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

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