Trias refers to the Triassic Period, which is a geological time period that occurred approximately 252 to 201 million years ago, and is the first period of the Mesozoic Era. The term "Trias" is derived from the Latin word "triad," which signifies the three distinct rock layers that were identified during this period.
During the Triassic Period, the Earth experienced significant changes. It marked the aftermath of the Permian-Triassic extinction event, which wiped out approximately 96% of marine species and around 70% of terrestrial species. The Trias witnessed the emergence and diversification of new life forms, including the evolution of early dinosaurs, mammals, and flowering plants.
Geologically, the Triassic Period is defined by the occurrence of sedimentary rocks, such as sandstones, shales, and limestone, which were predominantly deposited in shallow marine environments, as well as on land. Fossil evidence from this period reveals the existence of various marine reptiles, such as ichthyosaurs and plesiosaurs, as well as the ancestors of modern crocodiles.
Additionally, the Triassic Period is characterized by the breakup of the supercontinent Pangea, as landmasses began to drift apart, forming the precursor continents of today. This division of landmasses contributed to the formation of new ocean basins and the subsequent evolution of diverse terrestrial ecosystems.
In summary, Trias or the Triassic Period, represents a significant geological time period in Earth's history when new life forms started to emerge and diversify following the mass extinction event that occurred at the end of the Permian Period.
