Abstract:

 In the development and evolution of the paleokarst, the collapse of paleocave is a common  phenomenon, and the collapsed-paleocave systems are good oil/gas reservoirs. Based on the formation mechanism of karst collapse, this paper illustrates the similarity of paleokarst collapse and karst collapse, then combs the genesis characteristics combined with the formation mechanism and the cause of coalesced collapsed-paleocave systems as high quality reservoirs. The collapsed-paleocave systems can be studied on the basis of characteristics of well drilling, cores, ground penetrating radar, seismic interpretation, conventional logging and FMI imaging logging. As the patterns of collapsed-paleocave systems vary in different geological settings, many problems remain to be resolved. To solve these problems, this paper put forward three proposals that are to be carried out urgently.

Key words: paleokarst reservoir, paleokarst collapse, karst collapse, genesis characteristic