From Slope to Basin – A Core Workshop Focusing on the Variety of Gravity Flow Deposits throughout the Permian Basins
American Association of Petroleum Geologists
Sunday, 19 July 2020, 7:30 a.m.–5:00 p.m. | Austin, Texas
Whole core from both the Delaware and Midland Basins will be examined to understand the changes in slope deposits from both confined and unconfined settings. We will examine a variety of gravity flow deposits within the basins and the processes they were generated from. The end goal of this course will be to understand how these deposits impact reservoir quality in the basins.
The selection of cores from the Delaware will contrast rock deposits in confined slope environment and unconfined toe-of-slope to basin environments. We will examine several cores that provide examples of both carbonate and siliciclastic deposits of the Wolfcamp A (Leonardian), 2nd and 3rd Bone Spring, and Avalon plays. Interpreted sedimentary environments range from channelized debris flows, grainy confined slope fans, to unconfined basin floor off-axis to fringe environments. When placed within a larger depositional framework, these cores provide an anchor point for explaining the proximal to distal facies transition within the Delaware Basin’s Permian mixed-system.
Core in the Midland basin will focus on the Spraberry Formation. These cores will illustrate the main three facies types: turbidites, transitional flow deposits (TFD), and a parallel laminated siltstone facies. The main point of discussion will center around the origin of the enigmatic laminated facies and its relation to the turbidites and TFDs. Preliminary observations suggest that some laminated intervals can be correlated across a distance of more than 1.3 km, with a high certainty, at a lamina-by lamina scale. This is consistent with the idea of settling of fine-grained sediment from density currents that are not hugging the bottom but spread out along a pycnocline. The fine-scale correlatability of the laminated facies also suggests the potential for robust long-distance correlations in similar setting.
Cores from both the Midland and Delaware Basins may be applied as analogs for strata of different ages and in other deep-water basins with similarly interpreted depositional environments.
- Regional geological introduction of the Permian of the Delaware and Midland Basin
- Industry perspective on core values for unconventional exploration and exploitation
- Shelf to Basin architecture of the Northern Delaware Basin
Delaware Basin Core
- Up-dip confined system on the Leonardian Wolfcamp A. slope in Eddy County, NM
- Basinal mixed carbonate-siliciclastic unconfined deep water fan system of the Wolfcamp A., 2nd and 3rd Bone Spring intervals in Eddy Co., NM and Ward Co., TX.
- Gravity-flow deposits and reservoir quality in Avalon and 3rd Bone Spring sections in the southeastern Delaware Basin, Reeves County, TX.
Midland Basin Core
- Submarine fan depositional architecture: Facies continuity in the lower Permian Spraberry Formation, Jo Mill Field, Borden and Dawson counties, TX.
- Core workshop wrap-up session
Austin, TX - Bureau of Economic Geology
10611 Exploration Way