that it was a distinct genus in its own right.
Description.
"Palaeoamyda" is a three-clawed soft-shell turtle that can reach a length of about two feet. It is the largest species of turtles of Messel Pit Fossil Site. The carapace and plastron are not connected by bony prominences and the plastron shows bony plates reduced to small protrusions.


Tectonic evolution of the Barberton greenstone belt

The Barberton greenstone belt (BGB) is located in the Kapvaal craton of southeastern Africa. It characterizes one of the most well-preserved and oldest pieces of continental crust today by containing rocks in the Barberton Granite Greenstone Terrain (3.55–3.22 Ga). The BGB is a small, cusp-shaped succession of volcanic and sedimentary rocks, surrounded on all sides by granitoid plutons which range in age from >3547 to <3225 Ma. It is commonly known as the type locality of the ultramafic, extrusive volcanic rock, the komatiite. Greenstone belts are geologic regions generally composed of mafic to ultramafic volcanic sequences that have undergone metamorphism. These belts are associated with sedimentary rocks that occur within Archean and Proterozoic cratons between granitic bodies. Their name is derived from the green hue that comes from the metamorphic minerals associated with the mafic rocks. These regions are theorized to have formed at ancient oceanic spreading centers and island arcs. In simple terms, greenstone belts are described as metamorphosed volcanic belts. Being one of the few most well-preserved Archean portions of the crust, with Archean felsic volcanic rocks, the BGB is well studied. It provides present geologic evidence of Earth during the Archean (pre-3.0 Ga). Despite the BGB being a well studied area, its tectonic evolution has been the cause of much debate.
General geology of the BGB.
The BGB is contained within part of a larger system called the Barberton Granite Greenstone Terrain (BGGT) which includes two main components; the supracrustal succession, which defines the BGB portion, and the deeper-level intrusive units that surround the BGB. Major rock types found within the BGB are mafic to ultramafic volcanics, sedimentary, and shallow intrusive rocks covered by a thin sedimentary veneer. The deeper-level intrusive pluton units dome up under the greenstone belt and are divided into two major groups: the TTG group, (tonalite-trondhjemite-granodiorite) which consists of plagioclase dominant feldspar minerals and the GMS group (granite-monzonite-syenite), in which alkali feldspars are the dominant mineral composition. Pre-3.2 Ga, eruptions of mafic to ultramafic volcanics formed thick sequences. Following the formation of the thick volcanic layers was cyclic deposition of volcanic and sedimentary rocks. Then intrusions of plutonic TTG bodies began the formation of dome-and-keel structures. The volcanic layers deformed into synclines and the dome like TTG bodies created anticlines which is represented in the BGB today.
Stratigraphy.
The BGB consists of locally derived sediments and chemical sediments, but is composed mostly of TTGs and greenstones, as briefly discussed above. Three main lithostratigraphic units are used to divide the BGB. The base contains the Onverwacht, followed by the Fig Tree, and the topmost Moodies Groups. The Onverwacht Group is composed largely of mafic and ultramafic volcanics. Thin interbedded sedimentary units that have silicified into impure chert mark breaks that have resulted from eruptive activity. This group ranges in age from >3547 to ~3260 Ma and is over 10 km thick. The Fig Tree Group was deposited between ~3260 and 3225 Ma. It is defined as a transitional unit of interlayered volcanic clasts and land derived sediments that were eroded from the underlying greenstone succession. The Moodies Group, post-3225 Ma, is a combination of sandstone and conglomerate originating from the erosion of the underlying greenstone unit and the uplifted plutonic rocks.
Structure.
The structural pattern within the region shows a series of anticlines and synclines that plunge towards the core of the belt. Synclines are the dominant folding structure within the region. However, there is a major anticline, called the Onverwacht Anticline, located in the central portion of the BGB. Granite-greenstone terrains are characterized by broad domiform TTG bodies underlying tight synclinal basalts and komatiites. This common structure associated with greenstone belts is called a 'dome-and-keel' structure (shown to the right). The formation of this particular structure is not yet fully understood but there are numerous models that attempt to explain it as well as the overall evolution of the greenstone belt.
Models.
The tectonic evolution of the BGB is a common source of controversy within the scientific community. Being a well-preserved piece of old continental crust, the observed kinematics, structures and mineralogy within the BGB have been well studied. Although the area is well studied, the understanding as to how these structures came to be is still uncertain. Numerous models, derived from geologic modeling, have been generated in an attempt to piece together the extensive tectonic evolution of the BGB. The following sections are a limited representation of current models which provide possible explanations for the formation of the BGB.
Accretion.
This model functions under the assumption that Archean tectonics were similar to present day plate tectonics. It claims the BGB is a result of multiple events involving a subduction-like environment followed by arc processes causing arc amalgamation. In this setting, terrains converge onto an immobile craton and reflect sequential stacking. This accretion-like convergent process is thought to have occurred ~3.23 Ga. Some interpretations of this model involve the presence of oceanic crust originating from subduction accretion of crust in a collision arc setting. Other interpretations involving accretion present tectonic amalgamation and suturing of pre-existing bodies to form a larger continental block.
Convective overturn.
Also called "vertical tectonics" because structures move vertically due to gravity-driven instabilities. The deformation that occurs within the greenstone belts represents a dome-and-keel structure or the rise of diapiric plutons. This model provides an explanation for the dome-and-keel structure associated with greenstone belts. When dense basaltic lavas erupt on top of ductile, less dense TTGs they become weighed down by the overburden and squeeze out from areas with less stress. Partial convective overturn is a related idea stating that a thick, dense, cool greenstone cover in the upper crust acts as an insulator to the underlying hot granitic middle crust. Previously metamorphosed dense amphibolites at the base of the overlying greenstone layer sank down into a partially melted granitic middle crust. These sinking greenstones forced the granitic partial melts sideways and upwards, emplacing them into the margins of the belt and later folding them. The greenstone cover allows the granitic layer to remobilize and form the dome structure. This two stage event is dated between 3.26 and 3.22 Ga.
Importance.
The BGB provides an area that contains some of the oldest known rocks available to study. The importance of this geological setting lies in the ability to study and obtain a better understanding of geologic history. Using information from this area has provided direct geologic evidence on the nature and evolution of the Earth before 3.0 Ga. Evidence of early crust, ocean chemistry, biota and atmosphere can be derived from the BGB. Despite the large quantity and the variable explanations of the models, they are necessary to the development of scientific understanding.


Valdivian Coastal Range


Glaphyrorhynchus

Glaphyrorhynchus is an extinct genus of teleosaurid thalattosuchian from the Middle Jurassic (Aalenian) of southern Germany.
Taxonomy and provenance.
"Glaphyrorhynchus" is known only from a jaw fragment found in the late Aalenian of Aalen, Germany. The holotype is lost, so the validity of the taxon remains unclear.


Nardovelifer

Nardovelifer altipinnis is the oldest known lamprid fish. It dates from the Campanian age of Nardò, Italy.


Turnu oil field

The Turnu oil field is an oil field located in Pecica, Arad County. It was discovered in 1964 and developed by Petrom. It began production in 1965 and produces oil. The total proven reserves of the Turnu oil field are around 51 million barrels (7×106tonnes), and production is centered on .


