Oral Presentations
A SMALL SCALE, LOW-BUDGET, HYDRO-EFFICIENT SCREEN WASHING METHOD: THE “MINI-SCREENER”
— TEMME IV, Thomas, Intermountain Paleo-Consulting, Vernal, UT, USA; MASTERS, Simon, Â Intermountain Paleo-Consulting, Vernal, UT, USA; SANDAU, Stephen, Intermountain Paleo-Consulting, Vernal, UT, USA
Screen washing is an invaluable technique for revealing scientifically significant microfossils that are otherwise undetectable and inaccessible, yet in most instances it is a large scale, outdoor endeavor restricted to water access and favorable weather. The Mini-Screener is a compact and economic alternative that can be utilized indoors throughout the year. The Mini-Screener is a simple apparatus that mimics the fundamental processes of conventional bulky screen washing, utilizing inexpensive and readily available supplies that can be operated in small spaces and simultaneously conserve water. The device is comprised of a fine-gauge mesh strainer, a standard wash basin, a stainless steel mesh strainer basket (which is suspended in the wash basin), a 20 gallon aquarium air pump (or larger), and associated plastic tubing. The tubing is attached to underside of mesh strainer basket to aerate the water bath which prevents sludge buildup in the suspended strainer basket. Microfossil bearing rock or sediment which readily breaks down in water is placed in the mesh basket and immersed in the wash basin and soaked. The percolating water speeds up the brake-down time and reduces the matrix sufficiently to allow for the finer particles and microfossil elements to collect at the bottom of the wash basin. The collected material is then poured and strained through the fine-gauge, mesh, kitchen strainer and the concentrate is collected and dried for analysis. This method allows for low budget, hydro-efficient screen washing when traditional large scale methods are unable to be performed. The Mini- Screener is also an easily modifiable system which can utilize different solutions for soaking, varying screen gauges, and diverse methods of agitating the material.
DELICATE FOSSIL SKULLS FROM A RICH HOLOCENE SITE: WHICH TECHNIQUES WORKED BEST FOR PREPARATION, DISPLAY, AND T RANSPORTATION
— FITZGERALD, Erin, University of Chicago, Chicago, IL, USA
Fossil vertebrates, including humans, recovered at a Holocene site in the Sahara were extremely fragile and preserved in a loose sandy matrix. Due to the quantity of specimens excavated, and the range of preservation, a variety of techniques were used. During preparation, most skulls required special attention so as not to lose associations; others required extensive reconstruction. Some skulls required the development of a new technique that would allow researchers the option of opening the cranial vault for access to the interior of the specimen. The pieces were mounted individually, on plaster cradles, which contribute to the practice of conservation by limiting the use of glues. After preparation, the best preserved skulls were fitted to custom mounts, which assisted photography and research as well as readying the specimens for display. After their completion, skulls and any associated bones and holders were placed in custom fitted foam-lined cases for safe storage, easy access, and transportation. These skulls have been safely transported for CT scanning and presentations, and will be ready for transport back to Niger, their country of origin.
JACKETING THE DESERT SANDS
—FOX, Marilyn, Yale Peabody Museum of Natural History, New Haven, CT, USA; BIBI, Faysal, Yale University, New Haven, CT, USA; HILL, Andrew, Yale University, New Haven, CT, USA
In December of 2007, a team from the Yale Peabody Museum of Natural History traveled to Abu Dhabi, United Arab Emirates, to work in conjunction with the Abu Dhabi Authority for Culture and Heritage. The team prospected in Miocene age deposits of the Baynunah Formation along the Persian Gulf coast, and discovered and excavated specimens that included an elephantid jaw and a partial ratite, while a crocodilian skeleton remains for future excavation. While Abu Dhabi is truly a sand desert, coastal sites are quite humid, slowing plaster drying times significantly. The excavation of bone that was fractured apart by evaporites and weathering, lying in soft and loose sand, presented several issues that were considerably different from those presented by the more usual siltstones or mudstones. The typical pedestal method for jacketing is less than successful in such sand, because the partially capped jackets usually slump prior to flipping. One answer is to heavily consolidate the specimen and surrounding sand, but again, due to the humidity, consolidant drying time is slowed. Overzealous consolidation in the field, furthermore, creates later challenges to preparation. Butvar B76 or PVA B15 in acetone, as less viscous consolidants, proved to be more appropriate than thin Paraloid B72 in acetone, while an attempt to use Aquazol 200 in water proved ineffective. Another technique is to jacket far more of the matrix than is needed for the stability of the specimen and cut away the extraneous plaster and matrix after the jacket is flipped over. This paper will discuss some of the logistics involved with this and other international fieldwork, as well as considerations of methods and materials for consolidation and excavation of fragile specimens in loose sands.
