Fine Characterization Of Farewell Complex Fault Block In The Wennan Oilfield

Wennan oilfield is located on central uplift zone of Dongpu depression,which lies in the later period of exploration now.The major oil reservoir has been developed successively,and its potentiality of exploration and development lies maily in the constructional joints,complex fault zones and deep zones.These blocks has complex structures and abundant low-level faults,hence it is difficult for us to make accurate structure interpretation.Aiming at geological characteristics and challenges of Wennan area,it is vitally important for reservoir development of complex fault blocks to study systematically low-level faults systems in Wennan oilfield,apply the skills of accurate structure interpretation.In this paper regional structure is analised and studied,genetic types of low-level faults of Wennan oilfield are summarized,and accurate interpretation skills are established to apply in complex blocks.The response characteristic of low-level faults are obtained in Wennan oilfield through forward modeling with high accurate seismic data,then it can be used to interpret low-level faults,seismic datum are handled through structural smoothing in order to reduce noise and influence of reservoir response characteristic.Seismic datum are handled smoothly to obtain variances,meanwhile faults distributional characteristics of Wennan oilfield are analised through geological statistics to recognize distribution rules of fault systems.Based on above methods variance parameters are obtained and optimized,and algorithm are obtained to optimize variance.Traditional ant tracing contained overall workflow of fault interpretation,however good effectiveness always can not be made.In order to raise recognizing accuracy for low-level faults,variances are ant traced through multiple ant tracing in this paper.Results shows that multiple ant tracing can raise recognizing accuracy in complex fault blocks of Wennan oilfield.Lastly mixing frenquency occurrence of RGB is introduced into analysis of seismic frequency divider,properties of different bands without overlapping are displayed together,similar energy characteristic areas are emphasized in order to softening differences and displaying community,then recognizing accuracy of low-level faults is raised.