Rudolf Kaufmann

Rudolf Kaufmann (3 April 1909 – c. 1941), son of the physicist Walter Kaufmann, was a palaeontologist and geologist, and is best remembered for his work on allopatric speciation and punctuated equilibrium in the trilobite genus "Olenus" in the Upper Cambrian of Sweden and on the island of Bornholm. He was a brother-in-law of Curt Teichert, the well-known German-American palaeontologist and geologist. Studying the Upper Cambrian alum shales in Sweden, Kaufmann found that the trilobite genus "Olenus" occurred in an unbroken sequence of sediments covering a considerable period of geological time. He was thereby in a position to track the phylogenetic evolution of "Olenus", that is, the rise and fall of species within the genus and the changes in their morphology. He coined the idea of "Artabwandlung", which is the tendency of clade elements in the same environment to show the same morphological trends.
With the 1930s onset of the Nazi regime in Germany, Kaufmann, who had Jewish roots, but had been baptised an evangelical Christian, was dismissed from his position at Greifswald University. He had studied at Königsberg and at Greifswald University under Serge von Bubnoff (1888–1957). His 1933 dissertation dealt with speciation and punctuated equilibrium in Cambrian trilobites in Skåne.
He left Germany for Copenhagen in 1933. Here he was denied employment as a geologist, and worked as a photographer and gave instruction in athletics. He found himself ill at ease in Denmark, and after a spell in Italy, returned to Gemany, where in October 1935 he started teaching at a Jewish school in Coburg, and was arrested on a charge of 'miscegenation' (he was being treated for a sexually transmitted disease acquired from a prostitute) and in 1936 sentenced to 3 years of hard labour. On his release in 1939 Kaufmann fled to Lithuania, where he was allowed to settle and resume geological work. When Lithuania became part of the U.S.S.R. in 1940 he joined the staff of the Geological Survey at Kaunas, immersing himself in the problems of Pleistocene drift, and marrying a fellow refugee. After the German occupation of Lithuania in 1941, and now an undesirable Jew, he was identified while cycling on a country road and executed by two German soldiers.
Earlier, in his search for work, he had moved to Italy and found work in a photographic shop in Bologna. There, in the summer of 1935 he met Ingeborg Magnusson, a 28-year-old Swedish woman on holiday. This relationship was to last five years, during which period they spent 13 days together - he visited her once in Stockholm, and she saw him once in Germany. These details came to light in 1991 when a German stamp collector bought a package of 30 letters, written by Kaufmann to Ingeborg, at a Frankfurt stamp auction.
Bibliography.
"Paper Kisses" - Reinhard Kaiser (Other Press, 2006)


Diunatans

Diunatans is an extinct genus of rorqual. It lived in the North Sea during the Early Pliocene. Two specimens have been found from the Netherlands. They were collected from the Kattendijk Formation in the province of Zeeland, which is Zanclean in age. "Diunatans" is considered to be a stem balaenopterid because it falls outside the "Balaenoptera"+"Megaptera" clade, which includes all living rorquals.
Its name means "long-distance swimmer", from the Latin "diu" meaning "long time" or "long distance", and "natans", meaning "swimming." The type species is "D. luctoretemergo", named after the motto of Zeeland, "Luctor et Emergo" (Latin for "I struggle and I emerge").
"Diunatans" was around the size of the living minke whale. Several distinguishing characteristics can be seen in the skull of "Diunatans", including a large occipital condyle and very small nasal bones compared to other rorquals. The tympanic bulla, which encapsulates the middle ear, is also large.
"Diunatans" is the only known fossil rorqual from the North Sea. Many other fossil rorquals have been described, but all are now considered nomina dubia. English paleontologist Richard Owen named "Balaenoptera definata", "B. emarginata", and "B. gibbosa" in 1844. In the late 19th century, Belgian paleontologist Pierre-Joseph van Beneden named "B. borealina", "B. musculoides", "B. rostratella", "B. sibbaldina", "Plesiocetus goropii", "Megapteropsis robusta", and "Megaptera affinus".


Ruhuhuaria

Ruhuhuaria is an extinct genus of owenettid procolophonoid reptile known from the Middle Triassic Manda Beds of southwestern Tanzania. "Ruhuhuaria" is known solely from the holotype CAMZM T997, poorly preserved but complete skull and mandible recently re-discovered in the collections of the Cambridge Museum of Zoology. It was collected by the English paleontologist Francis Rex Parrington in the early 1930s from the Lifua Member of Manda Beds of the Ruhuhu Basin in Songea Urban District of southwestern Tanzania, which dates back to the late Anisian stage of the Middle Triassic. "Ruhuhuaria" was first described and named by Linda Akiko Tsuji, Gabriela Sobral and Johannes Müller in 2013 and the type species is "Ruhuhuaria reiszi". The generic name is derived from the name of the Ruhuhu Basin. The specific name, "reiszi", honors the Canadian paleontologist Robert R. Reisz. Due to the poor preservation of the holotype, the phylogenetic position of "Ruhuhuaria" within Owenettidae is uncertain. "Ruhuhuaria" being the second youngest owenettid to date, supports the persistence of owenettids into the Middle Triassic and their coexistence with procolophonids.


Tragophylloceras

Tragophylloceras is an extinct genus of cephalopod belonging to the Ammonite subclass.
Distribution.
Jurassic of Austria, France, Germany, Serbia and Montenegro, Spain, Switzerland, Poland and the United Kingdom.


Crotalocephalides

Crotalocephalides is a genus of trilobites in the order Phacopida, that existed during the lower Devonian in what is now Germany. It was described by Alberti in 1967, and the type species is "Crotalocephalides gaertneri", which the author had originally described under the genus "Cheirurus" in 1962.
The type specimen was described from Ebersdorf, Upper Franconia.


Environmental Campus Birkenfeld

The Environmental Campus Birkenfeld (ECB) (German: "Umwelt-Campus Birkenfeld (UCB)") is a branch of the Hochschule Trier in the state of Rhineland-Palatinate, Germany. It is close to the small town of Birkenfeld in Rhineland-Palatinate, close to the border of Saarland, Luxembourg, Belgium and France. There are 2,500 students enrolled in two departments. There are a total of 59 professors teaching in both departments ( "Environmental Planning / Environmental Technology (Umweltplanung und -technik)" and "Environment Business / Environment Law (Umweltwirtschaft und -recht)").
Since the beginning of the academic year in October 2005, only bachelor and master students are being accepted as part of the Bologna process.
ECB is structured as a residential campus. It offers education, housing and employment all in one location (this is very rare in Germany). There are eight residential structures that provide housing for 777 students. As is characteristic of a university of applied sciences, the campus is structured so that the students have the opportunity to receive an early introduction to the sciences. Students are encouraged to take part in the research projects underway on campus. Some programs are even designed solely for student participation.
One such specialized project is the "traveling university". Students have the opportunity to travel to one of a selection of foreign countries to work on a project for a period of two weeks. Typical projects involve renewable energy sources and have been conducted in places as diverse as Opole (Poland) and Kunming (China). Similar future projects will be located in Brazil.
Incidentally, ECB is the only University in Germany that uses Renewable Energy Sources to generate heat.
History.
ECB has a very short history compared with other universities across the globe, however it is just as intriguing. The campus area was originally a US Army hospital that was built as a contingency in the event of a 3rd world war. Fortunately, it was never needed.
Near this location (Baumholder) was the 98th General Hospital, established in Neubrücke (a small town near Birkenfeld). The hospital had an area of 440,000 square metres when it opened in 1952. It had 1,000 beds as well as various medical specialty sections: Surgery, dental medicine, orthopedics, radiology, rehabilitation, eye medicine and others. The hospital was open through the 1970s and was closed in 1984 due to operational expenses.
In 1994 the US Army finally gave up on the hospital and by 1996 the complex was empty.
Environmental campus.
In 1996 the ECB was born. The first step was undertaken by the Landrat (county commissioner) of the Landkreis Birkenfeld (Birkenfeld County) Dr. Ernst Theilen. The academic founders were three professors; Prof. Dr. Michael Eulenstein, Prof. Dr.-Ing. Hanns Köhler and Prof. Dr. Marott Bronder. They offered the first courses taught at ECB.
At first, there was a lot of construction underway on campus. The final phase of construction (Central new building) was completed in 2000.
Study.
The attractive features of ECB are the modern methods of teaching, the small class sizes and the international contacts. There are now 2,500 students enrolled from beginning of winter semester 2005. There are 14 Bachelor, 4 Dual Bachelor and 12 Master's degree programs offered.
Bachelor.
degrees offered
The course of study for these degrees differ slightly from those offered in the United States, however, the German accreditation agency AQUAS will accept either.
Masters.
degrees offered
Research.
Although the environmental campus has only existed since 1996, it has already launched a set of institutes and competency centers built around the scientific curriculum.
Some of these are already internationally recognized.


