Wednesday, March 25, 2009

Spring Break, Part 1

This spring break I went on a road trip with two of my fellow students - Lee Hall and Ash Poust. Lee needed to visit UCMP (the UC Museum of Paleontology at UC Berkeley) to meet with a coauthor and look at dinosaur teeth, and Ash just wanted to actually see the sun, and happily agreed to join us on our quest (for sun, data, and fossils).

Our trip began at 3:00am friday the 13th, and we drove in a single day from Bozeman all the way to the coast of Oregon, to check out an early Pleistocene marine unit which has in the past yielded some of the North Pacific's oldest true sea lion fossils.

Here's a view of the locality, with L. Hall prospecting in the foreground.

Here are some shell beds of the same formation.

A. Poust can be seen scrambling up a 'frozen' debris flow in order to scrutinize some exposures. On this same day, he found a very well preserved lower jaw of a sea lion as float on the beach - arguably the best fossil of the entire trip, one which can easily be the focus of a scientific paper all on its own.

Here's a photo of myself, standing on a small pinnacle of the 'rock' unit.

Our travels also took us to a Middle Pleistocene marine formation in Northern California, where fossils of birds, sea otters, and pinnipeds have been collected historically. Additionally, a mammoth scaphoid (wrist bone) and a claw core of a giant ground sloth (Megalonyx sp.) are also known from here. Along the same vein of terrestrial mammals, I found a small artiodactyl astragalus here. A. Poust found a proximal humerus of a 'medium' sized bird.

A. Poust (left) and L. Hall (right) can be seen prospecting the site here.

Here is a view up the exposure, showing the incredible volume of shelly material in this deposit. Shell beds this rich in invertebrates are sometimes referred to as coquinas.

A. Poust staring at the exposure.

Here's another photo from the Oregon locality, showing raised levees formed from debris flows traveling down the gully here.

Again, the Oregon locality. A. Poust (left) and L. Hall (right) looking for fossil vertebrates.

Several more posts are required to adequately document the rest of the spring break 'expedition'. Expect some posts about fieldwork in the Purisima Formation and the Santa Margarita Sandstone, coming soon.


ReBecca Foster said...

Don't let Ash fool you. He lived in Rock Island for too long, and of no sun in the winter! ;)
Send my hellos and have a great spring break!

Boesse said...

Hi Rebecca! I know he spent many years in the midwest, a darker, danker (and daresay flatter) place than Bozeman. Unfortunately, it took several days for the torrential downpour in Oregon and California to finally subside. We did, however, see some sunshine when we finally got to Santa Cruz (its always sunny in Santa Cruz...).

ReBecca Foster said...

Cool! John and I will be in Santa Cruz next week! :)

Boesse said...

Santa Cruz is my field area - my next post will be on some localities we visited there last week. Enjoy the surf and sun!

ReBecca Foster said...

Cool. I do not know as much about the Geology as John does (he is always pointing out the faults to me!). I look forward to your next post then. Maybe I can see it when we are down that way :)