Evaluation of Effective Drainage Height through Integration of Microseismic and Geochemical Depth Profiling of Produced Hydrocarbons

Abstract

This study integrates microseismic hydraulic fracture mapping with geochemical production profiling to understand the interaction between mechanical stratigraphy, fracture geometry, and effective drainage for wells landed in different benches of the STACK play in Oklahoma. Microseismic monitoring was used to map the extents of the hydraulic fracture system contacted during stimulation, while high resolution geochemical analysis or ‘fingerprinting’ was used to assess how different formations in the reservoir were draining. Microseismicity showed that hydraulic fracture growth from an Upper Meramec well rapidly cover the entire Meramec interval with some growth downward into the Woodford. Conversely, microseismicity initiating from a Woodford well clustered in that layer and grew upward into the Lower Meramec with time. Geochemical profiling closely matched the microseismic depth distributions for the associated well landing zones. Similar to the microseismic hydraulic heights from both Upper and Lower Meramec wells consistently produced from the entire Meramec, with additional recovery from the Woodford. Woodford landed wells produced Woodford oil with some production also coming from the Lower Meramec, also consistent with the microseismic depths. These production profiling trends were found to be very consistent across multiple sets of wells drilled into the same target formations. Integrating mapping of hydraulic fracture growth with geochemical assessment of the effective drainage within the hydraulically contacted zones provides unique insights into the reservoir contact and drainage. Understanding the mechanical stratigraphic controls on hydraulic fracture height growth relative to the reservoir drainage is key to informed decisions on wine-rack configurations for optimal reservoir drainage.