Geology of Ethiopia

The geology of Ethiopia includes rocks of the Neoproterozoic East African Orogeny, Jurassic marine sediments and Quaternary rift-related volcanism. Events that greatly shaped Ethiopian geology is the assembly and break-up of Gondwana and the present-day rifting of Africa.
Rocks formed by the East African Orogeny 880 to 550 million years ago make up the oldest geological units in Ethiopia. The orogeny caused the closure of the ancient Mozambique Ocean. Rocks of Ethiopia formed concurrently with the Mozambique Belt and the Arabian-Nubian Shield forming a large north-south (predent-day coordinates) mountain chain called the Transgondwanan Supermountain. Erosion of this mountain may have played a role in triggering the Cambrian explosion. Erosion of the orogen and mountain was such that by the early Paleozoic a planation surface extended across Ethiopia. Sedimentary rocks of Ordovician age cover this surface making it largely an unconformity. At parts the unconformity of the Precambrian basement has glacial striations, rôche moutonnées and chatter marks formed likely during the Karoo Ice Age. The Paleozoic sedimentary cover above the unconformity is of fluvial and glacial origin (Enticho Sandstone, Edaga Arbi Glacials).
Early Jurassic marine sediments cover much of the older sediments including a planation surface of Triassic age. These sediments deposited as result of a regional marine transgression swept over the Horn of Africa during the initial break-up of Gondwana. Resultant rocks include sandstone, limestone, shale, marls and evaporites (Adigrat Sandstone, Antalo Limestone, Amba Aradam Formation). A third major plantion surface and uniformity formed in the following a tectonic event in the Early Cretaceous that tilted carbonates in the Tigray and Dire Dawa-Harar areas. On top of this surface lies a series a fluvial sediments. Depositions of marine sediments continued in eastern Ethiopia's Ogaden basin until the Eocene.
The Ethiopia-Yemen Continental Flood Basalts or Ethiopian traps that cover much of Ethiopia flowed over both irregular surfaces and peneplains preserving laterite soil beneath. The flood basalts covered initially a much larger area (>750,000 km2) just after eruption about 30 million years ago in the Oligocene with volumes reaching 350,000 km3 (Ashangi Basalts, Alaji Basalts). Since then erosion has reduced areal extent and volumes. The modern pattern of volcanism concentrated to the Afar Depression and the Main Ethiopian Rift begun in Late Miocene time. The area of modern volcanism contains the bulk of Ethiopias geothermal energy resources.


Arctolepis

Arctolepis is an extinct genus of placoderm fish, which lived during the Early Devonian period (408 – 307 million years ago). Fossils of "Arctolepis" have been found in what is now Norway and Michigan.


Pseudowaagenia

Pseudowaagenia is a genus of extinct ammonoid cephalopods in the family Aspidoceratidae.
Distribution.
Shells of this species have been found in the Jurassic of Italy and Madagascar.


Mapusaurus

Mapusaurus (meaning "Earth lizard") was a giant carcharodontosaurid carnosaurian dinosaur from the early Late Cretaceous (late Cenomanian to early Turonian stage), approximately 97 to 93 million years ago, of what is now Argentina and Chile.
Discovery.
"Mapusaurus" was excavated between 1997 and 2001, by the Argentinian-Canadian Dinosaur Project, from an exposure of the Huincul Formation (Rio Limay Subgroup, Cenomanian) at Cañadón del Gato. It was described and named by paleontologists Rodolfo Coria and Phil Currie in 2006.
The name "Mapusaurus" is derived from the Mapuche word "Mapu", meaning 'of the Land' or 'of the Earth' and the Greek "sauros", meaning 'lizard'. The type species, "Mapusaurus roseae", is named for both the rose-colored rocks, in which the fossils were found and for Rose Letwin, who sponsored the expeditions which recovered these fossils.
The designated holotype for the genus and type species, "Mapusaurus roseae", is an isolated right nasal (MCF-PVPH-108.1, Museo Carmen Funes, Paleontología de Vertebrados, Plaza Huincul, Neuquén). Twelve paratypes have been designated, based on additional isolated skeletal elements. Taken together, the many individual elements recovered from the "Mapusaurus" bone bed represent most of the skeleton.
Description.
"Mapusaurus" was a large theropod, and was roughly similar in size to its close relative "Giganotosaurus", with the largest known individuals estimated as about to in length or more and weighing about to . The longest individual for which Coria and Currie (2006) provided a concrete estimate in Table 1 (appendix lll) is the animal to which femur MCF-PVPH-208.203 belonged; this individual is estimated as long.
Coria and Currie note the presence of isolated bones from at least one longer individual, but do not provide a figure, instead finding the larger bones coherent with an individual of comparable size to "Giganotosaurus" holotype estimated at in length, although not with the same exact proportions, having taller and wider neural spines, a more elongate fibula ( compared to ) but more slender (81–89% the width as in "Giganotosaurus") as well as a wider pubic shaft in minimal dimensions (10% wider as indicated by a long fragment catalogued as MCF-PVPH-108.145), and with a differently proportioned skull, shorter in length than "Giganotosaurus" because the maxilla is not elongated (12 teeth compared to 14 in "Carcharodontosaurus"), but deeper in proportion due to this, as well as narrower (due to the narrow nasals). Considering this, a fragmentary maxilla is coherent with the size of the "Giganotosaurus"-sized individual (MCF-PVPH-108.169). A neural arch from an axis (MCF-PVPH-108.83) and a scapular blade fragment are also the same exact size as the same elements in "Giganotosaurus".
The weight estimate of is from a long femur with a circumference (MCF-PVPH-208.234).
Holtz estimated the maximum size of the animal at . This estimate has been cited in Drew Eddy and Julia Clarke (2011), and cited again in a phylogenetic table in a 2014 analysis by Canale "et al.". Gregory Paul gave a lower estimation of 11.5 meters (37.7 ft) and 5 metric tons (5.5 short tons).
It has been determined that "Mapusaurus" was diagnosed on autapomorphies, or unique traits, in regions of the skeleton that "Giganotosaurus" does not preserve. "Mapusaurus" only differs from "Giganotosaurus" in lacking a second opening on the middle quadrate, and in some details of the topology of the nasal rugosities.
Paleobiology.
The fossil remains of "Mapusaurus" were discovered in a bone bed containing at least seven individuals of various growth stages. Coria and Currie speculated that this may represent a long term, possibly coincidental accumulation of carcasses (some sort of predator trap) and may provide clues about "Mapusaurus" behavior. Other known theropod bone beds include the "Allosaurus"-dominated Cleveland-Lloyd Dinosaur Quarry of Utah, an "Albertosaurus" bone bed from Alberta and a "Daspletosaurus" bone bed from Montana.
Paleontologist Rodolfo Coria, of the Museo Carmen Funes, contrary to his published article, repeated in a press-conference earlier suggestions that this congregation of fossil bones may indicate that "Mapusaurus" hunted in groups and worked together to take down large prey, such as the immense sauropod "Argentinosaurus". If so, this would be the first substantive evidence of gregarious behavior by large theropods other than "Tyrannosaurus", although whether they might have hunted in organized packs (as wolves do) or simply attacked in a mob, is unknown. The authors interpreted the depositional environment of the Huincul Formation at the Cañadón del Gato locality as a freshwater paleochannel deposit, "laid down by an ephemeral or seasonal stream in a region with arid or semi-arid climate". This bone bed is especially interesting, in light of the overall scarcity of fossilized bone within the Huincul Formation. An ontogenetic study by Canale "et al." (2014) found that "Mapusaurus" displayed heterochrony, an evolutionary condition in which the animals may retain an ancestral characteristic during one stage of their life, but lose it as they develop. In "Mapusaurus", the maxillary fenestrae are present in younger individuals, but gradually disappear as they mature.
Classification.
Cladistic analysis carried out by Coria and Currie definitively showed that "Mapusaurus" is nested within the clade Carcharodontosauridae. The authors noted that the structure of the femur suggests a closer relationship with "Giganotosaurus" than either taxon shares with "Carcharodontosaurus". They created a new monophyletic taxon based on this relationship, the subfamily Giganotosaurinae, defined as all carcharodontosaurids closer to "Giganotosaurus" and "Mapusaurus" than to "Carcharodontosaurus". They tentatively included the genus "Tyrannotitan" in this new subfamily, pending publication of more detailed descriptions of the known specimens of that form.
The following cladogram after Novas "et al.", 2013, shows the placement of "Mapusaurus" within Carcharodontosauridae.
Paleoecology.
As previously mentioned, the Huincul Formation is thought to represent an arid environment with ephemeral or seasonal streams. The age of this formation is estimated at 97 to 93.5 Mya. The dinosaur record is considered sparse here. "Mapusaurus" shared its environment with the sauropods "Argentinosaurus" (one of the largest sauropods, if not the largest), "Choconsaurus", and "Cathartesaura". Abelisauroid theropods "Skorpiovenator" and "Ilokelesia" also lived in the region.
Fossilized pollen indicates a wide variety of plants was present in the Huincul Formation. A study of the El Zampal section of the formation found hornworts, liverworts, ferns, Selaginellales, possible Noeggerathiales, gymnosperms (including gnetophytes and conifers), and angiosperms (flowering plants), in addition to several pollen grains of unknown affinities. The Huincul Formation is among the richest Patagonian vertebrate associations, preserving fish including dipnoans and gar, chelid turtles, squamates, sphenodonts, neosuchian crocodilians, and a wide variety of dinosaurs. Vertebrates are most commonly found in the lower, and therefore older, part of the formation.


