Automatic fault extraction based on α-shape and polygon offset
Fault interpretation is crucial in reservoir prediction and geological modeling.Currently,fault inter-pretation is mostly conducted manually,with a large workload and low efficiency,which fails to meet the pre-cise requirements of oilfield exploration and development.Therefore,based on the analysis and optimization of the traditional coherent attributes or intelligent fault prediction data volumes,this paper proposes an automatic fault extraction method based on α shape and polygon offset.Firstly,it determines the location of the target fault through human-computer interaction.Secondly,it develops an α-shape breakpoint edge extraction algo-rithm and an inclination constrained polygon offset algorithm to accurately depict the spatial boundary of faults.Finally,by using the spatial boundary as a constraint condition and setting a target fault coincidence threshold,the extension range of the region growth algorithm is constrained to complete the automatic extraction of 3D faults.The application of the proposed method has achieved great results in many areas of Shengli Oilfield.The spatial distribution pattern of faults is depicted in Zheng 6 area,and the fault integrity and accuracy are sig-nificantly better than a certain commercial software.The automatic extraction of faults has greatly improved work efficiency in Xin 50 area.