ON THE USE OF PLASTIC AIR CONDITIONER FILTER MEDIA IN PLASTER JACKETS FOR FOSSIL COLLECTING
—CAVIGELLI, Jean-Pierre, Tate Geological Museum, Casper, WY, USA
The use of plaster jackets has long been standard practice in the collection of fossil vertebrates. Since the nineteenth century burlap dipped into plaster has been used to make plaster jackets. These provide strength and rigidity to fragile specimens. Several creative alternatives to plaster jackets have been used recently, most commonly pre-plastered medical bandages, and aluminum foil and duct tape. Several years ago, at the email urging of Russ McCarty, some collectors started using plastic air conditioning media instead of burlap in field jackets. Randomly oriented polyester strands make up these filters, leaving a lot of air space between them. Plaster easily takes the place of the air, while the plastic provides multidirectional strength. Using AC filter media instead of plaster is a quick and efficient way to make strong plaster jackets for fossils. These jackets are easier to open, thereby reducing the chances of accidentally scarring the fossils inside. The Tate Museum has tried this technique now for several field seasons with great success. Two of the plaster jackets were multi-ton dinosaur jackets, both of which suffered no ill effects when rolling them over. Air conditioner filter media can, of course, also be used in conjunction with burlap, depending on the situation. We encourage others to try this technique as it is quicker and easier than burlap strips. One drawback is that larger pieces of filter media saturated in plaster may tear when used due to the weight of the wet plaster. This technique may not be best for smaller specimens or for tightly packed fossils that will be jacketed individually. We have also developed a simple technique to aid in the initial opening of plaster jackets using foam swimming pool noodles.
CHALLENGE: HOW TO EXCAVATE, PREPARE, DISPLAY AND TRANSPORT DELICATE ARTICULATED FOSSILS FOUND IN UNCONSOLIDATED SAND?
— KEILLOR, Tyler, University of Chicago, Chicago, IL, USA
Recovering a diverse fossil fauna from a rich Holocene site in the Sahara of Niger proved challenging due to an unconsolidated sandy matrix. Reversible consolidants were used in the field to harden the sand, facilitating jacketing of articulated specimens. In the lab, careful preparation maintained the articulations while exposing anatomical details. Skeletons were treated as thin slabs, leaving supportive, hardened sand between ribs, for example. After carefully sealing the pores in the sand, each hardened specimen/slab was molded with silicone rubber. Lightweight and durable polyurethane casts, with embedded support stands, can be exhibited in a novel way: displayed vertically, the viewer can walk around a specimen to observe the in-situ pose of the fossil from either side. Lightweight fiberglass holders, created for both sides of each fossil specimen, provide support and permit flipping and viewing from front or back. These holders nest within custom fiberglass travel shells, which bolt together. A remarkable series of three intertwined Homo sapiens skeletons illustrate the entire prepartion process developed for this site.
A RELATIONAL DATABASE DEVELOPED AT JOHN DAY FOSSIL BEDS NATIONAL MONUMENT FOR THE PURPOSE OF MANAGING AND STANDARDIZING PREPARATION DOCUMENTATION
— SMITH, Matthew, John Day Associates, Gainesville, FL, USA
Laboratory data collection at John Day fossil Beds National Monument has traditionally been concerned with who has done what to a particular fossil, with what chemicals and tools, and how long it took a person to accomplish that task. These documents were stored as Microsoft Word documents and were difficult to compare for the purpose of quantitatively answering questions regarding fossil conservation issues. A new Microsoft Access Database has been created which helps to standardize data entry and facilitate research into the effects of long-term storage of fossil specimens in a variety of museum settings. Issues such as the interaction of fossil pH and adhesives, the effect of casting material on the longevity of molds, storage of fossil specimens with plastic casts, and the physical consequences of long term display versus collection storage on similar fossils from a single locality can now be addressed. However, the database will require the due diligence of preparators and curators over an extended period of time in order to address these questions universal to paleontology collections.
UTILIZATION OF CYCLODODECAN AS A STABILIZER DURING PREPARATION OF CRANIATA
—NIXON, Deborah, Southern Methodist University, Dallas, TX, USA; VINEYARD, Diana, Southern Methodist University, Dallas, TX, USA
The application of cyclododecan, a volatile binding medium, was utilized as a stabilizer during air scribe preparation of fossil turtle skulls. The specimens represent a new basal Eucryptodira recovered from the Early Cretaceous Glen Rose Formation Trinity Group, Texas. Four complete skulls and one partial cranium required preparation of the interior regions and the exposed neurocranial structures and foramina, respectively. Two of the four complete skulls were well preserved while two were poorly preserved, brittle, and missing bone. The skull bone was thin on the two poorly preserved specimens. The matrix consisted of dense limestone with calcite veins and thin calcite deposits between the matrix and bone. Based on the specimens representing a new taxon, preservation without loss of bone during preparation was of the utmost importance. The application of cyclododecan involved two simple steps. Step 1: melting cyclododecan crystals to a liquid state at a temperature of 130 degrees. Step 2: Applying the liquid cyclododecan utilizing a small brush. The cyclododecan cools instantly upon application. The cyclododecan was applied to a thickness of approximately 3 - 4 mm or until the cyclododecan was opaque. The skulls were then prepped using ARO air scribes to remove the matrix. Cyclododecan sublimates from a solid to a gas at room temperature, depending on thickness, within 15 – 30 days without discoloring or altering bone and leaving no residues. During the preparation process, the skulls were kept refrigerated to slow sublimation. Once the preparation was complete, the cyclododecan was allowed to sublimate off the specimens. Although air scribes, even the smaller units, can fracture delicate bone, cyclododecan used as a temporary stabilizer is essential in providing strength to the bone as well as retaining broken parts in situ so they may be permanently reattached. Preparation of the fossil turtles resulted in zero bone loss and exposure of interior skull regions that may not have been possible without damaging other areas of the skulls if cyclododecan were not utilized as a stabilizer.
