Prediction of Structural Fractures in Olituoz Volcanic Rocks, Liaohe Field, Northeast China

Fangfeng Xiao, Guiting Hou, Zhongyi Ding, Yadong Zheng, and Xianglin Qian

The key point to study and explore fracture-related reservoirs lies on awareness of fracture development. Prediction of structural fractures based on Finite Element Method (FEM) sheds new light on this tricky problem and this method is applied to Eocene Olituoz volcanic rocks, Liaohe Field, northeastern China. Fracture value is calculated, which is the common method, based on simulated stress field of Olituoz area, rock strength value and fracture criteria. Meanwhile, strain energy related to fracture initiation is also calculated, which is defined as energy value. However, both values do not fit well with the statistical density of structural fractures from the core rock samples available. Because in reality both the two factors--stress and strain energy, are involved in the forming process of fractures. Hence, a method named "Bio-Factor Method" which concerns both stress and strain is adopted here and the simulation data fits the statistic data fairly better. Development and distribution of structural fractures is controlled or strongly affected by the pre-existing fault system in the region. Based on the prediction results, several areas with high potential of structural fracture development are recommended for petroleum exploration.