Method for researching on mud-caprock sealing ability with the use of interval transit times
Fu Guang; Pang Xionqi and Jiaug Zhenxue (Exploration Department , Daqing Petroleum College , Anda City , heilongjiang Province , Postcode：151400)
Restrained by borehole number,coring,experiment cost and so on,people onlyuse limited experimental data to analyse mud-caprock sealing ability,thus greatlyinfluencing on accuracy of caprock evaluation. In order to get more informations ofcaprock sealing,we discuss how to use acoustic interval transit times to analyse thevertical and lateral variations of capillary sealing character in mud caprock,the pressure sealing ability and the formation age by analysing the capillary and pressuresealing mechanisms, and the important influence factors, and by determining thefunction relations between acoustic interval transit time and displacement pressureof mudstone, and between acoustic interval transit time and abnormal pore fluidpressure of mudstone. The method described in the paper offers the reliable basisfor accurately evaluating mud-caprock sealing ability.