Stress Distribution and Fracture Development Potential in Rocks around Karst Caves in Carbonate Reservoirs
Karst holes and caves are well developed due to karstification in carbonate reservoirs.Stress distribution and fracture development around karst caves are of great significance to evaluate the storage and migration of hydrocarbons in carbonate reservoirs.In this study,the stress distribution and fracture development of Ordovician buried hills in Jizhong depression in northern China were investigated.The rock mechanical parameters of the target area were determined based on logging data and the boundary loads of the target region were also determined.Next,a numerical stress-analysis model was developed to investigate stress around the karst caves in Jizhong depression.Fracture development in the surrounding rocks of the karst caves was also analyzed.Results show that the principle vertical,maximum horizontal,and minimum horizontal stresses of studied area are all compressive with an approximate value of 100 MPa,indicating that the caves are under a stress environment in which mainly the top and lateral sides of caves bear pressure.The stress in the surrounding areas of the caves are quite homogeneous,and the fracture development index in these areas is low,making it difficult to form pathways for oil and gas migration.However,the stress near the top of the caves is relatively larger and the fracture development index is relatively higher,so that the rocks in this area tend to fracture and form migrtion pthy.This stuy is expected to provide scientific basis for the exploitation and development of oil and gas from the carbonate reservoirs in Jizhong depression.
Ziyi Song Yixin Zhang Yongcun Feng Jing LI Luning Sun
School of Geosciences,China University of Petroleum,Qingdao,China Mewbourne School of Petroleum and Geological Engineering,University of Oklahoma,Norman,OK,USA The University of Texas at Austin,TX,USA College of Pipeline and Civil Engineering,China University of Petroleum,Qingdao,China
国际会议
上海
英文
1-5
2018-12-17（万方平台首次上网日期，不代表论文的发表时间）