Zignoichthys

Zignoichthys oblongus is an extinct prehistoric relative of the pufferfish and porcupine fish that lived during the Lutetian epoch of the Eocene. "Z. oblongus"' fossils are found from the Monte Bolca lagerstätte of what is now Italy.
It lacked a pelvis, and probably could not inflate its body like its modern-day relatives. In life, it would have resembled a paunchy triggerfish or a pufferfish with an elongated, downturned face.


Geology of Mayotte

As part of the Comoro Islands chain in the Mozambique Channel, the geology of Mayotte is virtually the same as the geology of the Comoros, the rest of the island chain which is independent of France. The island resulted from the rifting of Madagascar away from Africa as well as "hotspot" mantle plume activity, and is also impacted by seismicity and deformation associated with the East African Rift. However, because Mayotte is a part of France its geology is significantly more researched than that of other islands in the chain.
Mayotte is a primarily volcanic island rising steeply from the bed of the ocean to a height of on Mont Bénara. Two volcanic centres are reported, a southern one (Pic Chongui, , with a breached crater to the NW, and a northern centre (Mont M'Tsapéré, ) with a breached crater to the south-east. Mont Bénara is between these two peaks, approximately at the contact point of the two structures. Volcanic activity started about 7.7 million years ago in the south, ceasing about 2.7 million years ago. In the north, activity started about 4.7 million years ago and lasted until about 1.4 million years ago. Both centres had several phases of activity. Ash bands found in the corals suggest some continuing minor activity. The most recent age reported for an ash band is 7000 year BP.
Stratigraphy & Tectonics.
As with other islands in the Comoros chain, Mayotte's location in the Mozambique Channel is tectonically complex, due to the displacement of the Malagasarian microcontinent from the margin of the supercontinent Gondwana.
Mesozoic.
From the Permian until the Early Jurassic, the Comoros region experienced Karoo rifting, on an northeast–southwest trend. During the Middle Jurassic and Early Cretaceous, an ocean basin, running north–south, formed along the Davie Ridge.
Cenozoic.
The volcanoes in the Comoros date to the recent past of the Pliocene, Pleistocene and Holocene period.
The oldest volcano on the chain is 7.7 million years old, on Mayotte. Volcanoes are older further east. Anjouan is 3.9 million years old and Moheli is five million years old. Grande Comore is the youngest at only 10,000 years old. Some geologists have proposed that the Comoros is an example of one of 11 primary mantle plumes worldwide.
The East African Rift System became active 22 to 25 million years ago in the Miocene and its offshore extent is the youngest. The rift system causes seismicity, extensional deformation and created the offshore Kerimbas Graben.
Natural hazards.
From 2002 to 2006, the French Geological Survey conducted an extensive natural hazards survey throughout the 17 districts of Mayotte and published a hazard zonation map. Some parts of the island face threats from storm surges and landslides and areas with weathered volcanic rock face heightened risk from seismic activity.
Hydrogeology.
Groundwater on Mayotte is sourced from several aquifers in the fractured basalt. The island's aquifer is one of the best studied basalt aquifers other than Hawaii and the Canary Islands. The perched aquifers are separated by units of rock that act as aquitards and aquicludes, slowing or nearly stopping the flow of water.
Natural resources.
There is very little mining in Mayotte, aside from the production of building material. In some cases, coral is mined to produce lime for concrete.
Earthquake Swarm.
Starting in May 2018 there have been many minor earthquakes under the eastern flank of the volcano constituting what is generally referred to as a "swarm". The exact nature of the forces behind this swarm remain unclear as of March 2019. The French government geological agency, the BRGM are maintaining a website on the events at this link. The (current, 2019) leading theory is about a combination of magma emplacement into the seabed over an extended period and a partial collapse of the magma chamber's roof, but that is still under debate. A set of seabed seismic recorders was put into the ocean in February 2019, for retrieval in about September of that year, which should give better locations and directional "solutions" for future events.
In November 2018 a very peculiar seismological signal was produced as part of this swarm. The November 11 2018 seismic event occurred about east of the coast of Mayotte. It was recorded by seismograms in many place including Kenya, Chile, New Zealand, Canada, and Hawaii located almost away. The seismic waves lasted for over 20 minutes but despite this, no one felt it.
The peculiar thing about this event is that instead of the normal range of frequencies of noise being detected, only a very narrow range was detected - the event is sometimes described by seismologists as "monochrome". In a discussion captured on Twitter, ideas were batted around about a partial collapse of a magma chamber roof, but at this time (2019-03) work continues to understand the event. Estimated depths of to are compatible with a magma chamber within the volcano substructure, but other solutions for the depth of the source structure have been proposed.


Overoraptor

Overoraptor (meaning "piebald thief") is a genus of paravian theropod dinosaurs, which was closely related to "Rahonavis", from the Late Cretaceous (Cenomanian) Huincul Formation of Gondwana, present-day Argentina. It includes one species, Overoraptor chimentoi.
Etymology.
The generic name "Overoraptor" is derived from the Spanish "overo", meaning piebald, in reference to the color of the fossil bones. The specific name, "O. chimentoi", refers to Roberto Nicolás Chimento, who discovered the remains.
Description and classification.
Although the holotype is very fragmentary, it exhibits an unusual combination of features that reveal a novel phylogenetic position. The forelimb exhibits a bird-like morphology that includes, among other things, a robust ulna, while the hindlimb appears to have been adapted for a cursorial lifestyle. A "sickle-claw" similar to that of dromaeosaurs is also present. Both a flight-adapted forelimb and a cursorial hindlimb are present in "Rahonavis", also from Gondwana, and the describers suggest the two are closely related taxa.
The describers ran a phylogenetic analysis and recovered a novel position for "Overoraptor" and "Rahonavis", being outside of Unenlagiidae and Avialae, to which the latter has sometimes been assigned to. Their cladogram is shown below, based on a previous study by Agnolin & Novas (2013):
Paleoenvironment.
"Overoraptor" was found in the Huincul Formation, a geological unit that has been extensively studied in recent years. "Overoraptor" lived alongside theropods such as the noasaurid "Huinculsaurus", abelisaurids like "Skorpiovenator", "Ilokelesia" and "Tralkasaurus", carcharodontosaurids like "Mapusaurus" and indeterminate theropods like "Gualicho" and "Aoniraptor". Sauropods were represented by the rebbachisaurids "Cathartesaura" and "Limaysaurus", the titanosaurs "Argentinosaurus" and "Choconsaurus", and some unnamed species. Ornithischians were represented by unnamed iguanodonts.


Caspana

Caspana is a Chilean village located 85 km northeast of the city of Calama, in the gorge carved by the river that shared its name and that is a tributary of the Salado River. Agricultural terraces form part of the landscape of the area. Its church dates from the 17th century.


Kerkis

Kerkis or Kerketeus (Greek, Modern: Κέρκης, "Kérkis"; Ancient: Κερκετεύς, "Kerketeús") is a mountain, forming the bulk of the western part of the Greek island of Samos. Its highest peak, named "Vigla" (Βίγλα), is at 1,434 m (4,701 ft), making it the second-highest peak in the East Aegean (after Fengari on Samothrace). The mountain's name, in both ancient and modern forms, means roughly, "belonging to Circe".
The mountain has a whitish color due to being composed of marble, especially visible on several exposed cliffs. It is considered a sanctuary for numerous plants and animals, some of them endangered, and so is part of the European Union's Natura 2000 network of protected sites. There are also several small monasteries on its slopes, as well as a number of caves. Of these, the most notable is the Cave of Pythagoras on the eastern slope, in which Pythagoras is reputed to have hidden from the tyrant Polycrates prior to going into exile in Italy.


