已发表: 10/01/2012
已发表: 10/01/2012
China’s Ordos basin, the second-largest sedimentary basin in the country, has proven reserves estimated at 10 billion tons. Historically, field development has been economical, but due to low permeability, many of the wells have had low yields. To increase recovery, PetroChina Changqing partnered with Schlumberger to increase effective fracture surface area, optimize fracture placement, and apply horizontal drilling techniques in two wells
Schlumberger recommended the unconventional 3D fracturing design workflow within Mangrove software to help optimize completion and fracturing designs—without replacing the existing multistage fracturing tool. The team built a 3D reservoir model from log correlations and interpretations, as well as seismic and reservoir studies.
From there, the unconventional fracture model simulated complex fractures based on fractureinduced stress shadows and interactions between hydraulic and natural fissures. PetroChina Changqing and Schlumberger selected optimal fracture placements based on reservoir and completion quality. StimMAP LIVE microseismic monitoring service helped engineers optimize fracture placement and fracture surface area during each stage of the treatment.
After 3 months, the horizontal wells optimized with Mangrove software showed 50% higher stabilized production rates than the previous-best offset well. PetroChina Changqing identified the completion workflow as a key to the campaign’s success—from both production and operational standpoints. The success of these jobs led PetroChina Changqing to use the pilot wells as a template for future tight oil development in the Ordos basin.
"Initial production tests for these two pilot wells show 3.6 and 4.4 times higher production with half the reservoir-to-wellbore pressure drawdown of vertical wells on the same pad."
-Xu Yong Gao, Deputy Chief Engineer, PetroChina Changqing
Challenge: Increase oil recovery in tight sand reservoirs by using horizontal drilling techniques, improving fracture placement, and enhancing fracture surface area.
Solution: Use Mangrove engineered stimulation design to build a 3D reservoir model and simulate complex fractures based on interactions between hydraulic fractures and natural fissures.
Results:
