Complex Reservoir Architecture As Revealed By Broadband Wide Azimuth 3-D Seismic – Implications for Reservoir Risk In the Deepwater Salina del Istmo Basin, Mexico

Abstract

Abstract

Reservoir presence and quality have historically been key exploration risks in the Gulf of Mexico. In the shallow water portions of the Salina del Istmo province, a region with decades of established production, prediction of reservoir quality and lateral distribution remain challenging. As the focus of exploration shifts increasingly to deeper water, a detailed understanding of slope to deep basin sediment transport pathways is crucial for a proper understanding of potential reservoir architecture and quality. De-risking of those elements will enable operators to identify sweet spots of the basin and accelerate the appraisal and development cycle. Expanding the bandwidth of surface seismic data, particularly towards low frequencies, is essential for many exploration and production objectives. Broader band signals, in both land and marine environments have marked benefits for imaging both deeper targets, imaging through absorptive overburden, and delineating fine tectonostratigraphic elements of the subsurface (channels, lithological variations, and faulting).

In the Southern Gulf of Mexico, a major change in sedimentary regime occurred during the Tertiary, when the basin started to receive siliciclastic sediments that were deposited in channels and basin floor fan facies in deepwater settings. Several major pulses of clastic input to the basin can be identified, linked to changes in relative sea level and sediment supply related to uplift of the Chiapas Massif. In several of these cycles, channelized sediment distribution systems can be identified extending up to 350-400 km from the present shoreline. While it is relatively easy to image these stratigraphic elements in the outboard abyssal plain, imaging the architectural elements of turbidite systems becomes increasingly challenging in fold belts and underneath salt.

This paper discusses and presents evidence and examples of imaging fine structural, stratigraphic and tectonic features for potential reservoir identification and characterization. We further demonstrate the benefit of using broadband seismic data to analyze facies distribution and classification for improved reservoir delineation at Eocene, Oligocene and Miocene levels. The area of study covers 44,000 km² of recently acquired broadband wide-azimuth seismic data over the deepwater Salina del Istmo basin and provides a unique opportunity to evaluate depositional systems at both regional and reservoir scales.

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