Microseismic Imaging of Hydraulically Induced-Fractures in Gas Reservoirs: A Case Study in Barnett Shale Gas Reservoir, Texas, USA

Abstract

Microseismic technology has been proven to be a practical approach for in-situ monitoring of fracture growth during hydraulic fracture stimulations. Microseismic monitoring has rapidly evolved in acquisition methodology, data processing, and in this paper, we evaluate the progression of this technology with emphasis on their applications in Barnett shale gas reservoir. Microseismic data analysis indicates a direct proportion between microseismic moment magnitude and depth, yet no relation between microseismic activity and either injection rate or injection volume has been observed. However, large microseismic magnitudes have been recorded where hydraulic fracturing stimulation approaches a fault and therefore the geologic framework should be integrated in such programs. In addition, the geometry of fracture growth resulted by proppant interactions with naturally fractured formations follows unpredictable fashion due to redirecting the injection fluids along flow paths associated with the pre-existing fault network in the reservoir. While microseismic imaging is incredibly useful in revealing the fracture geometry and the way the fracture evolves, recently several concerns have been raised regarding the capability of microseismic data to provide the fracture dimensional parameters and the fracture mechanism that could provide detailed information for reservoir characterization.

Evaluation of Microseismicity Related to Hydraulic Fracking Operations of Petroleum Reservoirs and Its Possible Environmental Repercussions

“…The maximum number of events was recorded at injection rate of 6.0 m 3 /minute, while the higher average value came slightly later at approximately 8 m 3 /minute. These observations are common in highly fractured tight formations such as those existing in East Texas, where very small displacements causing small magnitudes are numerous near the treatment well vicinity and remarkably decrease as moving away [25]. Such events are replaced by moderate magnitudes of much lower numbers which are usually arranged parallel to the general structural trends.…”

An Overview of New Developments in Shale Gas: Induced Seismicity Aspect

“…The author pointed out the importance of well documenting the specifics of each operation in the ability to get to the root of the observations and described how important that was in the case of pioneering experiments of Denver and Rangely mentioned above. A case study of microseismic imaging of hydraulic fracturing in the Barnett shale gas reservoir in Texas demonstrated some complications about the use of microseismic results in reservoir simulations [36].…”

Fine calculation method for fracture morphology based on microseismic events and its application

“…1 In recent years, while increasing the technological measures for the exploitation of conventional oil and gas resources, more and more attention has been paid to the unconventional oil and gas resources. [3][4][5][6] Microseismic monitoring is an effective method to explain relative parameters of artificial fractures (fracture height, length, azimuth, and zonal coverage) 7,8 and to analyze fracture propagation during fracturing to guide hydraulic fracturing operation. Therefore, hydraulic fracturing technology, and in particular, three-dimensional reconstruction, has been applied to unconventional hydrocarbon development to generate artificial fractures, resulting in increased effective permeability of the reservoir.…”

“…2 During the process of fracturing fluid injection, fractures created by reactivated shears or natural fractures can generate microseismic events. [3][4][5][6] Microseismic monitoring is an effective method to explain relative parameters of artificial fractures (fracture height, length, azimuth, and zonal coverage) 7,8 and to analyze fracture propagation during fracturing to guide hydraulic fracturing operation. [9][10][11][12] In the past few decades, microseismic data have been used to interpret the characteristics of artificial fractures.…”