Effect of Diagenesis on Carbonate Ramp Architecture, Last Chance Canyon, New Mexico

Abstract

Abstract

The Permian Upper San Andres formation in Last Chance Canyon (LCC) represent the outcrop analogue of one of the most extensive siliciclastic/carbonate plays in the Permian Basin. As 2D outcrop, LCC is a popular example of a prograding siliciclastic/carbonate ramp system. This project is field-based and integrates hand samples, thin sections, geological measured sections, gamma ray profiles, drone-based LIDAR and photogrammetry into a comprehensive 3D model of the LCC ramp system. The overarching goal of this research is to delineate the system's internal and external controls and their effect on geological variability and depositional rates to better understand universal process-system relationships in carbonate systems spatially and temporally. This will be achieved by quantifying the 3D variability of facies distribution, depositional geometries and depositional rates within the prograding carbonate clinoforms.

Enhancing the existing 2D outcrop information into a comprehensive 3D model represents a novel approach to the outcrop-based investigation of carbonate systems. With this approach, progradation rates can be quantified as distance over time, as well as sediment volumes deposited in a given time interval. As a consequence of an improved understanding of universal process-form relationships and the effect of internal and external controls on facies distribution, the accuracy of existing carbonate reservoir models can be increased and reservoir properties in these systems can be predicted more accurately.

This study puts focus on the effect and extent of late stage and near surface diagenesis on the siliciclastic and carbonate rocks in LCC as part of the extensive characterization of the system. Diagenesis serves as internal control that affects ramp architecture by influencing factors such as compaction and fracture behavior. Multiple stages of dissolution and cementation were identified that negatively affect pre-existing porosity and permeability in the rocks. During preliminary work on the carbonate system in LCC, field measurements and samples were reconciled with previous sequence stratigraphic interpretations. Ongoing work will focus on the larger scale effects of diagenesis on compaction and fracture behavior, as well as the integration of field observations with drone-based LIDAR and photogrammetry data to model facies distribution and sediment volume progradation in 3D.

AAPG Datapages/Search and Discovery Article #90260 © 2016 AAPG/SEG International Conference & Exhibition, Cancun, Mexico, September 6-9, 2016