FAMILY REUNION: A COMPOSITE RECONSTRUCTION OF THE TYRANNOSAURUS REX HOLOTYPE SKULL
—HOLLAND, Michael, Michael Holland Productions, Bozeman, MT, USA
In 1905, the genus Tyrannosaurus was erected in Osborne’s description of AMNH 973, a large skeleton excavated in 1902 from Hell Creek sediments in Eastern Montana. The specimen was housed in the American Museum of Natural History until 1941, when it was purchased by the Carnegie Museum of Natural History. Though about fifty percent of the skeleton is preserved, the skull is substantially incomplete, with only eight of the cranial elements present. The original 1942 fossil and plaster reconstruction of the skull crowned the skeletal mount that stood in the Carnegie Museum for over sixty years. Recently, for display in the new dinosaur exhibits at CMNH, the entire skeleton was dismantled for cleaning and remounting into a posture consistent with current science. Issues of weight, fragility, and research access necessitated using casts for the skull on the finished mount. A complete cranial reconstruction would require obtaining or fabricating the numerous missing skull elements. A curatorial decision was made to use as many casts of actual Tyrannosaurus rex fossils as possible in the new skull reconstruction. In an effort to use those elements most consistent in size and morphology with the holotype material, casts of cranial elements from five different specimens of Tyrannosaurus rex (including the holotype) were employed. The processes described here include assessment and selection of available specimen casts, modifications to chosen elements, and assembly and reconstruction to produce what is finally an anatomically accurate reconstruction of this iconic and historic holotype specimen.
WHEN THE CRADLE ROCKS: SIMPLE STRATEGIES FOR STABLE STORAGE AND SAFE USE OF PALEONTOLOGICAL COLLECTIONS
—BROWN, Gregory, University of Nebraska State Museum, Lincoln, NE, USA
Limiting the potential for damage to any museum object involves addressing all of the “agents of deterioration” recognized by conservators, but the vast majority of damage to paleontological collection objects can be attributed to a single agent: direct physical forces (gravity and applied forces) related to improper storage and handling. An irregular object placed on a flat surface exerts all of its mass on three points, imparting considerable stress to the object. If the majority of mass is born on only two of these points, the object will be both under stress and unstable (prone to motion). It is a mistake to assume that seemingly sound and robust specimens do not require proper support. For larger objects, traditional form-fitting cradles of reinforced plaster or resin relieve stress by distributing an object’s mass over an infinite number of points, however the irregular cradle itself may not assume a preferred orientation or stable resting position in storage. Addition of a cradle support system composed of blocks of expanded polyethylene foam on a rigid base of high-density Masonite provides cradle stability and isolation from vibration. Smaller objects benefit from simple polyethylene foam cradles. Proper orientation and compartmentalization in cabinet drawers limits destructive motion. It is also a mistake to assume that those who utilize our collections have the requisite skill or common sense to handle specimens safely. Formal written protocols should be provided that detail both basic and specialized handling guidelines and requirements. In addition, wise choice of primary storage orientation and use of “clam-shell” cradles can significantly lessen the need for direct handling of specimens. Well-designed storage can be both aesthetically and functionally elegant and, when combined with enforced handling protocols, can greatly reduce the forces that commonly damage our collections.
RESTORATION AND THREE-DIMENSIONAL ASSEMBLY OF A NEARLY COMPLETE, ARTICULATED EOCENE PROTOCETID WHALE SKELETON FROM PAKISTAN
—SANDERS, William, University of Michigan Museum of Paleontology, Ann Arbor, MI, USA; GRAF, John, University of Michigan Museum of Paleontology, Ann Arbor, MI, USA; ZALMOUT, Iyad, University of Michigan Museum of Paleontology, Ann Arbor, MI, USA; UL-HAQ, Munir, Geological Survey of Pakistan, Quetta, Pakistan; GINGERICH, Philip, University of Michigan Museum of Paleontology, Ann Arbor, MI, USA
A Geological Survey of Pakistan-University of Michigan team working on the western side of the Sulaiman Range in Balochistan, Pakistan has recovered a diverse marine mammal assemblage, including an articulated protocetid whale skeleton (GSP-UM 3551), from middle Eocene (mid-Lutetian) sediments. GSP-UM 3551 is valuable for understanding the transformation of terrestrial to aquatic lifeways in cetaceans because it is the most complete protocetid skeleton known, with all elements of the head and body represented, including the tail and fore- and hind-legs and feet. We detail the technical procedures of field recovery, preparation, and replication used to comprehensively reconstruct the skeleton of this individual. During excavation, bone was consolidated with PVAc, and the specimen was removed in blocks in plaster jackets. Elements were initially prepared within these blocks using airscribes, and molded in articulation. Molds were made of layered silicone rubber, to capture maximum detail, and done in multiple pieces to protect the integrity of original bone. Casts of the blocks were assembled and elements numbered to ensure correct association of bones throughout the process. Elements were then manually prepared out of blocks, and remolded. Next, casts of individual bones were used to restore broken segments and cut apart and reset to correct for plastic distortion and step fracturing. An internal latticework was constructed to rebuild the anterior dentaries, in close alignment with the cranium, permitting precise occlusion of the teeth. Paste epoxy was used for reconstruction, because it is easy to sculpt and retains its shape over time. Reconstructed elements were then remolded and hollow cast in laminar polyester mixed with talc and lined with fiberglass, for dimensional accuracy, stability, and strength. Heating cast copies and bending them into serial alignment with unaffected ribs, directly on the mount, removed rib deformation. The finished mount of GSP-UM 3551 is morphologically accurate, lightweight and internally supported, facilitating placement in dynamic exhibit postures and visual assessment of its amphibious locomotor abilities.
