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Article
Investigating the Propagation of Multiple Hydraulic Fractures in Shale Oil Rocks Using Acoustic Emission
The propagation of multiple fractures plays a significant role in the effectiveness of hydraulic stimulation in shale oil reservoirs. Previous studies reported that the laminations and bedding interface in sha...
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Article
Numerical simulation of stress regime transformation during unconventional fossil energy development in Sichuan Basin: from strike-slip stress regime to reverse stress regime via hydraulic fracturing
The stress shadow effect of hydraulic fractures not only alters the magnitude and direction of in-situ stress but also switches the stress regime, which affects the fracture propagation pattern and causes inst...
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Article
Simulation of pressure response resulted from non-uniform fracture network communication and its application to interwell-fracturing interference in shale oil reservoirs
The characteristic of the pressure response occurring during dense well spacing hydraulic fracturing in unconventional reservoirs deserves to be investigated, because the effect of the interwell-fracturing int...
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Article
Effects of Gravel Size and Content on the Mechanical Properties of Conglomerate
The conglomerate reservoir in Mahu sag, located in the northwest margin of Junggar basin, China, is of low porosity and permeability. Hydraulic fracturing is necessary to improve oil production efficiency. How...
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Article
Open AccessSpontaneous imbibition in fractal tortuous micro-nano pores considering dynamic contact angle and slip effect: phase portrait analysis and analytical solutions
Shales have abundant micro-nano pores. Meanwhile, a considerable amount of fracturing liquid is imbibed spontaneously in the hydraulic fracturing process. The spontaneous imbibition in tortuous micro-nano pore...
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Article
Open AccessMultiparameter Analysis of Gas Transport Phenomena in Shale Gas Reservoirs: Apparent Permeability Characterization
The large amount of nanoscale pores in shale results in the inability to apply Darcy’s law. Moreover, the gas adsorption of shale increases the complexity of pore size characterization and thus decreases the a...
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Article
Acoustic Emission Characteristics of Sedimentary Rocks Under High-Velocity Waterjet Im**ement
The success of waterjet drilling technology requires further insight into the rock failure mechanisms under waterjet im**ement. By combining acoustic emission (AE) sensing and underwater sound recording tech...
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Article
Novel method for calculating the effective stress coefficient in a tight sandstone reservoir
Determining the influence of effective stress on rock deformation is essential for geotechnical stability analysis in oil and gas production. There is no universal effective stress coefficient for all rock pro...
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Article
Wangfu Low-Permeability Volcanic Gas Reservoir Microstructure and Damage Mechanism
The microstructure of the Wangfu volcanic reservoir and the predicted permeability reduction of this reservoir are investigated. It is found that water block (strata permeability reduction due to the penetrati...
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Article
Evaluation of the Micro-cracks in Shale from the Stress Sensitivity of Ultrasonic Velocities
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Article
Impact of Capillary Imbibition Into Shale on Lost Gas Volume
We have investigated the features of the shale imbibition process for different drilling fluid parameters, using as an example Chang-7 shale in the Yanchang region of Erdos Basin, as is needed to study the eff...
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Article
Active source monitoring at the Wenchuan fault zone: coseismic velocity change associated with aftershock event and its implication
With the improvement of seismic observation system, more and more observations indicate that earthquakes may cause seismic velocity change. However, the amplitude and spatial distribution of the velocity varia...
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Article
Semiannual velocity variations around the 2008 Mw 7.9 Wenchuan Earthquake fault zone revealed by ambient noise and ACROSS active source data
We continuously monitor the long-term seismic velocity variation of one of the major ruptured faults of the devastating 2008 Mw 7.9 Wenchuan earthquake in China from July 2009 to January 2012, jointly using accur...
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Article
Influencing factors of seismic signals generated by un-tuned large volume airgun array in a land reservoir
Un-tuned large volume airgun array in a water reservoir is recently proposed as a new way to generate seismic waves on land. It can be used to explore the earth velocity structure and its temporal variations a...
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Article
Apparent permeability variation of underground water aquifer induced by an earthquake: A case of the Zhouzhi well and the 2008 Wenchuan earthquake
Taking the M2 wave as calibration signals, we extract the phase shifts of the water level relative to the Earth tide in the Zhouzhi well by utilizing the cross-correlation function. And we further obtain the appa...
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Article
A new way to generate seismic waves for continental crustal exploration
An airgun experiment was conducted in a reservoir, with the total volume of the airgun array being 6000 cubic inch. The energy released by one excitation was estimated to be 6.68×106 J, which corresponded to a 3....
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Chapter
Pattern Characteristics of Foreshock Sequences
Earthquake clusterings in both space and time have various forms, in particular, two typical examples are the foreshock sequences and earthquake swarms. Based on the analysis of 8 foreshock sequences in mainla...
