Tuesday, July 30, 2013

An Embarrassment of Riches

5th Update - an Embarrassment of Riches

This report covers from June 18th to July 22nd. 

We continue to uncover many more bones in the block. Most of them are relatively large, and many are touching each other. While this makes it difficult to remove them totally, we have such an embarrassment of riches! First of all, we have removed two touching vertebrae (centrums) one of which still have part of the neural arch attached. 

There are another 3 centrums underneath those, and a wonderful shaped bone that may be part of either a hind limb or a front limb:

We have a large curved bone with a hole in it. I'm betting it is part of the skull. 

There is another large curved bone with a rougher surface (no, it's not preparation mistakes). Possibly another part of the skull.

I uncovered the scapula mentioned in the previous entry. This will be definitely hard to remove, as there appears to be another long arm bone immediately behind it. The long bone has the typical hollow end we've come to expect, caused by the animal being immature.

We have other animals as well - a wealth of Nautiloids (Chambered Nautilus). In this small part of the first block we have already identified 5 of them, the largest about 11cm across. This is an high concentration - generally Nautiloids are rare in the fossil record. My theory is that they were scavenging the carcass as it lay on the bottom, and all were buried together in a landslide (turbidite flow)

Here's one of the other volunteers at OMSI - Jerry Dodson. You can tell our working conditions are just fine - casual attire! Jerry's a retired accountant, and I'm a retired engineer . You don't have to be a graduate paleontologist to learn to prepare fossils!

Last of all, here's a new display case to display the larger bones as they have been prepared. We'll keep adding them as they are ready. Smaller fragments will  stay in plastic bags so they don't get lost. 

Friday, July 26, 2013

4th Update - Bernie's Got Teeth!!

Bernie’s got Teeth!!! – and other finds

This report covers the period from May 18th to June 17th, 2013
The highlight of this period, as noted above, is that a fragment of jaw with imbedded teeth has been found! This means that we do have some of Bernie’s skull, even if in fragments, and the teeth are certainly diagnostic.  The teeth are imbedded in their own individual sockets . This dental structure is termed Ichthyosaur Thecodont (R Motani) . We don’t know if the teeth are fused to the jawbone at the bottom or not – it will take an X-ray or CAT scan to determine that.. This is unusual for Ichthyosaurs, where the teeth are usually imbedded in a long groove along the jawbones especially for all Jurassic and Cretaceous Ichthyosaurs. The broken face of the bone was actually exposed on the surface of the concretion, so we know it’s long gone. In the picture below, the left side of the jaw is the distal end of the jaw – end furthest away from the skull.

Having the teeth in individual sockets limits Bernie’s families to the known Cymbospondylus and Shonisaurus or an unknown lineage. Both of these are found in Triassic Nevada though the Cymbospondylus has not been found in the Carnian age, which Bernie’s formation is dated.

One side of the jaw has some funny-looking bone, rather porous and irregular. It may be some preserved cartilage or who knows – old injury site perhaps? 
Other great finds worked on this period is a possible Graphaea, or oyster-like animal. However, this shell has two ‘wing’ projections out the side where all the descriptions of Graphaea do not show these. Perhaps it's a pearl oyster instead - Dr Retallak at the U of Oregon gave this suggestion - Your bivalve is not Gryphaea, but more like Pteroperna cf. P. plana (a common species in the Pliensbachian Robertson Formation)

We are starting to work out this thin blade of bone. Further work (see the next entry) shows this is a very complete scapula. The notches on the edge are from some bone that broke off with the covering rock, which came away in one piece. We have them & will re-glue them back on. Number one rule in Paleontology - KEEP ALL THE PIECES!!!!!
Further work (see next post) suggests this may be part of the skull - 

Last, we have a great Nautiloid starting to be removed. It’s over 11 cm in diameter, and one side is apparently uncrushed. It’s going to be beautiful:

It’s hard to get a full picture as it’s very close to one of the shoulder girdle bones shown above This block contains three other incomplete Nautiloids, and part of another one that could be complete – the rest is in another block. I still think the Nautiloids were eating Bernie’s carcass when they were all buried – this may explain why we have so many in one small spot.

More to come……..

Thursday, July 11, 2013

Fourth post - second update on the preparation

Preparation update, Bernie the Ichthyosaur, March 16, 2013.

