Reservoir Compartmentalization of Rose Run Sandstone (Upper Cambrian) in South Eastern Ohio
Mihir Pradip Shah
Bowling Green State University, Bowling Green, OH, [email protected]
My study will be focused on the (Upper Cambrian) Rose Run Sandstone. The Rose Run Sandstone was deposited in the Appalachian Basin, and occurs in the subsurface in Ohio. Compartmentalization of Rose Run Sandstone is reflected from studies of previous workers. Analysis of cores and thin section of Rose Run Sandstone by Chuks (2008) in his study of “Subsurface Facies Analysis of Rose Run Sandstone” brings out lateral pinching out of sand units.
The goal of this project will be to evaluate reservoir compartmentalization in the Rose Run Sandstone at field scale and microscopic scale. To understand compartmentalization at field scale, I plan to create a geophysical log model by making isopach, sand isolith and structure contour maps. I will look at large-scale field relationships by using the geophysical log model from around 25 wells located in central Ohio. Based on availability of geophysical logs, wells are selected randomly over an area covering 100 square miles in Holmes County. The logs will include gamma-ray plus neutron-porosity and density. Isopach, sand isolith and structure contour maps might help in bringing out hydrocarbon trapping mechanisms such as up-dip or lateral pinch outs of sandstone, and also in understanding the depositional trend, distribution, geometry of Rose Run Sandstone and individual sand units within Rose Run Sandstone in the study area.
Small-scale compartmentalization will be evaluated by carrying out microfacies analysis from thin sections. The primary goal of microfacies analysis is to be able to understand heterogeneity of the Rose Run Sandstone by investigating their textural, mineralogical and diagenetic history. Cathodoluminescence will be used to identify cement types and also for differentiating common minerals such as quartz, reworked quartz, feldspar and authigenic feldspar based on their color. Thin section study will also involve porosity estimation and mineral composition using point counting methods. A total of around 300 grains per thin section will be counted and percentage composition of the various components making up the thin section will be calculated.
One complete core section of entire thickness of Rose Run Sandstone will be observed for facies analysis. The core section will be calibrated with gamma ray log to correlate lithofacies to subsurface facies. This information can then be extrapolated to other wells where cores are not available.
AAPG Search and Discovery Article #90154©2012 AAPG Eastern Section Meeting, Cleveland, Ohio, 22-26 September 2012