(Polished) Geological
Time: Late Paleocene
Size (25.4
mm = 1 inch): Stromatolites are 150 mm by 75 mm by 15 mm (maximum)
Fossil Site:
Flagstaff Formation, Cove River Member, Central Utah, USA
Fossil:
ST101
Price: Sold
Description:
This is a stromatolite as found in its natural un-cut form with
the exception of one side that has been cut and polished to show
the distinctive stromatolitic structure. A most unique feature
is that this example is inordinately young for stromatolites.
This one comes from the Late Paleocene of Utah from what was
known as Lake Flagstaff. At its maximum extent Lake Flagstaff
extended from the Uintah Mountains to the North to today’s
Bryce Canyon in the South. The rocks of this formation document
a time in Earth’s history of a growing greenhouse effect.
Globally the temperatures rose by some 5 degrees Centigrade from
about 58.5 million years ago to about 52.5 million years ago,
with a concomitant decrease in rainfall. Locally the temperature
rise is thought to have been some twice the global value. The
lake transitioned from freshwater to saline during that time,
then reverted to fresh some time in the Eocene.
The
stromatolites were deposited during the saline period.
Stromatolites have persisted to the modern day in such places
as Shark Bay, Australia where they continue their billions
of years old lifestyle. While this piece would make a fine
present
for any natural history buff, anyone who appreciates art would
also be glad to get thus wonderful specimen as a gift. |
|