**2. What are Anorthosites?**

Anorthosites are a fascinating type of igneous rocks which are composed predominantly of calcium-rich plagioclase feldspar and mostly formed during Precambrian times. It has to be reminded that all found anorthosites on Earth are contained coarse crystals (See **Figures 1** and **2**) but moon anorthosite samples are finely crystalline which were collected from The Moon highlands (See **Figures 3**–**5**).

Lunar anorthosites within the light-colored areas of the Moon's surface are subject of investigations to understand the history of moon evolution. It seems the light coloured lunar highland crust was formed by the crystallization and floatation of plagioclase from a global magma ocean, although the actual generation mechanisms are still debated [5].

Additionally, Lunar anorthosites are known for displaying a limited range of plagioclase (∼94 to 98) and basis nearly recent studies at 2019 [6, 7], the plagioclase trace-element variations from Apollo ferroan anorthosites (FAN) samples (collected by the Apollo 15 and 16 missions) display more significant chemical heterogeneity and it can give us a better illustration about the timing and formation mechanisms of the Moon's crust. This study clarified a chemical heterogeneity within the LMO1 as a global moon feature in the crustal formation. It seems that maybe during mantle overturn, the act of exhuming deep maficrich cumulates to the base of the lunar crust would have triggered decompression

1 The lunar magma ocean (LMO).

**Figure 1.** *Large outcrop of anorthosite in the Helleren massif, Jibbeheia, Rogaland-Norway [1].*

#### **Figure 2.**

*Anorthosite from the Pare Mountains with mafic lense and Grt (spell out) corona [2].*

melting. These are likely to be small degree (<10%) partial melts2 , which are typically enriched in incompatible elements3 . It is not contradict with the idea of

2 Partial melting is the transformation of some mass solid rock fraction into a liquid as a result of heat input, decompression or flux addition. This resulting liquid is nominated either magma or lava as if eruption from a volcano.

3 Incompatible elements own difficulty in entering cation sites of the minerals, so they get concentrated in the melt phase of magma.

**Figure 3.** *Black and White Photograph of Apollo 15 Sample (s) 15415-Nasa - Lunar Samples [3].*

#### **Figure 4.**

*Ferroan Anorthosite (1836 grams)- 60025. NASA #S72–41586. Cube and scale are 1 cm. Note the thick black glass coating and numerous micrometeorite pits [4].*

#### **Figure 5.**

*Plane-polarized and cross-polarized photos of thin Section 60025,21. Field of view is 2.5 mm. S79–27300 and 301 [4].*

local LMO magmas infiltration4 by more evolved liquids through metasomatism5 process, too.

The terrestrail anorthosites can be divided into five types: Archean-age anorthosites, Mid-ocean ridge and transform fault anorthosites, Anorthosite xenoliths in other rocks, Layers within Layered Intrusions and Proterozoic anorthosite as the most abundant anorthosite kind. Lunar geological studies also clarified that the light areas of the moon also consist of very old anorthosite. The dark areas of the moon, many of which are circular, consist of the black volcanic rock basalt. In fact, the primary pre-Nectarian lunar highlands are contained light-grey anorthosites which are caused at the early moon crust formation.

## **3. Anorthosites- geologic timescale**

The geological history of Moon is categorized into six major epochs which is called the lunar geologic timescale. The boundaries of this time scale are subject to

4 Infiltration is defined as the flow of liquid such as water from aboveground into the subsurface.

5 Metasomatism is replacing one mineral with another that mineral dissolution and minerals deposition are occurred at the same time.

large impact events which affected the lunar surface through time as crater formation and their absolute ages got determined by radiometric dating of obtained lunar samples. The lunar surface is generally modified by impact cratering and volcanism, so, it is possible to define the lunar geological events in time basis on stratigraphic principles [8–10].

