The Great Dying's Engine
Around 252 million years ago, the Earth's crust split open across what is now Siberia, initiating the largest known volcanic event in the last 500 million years. This was not a typical mountain volcano; it was a large igneous province known as the Siberian Traps. For roughly two million years, fissures in the ground poured out immense volumes of basaltic lava, covering an area of about 7 million square kilometers. The total volume of erupted material is estimated at around 4 million cubic kilometers, enough to cover the entire United States in magma a kilometer deep.
The eruptions occurred across the Permian-Triassic boundary and are considered the primary cause of the most severe extinction event in Earth's history. Today, this region, particularly the Putorana Plateau, displays the geological aftermath. The landscape is characterized by step-like hills formed by layers of solidified flood basalt, which is where the name "traps" originates—from the Swedish word "trappa" for stairs. The lava flows are thousands of meters thick in some places, a record of a planetary catastrophe.