Thursday, May 26, 2011

Niobrara Trip #1 complete

Sorry it's been so long since the last blog post. Strange combination of field work and Chrome barfing the interface with Blogger on my end. Got it fixed now though. Hopefully.
Dumpy doesn't know if the sign is for the road or her

We went out last week on our first collection trip in the Niobrara Chalk of western Kansas last week, and had some great success. We went out with a class from the University of Tennessee Martin, and the students were a great help in covering outcrops that we hadn't looked at for a few years. The first recoverable item was found before the students had even arrived: a partial large Saurodon leanus skull, RMDRC 11-020. It was collected on a small knob really close to the surface with a plant on top. Roots did a number on it, but it is restorable as a plaque mount.

How many people does it take to jacket a mosasaur?
The second day of scouting with the whole compliment of people resulted in one of the students discovering a mosasaur skull, neck and partial torso coming out snout first of an outcrop low in the chalk (around MU 5), RMDRC 11-001. It looks to be a specimen of Platecarpus planifrons, with what appeared in the field as possible intraspecific bite marks across the snout. Ouch.
Standard TPI field pose

The next day we shifted over a section to the east and hit some outcrops that I had never scouted. The student that found the mosasaur managed to find a decent nearly complete Cimolichthys nepaholica, RMDRC 11-004, and not 30 yards away, an extremely large (9 foot long) Ichthyodectes ctenodon, RMDRC 11-018. Both animals were recovered. The Cimolichthys will be used in our 3D restoration project (which is ongoing) and the Ichthyodectes will be used to enhance our current 3D cast.


Perimitering the Cimolichthys before jacketing



The best part about it was that I was able to collect a few specimens for my pet research projects, including some Spinaptychus jaws, RMDRC 11-005-007 and a partial Martinichthys brevis skull, RMDRC 11-003. These rare little fish only appear to occur between MU 4 and MU 6 in the chalk, and material is pretty scarce, including skulls. Hooray for more data points!

Martinichthys snout!

Friday, May 6, 2011

Surprise jacket contents

Sometimes a bit of exploratory prep shows everything in the jacket. Sometimes there is more fun stuff buried deeper. We came across UTC's syncervical the other day. Sorta smooshed but still more or less recognizable. Hooray!

Tuesday, April 19, 2011

About halfway there

Jeez, UTC is very challenging prep. Slowly working through the very fragmented nature of the bone, but luckily the matrix is also fairly soft. We are, however, using a lot of consolidants to keep everything together. It's really interesting to see how things are taking shape now that we have prepared pieces that are starting to fit together, such as the right front arm. Below is a pic of the coracoid, humerus, ulna, meetacarpal and phalanx that we have finished.

Right arm taking shape, scapula still being prepared
After taking measurements and scaling them to the AMNH's Centrosaurus skeleton, it appears that our critter will be a hair over 6m long (19.5 feet) if it were complete.

Mid caudal... big, but no transverse processes


We're always working on a bunch of different things at the same time, so just for Saurian, we'd like to announce we've started baby steps towards working on our Daspletosaurus Pete III again. Jacob is working on a block that had a fibula, distal tarsal, and 5 articulated mid-caudal vertebrae in it. Hopefully by the end of the day tomorrow everything will be finished, and that's one more big jacket off of the shelf!
Pretty fibula!

Tuesday, April 12, 2011

Centrosaur prep binge

We begin week #2 of our prep efforts with renewed energy! The more we work on it, the more neat stuff we find. Case in point the jacket labelled "?tibia" turns out to be a complete right humerus, with a total length of 70cm. An ulna and fibula have also turned up, and field sketches seem to show a femur. This appears to be a fairly large centrosaur, approaching the size of our Triceratops prorsus skeleton "Gundy". If any of you researchers have good PDF references on centrosaurs, please contact me, I don't have library access so modern papers are relatively difficult to come by.

Right humerus

Ulna!

Other jackets are showing they have much more in them than what was recorded in the field notes. The jacket below looks to contain a predentary, several ribs, and a least one strange unknown (as of yet) element. We should know soon though!

All kinds of stuff in there.

