Crews constructing the SFPUC’s new Calaveras Dam in the East
Bay uncovered a geologic layer that happened to contain thousands of fossils. Through
a cooperative agreement with the University of California Museum of
Paleontology (UCMP; Berkeley, CA), those fossils are now being cleaned,
analyzed, and catalogued.
“We transferred all of the fossil specimens to UCMP this
year,” said JT Mates-Muchin, the SFPUC’s Environmental Compliance Manager who
helped broker the agreement. “Fossils are a non-renewable resource. It is
important that they are carefully catalogued and preserved for scientific
research.”
A Megalodon Shark Tooth Being Scanned in the Lab.
The lead researcher and lab manager at UCMP, Cristina
Robins, and her team are beginning to tease information out of the fossils. Fifteen million years ago, the site of
Calaveras Reservoir was located at the mouth of a vast inland sea that
stretched into the Central Valley. Just
like in the seas of today, there was a lot of plant and animal life throughout.
When they died, they left a fossil record.
This included sharks, lots of sharks. More than 2,000 shark
teeth have been found from 35 species. These include many from requiem and mako
sharks. Some teeth from the 35-foot megalodon shark have turned up as well.
What do these shark teeth tell us?
- The area around Calaveras Dam was once completely submerged by water.
- The depth of the ocean could have been as deep as 700 to 1,000 meters.
- The distribution of species is similar to fossil locations as far as way at Gatun, Panama.
- Calaveras has a higher diversity of sharks than other sites.
At this point the paleontologists have only begun to scratch
the surface of the Calaveras fossils, no pun intended.
The teeth from 35 different species of shark have been found at the Calaveras Dam Replacement Project.
We look forward to learning more secrets about the Bay
Area’s past through these amazing fossils.
Keep up to date on the Calaveras fossils through the UCMPFacebook Page.
