Facies Mapping of Panther Tongue outcrops in Spring and Huntington Canyons

Abstract

A comprehensive understanding of reservoir architecture, facies distribution, and lateral variability of geobodies is essential to creating accurate reservoir models. Well and seismic data cannot completely assess these vital factors to reservoir modeling. This study uses two well-exposed delta outcrops of the Panther Tongue in central Utah as analogs for deltaic reservoirs. Utilizing high-resolution UAV (unmanned aircraft vehicle) imagery and virtual outcrop geology software, 24 kilometers of outcrop in Spring and Huntington Canyons are modeled. Five facies exist within these models: prodelta, lower delta front, upper delta front, lag deposit, and distributary channel. These facies are mapped laterally across the outcrops from proximal to distal regions and off-axis of progradation. Facies distributions are used to create paleogeographic maps of the area during deposition in the Late Cretaceous. Additionally, facies mapping and reservoir classification reveal the upper delta front has the best reservoir quality which degrades in the distal direction. In contrast, off-axis outcrops did not experience a change in reservoir quality. Smaller-scale sand bodies within the interpreted facies are also mapped to better understand reservoir architecture. Measurements of sand beds, which include bed thicknesses, pinch-out lengths, and dip angle, are compiled into a large dataset. Highly dipping beds (up to 6 degrees) have shorter pinch-out lengths and are shingling in outcrop. In contrast, beds with lower dips (under 1 degree) are more laterally extensive, amalgamate, and have better reservoir quality. Facies relationships and reservoir architecture impact reservoir quality and fluid flow; a better understanding of both leads to optimized recovery and more informed drilling.

AAPG Datapages/Search and Discovery Article #90374 © 2020 AAPG Rocky Mountain Section Meeting, 2020 Vision: Turn Hindsight to Foresight, Grand Junction, Colorado, September 13-15, 2020 (CANCELLED)