AN EXPLANATION OF THE CHALLENGES AND TECHNIQUES FOR THE EXTRACTION AND TRANSFER OF LARGE WALL PLAQUES
—CRAWFORD, Brett, Research Casting International, Trenton, ON, Canada; FAIR, Matt, Research Casting International, Trenton, ON, Canada; KRUDWIG, Kevin, Research Casting International, Trenton, ON, Canada
Many museums are faced with the inherent problem of re-furbishing their exhibit halls in order to present their visitors something new and exciting. There appears to be a current trend where many museums are finding themselves with exhibits that are well outdated, going back 60 or 70 years or even further. These exhibits were often created with a “last forever” approach in which they were constructed and installed in a more permanent manner. Though many of the smaller exhibits have been dealt with in house, museums are finding that they require a little more assistance with the larger exhibits, especially the large and weighty wall mounts or plaques. Most of these wall plaques are original composites of fossil discovered in situ and sculpted parts made of plaster. The entire plaque is often surrounded and reinforced by massive amounts of diamond lathe, hard wood, steel and especially plaster. A lot of these plaques are also in need of repair due to many factors. Gravity pulling on the tremendous weight of the materials and the effects of prolonged climate changes have created cracks, crumbling and unnecessary stresses on priceless fossils. Even though the plaques may measure 25 feet long and weigh thousands of pounds, it is still possible to extract the plaques from the wall as one unit. This is done by creating a specialized steel frame around the plaque which supports the weight of the plaque in an even manner and allows the plaque to be wheeled away to a new location or destination. This method has been used on numerous occasions. Whether the plaques needed to travel a lengthy distance within the museum or simply as a cosmetic repair within the exhibit hall, they have been removed and transferred all with the successful preservation of the specimen.
THE FLIGHT OF THE MICRORAPTOR
—BURNHAM, David, University of Kansas Natural History Museum and BRC, Lawrence, KS, USA; MIAO, Desui, University of Kansas Natural History Museum and BRC, Lawrence, KS, USA; MARTIN, Larry, University of Kansas Natural History Museum and BRC, Lawrence, KS, USA; ALEXANDER, David, University of Kansas, Lawrence, KS, USA
Discovery of a small, four-winged fossil from China—Microraptor, has led to a debate concerning its posture. If truly a dinosaurian as described, it would be a biped; however, the initial description indicated a sprawling posture to accommodate the hindlimb wings. In order to test the posture and offer comment concerning the possible life habits of Microraptor, a life-size model was made from an actual specimen. The process began with transfer preparation that allowed the fossil specimen to be cast on both sides. These casts were used to reconstruct a skeleton using original morphology and bone details such as articular surfaces. More importantly, the fossil preserved enough evidence to examine the range of motion needed to determine its posture. The reconstructed skeleton was used as a template to build a life model. Feather pattern was based on the nearly completely preserved wing feathers of the holotype, Microraptor gui. Airfoils of the wings were generated from modern avian wing and feather shapes. Afterwards the model was modified so it could be flown. Improvements were made only if they were scientifically justified. For example, the sprawling version improved significantly with proper airfoil alignment of the hindlimb wings and the addition of a delta wing tail. This resulted in more stable and repeatable glides with the longest flight covering nearly 25 meters. This successful gliding experiment strongly suggests the sprawling posture is accurate and conforms to the skeletal morphology of Microraptor.
A NEW “STREAMLINED CRADLE MAKING OPERATION” FOR MAXIMUM PROTECTION OF FOSSILS WHILE ALLOWING FOR EASY ACCESS FOR RESEARCH NEEDS
—NELSEN, Thomas, Utah Field House of Natural History State Park Museum, Vernal, UT, USA; MADSEN, Scott, Utah Geological Survey, Salt Lake City, UT, USA; GRAY, Dale, Utah Friends of Paleontology / Utah Field House of Natural History State Park Museum, Vernal, UT, USA
Dinosaur National Monument is currently undergoing many changes due to the closure of the Quarry Visitor Center. Due to these changes, many of the collections that were housed at the quarry visitor center had to be relocated to alternate storage facilities (housing garages and a semi trailer) located in the park. This meant that some very important and extremely fragile fossils needed to be transported about a half mile down hill from the qvc to the housing / maintenance area by way of fork-lifts and trucks. To accomplish this, we were tasked with developing and providing a safe means by which the fossils could be transported. The three of us collectively researched, designed and built individual bone cradles that provided maximum protection by being strong, light weight, completely concealed and at the same time providing easy access for researchers. Our design and methods incorporated some of the techniques and ideas previously used by the Smithsonian Institute. Due to time and budget constraints we had to design a more quick, efficient and cost effective method in comparison to some of the other designs that we had researched. The result was an excellent “streamlined” design that utilized less material, stronger material, less man hours and produced a lighter weight cradle. This was also a very cost effective operation that solved our budget concerns. The cradles are designed to be a “clam shell” housing that can be opened from either side. This allows for the specimen to be studied while maintaining a molded, bed-like support structure for the specimen to set in. Our design incorporates the use of sand tables for molding the cradle to the specific fossils, FGR 95 plaster, double bias fiber glass cloth, 1/16” ethifoam and a host of low cost supporting materials and tools. The end result was approximately 20, light weight, protective bone cradles that made the move much easier and safer to maintain the integrity of the fossils during the move.