Progress on preparing Bernie the Ichthyosaur continues apace. Most of the work this past month focused on preparing a Coracoid that will probably be important in classifying the animal. The coracoid was in poor shape, being split between three separate blocks of rock. The blade had been split down the middle, through the largest plane of the blade, leaving two thin sections on different rocks that individually were too thin to prepare.
   In addition, the thicker section of the Glenoid side of the coracoid (the joint to Humerus) was on a third rock. Many small bones were uncovered during the excavation process, including two neural arches and parts of centrums.  Eventually, all three sections of the coricoid were partially prepared and glued back together with a filler of epoxy to make up for material lost during breakage. The exterior of the bone was then cleanly prepared, restoring it to the original dimensions. Only a small amount of distortion in the finished bone is noted. One small spine was left on the surface as it’s too delicate to prep out. This was a very satisfying job.
A second important bone, a humerus, is currently being prepped. It too was found in three rocks. The proximal end (end nearest to the body) has been prepped, as it was almost entirely free anyway. The distal end (end away from the body) is being worked out. It is adjacent to a rib bone, and I may leave them joined on one block of rock instead of separated.  [ I did end up separating them] I think I can recover more of the curved end of the rib from another block of rock. 
Both ends of the humerus have a conical hollow in it, without any fill. I left the matrix (surrounding rock) in them to support the thin edge of the bone. I suspect it had an extensive cartilage fill, and was probably not ossified. Several other arm bones that are not totally prepped out yet show the same condition. Perhaps this was a young animal? Also of note is there there is no anterior flange – the shaft is completely round and symmetrical. I haven't found any species of Ichthyosaur where the arm bones are not flattened - stranger and stranger! 

Sincerely, Gregory Carr

Third post - first update on the Preparation

First Report on the Preparation of Bernie at OMSI (Oregon Museum of Science and Industry)
Greg Carr Feb 2, 2013

So far, I have spent portions of 8 volunteer days working on Bernie at the Preparation lab at OMSI. I’m the only one working on it so far, and I don’t know what Sue Wu (the director of the Earth Sciences section)  has planned for the other volunteers. So far I’ve completely prepped out one block about the size of two decks of cards that had a lot of bones visible on it.  I also worked on the adjoining block that has a Coracoid or Scapula 
on it. So far I have  recovered parts of 4 vertebrae, one long bone, one rib, one chewed up end of a long bone, one very small spine that may be from a sea urchin, three tiny ammonites, a couple of decent brachiopods, and pieces of several broken bones of unknown sources. The blocks are so rich that you have to be very careful – just digging into them to free up a bone will uncover other bones, ad infinitum.

One thing is puzzling – I think we will have too many ‘Long Bones’ to be a Shastasorous – they only had 4 per animal, and I think I’ve already accounted for 3 full bones and 3 ends of others. So maybe it’s a different, more primitive type from the middle or early Triassic. That would upset the dating of the Vester formation/Brisbois member. Or perhaps it’s a new species (Oh please, please!!)>   Or maybe there is more than one body present. Anyway, we’ll know more in about 6 months when we get the Coracoid/Scapula and the arm bone associated with it out & prepped& sent off for speciation.

Sincerely, Greg Carr

Tuesday, July 2, 2013

Second Post - Finding Bernie

Geologic  Background:

 In the Triassic era most of Oregon was actually small islands and fringing reefs similar to the Molucca sea or Papua New Guinea of present time. The seas were dominated by Ammonites instead of fish, and marine reptiles like Ichthyosaurs were abundant. The area now referred to as the Suplee/Izee inlier was a vast delta and estuary, a basin being filled with mud, sands and rocks being washed in from surrounding islands. These islands are now known as the Baker Terrane; the surrounding reefs are the Grindstone Terrane, and the basin deposits are the Izee Terrane.  The whole area was located in the Western pacific ocean, south around the latitude of Mexico or California, hundreds of miles away from the mainland of North America. 
This Ichthyosaur (Bernie) came from the late Triassic time, about 220 million years ago. The formation is named the Brisbois member of the Vester formation.  This was the Carnian period, when the basin between islands was being filled with stones and sands alternating with quieter periods where mud filled the still waters. There were turbidite flows (to be explained later) After Bernie died,  scavengers began to eat it, as tiny ammonites have been found next to the bones. A landslide occurred, and the body was buried in the sandy deposits. This preserved the bones as more sand and mud piled on top of them. 
Eventually, these sea deposits hardened into rocks. They were not carried deep into the earth, as they show no evidence of metamorphism. Instead, they remained at shallow depths as the section of Earth’s crust was carried as a block north and west to eventually come to rest alongside the North American continent during the Cretaceous time. Eventually the thinner, more recent volcanic rocks covering them were eroded away, exposing this fascinating window into deep time.

Finding the bones:

The Izee/Suplee inlier has been known to contain some of Oregon’s oldest rocks since early in the 20th century. It was extensively surveyed in the 1950’s, and has been a favorite area for fossil hunters ever since. A true understanding of the area’s past has been slow to emerge, as it is very complicated and exotic. Small areas of rocks ranging from Devonian (400 - 360 million years old) to the Cretaceous (85 million years old) are all exposed, often jumbled and mixed, never straight-forward. Active exploration and investigations to determine the exact history are still on-going, and how it formed is an area of active scientific investigation. All in all, a wonderful place to explore.

