PHYSICAL EXPERIMENTAS ON STRIKE-SLIP FAULT AND PULL-APART BASIN

According to the theory that plastic flow of the lower layer (including lower crust and upper mantle lithosphere) controls upper layer (upper crust) deformation in the multi-layer lithosphere, the paper studies the physical experiments of strike-slip fault and pull-apart basin adopted ductile/brittle double-layers model. The experiment results show that strike-slip model developed sinistral right-step fault zone which consisted of a lot of "S"-type faults during sinistral strike-slip stage. The early fault zone was reconstructed and became dextral right-step "Z"-type fault during dextral strike-slip stage.There are three-type extensions in the strike-slip fault zone:(1) a lot of diamond basins formed with stretching of "S"-type fault; (2) the "graben-horst" structure appeared when the ends of adjacent "S"-faults were sheared and connecting; (3) the pull-apart basins formed along right steps of dextral faults during the second strike-slip stage. The stretching faults formed in the stage of uplifting limit the location and the direction of strike-slip faults.Strength of brittle-layer restricts the forming and the development of strike-slip faults, and the texture of brittle-layer influences coupling of brittle-plastic layers and characters of strike-alip faults.