TINY TEETH: CRETACEOUS MAMMAL TEETH MOLDED AND CAST WITH STORAGE IN MIND
—MASON, Jane, Florida Museum of Natural History, Gainesville, FL, USA
The fossil teeth from Cretaceous mammals are small, fragile, and rare. Molding and casting them in multiple copies ensures safe study by the wider paleontological community and permits a deeper understanding of these uncommon animals. When thirty teeth on loan from the Geological Survey of India were presented for reproduction and collection storage containment, a system had to be devised that allowed continued safe handling and a means for organizing these casts. Using traditional mold design and materials presented problems when the small size and fragility of these teeth were considered. Casting technique, as well as future archival storage, were studied in this light. Preparation of a tooth required using colored carbowax to plug all holes and gaps to ensure safety of the tooth while in a vacuum chamber and colored for easy removal later. The teeth were left on the original mounting pins that acted as handles through the whole procedure. Often less than a millimeter long after preparation, a silicone glove mold was painted on a tooth embedded in warm clay using a microscope and compressed air. The specimen number was inscribed backwards on the collar of the mold close to the tooth. These molds were comprised of several thin layers, and cusps were reinforced with nylon mesh. A thin mold was necessary to allow flexibility and the complete inversion of the mold during demolding and casting to reduce stress on the fragile structure. Differential coloring of the area in the mold where the tooth sits, or the first detail coat, permitted easier casting. The uniform size and shape of the casts was determined by using a hole-punch that exactly fits the internal diameter of a standard collections storage vial to make the mold’s outside form. This tool also makes perfect-fit spacers of ethafoam so that multiple casts of the same tooth can be stacked and stored in the same vial for shipping and or collection purposes. Using these techniques, I was able to process four copies of each tooth while keeping track of the progress of the project. Once all the teeth had been molded and cast, the collection storage format was already accomplished.
LEARNING THE BASICS: A LOOK AT AN ADAPTABLE LAB BASED FOSSIL PREPARATION TEACHING EXPERIENCE
—BROWN, Matthew, Petrified Forest National Park, Petrified Forest, AZ, USA; PARKER, William, Petrified Forest National Park, Petrified Forest, AZ, USA; SUMIDA, Stuart, California State University, San Bernardino, CA, USA
In the absence of a widely accepted professional fossil preparation training program in North America, paleontology departments rely on a variety of informal or less formal methods of staffing laboratories. Many new employees come from volunteer or amateur communities, while others are recent graduates with little or no experience at the work bench. In order to partially address this experience gap, Petrified Forest National Park recently partnered with California State University, San Bernardino, to provide an internship for students with an interest in paleontology to receive basic training in preparation methods. One student spends ten weeks (one quarter) in the Petrified Forest preparation lab and is provided with an extensive list of required reading from the preparation and conservation literature in addition to hands on experience and guidance preparing Triassic archosaurs. These specimens represent a wide variety of preservation and requiring several different methods of chemical and mechanical preparation. The students also receive experience in field work, collections work, and molding and casting. The candidates are evaluated on technical ability, and are tested on knowledge of methods, anatomy, and materials. Experience with three students has shown positive results for the candidate, as well as the park paleontology program. Additionally, this process has provided insight into forming curricular and training models for longer term professional programs, and volunteer or new employee training. The program could possibly be expanded and developed in conjunction with an existing university graduate or undergraduate curriculum, or a large institution could develop a model for a regional training facility.
HEALTH AND SAFETY IN THE PREP LAB: A STEP-BY-STEP GUIDE TO INSTALLING AN EFFICIENT AND COST EFFECTIVE DUST COLLECTING AND VENTILATION SYSTEM
—FINLAYSON, Heather, Utah Field House of Natural History State Park Museum, Vernal, UT, USA; SROKA, Steven, Utah Field House of Natural History State Park Museum, Vernal, UT, USA; NELSEN, Thomas, Utah Field House of Natural History State Park Museum, Vernal, UT, USA
After hearing some presentations regarding the importance of proper ventilation at the First Annual Fossil Preparation and Collections Symposium given at Petrified Forest National Park in April of 2008, our museum decided to take a serious look at the dust collecting system we currently use in our own lab. After hiring a new intern to do fossil preparation, the activity in our lab increased substantially along with an abundance of fine dust accumulating on work surfaces and lab equipment. It became obvious that our current system was simply not sufficient enough to vent the fine dust particles suspended in the air out of the room, not to mention the inherent health and safety issues that arise from inhaling rock dust, fumes, and other particulates. After communicating with other institutions about their prep lab dust collecting and ventilation systems, we came to the realization that no formal standards have ever been developed for what would be considered an optimal system that takes into account the size of the room, the amount of airflow needed for sufficient dust removal, and the appropriate type and size of unit needed for the very specialized work that is done in a preparation lab. Our goal is to share the step-by-step process we used for the design and installation of our new system. We hope that the results of our project can serve as a template for other institutions that need a simple, affordable system that is both efficient and addresses the health and safety of their staff.
Poster Presentations
ENSURING SUCCESS FOR ALL IN EXHIBITIONS AND INFORMAL SCIENCE PROGRAMS
—DECK, Linda, Bradbury Science Museum, Los Alamos, NM, USA
Historically, exhibitions and informal science programs filled out an institution’s expected portfolio of public offerings, guided often by an individual’s work and vision. There was trust that this vision was appropriate and compelling, accurate and up-to-date, and would contribute to the institution’s positive reputation. The institution’s (or funder’s) desire to be known for scholarly, engaging, and original public offerings still exists, but now also regularly includes a business model mentality requiring a demonstrably valuable result. These two motives can be combined, resulting in a successful project from all viewpoints. A robust approach to planning a successful exhibition or informal science education program begins with a clear idea of what the goals are for the project that directly relate to the mission of your institution or program; who the user is and their underlying capacities and needs; who the stakeholders are who contribute money, space, reputation, and/or resources and demand positive return on investment; and who are partners in the project that have their own agendas to meet and what these are. This leads to the ultimate outcomes; meaningful change in the user of the project relating back to their compelling needs which also has meaning for the stakeholders. Following this logic model enables the project planners to chart a course directed toward achieving measurable success for all invested. The plan should detail inputs of resources and the activities that will produce the project; activities lead to outputs that can be measured and show accomplishment and success while the project is still in progress. The ultimate measures of success are changes to the knowledge, attitudes, or behaviors of the users. Shifting the focus to the user, not the project, ensures the resources spent will add up to a meaningful investment. Examples of using this method for exhibitions, informal science programs, and to guide the work of entire informal science education institutions will be illustrated. Methods and examples of user needs and capabilities assessments, output and outcomes tracking, and producing and using this planning method will be shown.
