The 82nd Annual Meeting of the American Association of Physical Anthropologists (2013)


Ground-truthing a neural-network based predictive model for locating productive fossil localities in the Eocene of Wyoming

ROBERT L. ANEMONE1, CHARLES W. EMERSON2, BRETT NACHMAN3, GLENN C. CONROY4 and RON WATKINS5.

1Anthropology, Western Michigan University, 2Geography, Western Michigan University, 3Anthropology, University of Texas, 4Anthropology, Washington University in St Louis, 5Applied Geology, Curtin University

Thursday 8:00-8:15, Ballroom C Add to calendar

Remote sensing and other tools and methods from the geographic information sciences have the potential to revolutionize how paleoanthropological fieldwork is performed. We trained a neural network to analyze remotely sensed imagery and multiple GIS data and analytical layers in order to recognize different land cover classes, including productive localities, in Eocene deposits of the Great Divide Basin of southwestern Wyoming . Post hoc testing of the model indicated that the model was able to recognize the spectral signatures of productive localities and other land cover classes with a high degree of accuracy (84% correctly classified). Our predictive model was constrained by geology (limited to outcrops mapped as Wasatch formation), by topography (minimum required slope was 5%), and was limited to pixels which resembled known localities at the 98% probability level. Ground truthing of the model took place during the summer 2012 field season.

The first area we surveyed yielded characteristic Eocene fossils (turtle, fish, crocodile, gastropod, bivalve) in deposits whose lithology (paper shales and stromatolites) suggested a lacustrine origin. We confirmed that these deposits have been mistakenly mapped as Wasatch formation and should be attributed to the Green River formation. In the second area, the lithology was clearly fluvial and the rocks were typical of the Wasatch formation (sandstones and mudstones). The area indicated by our model as having a high priority of being fossilferous was in fact a large outcrop of heavily eroded sandstone that yielded typical Eocene terrestrial mammals, including Hyracotherium and Hyopsodus.

This fieldwork was funded by several grants from Western Michigan University to RLA and CWE. Fieldwork was facilitated by the Wyoming State Office of the Bureau of Land Management (Paleontological Resources Use Permit 287-WY-PA95).

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