Drosophila statzi

Drosophila statzi is an extinct species of flies, belonging to the family Drosophilidae. It is from the Upper Oligocene of the Rott Formation in Germany.
The name "Drosophila elegans" Bock and Wheeler, 1972, though a junior synonym, is used for an extant species found in Taiwan and the Philippines but the International Commission on Zoological Nomenclature ruled for the name to be conserved for the extant species of fruit fly by suppression of its unused senior homonym (replaced by †"Drosophila statzi" (Statz, 1940) Ashburner and Bachli, 2004).


Geology of Newfoundland and Labrador

The geology of Newfoundland and Labrador includes basement rocks formed as part of the Grenville Province in the west and Labrador and the Avalonian microcontinent in the east. Extensive tectonic changes, metamorphism and volcanic activity have formed the region throughout Earth history.
Newfoundland.
In contrast to neighboring Labrador, the island of Newfoundland is largely underlain by younger rocks. The Churchill, Nain, Superior and Grenville Province present in Labrador were all small continents or pieces of continental lithosphere that joined to form sections of the proto-North American continent Laurentia and the broad stable region known as the Canadian Shield. By the end of the Precambrian in the Neoproterozoic, continental crust which had come into existence in the Archean nearly 2.5 billion years had already experienced up to eight supercontinent cycles.
In the late Precambrian and Paleozoic, Avalonia (named after the Avalon Peninsula in Newfoundland) formed as a volcanic island arc off the coast of the supercontinents Pannotia which lost land through rifting and became Gondwana. This volcanic island arc was later split into different areas, but currently underlies southern New England, Maine, Nova Scotia, Prince Edward Island, southern New Brunswick, southern Ireland, England, Wales, Belgium, the Netherlands and much of north Germany. Northwest Newfoundland includes older rocks affected by the Grenville orogeny in the late Proterozoic during the collision of continents to form the previous supercontinent Rodinia.
Examples of ancient rocks from this period include the late Precambrian Harbour Main Group ignimbrite and ash flow tuff with obsidian and augite in the center of the Avalon Peninsula. Rocks of similar age were forming on Grenville Province basement rock in what would become western Newfoundland, such as the Round Pond granite formed 602 million years ago. Sedimentary and volcanic rocks 15 kilometers thick are exposed in the Avalon Peninsula, deposited in rift basins as flysch and molasse with volcaniclastic rocks in submarine fans. The Gaskiers Formation holds diamictite that may have formed during the Snowball Earth glaciations and Ediacaran fossils and microfossils have been found in some rocks. Northern Newfoundland at the edge of the Laurentian continent witnessed columnar flood basalts in the Cloud Hills area into the Cambrian.
The Avalon Zone is an area of 550 million year old sedimentary and volcanic rocks exposed only in the east that preserves the original geology of the microcontinent and extends 600 kilometers out to sea forming the below water Flemish Cap.
By the early Devonian, the Avalonia microcontinent and the Bronson Hill island arc, collided with Laurentia to form the mid-sized continent Euramerica, causing the Taconic orogeny. The collision closed the Iapetus Ocean and obducted the Laurentian continental margin under the two island arcs. The process produced a strange bulged up area of mantle material to the surface as peridotite in Gros Morne National Park, essentially the only area on the Earth's surface where mantle material is present as cool, crystallized rock. It also created an ophiolite zone where oceanic crust was preserved on land.
Geologists group the rocks in this area into the Humber Zone and the Dunnage Zone, with the Dunnage Zone's southern edge defined by the Gander River Ultrabasic Belt. The neighboring Gander Zone has siltstone, shale and quartz sandstone as well as deformed rocks and granite. The sediments were deposited on the continental margin during the closure of the Iapetus Ocean.
By 356 million years ago, Gondwana collided with Euramerica, closing the Rheic Ocean and creating the supercontinent Pangea, which left Newfoundland and the Avalonian microcontinent (also known as terrane) far inland and brought widespread interior desert conditions around the world. Newfoundland was re-exposed to the ocean in the Triassic when rifting began to form new oceanic crust and opened the Atlantic Ocean.
Labrador.
Labrador is part of the eastern Canadian Shield and intrusive igneous or metamorphic rocks are the most common, with sedimentary rocks in some areas. Four of the seven Canadian Shield provinces make up Labrador. Archean age rocks and east-west structural trends mark the Superior Province (a small area in the west near Quebec) which encompasses the Ashuanipi Complex granulite and granodiorite intruded by pyroxene-rich felsic plutons. The Nain Province runs along the northeast coast and also has Archean-age rocks, although a greater northward trend. The only exception is gneiss overlain by metasedimentary and metavolcanic rocks in the southeast, which were recrystallized and metamorphosed during 1.42 billion year old orogeny. A major anorthosite-adamellite pluton intrudes the province. South of the Davis Inlet, the Hopedale Gneiss is the defining rock unit.
Nain Archean gneiss is overlain to the north of the community of Nain, Newfoundland and Labrador by the undeformed Ramah Group shale, sandstone and quartzite from the Aphebian. The Mugford Group tholeiite basalts and pyroclastic flows overlie similar sedimentary rocks. The volcanic rocks are between 1.49 and 2.3 billion years old. The Nain Province is subdivided into the Makkovik-subprovince, which is mainly made up of the 25,000 foot thick Aillik Group quartzofeldspathic, argillite, limestone, conglomerate, paragneiss and iron formations.
The Churchill Province is situated inland in north-central Labrador and was deformed during the Hudsonian orogeny. Anorthosite intrusions partly obscure it in places, but a mylonite zone marks it northern boundary. Structural geologists divide it into the undeformed sedimentary and volcanic rocks Kaniapiskau Supergroup in the Labrador Trough (including gabbro sills and plutons) in the west and high-grade anorthosite and gneiss in the east.
Virtually all of southern Labrador belongs to the major Grenville Province, which underlies much of eastern Canada and the northern US. Extensive faulting and mylonite marks its northern boundary with the other structural provinces. Archean gneisses were metamorphosed again during the Grenville orogeny and intruded by anorthosite-adamellite plutons. The Kaniapiskau Supergroup extends into the Grenville Province, marked by marble and quartzite.
During the Paleozoic around 334 million years ago, flood basalts emplaced in northern Newfoundland and southern Labrador.
Through the Mesozoic and into the Cenozoic, the landscape eroded, shedding sand into the Labrador Shelf, mainly from older metasediments and metavolcanic rocks that reached amphibolite grade on the sequence of metamorphic facies. Close to Makkovik, breccia from the Mesozoic, cut by lamprophyre-carbonatite dikes marks the opening of the Labrador Sea.
The region experienced repeat glaciations during the Pleistocene. Glaciomarine silts and mud records the melting of the glaciers on the Labrador Shelf, with significant deposition around 20,000 years ago. Analysis suggests most of these sediments originated on land in Labrador, although large amounts of limestone (which is completely absent in the Labrador) indicate a second source to the north, likely Paleozoic limestone on the Hudson Strait and Ungava Bay.
Natural resource geology of Labrador.
Massive iron deposits are found in the Labrador Trough along with copper, uranium and molybdenum. Iron forms in chert from the Ungava Bay to the Grenville Front, over a span of 700 miles, while copper and nickel minerals such as pyrite, pyrrhotite, sphalerite and galena form dispersed deposits or massive bodies in Kaniapiskau Supergroup rocks. The Aillik Group hosts uranium as uraninite and pitchblende dispersed in veins in pegmatite, argillite, granulite and quartzite.


Isalo II

Isalo II, also known as the Makay Formation, is an informal Triassic geological unit in Madagascar.