In the moon history, the Nectaris Basin and other major moon basins were formed by large impact events at the Nectarian Period (from 3920 million years ago to 3850 million years ago). Also, the pre-Nectarian period of the lunar geologic timescale is between 4.53 billion years ago to 3.92 billion years ago. It is extended between the initial Moon formation time to Nectaris Basin by a large impact. During this time, these light anorthosites came from the cooling of the surface lunar magma ocean (LMO). The impact event is subject the collision of astronomical objects like asteroids, comets or meteoroids on the surface of planets and moons, and they have a significant role in the evolution of the Solar System like the Earth and the Moon. For instance, approximately 4.5 billion years ago the Moon created from the ejecta of a collision between the proto-Earth and a Mars-sized planetesimal and it seems a giant hit causing from this hit at both parent bodies (I, e the earth and moon) [11].

The pre-Nectarian system was characterized by the formation of an anorthositic crust and its subsequent brecciation by large basin- forming impact events [12]. In fact, it contains the minerals that were emplaced at the lunar surface over the period extending from the moon formation to the excavation of the Nectaris impact- basin. According to studies, the lunar highlands being compose of anorthositic gabbros and gabbroic anorthosites, but the pre-Nectarian terrain are now probably breccias (rather than pristine igneous rocks) produced during the excavation of the basin cavities.

During the Nectarian Period (*from 3920 million to 3850 million years ago*), the Nectaris Basin and other major lunar mare or sea basins (Volcanic-basaltic lava as the dark spots of moon) were formed by large impact events that Ejecta from Nectaris forms the upper part of the densely cratered terrain found in lunar highlands. In the following of Nectarian Period, along with the Late Heavy Bombardment of the Inner Solar System, the huge Mare Imbrium basin was formed at 3850 to 3800 million years ago (The Early Imbrian epoch), then, this basin and other formed basins get filled with basalt mostly during the subsequent Late Imbrian epoch (3800 to about 3200 million years ago) (See **Figure 6**).

The lunar geological timescale went away on with *Eratosthenian* (from 3,200 million to 1,100 million years ago) and the massive basaltic volcanism of the Imbrian period tapered off and ceased during this long span of lunar time. In the following, impact craters lost their bright ray systems (thrown out radial streaks of fine ejecta at the formation of impact crater) due to space weathering processes6 and It ends up to *The Copernican period* (From 1.1 billion years ago to the present day) in which light freshly excavated lunar surface has been growing to become darker over time due to space weathering processes.

This lunar geologic time scale is based on the recognition of few geomorphological markers, but it is practical to correlate the geological events at the solar system, in specific too much far distant early Earth time. The Hadean eon of Earth between 4.6 to 4 billion years ago which it begun with the Earth formation and ended up before the earliest-known rocks on Earth. According to the Lunar geologic timescale, this eon can be subdivided to *Pre-Nectarian* (the formation of the Moon's crust, 4533 to 3920 million years ago) and Nectarian (the Late Heavy Bombardment, from 3920 to 3850 million years ago). Some Hadean rocks as the oldest Earthen rocks

6 Including, bombardment surface planetary bodies like the Moon or the Mercury by different sizes of meteorites, coalition of solar cosmic rays, solar wind and galactic cosmic rays.

**Figure 6.** *The location of lunar Mare Imbrium [13].*

were found out at western Greenland, northwestern Canada, and Western Australia with the oldest dated zircon crystals in a metamorphosed sandstone conglomerate in the Jack Hills of Western Australia which these xenocryst zircons formed after 200 million years after Earth formation.

The Earth history can be subdivided to few Eons which are the Hadean, the Archean, the Proterozoic and the Phanerozoic (See **Figure 7**). Each eon can be divided into eras, which are in turn divided into periods, epochs and ages. The Phanerozoic (541 million years ago to the present) is the current geologic eon with abundant animal and plant life and it begun at the Cambrian Period when the first hard shells of animals developed and have been preserved as fossil record. The time before the Phanerozoic Eon which is the Hadean, Archaean and Proterozoic eons are called the Precambrian, too.

During the Archean eon (between 4,000 to 2,500 million years ago), the Earth's crust had cooled enough in forming continents and also the emergence of life. At the early Archean, the Earth's heat flow was nearly three times as high as it is today and also it was still twice the current level at the transition from the Archean to the Proterozoic (2.5 billion years ago) due to the heat remnant of planetary formation and the decay of radioactive elements.

