Multi-attribute Prediction Of Crack Based On Dip Control

As part of China’s old oil field entry into the phase of detailed seismic exploration,people become notice the unconventional reservoirs and the reasonable extracting of residual oil.The percentage of fractured oil and gas reservoirs are increased rapidly.In the exploration and development of fractured reservoirs,we find that fracture can enhance the reservoir’s function,such as increasing the oil and gas accumulation space and the petroleum migration pathway,which is good at producing oil or gas.The accurate degree of the reservoir fracture distribution and the development of features determines whether the exploration and development of fractured reservoirs can be successful.The structure of the crack is small and complex.If we want to develop the fractured reservoir efficiently,we should recognize and predict the fracture in the reservoir accurately.The method for crack prediction we know,mainly include the core observation method in geology,analysis of logging data and the earthquake forecast method.In this paper,we convert the original seismic data volume to the Steering-Cube.Then,we calculate azimuth,dip,curvature and coherence attribute in the Steering-Cube.The Steering Cube is obtained by a dip and azimuth scan method,which contains information about each point in the seismic volume.This post-processing technique can greatly reduce the random disturbance,enhanced reflection and improve the continuity of the event.So as to improve the signal to noise ratio of seismic data,and improve the quality of seismic data,and improve the accuracy of crack prediction.In this paper,a comprehensive analysis is made on the extracted attributes.Compare the forecast result to the situ stress data,which is used to verify the accuracy of the analysis results.After determine the distribution of fracture zones within the study area of the target layer,it can provide a reliable basis to the drill distribution in the next step.By means of the analysis of the similarity of seismic waveform,we obtain an estimate of seismic coherence.A place with a strong discontinuity has a low correlation coefficient,which can be a good characterization of discontinuity structure information,such as fault and fracture.So it is widely used in fault interpretation and fracture prediction.The curvature is the main index to reflect the degree of curvature of space curve or curved surface.Stratum deforms under the stress.In general,area with high curvature have the higher regional tectonic stress.Therefore,the small faults and cracks are more developed.And then,we can predict fracture based on the curvature properties.