Rhacheosaurus

Rhacheosaurus is an extinct genus of marine crocodyliform belonging to the family Metriorhynchidae. The genus was established by Christian von Meyer in 1831 for skeletal remains from the Tithonian (Late Jurassic) of Germany.
History and classification.
A phylogenetic analysis in 2009 showed that several long-snouted species formerly classified in the related genera "Geosaurus", "Enaliosuchus", and "Metriorhynchus" were in fact more closely related to the original specimens of "Cricosaurus", and thus were re-classified into this genus. This analysis also resurrected the generic name "Rhacheosaurus".
Niche partitioning.
Several species of metriorhynchids are known from the Mörnsheim Formation (Solnhofen limestone, early Tithonian) of Bavaria, Germany: "Rhacheosaurus gracilis", "Dakosaurus maximus", "Geosaurus giganteus" and "Cricosaurus suevicus". It has been hypothesised that niche partitioning enabled several species of crocodyliforms to co-exist. The top predators of this Formation appear to be "D. maximus" and "G. giganteus", which were large, short-snouted species with serrated teeth. The long-snouted "C. suevicus" and "R. gracilis" would have fed mostly on fish, although the more lightly built "Rhacheosaurus" may have specialised towards feeding on small prey. In addition to these four species of metriorhynchids, a moderate-sized species of "Steneosaurus" was also contemporaneous.


Cuyosuchus

Cuyosuchus is an extinct genus of archosauriform reptile. Its fossils have been found in Late Triassic-aged rocks of the Cacheuta Formation, Cuyo Basin, Mendoza, Argentina. "Cuyosuchus" is based on MCNAM 2669, a partial postcranial skeleton including 26 vertebrae from all parts of the spinal column, ribs, partial pectoral girdles, part of the pelvis, upper arms and part of the lower arms, the left thigh bone and shin, pitted armor scutes, and fragments. It was described in 1961 by Osvaldo Reig and named after the Cuyo Basin; the type species is "C. huenei", referring to German paleontologist Friedrich von Huene. Although originally described as a proterosuchid, restudy by Julia Desojo and colleagues in 2003 found that it could not be assigned to any family.


Liwia

Liwia is a genus of nektaspid, a soft-bodied stem-group chelicerate. It includes the following species, both are known from borehole samples several kilometers in depth from the Zawiszyn Formation in Poland, which has also yielded "Peytoia infercambriensis."


Hellissandur

Hellissandur () is a village and part of the Snæfellsbær municipality at the northwestern tip of Snæfellsnes peninsula in western Iceland.
Once an important fishing post, the village has recently experienced growth in tourism. The maritime museum has examples of the turf roof houses once common across Iceland, as well as marine engines and Iceland's oldest rowing boat (1826). According to the 2011 census, Hellissandur and nearby Rif have 544 inhabitants. Hellissandur is one of the first and oldest fishing villages in Iceland and is traced back to the 16th century.
One of the points of interest near Hellissandur is the Snæfellsjökull glacier, made famous by Jules Verne in his "Journey to the Center of the Earth". Just outside the village, there is the northern entrance to the Snæfellsjökull National Park, which surrounds the western and southern sides of the glacier. Nearby is the 412 metre tall Gufuskálar radio mast, the tallest structure in Western Europe, located 2 kilometres westward.


Save the Oak Ridges Moraine

Save the Oak Ridges Moraine ("STORM") is a coalition of 25 citizen's groups and individuals dedicated to preserving the ecologically sensitive Oak Ridges Moraine in Ontario, Canada. Formed in 1989, its primary goal has been to lobby the Government of Ontario to create legislation to protect the moraine.
The coalition was founded when two groups (one from Peterborough that was supporting a group in Durham Region, and one in King Township) discovered that they had the same name (STORM), and networked with other local groups to organize a first coalition meeting. The brief that the Peterborough group prepared had a significant impact on the Environmental Assessment Advisory Committee who held a hearing to hear perspectives on the disputed land use proposal near Kendall in Durham.
STORM has played an important role in triggering political action to preserve the Oak Ridges Moraine. Soon after its formation, it raised the profile of the Moraine at both the local and provincial levels, causing the provincial government to declare an "expression of provincial interest" in the Moraine in 1990.
STORM was appointed as a member of the government-sponsored "Oak Ridges Moraine Technical Working Committee." In addition to STORM, membership on the committee included: Regional Municipalities of Durham, Peel and York, MNR, MMAH, MOE, Toronto and Region Conservation Authority (TRCA), Ganaraska Region Conservation Authority (GRCA), Conservation Council of Ontario (CCO), Urban Development Institute (UDI), Aggregate Producers Association of Ontario (APAO), and Federation of Ontario Naturalists (FON). The committee operated from 19911994. Its task was to develop a long-term preservation strategy for the moraine. The committee's final report, submitted to the province in 1994, was never implemented. Instead, the province expanded the powers of the municipalities in administration of the lands that were the subject of the committee's report.


Bow Lake (Alberta)

Bow Lake is a small lake in western Alberta, Canada. It is located on the Bow River, in the Canadian Rockies, at an altitude of 1920 m.
The lake lies south of the Bow Summit, east of the Waputik Range (views including Wapta Icefield, Bow Glacier, Bow Peak, Mount Thompson, Crowfoot Glacier and Crowfoot Mountain) and west of the Dolomite Pass, Dolomite Peak and Cirque Peak.
Bow Lake is one of the lakes that line the Icefields Parkway in Banff National Park and Jasper National Park, other such lakes being Hector Lake, Lake Louise, Peyto Lake, "Mistaya Lake", "Waterfowl Lakes", "Chephren Lake" and "Sunwapta Lake".
Historical Simpson's Num-Ti-Jah Lodge is located on the shores of Bow Lake at the foot of Mount Jimmy Simpson.
Bow Lake is the closest lake to the headwaters of Bow River, and has a total area of 3.21 km2. Water in the lake is meltwater of the Bow Glacier and its turquoise colouring is due to glacial till.


Volcanic Eifel

The Volcanic Eifel or Vulkan Eifel () is a region in the Eifel Mountains in Germany that is defined to a large extent by its volcanic geological history. Characteristic of this volcanic field are its typical explosion crater lakes or maars, and numerous other signs of volcanic activity such as volcanic tuffs, lava streams and volcanic craters like the Laacher See. The Volcanic Eifel is still volcanically active today. One sign of this activity is the escaping gases in the Laacher See.
Geographical location.
The Volcanic Eifel stretches from the Rhine to the Wittlich Depression. It is bordered in the south and southwest by the South Eifel, in the west by Luxembourg and Belgian Ardennes and in the north by the North Eifel including the Hohes Venn. To the east the Rhine forms its geographical boundary, with no volcanicity immediately beyond it.
The Volcanic Eifel is divided into three natural regions:
The centre of the Volcanic Eifel is the region around Daun and Manderscheid and the areas within the Mayen-Koblenz district.
The landscape of the Volcanic Eifel is dominated by recent volcanism. Volcanic craters, thick pumice and basalt layers and maars create a diverse landscape that clearly witnesses to very recent events in geological terms.
The entire Volcanic Eifel covers an area of about and has a population of about 200,000.
Volcanoes.
The following volcanoes belong to the Eifel, sorted by height in metres (m) above sea level (Normalhöhennull, NHN):
Laacher See.
Of particular note is the volcanic caldera known as Laacher See, the site of an eruption around 12,900 years ago that had an estimated VEI of 6.
Future activity.
There is thought that future eruptions may occur in the Eifel, as:
In 2020, Professor Kreemer noted that Eifel was the only region within an area of Europe studied where ground motion happened at significantly higher levels than expected. It is possible that such movements originate from a rising magma plume. This activity does not imply an immediate eruptive danger, but might suggest an increase in volcanic and seismic activity in the region.


Microsuchus

Microsuchus is an extinct genus of mesoeucrocodylians, belonging to Notosuchia. Fossils have been found in the Bajo de la Carpa Formation, dating to the Santonian stage of the Late Cretaceous.
Classification.
Originally classified as a goniopholidid on the basis of the platycoelus vertebral centra, "Microsuchus" was recently redescribed and recovered as either a neosuchian or notosuchian. Diagnostic features include the presence of a bulge lateral to the prezygapophyses of the second sacral vertebra, elongated posterior zeugopodia, and proximal caudal centra with a triangular cross section. A 2017 cladistic analysis of "Razanandrongobe" further clarified the phylogenetic position of "Microsuchus" by recovering it as a primitive notosuchian.


