Permian Permian The Permian is a geologic period and system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic period 251.902 Mya. It is the last period of the Paleozoic era; the following Triassic period belongs to the Mesozoic era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the city of Perm. The Permian witnessed the diversification of the early amniotes into the ancestral groups of the mammals, turtles, lepidosaurs, and archosaurs. The world at the time was
Robert Frost Trail (Massachusetts) Hadley, South Hadley, Amherst, Granby, Belchertown, Pelham, Shutesbury, Leverett, Sunderland, Wendell and Montague. The Robert Frost Trail might be divided into three general geo-ecological landscapes. Both the Holyoke Range and Mount Toby were formed 200 million years ago between the end of the Triassic period and the beginning of the Jurassic. The Holyoke Range, part of the Metacomet Ridge that extends south to Long Island Sound, are composed of basalt, an extrusive volcanic rock. This basalt ridge is the product of several massive lava flows hundreds of feet deep that welled up in faults created by the rifting apart of