Leakage and increasing fluid pressure detected in Oklahoma's wastewater disposal reservoir

Journal of Geophysical Research
By: , and 

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Abstract

The Arbuckle Group is the principal reservoir used for wastewater disposal in Oklahoma. In Osage County—a seismically quiet part of the state—continuous measurements of fluid pressure reveal that pressure in the reservoir is increasing by at least 5 kPa annually and sometimes at a much higher rate. Tidal analysis reveals that fluid level changes lead the local strain tides, with no apparent influence from transient permeability changes; this indicates a response that is inconsistent with flow in a radially extensive, confined reservoir. We investigate whether this is due to vertical flow to the water table, vertical flow within the Arbuckle, or local distortions from fractures. While none of these alternative models can fully explain both the observed tidal phases and amplitude ratios, the observed response to teleseismic waves supports a mechanism related to leakage rather than fracture effects. At this location fluid influx associated with wastewater disposal is offset by migration into surrounding layers, which include the Precambrian basement below. Thus, our findings suggest the need to monitor for changes in the induced seismicity hazard, while pore pressures increase in a leaky disposal reservoir.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Leakage and increasing fluid pressure detected in Oklahoma's wastewater disposal reservoir
Series title Journal of Geophysical Research
DOI 10.1029/2019JB017327
Issue 124
Year Published 2019
Language English
Publisher American Geophysical Union
Contributing office(s) Earthquake Science Center
Description 24 p.
First page 2896
Last page 2919
Country United States
State Oklahoma
County Osage County