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Deccan
traps:
Other scientists think the extensive volcanic
activity in India known as the Deccan Traps may
have been responsible for, or contributed to,
the extinction. However, paleontologists remained
skeptical, as their reading of the fossil record
suggested that the mass extinctions did not take
place over a period as short as a few years, but
instead occurred gradually over about ten million
years, a time frame more consistent with massive
volcanism. There was also a certain general distrust
of a group of physicists intruding into their
domain of expertise.

A very large impact crater has been recently reported
in the sea floor off the west coast of India.The
researchers suggest that the impact may have been
the triggering event for the Deccan Traps. However,
this feature has not yet been accepted by the
geologic community as an impact crater.
* Extreme volcanic
activity and the additional acid rain may perhaps
have altered the Earth's climate sufficient to
generate mass extinction. The delayed Cretaceous
was a time of high tectonic action and additional
volcanic action. The super continent Pangaea was
splitting up and the continents were taking on
their modern-day forms. Extreme volcanic activity
would discharge dust and acidic chemicals (like
sulphuric acid) into the atmosphere, which causes
global cooling, and possibly, mass extinctions.
* Changes in the
Earth's orbit that might have caused climactic
cooling might have caused the extinction. In this
circumstance, the dinosaurs couldn't acclimatize
to the cold, but the hairy mammals could. This
is steady with the type of weather in the late
Cretaceous; toward the ending of the Cretaceous,
there was a drop in sea level, causing land exposure
on all continents, more seasonality, and greater
extremes between equatorial and polar temperatures.
*Mammals eating dinosaurs'
eggs have been suggested as a cause of the K-T
extinction. This doesn't explain why so many other
species went extinct, or why there are chemical
anomalies in the K-T layer.
* Large amounts of
methane changing the Earth's atmosphere (causing
a greenhouse effect). The methane source would
be from deep-sea algae deposits and/or from plant-eating
dinosaur’s digestion by-products.
*The herbivorous
dinosaurs' over-foraging and the carnivorous dinosaurs
over-culling of the herbivorous dinosaurs could
have triggered mass starvation.
* A nearby supernova
(an exploding star) could have bathed the Earth
in deadly radiation.
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