Wednesday, July 28, 2010

More Cephalopod Fun

Throwing a bone to the invertebrate guys out there, here's new images of RMDRC 10-018 Spinaptychus sp. that yours truly found earlier this spring in Gove Co., Kansas. Ammonite remains are fairly rare in the chalk since the aragonitic shells do not readily preserve. These jaw parts however are calcitic in nature, and are occasionally found. We lent this specimen to Neal Larson of Black Hills Institute for detailed preparation and a bit of restoration before molding. He and his staff did an absolutely phenomenal job. Thanks again, neal!

The specimen is fairly large at over 5 inches wide, 4 inches long. The next project is determining what ammonite this specimen belongs to. Hopefully a paper will be coming out soon!

Monday, July 12, 2010

The Disassembly of Dillon

Back in April of this year Paleotech Jacob Jett discovered a small mosasaur in the upper Niobrara Chalk of Logan County, Kansas. This critter, a Platecarpus (RMDRC 10-007) consisted of a skull and 5 cervical vertebrae. Part of the upper jaws were exposed at the surface, and there was extensive calciteAbove, Jacob works on preliminary excavation immediately after locating the specimen. Luckily there was little present in the way of overburden.
A few hours later, Jacob has found the perimeter of the specimen (he finally discovered something, so I went to search other areas of the outcrop, finding the big Clidastes Tony II RMDRC 10-008). The entire exposed area will be covered with a plaster and burlap jacket to transport back to the lab. Unfortunately, after the jacket was made, the area was hit with torrential rains (6 inches in 24 hours) and we were not able to get back to the jacket to bring it home. It had to sit out exposed to the elements for 2 weeks.
The jacket was "show prepped" (prepared to expose what is present) once it returned to the lab. As you can see, most of the skull is there, missing only parts of the left maxilla and for some strange reason, the braincase! I am currently in the process of getting these heavily concreted bones separated so that Dillon can be reassembled as a 3d skull and neck mount. As you can guess, it is a time-consuming and delicate process, and the results will be shown in the next blog update.