Impact of Completion System, Staging, and Hydraulic Fracturing Trends in the Bakken Formation of the Eastern Williston Basin

2012 ◽  
Author(s):  
Randy Lafollette ◽  
William David Holcomb ◽  
Jorge Aragon
Keyword(s):  
Hydraulic Fracturing ◽  
Williston Basin ◽  
Bakken Formation

The role of preexisting fractures and faults during multistage hydraulic fracturing in the Bakken Formation

2014 ◽  
Vol 2 (3) ◽  
pp. SG25-SG39 ◽  
Author(s):  
Yi Yang ◽  
Mark D. Zoback
Keyword(s):  
Hydraulic Fracturing ◽  
Pore Pressure ◽  
Well Being ◽  
Williston Basin ◽  
Bakken Formation ◽  
Multistage Hydraulic Fracturing ◽  
Geomechanical Analysis ◽  
Microseismic Events ◽  
Observation Wells

We performed an integrated study of multistage hydraulic fracture stimulation of two parallel horizontal wells in the Bakken Formation in the Williston Basin, North Dakota. There are three distinct parts of this study: development of a geomechanical model for the study area, interpretation of multiarray downhole recordings of microseismic events, and interpretation of hydraulic fracturing data in a geomechanical context. We estimated the current stress state to be characterized by an NF/SS regime, with [Formula: see text] oriented approximately [Formula: see text]. The microseismic events were recorded in six vertical observation wells during hydraulic fracturing of parallel wells X and Z with three unusual aspects. First, rather than occurring in proximity to the stages being pressurized, many of the events occurred along the length of well Y, a parallel well located between wells X and Z that had been in production for approximately [Formula: see text] years at the time X and Z were stimulated. Second, relatively few fracturing stages were associated with an elongated cloud of events trending in the direction of [Formula: see text] as was commonly observed during hydraulic fracturing. Instead, the microseismic events in a few stages appeared to trend approximately [Formula: see text], approximately 30° from the direction of [Formula: see text]. Earthquake focal plane mechanisms confirmed slip on faults with this orientation. Finally, the microseismic events were clustered at two distinct depths: one near the depth of the well being pressurized in the Middle Bakken Formation and the other approximately [Formula: see text] above in the Mission Canyon Formation. We proposed that steeply dipping N75°E striking faults with a combination of normal and strike-slip movement were being stimulated during hydraulic fracturing and provided conduits for pore pressure to be transmitted to the overlaying formations. We tested a simple geomechanical analysis to illustrate how this occurred in the context of the stress field, pore pressure, and depletion in the vicinity of well Y.

Eight-Plus Years of Hydraulic Fracturing in the Williston Basin: What Have We Learned?

2016 ◽  
Author(s):  
Karthik Srinivasan ◽  
Jayanth Krishnamurthy ◽  
Ryan Williams ◽  
Pavan Dharwadkar ◽  
Tyler Izykowski ◽  
...  
Keyword(s):  
Hydraulic Fracturing ◽  
Williston Basin

Microseismic Magnitudes and b-Values for Delineating Hydraulic Fracturing and Depletion

SPE Journal ◽  
2017 ◽  
Vol 22 (05) ◽  
pp. 1624-1634 ◽  
Author(s):  
T.. Dohmen ◽  
J.. Zhang ◽  
L.. Barker ◽  
J. P. Blangy
Keyword(s):  
Hydraulic Fracturing ◽  
Qualitative Assessment ◽  
Williston Basin ◽  
Oil Well ◽  
B Values ◽  
Relative Contribution ◽  
Microseismic Activity ◽  
Shear Slip ◽  
Microseismic Events ◽  
Well Completions

Summary In 2014, Hess Corporation collected microseismic and hydraulic-fracturing data in a Bakken field trial near an existing oil well in the Williston Basin of North Dakota. In addition to monitoring the microseismic activity of the newly drilled offset-well completions, the field test delineated the depletion surrounding the original well by slowly repressurizing it. This repressurization induced shear-slip events, which preferentially delineated the depleted zone of the producer well, a process we call microseismic depletion delineation (MDD). By comparing the magnitudes of the depletion-related events to those that accompanied the new offset completions, we observe that higher magnitude microseismic events occur within the depleted interval. This paper offers an explanation for why higher magnitudes appear in the depleted zone and suggests that measuring magnitude statistics in the form of b-values can provide a qualitative assessment of the relative contribution of oil from completions along a wellbore.

Sign in / Sign up

Export Citation Format

Share Document