GSA Annual Meeting in Phoenix, Arizona, USA - 2019

Paper No. 271-28
Presentation Time: 9:00 AM-6:30 PM


RUSH, Madison T.1, GHEZZO, Elena1, WELDON, Ray2 and HOPKINS, Samantha S.B.3, (1)Department of Earth Sciences, University of Oregon, 1585 E 13th Ave, Eugene, OR 97403, (2)Department of Geological Sciences, University of Oregon, Eugene, OR 97403, (3)Clark Honors College and Department of Earth Sciences, University of Oregon, Eugene, OR 97403

One of the major difficulties in placing vertebrate fossils in geologic context is the fact that the majority of terrestrial vertebrate fossils are found in float, disassociated from the precise geologic context in which they were originally preserved. However, high-density field data collection can help solve the problem of placing disassociated fossils in their proper geologic context. Field paleontology courses at the University of Oregon have prospected the Crooked River Basin of Central Oregon over several of the last 10 years. In the field, students are required to record data from their findings, including the GPS coordinates of fossils they discovered during the surveys. To promote the development of practical skills, students were also required to draw their prospecting paths on aerial photos, including the exact points of each specimen they discovered. These data offer abundant, high resolution information about the geographic distribution of fossils, both where they are and are not preserved. However, the data present some challenges to geographic analysis. The raster data presented in the student maps originate from different groups of students, working on maps with different resolutions, at varying times, with varying precision. The data, in particular the GPS points collected in the field, contain a varying degree of uncertainty; therefore retracing and comparison of the specimen coordinates from the raster data was needed to verify whether the GPS from the physical maps or the GPS derived from Google Earth was more consistent. Through georeferencing of the physical maps, we vectorialized the information they contained using standard QGIS tools. Then, we organized the resulting datasets to create a single map of organized data. This organization allowed us to see concentrations of fossils within a specific locality. We present here the resulting concentrated map of the field and the filtered maps that were obtained, taking into consideration the stratigraphy and slope of the exposed outcrops. Our maps allow future field trips to be more targeted in their surveys, giving the professors and students involved a clearer understanding of where fossils may be discovered as well as a precise view of how the topography of the area can affect a paleontological survey.