Files containing information on core lithology, mineralogy, and thin section petrography, as well as photos of samples.
The primary objective of this research is to understand how different rock types, mineral and fluid compositions, and fracture surface textures determine the longevity of fracture apertures, so that selection of reservoir rock can be economically optimized to reduce future refracturing. We are performing laboratory tests to study this in a custom apparatus at conditions relevant to EGS, with temperatures up to 250 degrees C (design maximum 300 degrees C). Our approach is to perform a number of long term (up to several months) laboratory experiments using relevant rock samples with different mineralogies to explore fracture sustainability under EGS conditions. We use an apparatus that allows direct application of a normal force on the fracture faces of a single fracture in a sample having a sheared, tensile fracture. We flow brine of a specified composition through the aperture, and simultaneously measure the fracture permeability and closure. We collect the effluent water for chemical and isotopic analysis. We are numerically modeling our tests and comparing experimental and numerical results. This submission includes photomicrographs of pre-test (unreacted) and post-test (reacted) samples from Brady well BCH-03 at various depths, Desert Peak well DP 35-13, and samples of Stripa granite. The photomicrographs are provided using uncrossed and crossed polarized light (xpl). UN is uncrossed nicols, CN and xpl are crossed nicols (crossed polars). The magnification listed is just referring to the objective lens that was used, not the total magnification of the images. With a 5x objective, the bottom dimension of an image is 1.75 mm. With 10x the bottom dimension of an image is 0.875 mm, and with 2x the bottom dimension of an image is 4.375 mm.
Thin sections, sedimentary graphic logs, and XRD results from CFU31-F2 and CFU31-F3 wells. Data collected as part of geologic characterization phase of SECARB project at the Cranfield oilfield in southwest Mississippi. Thin sections for CFU29-12 well also included. Associated Publications: Kordi, M., 2013, Characterization and prediction of reservoir quality in chlorite-coated sandstones: evidence from the Late Cretaceous Lower Tuscaloosa Formation at Cranfield Field, Mississippi, U.S.A., The University of Texas at Austin, Ph.D. dissertation, 193 p.
Thin Section Photomicrographs from 05-06OW at Bell Creek