EXTINCTION vs RELATED IMPACT CRATER

EXTINCTION vs RELATED IMPACT CRATER

by: Charles O’Dale

In my articles I use the term crater to define a circular impact depression and the term structure to define an impact crater that is severely altered by erosion.

These five mass extinctions have happened on average every 100 million years or so since the Cambrian, although there is no detectable pattern in their particular timing. Each event itself lasted between 50 thousand and 2.76 million years (The Conversation – COSMOS).


Although the exact ratios of the different atmospheric components of Earth throughout its entire history are unknown, there were large amounts of methane present in the atmosphere prior to 2.5 billion years ago and virtually no oxygen. With the arrival of oxygen, the methane was destroyed, and the planet’s greatest ice age began. The evolution of the atmosphere is one of the strong indirect pieces of evidence we have for Earth having an active biological history going back all the way to immediately after its formation. VICTOR PONCE / SAN DIEGO STATE UNIVERSITY

Haden Era