In the summer of 2011 my daughter Gloria Carr and I were on a field trip to the Suplee area to collect specimens of Jurassic plant materials from the Trowbridge formation. I first discovered these plant materials in 2008 and they are actively being studied by professors at Oregon State. She needed a field trip for a geology class, and what better place to go than this? Along the way, we stopped at a road cut near the intersection of the Suplee/Izee road and the Weberg road in the eastern part of Crook County. I had found a few ammonites here the previous year (2010) and thought we could find some more. We parked on the shoulder and walked across to the slope. Almost immediately, I picked up a nautiloid fossil, and Gloria picked up something else. “It’s round, but it’s not an ammonite. What is it, dad?”  I looked at it closely, and recognized it as bone. “It’s bone, bone!” and we both got excited(bone is very rare, much more rare than ammonites or other shells).  We then searched around, finding some more small rocks containing bone fragments. Working uphill, we found the main concretion containing bone fragments on the surface of the rock, and we knew we had found the source.  We could identify what looked like ribs, backbones and maybe paddle bones, so we knew the skeleton was disarticulated (broken up, not in order).  We took the loose stuff from the slope, and marked the location on a map & on the GPS.  We didn’t try to excavate the entire block, so as to not draw attention to our find – plus it was plainly too large for the two of us to handle. Although we were very excited, we continued on to the Jurassic plant material site to get the necessary field trip work done. 
Pictures of Gloria and myself on 
the day of the find. 

Doing the paperwork:

Part of correct fossil hunting is do things right. Fossils belong to the landowner, not the finder. If it’s BLM or National Forest they belong to the US government; if private land, the landowner; if county or state land, they belong to those government bodies. In this case, the fossil was on the right-of-way of a Crook county road. Who did it belong to?  I worked with Crook county authorities for a number of months to determine that that section of road cut was owned by the adjoining landowner, not the county. I found out who the owner was – Gene and Miriam Bernard, and old ranching family and one of the original homestead families of the area. I got their permission to excavate the fossil, and they would donate it to the University of Oregon as part of the Condon collection. Perhaps we could have asked to keep it – but why? We certainly did not have the thousands of hours it will take to properly prepare the fossil, and it rightfully belongs to the people of Oregon. We just found it.

Along with permission to excavate, we needed to work with Crook County to get a permit to perform the excavation in the road right-of-way. Penny Keller, the Crook county Roadmaster, was extremely supportive (thanks, Penny!) and helped us determine the proper safety flagging and warning cones as well as helping fill out the actual permit.

The recovery excavation:

A little more background: my family is a member of NARG, www.nargpaleo.org the North America Research Group, a fossil-oriented club based in Hillsboro, Oregon. We wanted the NARG group to excavate the fossil for a number of reasons. First, it would be a big job and we would need more than my family to do it. Second, it would be a wonderful opportunity for the club members to help recover one of the ’big three’ – Plesiosaur, Crocodile, Ichthyosaur – that club members have found. Third – this fossil is important and needs to be shared with the larger community.

The NARG group decided to recover the specimen over Memorial Day, 2012. A few weeks before the date, one of the landowners, Gene Bernard, was tragically killed in a traffic accident on highway 26 near Vale, Or. His widow Miriam re-affirmed that we could continue to recover the specimen as planned. We decided to dedicate the specimen to Gene and name it “Bernie” in his honor.

Here's the NARG crew that excavated Bernie: 

On the appointed day, Saturday May 26th, we all met at the Weberg/Suplee road intersection and traveled to the excavation site, a few hundred yards away. Although it was cold and windy, it did not rain on us. The slope below the concretion was combed for other smaller pieces of ‘float’ that might contain bones, though few were found. Then the concretion itself was dug out, and some of it was encased in plaster to reduce breakage before movement. (Actually this didn't work real well as the plaster broke apart during the move, but it didn't matter since the move was only about 15 feet!)
 This was actually really fun – we backed the Suburban across the ditch and planted the tail into the slope below the rocks. Then we put a couple of planks on the slope and slid the large rocks directly into the back of the Suburban. 
This had to be one of the easiest transports ever – which is good, since the large blocks weigh several hundred pounds each.  After Bernie was safely in the Suburban, we cleaned up the excavation site and headed off to a lock Forest Service Campground (Sugar Creek) to hold a celebration potluck dinner. All - in - all a very satisfying day. 

After the Excavation:

Bernie was transported safely to Tigard Oregon  in the back of my Suburban. We call it the “Tank” for good reason – a ton of rocks in it and it still travels well. The bones were re-assembled in approximate order and a small section which had crumbled during the excavation was pieced together. The pieces were labeled & mapped before taking it to OMSI for preparation.  Here we are in my garage with Gloria for scale:  The foil wrapping is used to hold pieces together before covering them with plaster. The foil also provides a barrier to keep the plaster off the fossil, making it easier to prepare. 

Third post - off to OMSI (Oregon Museum of Science and Industry) for preparation

First post - Background and Introduction

This blog is about finding, preparing and displaying Oregon's oldest and most complete Ichthyosaur (Fish-Lizard). Along the way, I'll include thoughts about paleontology, life and death from a fossil viewpoint, fossil hunting as a hobby, and getting serious on the science end of things. The story started about 230 million years ago in the warm seas around semi-tropical islands and is still continuing in the Central-Oregon  high desert and temperate metropolitan Willamette Valley. I hope you enjoy your visit.

Sincerely, Gregory Carr