Sedimentology of the \u22Utica\u22 below Cincinnati

Subsurface geology can be directly observed by means of vertical cores taken at a study site. Investigation of a 300 foot section of core collected from the Ordovician (450 million years old) strata below Cincinnati, OH offers details of depositional environments, sediment composition, fossil distribution, and catastrophic events (e.g. storms, earthquakes, tsunamis, etc.). The core was measured and an accurate lithostratigraphic column was generated to record the lithology and sedimentary structures. This column provides a small-scale diagram revealing sequences and cycles that are present. The core consists of many types of limestone varying from laminated micrite to grainstone. The limestone often transitions into interbedded shale and siltstone. Long segments of core are shale or laminated mudstone. Fossil abundance and burrowing on the stratigraphic column shows that much of the limestone is dominated by bryozoans while the mudstones contain brachiopods. The identification of fauna in the core helps to detect epiboles (layers of unusual abundance of a single fossil species) useful for biostratigraphic correlation and offers indirect evidence of water depth. Important segments of the core were cut lengthwise, one half sanded and polished to allow a mid-scale analysis of the composition and depositional units. The polished section was then digitized with a high resolution scanner. The other side of the slab was processed into thin sections that allow for a high-resolution, quantitative petrographic and paleontological study. The thin sections were also scanned. The digitized material accompanies the lithostratigraphic column and offers an allencompassing report with visuals. These data help with identification and correlation of strata regionally in cores and outcrops. New technology helped to turn North American shale into a practical energy resource. The Utica Shale is a highly productive oil bearing unit. This report will help to establish the continuity of the Utica Shale between Cincinnati, OH and the productive eastern Ohio region, and may help to identify resources further north and west into Indiana.http://opus.ipfw.edu/stu_symp2015/1079/thumbnail.jp