Therefore, it can be assumed that these volcanic activities at the Precambrian had great role in The Cambrian explosion at 541 million years ago to rapid emergence life diversification at a short period time between 13 to 25 million years and this trend has being continued. It owns to say the life was mostly simple unicell organisms at the Precambrian, but it got suddenly was turned into colonies as multi-cellular life after the snow earth period.

There is a lot of exposed rocks relevant to this eon which can be observed around the globe such as Greenland, Siberia, the Canadian Shield, the Baltic Shield, India,

**Figure 7.** *Earth geologic time scale- Scale: millions of years [14].*

#### *A View to Anorthosites DOI: http://dx.doi.org/10.5772/intechopen.97787*

Brazil, western Australia, and southern Africa. For example, granitic rocks have been significantly observed from the crystalline remnants of Archean crust, and also other rocks like monzonites (An igneous intrusive rock with equal amount of plagioclase and alkali feldspar and less than 5% quartz) anorthosites (*mostly plagioclase feldspar (90–100%*)) and, too.


*<IP_ADDRESS> Appraisal of team members*

Feedback to individuals and the team reinforces positive behaviours and allows for continual development of the team. It also provides an opportunity for deficits to be identified and remediated. A 360-evaluation process may be utilised whereby many colleagues, regardless of discipline or seniority, will provide evaluation for a team member [7]. Interpersonal skills and professionalism are the core emphasis of this approach.

## *<IP_ADDRESS> Research*

ICU team members must keep up to date with the latest emerging evidence in their respective fields. Critical care medicine is a technology-dependent speciality which is rapidly evolving. Specific assessment of new techniques, medications and equipment should be incorporated into a local coordinated research agenda. This is necessary to achieve continuously improving, team-based healthcare. Team members must be provided with sufficient time and resources to engage in relevant research, and feedback their results into clinical practice.

## *<IP_ADDRESS> The patient and family as team members*

Vital to a high-performing ICU team is the inclusion of the patient and their family as integral members of the team. This concept of shared decision-making is gradually replacing a more paternalistic style of directing care [8]. It is important to involve the family in clinical decision making and to allocate sufficient time to meet with them. The patient's needs and expectations are the driving force for the team's

efforts, and some neonatal and paediatric intensive care units now facilitate unrestricted family visiting and limited participation in medical rounds.

## *3.1.2 Barriers to high-performance teamwork in the intensive care unit*

## *<IP_ADDRESS> The changing team*

As staff change from day to night shift and junior doctors rotate through training posts, the multidisciplinary ICU team is continually changing. Although some team members will be a constant presence, the changing nature of the team can threaten its performance [9]. It may be difficult for new team members to join a well-established and experienced team and it takes time and effort for team members to build a trusting relationship with each other. The rotation of care providers may also influence the continuity of care delivered to the patient. This highlights the importance of having established written goals for patient care.

## *<IP_ADDRESS> Interpersonal relationships*

With the amalgamation of many personalities and healthcare specialities, it is inevitable that conflict may occur within the ICU team. Tension may arise due to the existence of differing priorities or perspectives of team members [10]. Occasionally, the priorities of the team may not align with those of the patient or family. The relationship between team members and the patient and family is important in the overall delivery of care, job satisfaction and incidence of compassion fatigue. Tensions can be exacerbated by inefficient or infrequent communication between team members this contributes to disharmony in the patient's bedspace, especially if conflicting pieces of information and opinions are being passed onto the patient and their family. Although reaching an agreement between all team members is challenging, it can be facilitated with early and open communication. Senior team members must oversee conflict resolution with maturity and compassion [11, 12].

## *<IP_ADDRESS> Psychological stress*

The ICU can be a demanding work environment which poses several challenges to team members. Caring for a critically unwell child and their family can be distressing. Team members are often faced with stressful resuscitations, emergencies, and death. Ethical dilemmas are often encountered and can have a psychological impact on the staff involved. A supportive environment is essential to allow staff members to manage these stressors and continue to function as a high-performing team. Debriefing should be used after critical incidents and staff should have access to a counselling service.

