Saturday, July 18, 2009

New skull!

Hey everyone,

Here is probably what will constitute the find of the summer. This is a partial skull. But, I'm not going to say what it is. A couple of you might have an idea, but I want real ID's based on cranial anatomy.

Good luck!

Saturday, June 27, 2009

Santa Cruz whale excavation

Well, a lot has certainly happened since I've been at field camp. A couple of big papers have come out, a seawall is being put up, and a whale skeleton in my field area was excavated.

Here is some footage of the excavation: http://www.ktvu.com/news/19696823/detail.html

Unfortunately, KTVU.com won't let me embed the video here, so just go to the above link.

What is pretty funny is that the guy who found it (Karl Heiman) says that he did so five months (I apologize, this used to say 'years' - typo) ago. This is OK, as a lot of people know about this thing, and have known so for a while. But *just* for the record, here's a photo I took of it in July 2005:
And, if that isn't enough, here's a photo of me beside the damn thing that my girlfriend took in March, 2006:
I'm just happy that this fossil is out of the ground. After watching the video I posted above over the weekend, I talked to my coauthor/colleague Frank Perry (Santa Cruz Museum of Natural History) and he gave me the contact info of David Haasl, who is in charge of the paleontological resources firm attached to the seawall construction project. Haasl has worked with Nick Pyenson on the whale fall assemblage from Ano Nuevo Island, further up the coast (in fact, I should make a post on that sometime in the future). Haasl was pretty happy to find out that the material collected from this project could be incorporated almost immediately (it has to be prepared first, after all) into my Master's Thesis; apparently, many fossils collected by CRM firms and the like often sit around unnoticed for a while. Additionally, I informed him of another whale skeleton, also articulated, that is now covered up with rip-rap; when I actually get to California I'll head down there next weekend and show them where it is (in fact, I have already posted a photo of this other articulated skeleton elsewhere on this blog: http://coastalpaleo.blogspot.com/2009/02/winter-break-field-photos-plus-another.html)

While it is unfortunate that this locality will be covered up indefinitely, I am delighted at the material being salvaged.

Friday, June 26, 2009

Field Camp, Part 4: Rattlesnakes!

Why's it always have to be snakes? Here are some photos compiled through the trip of some serious snakes. These are all western rattlesnakes (Crotalis viridis), the only species of rattlesnake in Montana.

I guess I was a little too close for this guy's comfort. The feeling was definitely mutual (but look how awesome this photo is!).

This photo definitely looks like it was staged. I promise it wasn't. There's a huge snake these guys are looking at.

Here's the huge rattler.
And again, all coiled up...
Students getting a look at another snake...
My friend startled a snake right as it struck a Richardson's Ground Squirrel (Spermophilus richardsonii). Here's the poor little bugger after it died. I stuck around to watch the snake eat it.

The head is down...
Now for the arms...
And the arms look like they're in. This is 20 minutes later.

Thursday, June 25, 2009

Field Camp, Part 3

I'm not going to explain much here, other than these parts of the course were for tectonic geomorphology and metamorphic field mapping. Again, this is all in southwestern Montana.Well, go figure. Geology Field Camp may be scheduled for May and June, except that in Southwest Montana, it is still "early spring". So, we had to cancel our field work that day.

Finally, nice weather! This is actually the day before the photo in the snow was taken. Here we are looking at a beautifully crossbedded tuffaceous channel complex within the Anderson Ranch Member of the Mio-Pliocene Sixmile Creek Formation.

Closeup of the crossbedding.

Some geology students attempting to cross a barb-wire fence crossing over the creek, which was overflowing a bit.

Geology students looking at Proterozoic metamorphic rocks in the lower Madison Valley, near Ennis, Montana. The beautiful Madison range is in the background.

Students taking strike and dips off of foliation within Proterozoic phyllite.

The magnificent Madison Range.

Some more of that phyllite.

Students during the final project, at Frying Pan Gulch, marching off into bad weather.

Wednesday, June 24, 2009

Field Camp, Part 2: Yellowstone NP

The igneous geology portion of field camp naturally brought us to Yellowstone National Park, one of the largest 'supervolcanoes' on earth. Yellowstone is a bimodal volcanic center, and erupts both felsic (Feldspar/Silica rich) Rhyolitic lava and mafic (Magnesium/Iron rich) Basaltic lava. Yellowstone National Park is situated within several nested calderas; each of these calderas formed after an eruption. The shallow (5km deep) magma chamber lost so much magma during each eruption that the earth's crust above the chamber collapses into the void. The caldera has since been filled with lava flows. The fractures and faults within the caldera allows for the incredible hydrothermal features within the park to occur.
Professor Colin Shaw explaining the classification scheme for igneous rocks using the infamous tertiary diagram.

Upper Yellowstone Falls.

Fountain Paint Pots, easily my favorite feature in the entire park.

Another paint pot.

Old Faithful Geyser, in the Upper Geyser Basin.

Lecturing at the Duck Lake overlook, the site of a huge hydrothermal explosion. Duck Lake is the explosion crater, and has a ring shaped hill around it, which is the ejecta blanket.

Mud volcano! Similar to the paint pots in several regards. The mud cinder cone here used to be over 40' high if I remember correctly.

Tuesday, June 23, 2009

Acid preparation, Part 2

I'm trying the delayed posting utility, so we'll see how this works when I'm done with my road trip.

Here are some more photos of the acid preparation experiment I tried last month. I shouldn't say 'tried' - because this succeeded beautifully. The jaw took about 8 days of acid bathing to completely remove all of the nodule. It did take about 3 gallons of vinegar (3.2 or 3.5 % Acetic Acid, if I remember correctly), which made for a grand total of $6 - definitely worth it, especially considering that there aren't any tool marks now, and I didn't really have to lift a finger. All this took was checking it daily, and replacing the vinegar after each 'batch' had been used up, so to speak (can you tell I didn't do well in chemistry?).
Photo of the specimen after 140 hours of acid preparation.

In any event, I am extremely happy because many fossils from this locality occur in nodules, and they are all of this same sediment with calcitic cement. I'll be at this locality in three days, so hopefully this time I'll find a skull or something else really neat.


Photo of the finished specimen after 200 hours (8 days) of acid preparation.

Monday, June 22, 2009

New skeletal drawing: Acrophoca longirostris

Hey all,

Here's a new drawing I was able to complete on one of my days off between Geology Field Camp projects. It's a skeletal drawing of Acrophoca longirostris, a very strange pinniped from the early Pliocene Pisco Formation of Peru (as well as from Chile; Walsh and Naish 2002). Acrophoca is a Monachine true seal (family Phocidae), and as stated above, is known from the early Pliocene of the Southeast Pacific. According to the phylogeny of Demere et al. 2003, Acrophoca is the sister taxon of the fearsome Leopard seal, Hydrurga leptonyx. Acrophoca was originally named by Muizon (1981). The skeleton I drew this from can be seen on display at the USNM. Ordinarily I'd give more information, but I need to pack up for my road trip.



Demere, T.A., A. Berta and P.J. Adam. 2003. Pinnipedimorph evolutionary biogeography. Bulletin of the American Museum of Natural History 13:32-76.

C. Muizon. 1981. Les vertebres fossiles de la Formation Pisco (Perou). Premiere parti: Deux nouveaux Monachina (Phocidae, Mammalia) du Pliocene de Sud-Sacaco. Recherche sur les grandes civilisations Memoire 6:1-150

Walsh, S. A. & Naish, D. 2002. Fossil seals from late Neogene deposits in South America: a new pinniped (Carnivora, Mammalia) assemblage from Chile. Palaeontology 45: 821-842.