PLASTER
—FITZGERALD, Vicki, Yale Peabody Museum of Natural History, New Haven, CT, USA
Plaster seems to be a simple substance that can be created by dumping the powder into water, mixing and applying the “batter”. The setting of plaster is, however, an exothermic chemical reaction. There are many problems that can interfere with the chemical reaction that causes plaster to set, especially so in the field. These can cause difficulties such as a watery mix that never sets, plaster the consistency of talcum powder, or cracking caused by moving partially cured plaster. In every stage of plaster use, whether in the field or the lab, there are key considerations such as water and air temperature, ratio of plaster to water, mixing speed, technique, and application methods. The final use for the plaster needs to be assessed in order to choose the right kind of plaster: for example is the plaster needed for a mother mold, a mold, a cast, a field jacket, a brace, or a long-term storage jacket? Does the plaster need to set quickly as in field conditions or does the technician need the maximum amount of time to manipulate the plaster before setting? With practice this medium is a great help with fossil collecting, reproduction and storage. There are many ways of handling plaster, this paper will present some of the methods in use at the Yale Peabody Museum that may be adapted for particular needs.
THE METHODS AND DATA COLLECTION IN FOSSIL BONE PREPARATION PROCESS: TURNING SCRAP MATERIAL INTO PREMIUM SCIENTIFIC, EDUCATIONAL, AND EXHIBIT RESOURCES
—POTAPOVA, Olga, The Mammoth Site of Hot Springs, Inc., Hot Springs, SD, USA
The proposed strategy of data collection of the fossils going through the preparation process is suggested based on the performed preparation of the Woolly mammoth molars collected along with other bones in the Long Hollow Creek two miles northwest of Sisseton, Roberts County, SD. The very few fossil bones and fragments were remnants of the second complete mammoth skeleton found east of Missouri River in SD, most of which were in too poor of condition to save and preserve. These bones have been owned and stored by the Heritage Museum of the Coteau des Prairies and Sisseton School District 54-2, Sisseton, SD since their discovery In early 1940’s. It is planned for the restored materials to be exhibited in the Museum; also displayed will be the “behind the scenes” preparation records, conservation methods used, and photo-documentation. The Mammoth Site was contacted by both organizations regarding the restoration and the specimen exhibits. During the restoration and conservation of the fossils the following procedures were developed to capture the data and preserve the scientific integrity of the specimens; photo documentation of every major step in reconstruction, daily records of the preparation activities and material use in record forms, and image-mapping of the reconstructed areas of each prepared specimens. Based on completed reconstructions, identification of teeth generation, analyses of the wear patterns, approximate individual age of the mammoth, recommendations on long-term storage or exhibit, and specimen samplings for AMS and other analyses were provided. The paper materials, supplemented by images, will provide the in-depth conservation methods and data collection of the prepared material.
THE USE OF URETHANE RESIN AS A NOVEL APPROACH TO THE STABILIZATION OF A LARGE NEARLY INTACT LAND TORTOISE FROM THE LATE PLIOCENE OF NEW MEXICO
—NORTON, J., New Mexico Museum of Natural History, Albuquerque, NM, USA; RINEHART, Larry, New Mexico Museum of Natural History, Albuquerque, NM, USA; MORGAN, Gary, New Mexico Museum of Natural History, Albuquerque, NM, USA
After encountering great difficulties in maintaining stability in a fragile 1 m tortoise fossil using standard techniques, it was decided that an entirely new approach should be considered so that this nearly complete fossil shell could be studied and displayed to greatest advantage. The specimen (Hesperotestudo sp.) was found partially exposed in Gila Group sediments in Hidalgo County, in the southwestern corner of New Mexico .The fossil shell was found packed solidly with matrix and was transported in a classic plaster jacket. Conventional wisdom would have dictated leaving the matrix in the specimen to stabilize it. The presence, however, of numerous girdle and limb elements along with important small vertebrate fossils necessitated its removal. As the matrix and multiple skeletal remnants were removed, it became apparent that the plastron (now in superior position) was too fragile to be supported by the bridges of the shell. Cyanoacrylate products did not adequately penetrate the entire thickness of shell structures and wooden supports were required as matrix was removed. After preparation of the inner surfaces a clear urethane resin (Crystal Clear 202tm) was applied in multiple coats to achieve an eventual thickness of 3 to 5 mm. Metal struts were installed for further support once the interior preparation was completed. The resin (ordinarily used as a casting compound) cures as a very hard, clear plastic and provides support while still allowing excellent views of underlying details. A test performed on a carapace fragment showed that the resin penetrated the fossil much more deeply than cyanoacrylate penetrant, thus providing excellent stabilization. We have no data on which to gauge the life expectancy of this resin but are confident that without it this large specimen could not be prepared and displayed as effectively.
