Impact of Shut-in Time on Production after Hydraulic Fracturing in Fractured Shale Gas Formation: An Experimental Study

Abstract Hydraulic fracturing is vital in unconventional shale gas development in order to produce economically from the reservoir. An optimum hydraulic fracturing design and operation can be the key difference between good and poor producing well and economics of the well. One of the most common hydraulic fracturing designs is ball drop system. Using ABAQUS software with XFEM method, a three layers model is used to represent overburden formation, shale gas formation and underburden formation. Rock properties, pore pressure and stress data are used as inputs for the generated model. A horizontal well is created in the middle shale gas formation with three fracture stages and 100m perforation spacing between them. Each hydraulic fracture stage is pressurized sequentially based on the treatment plan of ball drop sliding sleeve completion. The simulated hydraulic fractures are evaluated and compared with the measured field data. The comparison of the average wellbore pressure is good as they all showed within 10% of the measured data. The comparison of the hydraulic fracture geometry with the micro-seismicity data is reasonable overall in view of the data evaluation showing considerable uncertainties in the data. The hydraulic fracturing results also show that at 100m perforation spacing and using sequential hydraulic fracturing method (such as ball drop system), the effect of stress shadow is minimal and does not inhibit the fractures growth. However, the stress shadow effect is found to be pronounced for closer spacing between hydraulic fractures. For future application of the developed XFEM hydraulic fracturing model, it can be utilized to design new hydraulic fracturing completion in order to recommend the optimum completion, including perforation spacing, of development wells in unconventional shale gas field.

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In Situ Sequestration of a Hydraulic Fracturing Fluid in Longmaxi Shale Gas Formation in the Sichuan Basin

Energy & Fuels ◽

10.1021/acs.energyfuels.9b00712 ◽

2019 ◽

Vol 33 (8) ◽

pp. 6983-6994 ◽

Cited By ~ 5

Author(s):

Bin Yang ◽

Hao Zhang ◽

Yili Kang ◽

Lijun You ◽

Jiping She ◽

...

Keyword(s):

Hydraulic Fracturing ◽

Shale Gas ◽

Sichuan Basin ◽

Fracturing Fluid ◽

Gas Formation ◽

Longmaxi Shale ◽

The Sichuan Basin ◽

Hydraulic Fracturing Fluid

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Shale, Quakes, and High Stakes: Regulating Fracking-Induced Seismicity in Oklahoma, USA and Lancashire, UK

Case Studies in the Environment ◽

10.1525/cse.2018.001719 ◽

2019 ◽

Vol 3 (1) ◽

pp. 1-14

Author(s):

Miriam R. Aczel ◽

Karen E. Makuch

Keyword(s):

United States ◽

Hydraulic Fracturing ◽

Shale Gas ◽

Seismic Activity ◽

Oil And Gas ◽

Oil And Gas Industry ◽

High Volume ◽

The United States ◽

Horizontal Drilling ◽

Induced Seismic Activity

High-volume hydraulic fracturing combined with horizontal drilling has “revolutionized” the United States’ oil and gas industry by allowing extraction of previously inaccessible oil and gas trapped in shale rock [1]. Although the United States has extracted shale gas in different states for several decades, the United Kingdom is in the early stages of developing its domestic shale gas resources, in the hopes of replicating the United States’ commercial success with the technologies [2, 3]. However, the extraction of shale gas using hydraulic fracturing and horizontal drilling poses potential risks to the environment and natural resources, human health, and communities and local livelihoods. Risks include contamination of water resources, air pollution, and induced seismic activity near shale gas operation sites. This paper examines the regulation of potential induced seismic activity in Oklahoma, USA, and Lancashire, UK, and concludes with recommendations for strengthening these protections.

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