Adwa (volcano)

Adwa (also known as Caaduba, Amoissa, or Dabita) (1733 m/5686 ft.) is a stratovolcano in Ethiopia, located in the western Somali Region region and has a 4 by 5 km caldera. Due to the location of the volcano near the boundary between Afar and Issa tribes, little is known about the past and present behavior of the volcano. However, an earthquake and InSAR study conducted by Derek Keir and colleagues shows that a magma intrusion around 5 km deep and 8 km long emanated away from the eastern side of the volcano in May 2000.


Kangnasaurus

Kangnasaurus (meaning "Farm Kangnas lizard") is a genus of iguanodontian ornithopod dinosaur found in supposedly Early Cretaceous rocks of South Africa. It is known from a tooth and possibly some postcranial remains found in the early-Aptian Kalahari Deposits Formation. It was probably similar to "Dryosaurus".
Description and history.
"Kangnasaurus" was named in 1915 by Sidney H. Haughton. The type species is "Kangnasaurus coetzeei". The generic name refers to the Kangnas farm; the specific name to the farmer, Coetzee. "Kangnasaurus" is based on holotype SAM 2732, a tooth found at a depth of 34 metres in a well at Farm Kangnas, in the Orange River valley of northern Cape Province, South Africa. The age of these rocks, conglomerates in an ancient crater lake, is unclear; they are thought to be from the Early Cretaceous (probably ealy-Aptian). Haughton thought SAM 2732 was a tooth from the upper jaw, but Michael Cooper reidentified it as a lower jaw tooth in 1985. This had implications for its classification: Haughton thought the tooth was that of an iguanodontid, while Cooper identified it as from an animal more like "Dryosaurus", a more basal ornithopod.
Haughton described several other fossils as possibly belonging to "Kangnasaurus". These include five partial thigh bones, a partial thigh bone and shin bone, a partial metatarsal, a partial shin and foot, vertebrae, and unidentified bones. Some of the bones apparently came from other deposits, and Haughton was not certain that they all belonged to his new genus. Cooper was also not certain, but described the other specimens as if they did belong to "Kangnasaurus".
"Kangnasaurus" is usually regarded as dubious, although a 2007 review of dryosaurids by Ruiz-Omeñaca and colleagues retained it as potentially valid, differing from other dryosaurids by details of the thigh bone. Like other basal iguanodontians, it would have been a bipedal herbivore.


Sierra Baguales

Sierra Baguales or Sierra de los Baguales is a mountain range in the southernmost Andes. Sierra Baguales is a long east-west chain, secondary to the main chain of the Andes that lie further west. It lies along the border between Chile and Argentina near the localities of Puerto Natales and Río Turbio.
Geology.
The mountain range contains a series of cirques formed by glaciers. Many cirques developed in the Pleistocene Epoch from isolated glaciers that existed separedly from ice sheets further west. The rocks of Sierra Baguales belong to various formations of Magallanes Basin. These rocks contain fossils of plants, mammals and marine invertebrates.
Stratigraphy.
From top to bottom the following formations make up Sierra Baguales:
On the eastern slopes of Sierra Baguales various lithic artifacts have been found. Human occupation of eastern foothills begun no later than 4,500 years before present.


Bushveld Sandstone

The Bushveld Sandstone is a geological formation dating to roughly between 201 and 189 million years ago and covering the Carnian to Norian stages. The Bushveld Sandstone is found in Transvaal, South Africa and is a member of the Stormberg Group. As its name suggests, it consists mainly of sandstone. Fossils of the prosauropod dinosaur "Massospondylus" have been recovered from the Bushveld Sandstone.
The Bushveld Sandstone was thought to be Late Triassic age, but was considered to be temporally correlative to the Clarens Formation by Smith et al. (1993).
Vertebrate fauna.
Dinosaur tracks located in Transvaal.


Dysalotosaurus

Dysalotosaurus ("uncatchable lizard") is a genus of herbivorous iguanodontian dinosaur. It was a dryosaurid iguanodontian, and its fossils have been found in late Kimmeridgian-age rocks (Late Jurassic) of the Tendaguru Formation, Tanzania. The type and only species of the genus is D. lettowvorbecki. This species was named by Josef Felix Pompeckj in 1920 in honor of the Imperial German Army Officer, Paul von Lettow-Vorbeck. For much of the 20th century the species was referred to the related and approximately contemporary genus "Dryosaurus", but newer studies reject this synonymy.
Discovery.
Thousands of "Dysalotosaurus" bones and bone fragments have been recovered from the Tendaguru Formation in Tanzania, Africa. It has been suggested that all of these specimens were part of a herd that was killed in a mass death event.
Description.
"Dysalotosaurus" was a small, relatively basal iguanodontian ornithopod. It lacked the large thumb spikes found in later iguanodontians, and was more adapted for bipedalism than its larger relatives with its short front limbs and long, counter-balancing tail. "Dysalotosaurus" had powerful and long hind limbs, suggesting it was relatively cursorial compared to "Iguanodon" and other members of the clade.
Based on CT scans of the braincase, it is believed that "Dysalotosaurus" held its head dorsally (pointing straight forward) when not feeding. The same study also suggested, based on the morphology of the inner ear, that "Dysalotosaurus" was not able to discern between high- and low-frequency sounds (like most herbivorous dinosaurs). However, it also had other adaptations that are commonly associated with derived hearing abilities, rendering its sensory capabilities unclear.
In 2016, Gregory S. Paul estimated "Dysalotosaurus"' length at , and its weight at .
Ontogeny.
Various specimens of "Dysalotosaurus" are known, all representing animals that were not yet sexually mature at the time of their deaths. Ontogenetic studies demonstrate typical aging trends, such as a lengthening of the snout and relative shrinking of the orbit. Differences in dentition as the animals aged also suggest a change from an omnivorous diet early in life to fully herbivorous feeding habits as an adult. This switch reflects the general evolutionary trend towards obligate herbivory among iguanodontians and other ornithopods.
Palaeobiology.
"Dysalotosaurus" was a precocial dinosaur, which experienced sexual maturity at ten years, had an indeterminate growth pattern, and maximum growth rates comparable to a large kangaroo.
Palaeopathology.
In 2011 paleontologists Florian Witzmann and Oliver Hampe from the Museum für Naturkunde and colleagues discovered that deformations of some "Dysalotosaurus" bones were likely caused by a viral infection similar to Paget's disease of bone. This is the oldest evidence of viral infection known to science.
The discovery of a hemivertebra (spinal malformation) in another specimen likely caused scoliosis and other pathologic effects on the animal during its life. This malformation occurs in almost every vertebrate clade, though this is the first known evidence of the condition in dinosaurs.
Palaeoecology.
Contemporary dinosaurs were "Kentrosaurus", various sauropods including "Giraffatitan" and "Dicraeosaurus", and large theropods including "Megalosaurus" and "Ceratosaurus". Pterosaurs are also common in the Tendaguru Formation, as well as mammaliaformes (ancestral to mammals).
During the Jurassic, Tendaguru was part of the semi-arid coastline of Gondwana. "Dysalotosaurus" fossils were discovered in strata that were deposited in structures characteristic of tidal flats and lagoons.


Eriocranites

Eriocranites is an extinct genus of moth in the family Elachistidae. It contains only one species, Eriocranites hercynicus, which was described from Willershausen in Germany. It is dated to the Pliocene.


Oenonella

Oenonella is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the later part of the Arenig stage of the Ordovician Period, approximately 478 to 471 million years ago.


Malarguesaurus

Malarguesaurus (meaning "Malargue lizard" after the Malargüe Department of Mendonza Province) is a genus of titanosauriform sauropod dinosaur from the Late Cretaceous of Mendoza Province, Argentina. Its fossils, consisting of tail vertebrae, chevrons, ribs, and limb bones, were found in the early to middle Coniacian-aged (~89 million years old) Los Bastos Formation of the Neuquén Group. The type species, described by González Riga "et al." in 2008, is "M. florenciae".
Description.
Described as a robust sauropod, it was initially described as being closely related to "Ligabuesaurus" and "Phuwiangosaurus", and Mannion et al. (2013) more precisely recovered it as a member of Somphospondyli. The cladistic analysis of "Patagotitan" recovered "Malarguesaurus" as a close relative of the Asian "Ruyangosaurus".
Like other sauropods, "Malarguesaurus" would have been a large quadrupedal herbivore. "Malarguesaurus" is the second sauropod dinosaur discovered in Mendoza Province; the first is "Mendozasaurus neguyelap".