THE TRIALS AND TRIBULATIONS OF EXCAVATION: TECHNIQUES FOR REMOVING LARGE, HEAVY FIELD JACKETS
—SROKA, Steven, Utah Field House of Natural History State Park Museum, Vernal, UT, USA; FINLAYSON, Heather, Utah Field House of Natural History State Park Museum, Vernal, UT, USA
Each paleontological excavation has its own unique challenges and it takes innovation, creativity and patience, to come up with techniques that work well to overcome obstacles encountered while attempting to remove fossil bone. One such quarry is the Utah Field House’s sauropod site located on a small patch of BLM land near Dinosaur National Monument. The fossils are coming out of the Jurassic aged Brushy Basin Member of the Morrison Formation. There are several factors that make this site challenging. The bone is highly fractured and incomplete, many of the bones overlap, and new bone is often exposed while trenching around a block. In addition, extremely hard channel sandstones lie above and within the bone bed, making it very tiring and time consuming to work in. Furthermore, the bone is coming out of the side of a steep hill, and is trending back into the hill, which calls for frequent removal of overburden. The problem of an oversized field jacket arose when trying to deal with three smaller jackets that lay adjacent to each other. As we trenched around these jackets, we encountered bone that appeared to be overlapping with the adjacent block. The three jackets consisted of parts of cervical vertebrae that were partially articulated. Rather than continuing to trench between the jackets and risk destroying bone in the areas of overlap, we incorporated all of them into one large block. We used electric hammer drills and chisels operated by a small generator to remove the hard sandstone around the block. Longer drill bits were used to drill tunnels through the pedestal and plaster bandages were threaded through the tunnels to prevent rock from falling out of the bottom of the jacket. Two-by-fours were used to reinforce the jacket and holes were drilled around the base of the pedestal, creating a fracture plane that helped the jacket break free when we rolled it. A backhoe was used to build an earthen ramp for easier access up the hill to the quarry. Once the jacket was rolled, the backhoe lifted the jacket up, transported it down the ramp and loaded it onto a trailer.
STABILIZATION AND REPAIR OF LARGE CRACKS IN SIDERITE ROCK
—HANKS, H., Marmarth Research Foundation, Marmarth, ND, USA; HAIRE, Scott, University of Minnesota, Dept of Water Resource Science, St. Paul, MN, USA
An articulated hadrosaur with skin impression preserved over large portions of the body was collected in 2006. The skin was preserved as a siderite mold. Large cracks in the siderite were evident prior to the excavation but were not fully treated because of the possibility of damaging the fragile skin. These cracks, some as large as 10 millimeters, were treated in the laboratory after the blocks had been prepared down to near the level of the skin. Since the blocks contains both prepared and unprepared skin impressions as well as bone underlying the surface of the matrix a technique was developed to stabilize both edges of the fracture zones in stages using various viscosities of cyanoacrylate glue. Penetrant stabilizer was applied first to seal the cracks. Increasing viscosities of glue were then applied until the cracks were completely filled resulting in complete stabilization of the cracks. This technique has also been used on vertebrate trackways from the Late Paleocene Bullion Creek Formation prior to their removal from the field. Application of increasing viscosities of cyanoacrylate glues is a successful method for gluing solid rock.
CHALLENGES OF A NATIONAL PARK PALEONTOLOGICAL QUARRY: THE BIG PIG DIG
—STARCK, Ellen, South Dakota School of Mines & Technology, Rapid City, SD, USA; WEILER, Matthew, University of North Dakota, Grand Forks, ND, USA; HOFFNAGLE, Eric, South Dakota School of Mines & Technology, Rapid City, SD, USA; OLINGER, Danielle, South Dakota School of Mines & Technology, Rapid City, SD, USA; DOPHEIDE, Amanda, South Dakota School of Mines & Technology, Rapid City, SD, USA
The Big Pig Dig, located in Badlands National Park, South Dakota, is a unique site, both scientifically and in public allure. The Pig Dig is distinguished by its proliferation and concentration of Orellan fossils, yet the site also allows unprecedented ease of public access to the daily workings of a scientific excavation. Since the Pig Dig is a seasonal operation, multifaceted challenges result from an array of factors. A rotating crew offers an exceptional opportunity for students to gain experience in all aspects of quarry mapping and excavation. Nevertheless, the lack of consistency in education among staff as well as an absence of cumulative experience from year to year can be a hindrance. In response, every season must begin with intensive training to keep information current regarding paleofaunal lists, data accuracy, and methods of collection and documentation. Internal operations of the excavation have been held consistent and critical errors have been minimized by initiating a standard operating protocol in 1998. Visitors impart a different set of challenges in that they expect to be informed and engaged while interacting with the excavators. Ensuing enthusiasm often results in visitors overstepping established park guidelines via unauthorized fossil collection, degradation to quarry walls, damaging exposed fossils, and possible personal injury. Visitors are updated by means of wayside exhibits, onsite interpretive rangers, and park bulletins alerting them to all aspects of resource management and visitor safety. Severe weather affects Total Station performance, and extreme conditions pose great risks to unconditioned visitors. As a result, a network of shelters has been erected, and first aid provisions and emergency communications are readily accessible. The remoteness of the Pig Dig presents a security threat, and easy road access to the site offers substantial temptation for after-hours violation. To deter site breaches, increased vigilance has been implemented through the support of park law enforcement. Furthermore, the site is secured daily during excavation, and the quarry is refilled and closed at the end of each season.
