Volume fracturing technology on horizontal well in Shulu tight oil

Low-permeability to ultralow-permeability reservoirs of the China National Petroleum Corporation are crucial to increase the reserve volumes and the production of crude oil in the present and future times. This study aimed to address the two major technical bottlenecks faced by the low-permeability to ultralow-permeability reservoirs by a comprehensive use of technologies and methods such as rate-controlled mercury injection, nuclear magnetic resonance, conventional logging, physical simulation, numerical simulation, and field practices. The reservoir characteristics of low-permeability to ultralow-permeability reservoirs were first analyzed. The water flooding development adjustment mode in the middle and high water-cut stages for the low-permeability to ultralow-permeability reservoirs, where water is injected along the fracture zone and lateral displacement were established. The formation mechanism and distribution principles of dynamic fractures, residual oil description, and expanding sweep volume were studied. The development mode for Type II ultralow-permeability reservoirs with a combination of horizontal well and volume fracturing was determined; this led to a significant improvement in the initial stages of single-well production. The volume fracturing core theory and optimization design, horizontal well trajectory optimization adjustment, horizontal well injection-production well pattern optimization, and horizontal well staged fracturing suitable for reservoirs with different characteristics were developed. This understanding of the reservoir characteristics and the breakthrough of key technologies for effective development will substantially support the oil-gas valent weight of the Changqing Oilfield to exceed 50 million tons per year, the stable production of the Daqing Oilfield with 40 million tons per year (oil-gas valent weight), and the realization of 20 million tons per year (oil-gas valent weight) in the Xinjiang Oilfield.

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The Research of Gas Flooding of Horizontal Well with SRV in Tight Oil Reservoir

Journal of Petroleum & Environmental Biotechnology ◽

10.4172/2157-7463.1000197 ◽

2015 ◽

Vol 06 (01) ◽

Author(s):

Xiaoliang Zhao Xinwei Liao

Keyword(s):

Horizontal Well ◽

Tight Oil ◽

Oil Reservoir ◽

Gas Flooding ◽

Tight Oil Reservoir

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A multi-linear transient pressure model for multistage fractured horizontal well in tight oil reservoirs with considering threshold pressure gradient and stress sensitivity

Journal of Petroleum Science and Engineering ◽

10.1016/j.petrol.2018.08.078 ◽

2019 ◽

Vol 172 ◽

pp. 839-854 ◽

Cited By ~ 17

Author(s):

Zhongwei Wu ◽

Chuanzhi Cui ◽

Guangzhong Lv ◽

Shaoxian Bing ◽

Gang Cao

Keyword(s):

Pressure Gradient ◽

Horizontal Well ◽

Stress Sensitivity ◽

Oil Reservoirs ◽

Tight Oil ◽

Threshold Pressure ◽

Transient Pressure ◽

Threshold Pressure Gradient ◽

Fractured Horizontal Well ◽

Tight Oil Reservoirs

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The Performance Evaluation of Old Well after SRV in Ordos Basin Tight Oil Reservoir

10.2118/spe-169968-ms ◽

2014 ◽

Author(s):

H.. Wang ◽

X.. Liao ◽

H.. Ye ◽

X.. Zhao ◽

C.. Liao ◽

...

Keyword(s):

Evaluation Method ◽

Ordos Basin ◽

Fracture Network ◽

Water Flooding ◽

Tight Oil ◽

Oil Reservoir ◽

Well Test ◽

Stimulated Reservoir Volume ◽

Tight Oil Reservoir ◽

Volume Fracturing

Abstract The technology of Stimulated reservoir volume (SRV) has been the key technology for unconventional reservoir development, it can create fracture network in formation and increase the contact area between fracture surface and matrix, thus realizing the three-dimensional stimulation and enhancing single well productivity and ultimate recovery. In China, the Ordos Basin contains large areas of tight oil reservoir with the porosity of 2~12 % and permeability of 0.01~1 mD. The most used development mode is conventional fracturing and water flooding, which is different from the natural depletion mode in oversea, but the development effect is still unfavorable. The idea of SRV is proposed in nearly two years in Changqing Oilfield. SRV measures are implemented in some old wells in tight oil formation. It is a significant problem that should be solved urgently about how to evaluate the volume fracturing effect. Based on the real cases of old wells with SRV measures, the microseismic monitoring is used to analyze the scale of formation stimulation and the complexity of fracture network after volume fracturing; the numerical well test and production data analysis (PDA) are selected to explain the well test data, to analyze the dynamic data, and to compare the changes of formation parameters, fluid parameters and plane streamlines before and after volume fracturing; then the interpretation results of well test with the dynamic of oil and water wells are combined to evaluate the stimulation results of old wells after SRV. This paper has presented a set of screening criteria and an evaluation method of fracturing effect for old well with SRV in tight oil reservoir. It will be helpful to the selection of candidate well and volume fracturing operation in Ordos Basin tight oil reservoir. It should be noted that the evaluation method mentioned in the paper can be expanded to volume stimulation effect evaluation in other unconventional reservoirs, such as tight gas, shale gas and so on.

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