The Sarmiento formation in the Gran Barranca region of Argentina is comprised of eolian, fluvial and volcanic sediment formed between twenty and forty million years ago. Climate change, sea level variation and tectonics driving subsidence were all important factors in the deposition of the Sarmiento Formation and research on the paleoenvironments of the region includes study of eolian and fluvial processes, paleoclimate and the evolution of grasslands. The sediment of the 33.581 million year old Vera section of the Sarmiento Formation is the focus of this study. To better understand the environments of deposition of this section, grain size and magnetic susceptibility were analyzed for over fifty sediment samples. A particle size analyzer was used to provide grain size distributions for each sample, which were then used to look for loess signatures in the sediment. Loess (wind blown sediment) is predominantly composed of fine sand and silt sized particles, and its detection can be evidence of arid, windy climates. Ongoing sedimentary analysis has revealed a predominance of silt sized particles, indicating a loess signature. Magnetic susceptibility analysis is a process that identifies iron-bearing minerals in sediment. The amount of iron present in the Vera sediment can be an indication of chemical weathering in Gran Barranca during the Eocene. Extent of weathering can also indicate past climate conditions. The results of the grain size and magnetic susceptibility analysis for each individual sample will be related to stratigraphic height and age so that a history of climate and environmental change for the Sarmiento Formation can be created.

The Rock Detective Program is a non-profit organization that creates geo-science teaching kits for K-12 teaching professionals.  Students and teachers are able to explore geoscience using a hands-on approach to learning with real geological samples that are fun and educational.  As an intern with the Rock Detective Program, I am creating two geo-mysteries based on Fossil Turtles, specifically Emydid turtles.  Each mystery focuses on a specific age group - primary school and middle school aged children. Mysteries are then used as teaching tools to facilitate teachers and engage children in learning fundamental skills about geo-science not normally learned in a classroom.  Visual analyses, figuring out the approximate age of the specimens, and a final identification and confirmation from experts in the fields of vertebrate paleontology helped to give the mysteries a foundation.  To develop the geomysteries, I researched library and online literature and spoke further with experts.  The resultant mysteries will include information about the physical attributes of the fossil turtle as well as how turtles can provide information about past environment and climate.  I plan to test the mysteries at a local school and use my experience to fine tune the mysteries.  The final versions of the geomysteries will permanently be added to the Rock Detective Program's library.