Study On The Prediction Of Reef And Reservoir In Changxing Formation In DMP Area Of Eastern Sichuan

Carbonate oil and gas reserves is very important in oil and gas resources in the world,60% of the oil and gas production in the world are from carbonate reserves.The reefs as a kind of special carbonate reservoir,with good porosity,permeability and oil and gas production,high abundance big characteristics.reefs are development in our country and has great exploration prospects.This paper is based on the research object of Changxing formation in DMP area of Sichuan basin.This kind of reef gas reservoir belongs to carbonate lithologic trap.Due to the particularity of its forming conditions,it is characterized by wide distribution and small size and large scale difference;The reservoir is buried deep and are relatively poor in the transverse direction of the reservoir and have a large variation in the longitudinal thickness.The seismic data quality is poor,the seismic response characteristics of the top of Changxing formation are more complex,the same phase axis is chaotic and broken.From the logging curve,some reef reservoirs and surrounding rocks are similar in speed and density,which is not conducive to the separation of reservoir and non-reservoir.Based on geological,logging and seismic data,this paper analyzes the seismic and logging response characteristics of the reef and reservoir in combination with the previous studies.Using seismic facies analysis technique,sedimentary facies analysis technique,seismic attribute analysis technique and Paleogeomorphologic recovery technique to divide the reefs favorable facies belt and to make the prediction of reefs spreading.By logging response characteristics of priority out of the store sensitive parameters,based on the velocity inversion porosity inversion to carry out on the basis of neural network,to pick up reservoir,finally using frequency attenuation technology for exploratory research stored fluid identification.Through the above research,a set of methods for the prediction of reefs reservoirare developed.