Monday, April 4, 2011

Horn-faces and prep

We restarted work today on a dinosaur project that I'm actually pretty excited about. With the new discoveries from Utah, it looks more and more like the ceratopsian dinos of the Campanian are very specific to geographical area, in addition to stratigraphic level. For us working in the Judith River that means that you can maybe find Avaceratops and Monoclonius, according to the now seemingly dated conventional wisdom. Except that a new specimen of Ceratops montanus was recently discovered near our dig areas. And we've found things that look a heck of a lot like Anchiceratops. And Styracosaurus. And bits of a big honkin thing that looks a bit like the newly described Kosmoceratops. Oops. What a mess.

Dig site at the end of excavatoion
Typical jacket showing typical not falling down hill bone


The critter we're working on now is a centrosaurine nicknamed "UTC". It was discovered in 2004, and has sat on our shelves for much of the in-between time. It's time to knock out the prep. Unfortunately the specimen was discovered coming out skull first, with those parts slumping slowly downhill. It's going to be an interesting challenge getting it back together.
oooh epoccipitals!

The parts that we have are pretty interesting though, and as prep continues we may be able to get a good idea of what critter we have. Heck, based on the explosion of ceratiopsian discoveries in the past few years (and how most researchers avoid the Judith River Formation like the plague), there's even the possibility that this animal is a new species. We'll keep you updated on the progress as more bones get prepared.

Tuesday, March 22, 2011

Jonesing for mosasaurs

It's starting to feel a lot like springtime, which for us usually means trips to western Kansas to our Niobrara chalk localities. We haven't made it out yet (still waiting on that first downpour to wash the winter fluff off of the rocks... it may be a while with this drought) so instead I'll write a bit about a mosasaur that is near and dear to me.
Starting the hole

RMDRC 06-009 "Cap'n Chuck" was the first mosasaur I ever found. It's a specimen of Platecarpus "ictericus" (sorry Takuya, haven't made the species switch yet) from the upper chalk of Logan County, about 83 million years old. I spotted a single dorsal vertebra sticking out of a vertical gully wall, about 12 feet above the gully bottom. Don't ask what I was doing looking up there. My boss, Mike, loaded Jacob and I into the bucket of the bobcat and lifted us up to see if there was anything else there besides the single vertebra. Yep! we discovered the back of the skull, but since it was late October and in the low 50s (with drizzle coming in and lots of wind) we decided to secure the site till the next spring.


Jack-hammerin
In April of 2007 we returned, with a fancy new mini jackhammer that Mike had bought over the winter. Holy moly that thing saved us a lot of time.



We made this big of a hole in 3 days

Do you see the skull?
It turns out field mapping in the chalk is kind of a tough thing to do. The chalk gets all over everything and generally makes life miserable. It's best to save it for the lab. The skeleton was preserved very well, missing the end of the tail. Quick measurements of elements give us a total length of about 23 feet, which is pretty dang big for a Platecarpus.
Main jacket flipped and prepared. Things are much easier to see.

Once show-prepped in the lab it was decided that Cap'n Chuck was complete enough to restore in 3d (most exploded skulls are good candidates, there's less crushing distortion). That meant pulling every individual bone out of the jacket and cleaning it completely. This enabled us to get a good look at some rare parts like the interclavicle and ear cartilages. Hopefully we'll be able to start restoration sooner or later!

Laid back

Wednesday, March 16, 2011

Small projects

Yep we all have them. In addition to the decades of prep backlog of big, complete and interesting specimens there is always that nagging pile of individual bones and small specimens that gets collected then sits as priority number 12 on the shelf. Sometimes it's a good organizational effort (and therapy) to get these things knocked off the to-do list. Plus it frees up a bit of space for the next season's collecting efforts (which should begin any week now, hopefully.
You ever get the feeling you're being watched?

This past summer during beer week in Montana I found a small shard of tyrannosaur tooth sticking out of a lag deposit. I suggested to one of our guests, Terri, that she could spend some time excavating it. Turns out she discovered that the tooth was still connected to a chunk of jaw. Unfortunately digging it out was a bit of a chore since the sandstone got really hard really quickly. It did clean up nicely though, and will be going on display sometime today.

Tyrannosaur maxilla and tooth

Some progress is being made on Pete III, our challenging Daspletosaurus torosus, also from Montana. This huge 70 pound monstrosity of a jacket contained just one spindly rib. That and lots of sandstone. Whatever, it's off the shelf now and nearly in the clean room.
There's the rib!

We're not all about preparing partial dinosaur bones though. This Pteranodon sternbergi metacarpal was pulled from the lower chalk in western Kansas a few years back. Should have been prepared years ago.
Isolated bones are so pretty