In the process of rift-subsidence evolvement,some fault-blocks succession rift and subside for a long period,becoming the host sags of the primary oil source center,and the others show the less range of subsidence or strong denudation,becoming the brink sags,all these just because of the difference in structu.

We found that dot-imprints on cartridge case shoulder,pressing and scraping prints on the edge of cartridge case bottom and marks on the hook of cartridge-case-extractor are all related to the shooting .