Are flood basalts responsible for mass extinctions?
Are flood basalts responsible for mass extinctions?
Flood basalts were Earth’s largest volcanic episodes that, along with related intrusions, were often emplaced rapidly and coincided with environmental disruption: oceanic anoxic events, hyperthermals, and mass extinction events.
What is the flood basalt eruption?
Flood Basalts are high volume eruptions that flood vast areas of the Earth, covering broad regions with flat lying lava surfaces. They are said to be the result of mantle convection through hot spots, which occur sporadically in time and place.
What are the 4 main causes of mass extinctions?
Past mass extinctions were caused by extreme temperature changes, rising or falling sea levels and catastrophic, one-off events like a huge volcano erupting or an asteroid hitting Earth. We know about them because we can see how life has changed in the fossil record.
Which flood basalts led to Permian extinction?
Two other major mass extinctions have been correlated with flood basalt episodes: the end-Cretaceous event (65 Mya) with the Deccan basalts of India and the end-Permian event (251 Mya) with the Siberian basalts.
How flood basalts are formed?
Flood basalt is formed by an eruption or series of eruptions of large volcanic episodes that cover vast stretches of land or ocean floor with flows of mafic igneous rocks (basalt lava flows). A flood-basalt province is popularly known as Trap (Deccan Traps in India).
How do continental rift eruptions form flood basalts?
How do continental-rift eruptions form flood basalts? A mantle plume rises beneath a region undergoing rifting. As the plume reaches the base of the lithosphere, it has a bulbous head containing a lot of partially molten rock.
What extinction events are associated with flood basalts such as the Deccan Traps?
Three of the largest mass extinctions, the Permo-triassic, Triassic-Jurassic and the Cretaceous-Tertiary, correspond with the eruptions of the Siberian Traps, the Central Atlantic Magmatic Province, and the Deccan Traps, respectively.
Where and why do flood basalts form?
What is a continental flood basalt province?
Abstract. Large areas of the continents appear to have been covered by vast thicknesses of laterally extensive basaltic lava flows at various stages during the past 1000 Ma, apparently fed from fissures rather than central vent volcanoes. These are referred to as continental flood basalt provinces or CFBs.