REVERSIBLE FILLER: A FRESH LOOK AT BUTVAR-76
—HAUGRUD, Shawn, East Tennessee Museum of Natural History, Gray, TN, USA; COMPTON, Brian, East Tennessee Museum of Natural History, Gray, TN, USA
B-76 (polyvinyl butyral) has long been used in fossil preparation as an adhesive. By changing the ratio of solvent to solution and using a variety of new techniques, B-76 can be used to create filler that is both reversible and archival and therefore preferable to other more traditional fillers. Due to its several desirable properties, it is ideal for making specimens ready for museum display without detracting from their research value. B-76 filler can be reversed with very little trouble, which makes it a better candidate for museum prep than more commonly used fillers that are permanent. Serious damage occurs if permanent fillers must be removed, a process that often involves grinding tools. B-76 filler can be dissolved with the application of acetone. The process can be accelerated by removing the bulk of the filler with cutting tools. B-76 filler is very strong but can easily be removed with a razor, and the remnants can then be dissolved away and cleaned off. B-76 in its purest form is translucent. From a researcher’s standpoint this can be desirable as traditional fillers obscure the actual fossil and make it unclear what is real and what is replicated. Yet it still holds the various elements together in a pleasing way suitable for display. If the first priority for the specimen is display and the preparator so desires, various coloring substances can be mixed into the filler while it is being made. B-76 can also be used to coat the breaks/contacts and then traditional filler can be used to fabricate the missing elements with the B-76 acting as a buffer that can later be removed. B-76 filler is incredibly strong. Even when stretched into thin sheets its performance when stressed is remarkable. Unlike other fillers it is not brittle, it holds a rigid form but should not crack under extreme stress. In fact it should bend somewhat before any tearing occurs. In this way it could be compared to metal where other fillers are more like cement. Due to this strength it can be used to rebuild extremely thin or delicate structures, such as palates more accurately.
REMOVING FOSSIL RIBS: THE THREAD TECHNIQUE
—DAVIDSON, Amy, American Museum of Natural History, New York, NY, USA
Preparators often face the problem of extracting high priority pieces (e.g., cranial elements) from beneath ribs in jumbled vertebrate fossil skeletons. The thread technique was recently developed when faced with this situation in preparing two dinosaurs; one from Ghost Ranch (New Mexico) and one from the Gobi Desert of Mongolia. Both blocks contain skeletons preserved as dense assemblages of disarticulated bones that must be separated and prepared as individual elements. Especially problematic are areas where multiple, fragile, fractured ribs are interwoven and overlying skull elements. In order to untangle and lift each rib, a piece of sewing thread is first adhered to the surface with a thick, temporary coating of Acryloid/Paraloid B72 in acetone. The thread and thick coating span the fractures and gaps to hold them together but remain flexible. With this system the overlying end of one rib can be folded back to pull out an underlying rib. The rib is then lifted on the thread like a beaded necklace preserving the order of the segments. The thread technique allows the ribs to be set aside indefinitely while higher priority elements are removed and prepared. The rib fragments are later removed from the thread one by one, the coating cleaned with a needle or acetone and the fragments reassembled with a thick (50%) solution of Acryloid/Paraloid B72 in acetone.
QUANTIFYING THE BENEFITS OF A HEAVY LIQUID (SODIUM POLYTUNGSTATE) SEPARATION TECHNIQUE ON MICROVERTEBRATE FOSSIL RECOVERY
— MITCHELL, Jonathan, Appalachian State University, Boone, NC, USA; HECKERT, Andrew, Appalachian State University, Boone, NC, USA; SCHNEIDER, Vince, North Carolina Museum of Natural Sciences, Raleigh, NC, USA
The extraction of microvertebrate fossils from similar sized clasts (via picking) is by far the most time consuming and daunting aspect of microvertebrate study. The thought of picking many kg of matrix one grain at a time is rather discouraging, but the process can be expedited. The use of a heavy liquid to facilitate the sorting process is not new, nor is the use of the safe (if expensive) salt known as sodium polytungstate (SPT). However, we have attempted to identify the ideal procedures and quantify the benefits of SPT separation, and we made several innovations. Thus we have: 1. Approximated the densities of various fossil types (bone, teeth, fish scales, etc.) 2. Identified the ideal working density (2.73-2.78g/ml) to minimize sand in the sink, and also minimize the chances of SPT evaporating to a solid. 3. Timed the rates of descent through the SPT of these same fossil types (0.5-13mm/sec). 4. Quantified the time saved by using SPT over the more traditional picking (474 hours are saved per kilo at an assumed picking rate of 1000 grains per hour). 5. Found that covering the working surfaces with plastic wrap greatly reduces the loss of the very valuable SPT. 6. Discovered that a nylon mesh net, weighted down with sealed plastic vials containing steel shot, greatly facilitates recovery of “heavies” (fossils and heavy sand). Our methodology was fairly straight forward. Picking through a site (a clay rich deposit from the Newark Supergroup), we counted the occurrence of fossils versus that of concentrate (sand), and then weighed known amounts of fossils and sand to find both a mass percentage (1%) and a count percentage (1%) of fossils. We then performed simple density tests on various fossil types to determine the ideal density to work with the SPT. We then processed in excess of 12 kg in ~24 working hours. Picking through the heavies, we again counted the occurrence of fossils versus sand (20% fossil), weighed them (17% fossil), and compared those results to the unfiltered data. We also examined the “float,” in an attempt to see how many fossils were lost, and we report that nearly none were (<0.01% by count).