A Comprehensive Review of the Applications of Geomechanics in Producing Unconventional Hydrocarbon Reservoirs in North America

Over the past decade, exploitation of unconventional oil and gas reservoirs has enjoyed economic feasibility through abundant usage of horizontal drilling and hydraulic fracturing. One particular type of reservoirs that was subject to heavy investments onshore in the United States is known as shale oil and gas. Due to the enormous size of such reservoirs, the produced hydrocarbon window extends from black oil to volatile oil as well as natural gas and gas condensates in some areas. Eagle Ford, Barnett, Bakken, Marcellous, Niobrara, and Monterey formations are amongst the largest shale oil/gas reservoirs in the United States. Of the newly developed technologies in the industry, applications of geomechanics in horizontal drilling as well as hydraulic fracture design has helped with mitigating the risks involved with drilling the unconventional reservoirs. Geomechanic’s role is highlighted in terms of understanding the stress regimes within the wellbore vicinity; thus helping with drilling and stimulation procedure optimization. To further understand the geomechanical properties of the major unconventional reservoirs in the United States, some examples are introduced in details below. After discussing the properties and statistics accordingly for each shale play, the most common geomechanical tests to understand the stress regime and fracability of the rock units from core samples are reviewed.