Tungus Syneclise, a large sedimentary basin containing thick sequences of Early-Mid Paleozoic aged carbonate and evaporite deposits, as well as Carboniferous-Permian aged coal bearing clastic rocks. When heated, such as by igneous intrusions, these rocks are capable of emitting large amounts of toxic and greenhouse gases. Effects on prehistoric life One of the major questions is whether the Siberian Traps were directly responsible for the Permian–Triassic mass extinction event that occurred 250 million years ago, or if they were themselves caused by some other, larger event, such as an asteroid impact. A recent hypothesis put forward is that the volcanism triggered the growth of Methanosarcina, a microbe that then emitted large amounts of methane into Earth's atmosphere, ultimately altering the Earth's carbon cycle based on observations such as a significant increase of inorganic carbon reservoirs in marine environments. This extinction event, also colloquially called the Great Dying, affected all life on Earth, and is estimated to have led to the extinction of about 81% of all marine species and 70% of terrestrial vertebrate species living at the time. Some of the disastrous events that affected the Earth continued to repeat themselves five to six million years after the initial extinction occurred. Over time a small portion of the life that survived the extinction was able to repopulate and expand starting with low trophic levels (local communities) until the higher trophic levels (large habitats) were able to be re-established. Calculations of sea water temperature from δ18O measurements indicate that at the peak of the extinction, the Earth underwent lethally hot global warming, in which equatorial ocean temperatures exceeded . It took roughly eight to nine million years for any diverse ecosystem to be re-established; however, new classes of animals were established after the extinction that did not exist beforehand. Palaeontological evidence further indicates that the global distribution of tetrapods vanished, with very rare exceptions in the region of Pangaea that is today Utah, between latitudes bounded by approximately 40°S to 30°N. The tetrapod gap of equatorial Pangaea coincides with an end-Permian to Middle Triassic global "coal gap" that indicates the loss of peat swamps. Peat formation, a product of high plant productivity, was reestablished only in the Anisian stage of the Triassic, and even then only in high southern latitudes, although gymnosperm forests appeared earlier (in the Early Spathian), but again only in northern and southern higher latitudes. In equatorial Pangaea,