Changes in deep groundwater flow patterns related to oil and gas

This is a Preprint and has not been peer reviewed. The published version of this Preprint is available: https://doi.org/10.1111/gwat.13136. This is version 1 of this Preprint.

Downloads

Download Preprint

Authors

Keegan Jellicoe, Jennifer C McIntosh , Grant Ferguson 

Abstract

Large volumes of saline formation water are both produced from and injected into sedimentary basins as a by-product of oil and gas production. Despite this, the location of production and injection wells has not been studied in detail at the regional scale and the effects on deep groundwater flow patterns (i.e. below the base of groundwater protection) possibly driving fluid flow towards shallow aquifers remain uncertain. Even where injection and production volumes are equal at the basin scale, local changes in hydraulic head can occur due to the distribution of production and injection wells. In the Canadian portion of the Williston Basin, over 4.6 x 109 m3 of water has been co-produced with 5.4 x 108 m3 of oil, and over 5.5 x 109 m3 of water has been injected into the subsurface for saltwater disposal or enhanced oil recovery (EOR). Despite approximately equal values of produced and injected fluids at the sedimentary basin scale over the history of development, cumulative fluid deficits and surpluses per unit area in excess of a few 100 mm are present at scales of a few 100 km2. Fluid fluxes associated with oil and gas activities since 1950 likely exceed background groundwater fluxes in these areas. Modelled pressures capable of creating upward hydraulic gradients are predicted for the Midale Member and Mannville Group, two of the strata with the highest amounts of injection in the study area. This could lead to upward leakage of fluids if permeable pathways, such as leaky wells, are present.

DOI

https://doi.org/10.31223/X5ZK7M

Subjects

Engineering, Physical Sciences and Mathematics

Keywords

groundwater, oil and gas, induced seismicity, injection wells, produced water, disposal wells

Dates

Published: 2021-09-17 17:02

Last Updated: 2021-09-18 00:02

License

CC0 1.0 Universal - Public Domain Dedication

Additional Metadata

Data Availability (Reason not available):
Injected and produced volume derived from commercial database maintained by by IHS.

Add a Comment

You must log in to post a comment.


Comments

There are no comments or no comments have been made public for this article.