## *<IP_ADDRESS> Resource limitations*

Whilst dependent largely upon the collaborative efforts of individual team members, a high-performance healthcare team does require organisational support to function maximally. Adequate resources must be in place to support the work of the team. Health informatics and technological resources should facilitate seamless communication between team members. Financial support should be in place to allow for education and research. Appropriate facilities should be provided for team meetings,

education sessions and simulation. Medical equipment should meet minimum standards to deliver care. Team members should be provided with adequate time for completion of clinical duties, continual professional development, and rest.

## **3.2 Regulatory aspects of medical care in the intensive care unit**

Regulation of medical practice in any speciality should focus on 'right touch'. This is a balance between onerous rules which may lead to defensive practice and light-touch regulation which may not be sufficient to guide good practice. Moving the emphasis of regulation upstream, to the issues which can positively impact a physician's professionalism will potentially reduce the number and significance of breaches of conduct and competence. Many regulatory bodies around the world now use this 'right touch' approach to medical regulation. There has been a move away from self-regulation in many jurisdictions, with the establishment of statutory bodies with a non-medical majority. This is a deliberate action to give reassurance to patients that public protection is the key remit of regulation.

In consultation with the public and the profession, high standards of education and practice are developed. These high standards of medical undergraduate and postgraduate education, postgraduate and speciality training, medical ethics and communication are then applied to educational institutions and individual doctors. Following assessment, recommendations for domains of improvement are made by the regulatory authority and followed up in a cycle of appropriate, targeted regulation. Tailored guides to specific areas of medical practice may be produced by a medical regulator to inform doctors and the public of the standards expected e.g., Telemedicine. A regulator will usually maintain a register of doctors who are qualified in that profession. That register is open to the public for inspection and assurance.

The Intensive Care Unit is a key part of a hospital environment. Intensive or critical care medicine has expanded over the last 2 decades to include premature neonates (Neonatology), infants and children (Paediatric Intensive Care) and adults (Adult ICU). Most ICUs will provide education and training to medical practitioners as part of structured training programs. The curriculum and formal assessment of the training program are decided by the certifying professional body e.g., European Society of Intensive Care Medicine (ESICM). A hospital and its medical staff will have a relationship with a medical regulatory body to ensure that there is protection of the public interest in its interactions with doctors employed within the hospital. All doctors must demonstrate their licence or registration with their regulatory body as part of their terms of employment. This provides the public with confidence that their doctor has the necessary medical qualifications to provide medical services.

## *3.2.1 Education and training*

Regulation extends into education and training with the setting of standards and the periodic evaluation of these standards by the regulatory body. In the ICU, all doctors are expected to meet a basic standard of medical practice and conduct, in addition to demonstrating ongoing learning. There may be overlap with individual training programs and a sharing of compliance data. Accreditation of training bodies by the regulator may be a feature of some healthcare systems, but the principles are the same. A doctor may be asked to demonstrate fitness to practice through a process of investigation if there is a significant complaint made against the doctor. Management of a complaint against a professional is outlined below in Section 2.7.

## *3.2.2 Continued professional development*

Each doctor working in the critical care environment has a professional and ethical obligation to keep up to date with clinical developments. Each year specific training courses may be mandated e.g., resuscitation procedures and algorithms. Professional competencies in communication are important in the ICU where giving patients and families bad news is a vital part of the senior medical role. Miscommunication is a common area of complaint where families have a grievance around how important information was imparted by a doctor. There are simulation modules and training drills in communication skills available.

## *3.2.3 Supervision and revalidation*

All doctors in training programs must be supervised by a doctor senior in experience. Supervision is a skilled intervention, providing oversight of clinical activity, guidance and the capacity for feedback and debriefing. Doctors of all training levels and ability should have access to a supervisor. As critical care medicine is an acute speciality where patients' clinical status can deteriorate rapidly, supervision should be accessible 24/7. Doctors returning to clinical practice in the ICU following a significant period of absence should be asked to work within a structured program of revalidation to ensure that the doctor is ready to return to full practice and deliver safe patient care. This revalidation program may be sourced from within larger intensive care units, or from the doctor's professional body.