What is the Eocene and when did it end?
Q: What is the Eocene and when did it end?
A: The Eocene was a geologic epoch in Earth's history, and it ended 33.9 million years ago.
Q: What marked the beginning of the Oligocene?
A: The end of the Eocene marked the beginning of the Oligocene.
Q: What happened during the transition from the Eocene to the Oligocene?
A: There was a large-scale floral and faunal turnover, with many marine and aquatic organisms going extinct, including the last of the ancient cetaceans.
Q: Was there any major impact or volcanic event that caused the climatic changes at the beginning of the Oligocene?
A: At first, climatic change was not linked with any single major impact or catastrophic volcanic event, but volcanic activity may have played a role.
Q: Were there any meteorite impacts around the time of the transition from the Eocene to the Oligocene that may have played a role in the extinction event?
A: Yes, there were several large meteorite impacts, including one that created the Chesapeake Bay impact crater 40km in diameter and another at the Popigai crater 100km in central Siberia.
Q: What is the leading scientific theory on climate cooling during this time period?
A: The leading scientific theory is that there was a decrease in atmospheric carbon dioxide, which slowly declined in the mid to late Eocene and possibly reached some threshold about 34 million years ago.
Q: What event marks the beginning of ice sheet coverage on Antarctica, and how is it linked to the transition from the Eocene to the Oligocene?
A: The Oligocene Oi-1 event, an oxygen isotope change, marks the beginning of ice sheet coverage on Antarctica, and it is closely linked to the transition from the Eocene to the Oligocene.
