The following is an abstract of a paper presented at the 2002 annual meeting of the Society of Vertebrate Paleontologists:

DIGITAL MODELING OF A VERTEBRATE TAPHONOMIC QUARRY USING GIS SOFTWARE.

CHADWICK, A. V., Dept of Geology, TURNER, L. E., Dept. of Mathematics and Physical Sciences, Southwestern Adventist University, Keene, TX 76059; SPENCER, L., EHRC, 4754 Carberry Ck. Rd., Jacksonville, OR 97530

We have applied GIS technology to a vertebrate taphonomic quarry site in eastern Wyoming in an effort to achieve an optimal level of data retention. We have accumulated high-resolution GPS data + 1 cm) associated with each bone, then attached this data to digital images of excavated bones, rectifying the images to the GPS data in 3-space. Using this technique in the 3-D module of ESRI’s Arcview, we have reconstructed the quarry site in the computer, giving accurate representation to the absolute positions of excavated materials. The resultant maps can be viewed from any perspective in 3 dimensions.

Using off-the-shelf software, we are able to display the results of successive seasons’ work from each quarry site as a single image. We can view the site from various perspectives, analyze the orientation of long bones, look at the distribution of such things as tendons and teeth and evaluate the spatial relationship between bones suspected of belonging to the same animal. We have also been able to visualize the thickness of the bone layer, the number of bones per unit area, and the vertical profile of the bones in each site. The formidable learning curve for GIS software can be initially sidestepped by focusing only on procedures required for 3-D display.

One of the objectives of taphonomic quarrying is to preserve as much information from the quarry site as possible, not only for the purpose of present investigations, but so that questions can be asked of the data that may not have occurred to investigators at the time of the initial study. Virtual quarry reconstruction requires high standards for data acquisition and retrieval, thereby ensuring the possibility of future queries from different perspectives.

2002 Chadwick, A., L. Turner and L. Spencer. Digital Modeling of a Vertebrate Taphonomic Quarry using GIS Software. Journal of Vertebrate Palontology, 22:43A.

The following is an abstract of a paper presented at the 2000 annual meetings of the Geological Society of America:

HIGH RESOLUTION GPS MAPPING IN A TAPHONOMIC QUARRY

Taphonomic and related sedimentary studies depend upon precise information about field relationships for reconstruction of events in the history of burial and fossilization of organisms. Until recently, this meant overlaying the field relationships with a physical grid and sketching the details in two dimensions. While this technique has been satisfactory for preserving relationships in two dimensions, the procedure left three-dimensional relationships very difficult to reconstruct. We have applied high-resolution GPS mapping and digital photography to a taphonomic quarry, and have satisfactorily reconstructed the field relationships in three dimensions using Arcview GIS software.

Vertebrate fossils (principally dinosaur bones) were exposed in the quarry using standard field techniques. When bones were adequately exposed and pedestaled, they were photographed in their field relationships using a Nikon digital camera. A variable number of points (ranging from one for small fragments or teeth, to many for large bones) were then taken directly from the exposed bone using a Javad GPS having a resolution of 1 cm or less. The points and photographs were transferred to a laptop computer at the end of each day, and processed into individual bone files. These files were converted into three dimensional shape files and the photographs of the bones were overlaid on the three-dimensional GPS data in the computer and displayed in Arcview 3-D module. The resulting three-dimensional reconstruction was highly satisfactory for retaining field relationships and for data analysis. The results give surprising insights into the processes of death and burial and enable predictions to be made about future discoveries. The procedure also enables us to preserve field relationships that might have been lost using older mapping techniques.

2000. Turner, L. E., A. V. Chadwick, and L. Spencer. High Resolution GPS Mapping In A Vertebrate Taphonomic Quarry. Geological Society of America. Abstracts with Program 32:A499.