Multiattribute Analysis to Assist Structural Interpretation: An Example for a Structurally Complex Onshore Oil Field in Eocene Calcareous Conglomerates Veracruz, Mexico

Abstract

Abstract

Multiattribute analysis is a powerful methodology that accelerates structural interpretation on highly deformed terrenes. This case study focuses on an onshore oil field in the eastern margin of the tectonic buried front of Sierra de Zongolica, in the Veracruz Basin, southwestern Mexico. The field produces heavy oil from vertically independent horizon reservoirs separated by shale impermeable layers, Eocene in age. The principal structure is that of a fold propagation fold. One of the major challenges in the area is the compartmentalization caused by post-orogenic normal faults, some of which fall below seismic resolution that are not identified until the well is tested. The purpose of this study is to delineate the structural framework using a multiattribute-assisted workflow. We use multiattribute analysis of volumetric coherence and curvature extracted over data conditioned through a structural oriented filtering (SOF) to delineate structural patterns that are not evident on the amplitude data. We find that the shape index attribute, which quantifies the deformation morphology of seismic reflectors, can be successfully used to delineate compartments. Some curvature anomalies are fault-related when they are accompanied by low coherence patterns. Other curvature features that do not correlate with domes or ridges can be correlated with fractured zones or relay ramps. Multiattribute analysis coupled with an appropriate tectonic deformation model is a powerful methodology that accelerates identification of structural patterns in complex fractured areas. This methodology can be applied to assist structural interpretation in similar tectonic fronts that had been highly deformed.

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