The Siberian Traps (Russian: Сибирские траппы, Sibirskiye trappy) form a large region of volcanic rock, known as a large igneous province, in Siberia, Russia. The massive eruptive event which formed the traps, one of the largest known volcanic events of the last 500 million years of Earth's geological history, continued for a million years and spanned the Permian–Triassic boundary, about 251 to 250 million years ago.
The term "traps" is derived from the Swedish word for stairs (trappa, or sometimes trapp), referring to the step-like hills forming the landscape of the region, which is typical of flood basalts
Source : Wikipedia
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