Saturday, March 30, 2013

GSA Southeastern Section Meeting 2013

Just a week and a half ago (March 20-21, 2013) was the 62nd Annual Meeting of the Geological Society Southeastern Section, held in San Juan, Puerto Rico. This two day meeting was a great venue, not only to see some interesting presentations, but was also an opportunity to meet colleagues I had not seen in a while. One of the sessions during the first day was chaired by my friend Alvin Bonilla-Rodríguez of the University of Kansas, and myself. The aim of the session, titled: Multidisciplinary Approaches to Caribbean Stratigraphy and Paleontology, was to find out what our colleagues are up to these days. It was both our first time chairing a session, so we were both a little nervous, but I think it went pretty well. We had a great set of talks as well as poster presentations. Overall it was a fantastic meeting, hat-tip to the organizers for doing such a great job!

The title slide of my GSA talk. 

Of course, going to Puerto Rico for a meeting also meant I would stick around for a few days more.
And so I did. It was time to see my family, but also go to the field and revisit some localities.

Friday after the meeting I returned once again to my favorite early Oligocene locality (see previous posts here, here and here). It hasn't rain a lot in Puerto Rico lately, so the exposure was even better as this locality is exposed along the banks of a river. This gave me the opportunity to spend the morning measuring and describing in detail the main fossiliferous section.
The lowermost marine units was remarkable for the presence of the clam Lucina collazoensis (you can see several of them near the center of the picture). 
Overall, the sequence consists of alternating terrestrial and shallow marine horizons. It is in one of those marine horizons where I have collected several fossil vertebrates, including side-neck turtles, sirenians and rodents among others.

The main part of the section, you can see the terrestrial (brownish-redish units) and the marine (grayish units).
Of course, this wasn't the only day I went to the field. The next day I set out to Ponce, in the southern coast of Puerto Rico, where I will meet with colleagues from the Florida Museum of Natural History, as well as others interested in seeing Oligocene and Miocene marine deposits in that area. It was sort of an unofficial post-meeting field trip.

Our first stop in Ponce, where early Oligocene marine deposits are exposed.
Some of the fossils found at this locality. Left, some crinoid stem fragments. Crinoids were once inhabitants of shallow seas, but since the end of the Paleozoic, they are more typical of deeper settings. Right, a shark tooth, probably a carcharhinid. 
After spending a couple of hours at this locality we were ready to move on to the next outcrop. Unfortunately, my field vehicle would not start, and had to get towed back home.
My field vehicle, acting up...
The others, went on (we were on three vehicles), hopefully they found interesting fossils.

I'm back in Panama (it was a very short trip to PR). So stay tuned for upcoming entries on the geology and paleontology of this beautiful country.

Saturday, March 16, 2013

Return to Panama

It has already been nearly two years since the first time I came to Panama as part of a team led by Nick Pyenson and Aaron O’Dea to collect a fossil odontocete. Now I’m back in this lovely country as part of my postdoctoral research in the Florida Museum of Natural History PCP-PIRE program. This is part of a large collaborative project with several institutions in Panama and in the US, including the Smithsonian Tropical Research Institute (STRI).
A view of the sky from the STRI facilities in Ancón, before we headed out to the field.

Part of what I’ll be doing is to collect fossils and stratigraphic data from outcrops along the Panama Canal*, as well as other sites in the country. The expansion of the canal has made available a number of new cuts, which offer new information on the stratigraphy, flora and fauna and formation of the Isthmus of Panama. Even though I’ll be more focused on studying the marine vertebrate fauna, the terrestrial fauna is very interesting so I will be helping with those as well.
Outcrop of the Cucaracha Formation along the Panama Canal.

As soon as the second day I was here we (a team of interns led by my senior cohort Aaron Wood and Pedro Monarrez) set out to the field. We visited a locality of the early Miocene Cucaracha Formation where a series of fluvial deposits are exposed. In addition to the interesting geology at this locality, we found several fossils of terrestrial vertebrates as well as crocs towards the top of the section. So much that we return on the next day to look for more.
My first find, a protoceratid molar. These were part of a deer-like group of artiodactyls, best known for having horn(s) sticking out of their snouts. 

Stay tuned for more posts, as I’ll be spending a lot of time here.

*Access to this and all other paleontological localities along the canal brought to you thanks to the courtesy of the Panama Canal Authority (ACP).