Cristiano Dal Sasso

Cristiano Dal Sasso (born 12 September 1965) is an Italian paleontologist.
Biography.
He was born in Monza, Italy and has been working since 1991 for the Milan Natural History Museum where he is the curator of fossil reptiles and birds. He was the technical coordinator of the excavations of Besano, which brought to light the complete skeleton of a Middle Triassic marine reptile of the order of Ichthyosaurs, the "Besanosaurus" with embryos in the belly, published in 1996 along with Giovanni Pinna.
He studied "Scipionyx", the first dinosaur found in Italy at Pietraroja, whose description appeared in Nature in 1998. This small theropod dinosaur, nicknamed "Ciro", generated much publicity because of the unique preservation of large areas of petrified soft tissue and internal organs such as muscles and intestines. The fossil shows many details of these, even the internal structure of some muscle and bone cells.
Cristiano Dal Sasso also described "Saltriovenator", considered as the earliest known Ceratosauria and largest Early Jurassic theropod, discovered in 1996 in a quarry in Saltrio, in northern Italy.


Edith Kristan-Tollmann

Edith Kristan-Tollmann nee Edith Kristan (born 14 April 1934 in Vienna; died 25 August 1995) was an Austrian geologist and paleontologist. A prolific scientist with an interest in micropalaeontology and especially the foraminifera of the Triassic (in the then Tethys Ocean) and the Jurassic eras, Kristan-Tollmann published widely in her field. She is also known for originating with her husband Alexander Tollmann a thoroughly documented theory of the evolution of human legend and social structures as a result of a massive impact event which struck multiple points on earth. The latter has become known as Tollmann's hypothetical bolide.
Life.
The daughter of an elementary school director, Kristan-Tollmann initially wanted to become a teacher herself. She received her secondary school diploma from a teacher-training school. However, she shifted her focus to study geology, paleontology and petrography in Vienna under the tutelage of Othmar Kühn, Felix Machachki, Hans Wieseneder and Leopold Kober. She received her doctorate in geology and paleontology in 1959 in the region of Hohe Wand. In the same year she completed her education, she married her classmate Alexander Tollmann, with whom she had a son Raoul in 1967. During her studies she also worked as a religion teacher in Vienna.
Kristan-Tollmann specialized in micropalaeontology and especially the foraminifera of the Triassic (in the then Tethys Ocean) and the Jurassic periods. She described numerous new taxa. In addition to foraminifera, she later treated ostracods and other microfossils and invertebrate macro-fossils such as crinoids (which were a particular favorite of hers), corals, mollusks, brachiopods, and sea cucumbers. After initially working as a freelancer for the Geological Survey of Austria, from 1961 to 1968 she was a micropaleontologist adviser to the OMV. She was a visiting scholar at the Swedish Geological State Institute in Stockholm in 1966 and a Humboldt Fellow at the Naturmuseum Senckenberg and the University of Frankfurt in 1971/72, and then at the University of Tübingen in 1972/73. From 1976 to 1978 she conducted research at the Natural History Museum Vienna.
In 1982 she received a post-doctoral degree in micropaleontology in Vienna and gave courses at the universities in Graz and Innsbruck.
She died in 1995 of cancer.
Career.
Kristan-Tollmann collected samples almost all over the Alps and expanded her sampling in the 1970s worldwide (Turkey, Iran, China, Timor, New Guinea, Australia, Japan, Central and North America as the Sonoran Desert in Mexico), on some quite dangerous trips to remote areas. For example, in 1975 she narrowly escaped the East Timor genocide. She often traveled alone, but prepared for her trips quite thoroughly. A major focus of her worldwide work was the global remote correlation of paleontological data in the Triassic Tethys and early Jurassic, the Black Jurassic. She discovered a surprising similarity in the fauna and the sequences, which also led to revisions of descriptions of taxa. Through her work, many of the early macro-fossils from this period which were first described in Austria in the classical period of paleontology and had been described differently in other parts of the world were reassigned. It also led to revisions in the theory of ocean currents in the Tethys Ocean, as larvae were posited to have traveled great distances as part of plankton in that body of water. For one example, she explained the correspondence of observably similar rock bodies in Alpine regions and Chine in the Triassic period as a function of global fluctuations in sea level. She explored the division between the Tethys Ocean and Panthalassa in New Caldonia.
Kristan-Tollmann was a founding member of the Shallow Tethys and was involved in the organization of their meetings, for example, at the 4th Congress in 1994 at the Castle Albrechtsberg the Tollmanns. In 1991 she also organized the 3rd meeting of German-speaking ostracod researchers in Albrechtsberg.
She authored around 120 scientific publications and was the first to describe around 500 new taxa. Her publication areas included foraminifera, ostracods, echinoderms, and calcareous nannofossils.
The collection primarily reflects Edith Kristan-Tollmann's work on Foraminifera from the Triassic and Lower Jurassic and also contains a small amount of material published by her husband Alexander on the Neogene of Austria (full publication list for AT in Lein, 2007). Edith Kristan-Tollmann published extensively not only on Foraminifera but also on ostracods, echinoderms (holothurians, micro-crinoids) and calcareous nannofossils (full publication list in Lobitzer, 1996). Published foraminifera include the genera Variostoma, Diplotremina, Plagiostomella, Duostomina, Asymmetrina from the Triassic (1960) and Scyphodon, Callonina and Nephrosphaera from the Silurian of Austria (1971) and numerous new species. Although early work focused on the Alps and Austria, later published material embraced the Triassic of Iran, India, China, Japan, Indonesia, Papua-New Guinea, Australia and New Zealand, with discussions of taxonomy and distribution patterns throughout Tethys. A number of publications cite material as deposited in 'Sammlung Kristan-Tollmann, Geologisches Institut der Universität Wien' but this is not correct and the specimens were, in fact, retained as a private collection. The Kristan-Tollmann Collection is currently being accessed into the Senckenberg Foraminifera Collections.
From 1978 to 1992, she published along with her husband, Tollmann, the communications of the Austrian Geological Society. From 1975 to 1977 and again from 1990 to 1992, she was on the Advisory Board of the Paleontological Society.
Catastrophic theories.
Kristan-Tollmann had been interested in the history of the priesthood and in theology and archaeology since her youth. In 1992, she co-published with her husband Alexander Tollmann an article that posited that around 7,500 BCE a Mesolithic disaster occurred when a comet struck the earth. According to the couple, the comet divided into seven fragments that struck the earth in seven places, documented in the myths and religious tracts of multiple cultures. The pair followed up this publication with a book on the same subject in 1993, "Und die Sintflut gab es doch: vom Mythos zur historischen Wahrheit" ("And The Flood Did Exist: From the Myth to the Historical Truth"), which became a bestseller in Austria and Germany. The book attributes to this disaster, with has become known as Tollmann's hypothetical bolide, the origin of priesthood (as a person who facilitates sacrifices to the gods), world religions, the Christian Genesis flood narrative, the myth of Atlantis and many other things. The authors credited the meteorite impact theory of Luis Walter Alvarez as influencing their own theories of a geological catastrophe that so influenced human history. They also postulated that such impact events were recurrent on about a 10,000 year cycle, citing dust bands in the Antarctic ice core around 17,000 to 18,000 years old as an indication that a previous impact had contributed to warming at the end of the last ice age. The theories reported in both the article and the book were the subject of fierce criticism. Other scientists tended to the theory that the Tollmanns had pushed their interpretation of the data too far, although the evidence of a comet impact at the time they posit has not been thoroughly discredited.
Kristan-Tollmann also contributed to a follow-up book with Alexander Tollmann which was not published until after her death, "Das Weltenjahr geht zu Ende", in which they predicted that, based on the prophecies of Nostradamus, the world would end at the turn of the millennium.
Political activism.
Kristan-Tollmann was active in the anti-nuclear movement and on behalf of environmental protection. Her husband played a significant role in Green politics in Austria. In "Und die Sintflut gab es doch", they also warn against exposure to the numerous nuclear power plants around the world, especially with regard to geological (earthquake) and impact risks.


Carandaisuchus