Based on analysis of the response characters of log and seismic data,the seismic response mode of "low frequency weak reflector shadow zone" of effective reservoir was established in Dayi structure.

Using polyethersulfones as membrane materials,N-methyl-2-prirodidone(NMP) as a solvent,ethanol as a nonsolvent,NMP-water as the bore solution,the dope solution of PES∶NMP∶Ethanol 35∶57∶8 in wt% was obtained and PES hollow fiber membranes with an ultrathin dense-selective layer for O2/N2 separation were prepared by dry/wet phase separation method.

Study on seismic prediction methods for super tight fractured reservoirs——An example from the exploration of Member 2 of Xujiahe Formation reservoir in Xinchang gas field,Sichuan Basin,China;