Deccan Traps
Channel: 宇宙のすべての知識 プリンシピア
Date: 2019-02-02

Deccan Traps, by Wikipedia https://en.wikipedia.org/wiki?curid=8688 / CC BY SA 3.0

#Volcanism_of_India
#Plate_tectonics
#Large_igneous_provinces
#Cretaceous_paleontological_sites_of_Asia
#Cretaceous_volcanism
#Paleocene_volcanism
#Geology_of_India
#Geology_of_Maharashtra
#Former_climate_forcing_agents
Deccan Traps

Deccan Traps are a large igneous province located on the Deccan Plateau of west-central India (17°–24°N, 73°–74°E) and are one of the largest volcanic features on Earth. They consist of multiple layers of solidified flood basalt that together are more than thick, cover an area of , and have a volume of . Originally, the Deccan Traps may have covered , with a correspondingly larger original volume.

The term "trap" has been used in geology since 1785–1795 for such rock formations. It is derived from the Swedish word for stairs ("trappa") and refers to the step-like hills forming the landscape of the region.

The Deccan Traps began forming 66.25 million years ago, at the end of the Cretaceous period. The bulk of the volcanic eruption occurred at the Western Ghats some 66 million years ago. This series of eruptions may have lasted less than 30,000 years in total.

The original area covered by the lava flows is estimated to have been as large as , approximately half the size of modern India. The Deccan Traps region was reduced to its current size by erosion and plate tectonics; the present area of directly observable lava flows is around .

The release of volcanic gases, particularly sulfur dioxide, during the formation of the traps contributed to climate change. Data point to an average drop in temperature of 20 °C (36 °F) in this period.

Because of its magnitude, scientists have speculated that the gases released during the formation of the Deccan Traps played a role in the Cretaceous–Paleogene (K–Pg) extinction event (also known as the Cretaceous–Tertiary extinction). It has been theorized that sudden cooling due to sulfurous volcanic gases released by t...