|Rocky Mountain Section - 61st Annual Meeting (11-13 May 2009)|
|Paper No. 11-16|
|Presentation Time: 8:00 AM-5:00 PM|
SEDIMENTARY PETROLOGY AND RESERVOIR CHARACTER OF A POST-EXTINCTION CARBONATE PLATFORM: THE EARLY TRIASSIC (SMITHIAN) SINBAD LIMESTONE MEMBER OF THE MOENKOPI FORMATION, UTAH
RITTER, Scott M., Geological Sciences, Brigham Young University, S-389 ESC, Provo, UT 84602, firstname.lastname@example.org and OSBORN, Caleb, Chevron, USA, Midland, TX 79707|
The Early Triassic (Smithian) Sinbad Limestone Member of the Moenkopi Formaton has produced minor amounts of oil in the Grassy Trail Creek Field near Green River, Utah and is present below much of central Utah, including the recently discovered Covenant Field. Superb outcrops of this thin (15 m), mixed carbonate-siliciclastic unit in the San Rafael Swell permit detailed analysis of its vertical and lateral reservoir heterogeneity. Vertically, the Sinbad comprises three grain-dominated facies associations: (A) a basal, storm-dominated, well-curculated skeletal-oolitic-automicritic limestone association, (B) a middle storm-dominated, restricted-marine hummocky cross-bedded peloid-siliciclastic association, and (C) a capping peritidal, cross-bedded oolitic-peloidal dolograinstone association. Lateral variation in lithology is most pronounced in the upper part of the lower limestone where storm-dominated beds pinch our over a distance of one kilometer. Otherwise, individiuual beds, microfacies, and hardground surfaces display a high degree of lateral homogeneity and regional persistence. The lack of mud and presence of automicrite in low-diversity grain-dominated packstones are likely the result of deposition under anachronistic conditions reflecting the aftermath of the end-Permian mass extinction. Diagenesis is strongly tied to microfacies in this mud-lean unit and is represented by fibrous marine calcite cement, micritization, compaction, dissolution and cementation of aragonitic grains, meteoric cement, and dolomitization. Hydrocarbon-lined vugs and interparticle pores characterize the skeletal limestones.
Rocky Mountain Section - 61st Annual Meeting (11-13 May 2009)
General Information for this Meeting
|Session No. 11--Booth# 17|
General Discipline Posters
Utah Valley University: Library 4th Floor
8:00 AM-5:00 PM, Tuesday, 12 May 2009
Geological Society of America Abstracts with Programs, Vol. 41, No. 6, p. 37
© Copyright 2009 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.