The Physical Simulation Experiments For Formation And Evolution Of Clay Smear

The aim of this study is to improve our knowledge of the processes that lead to clay smear during faulting of a layered sand-clay sequence in an analogue sandbox model. Based on our existing experimental conditions and advanced construction abroad, we designed and made a physical sandbox. Combined the actual rock physical properties and similarity, finally we determine which is the ideal material for clay smear simulation experiment. The dry clay for the first time was used to simulation the earth’s crust of the plastic layer, the ruselt turn out to be so exciting. Each experiment has only one parameter which affecting the clay smear, such as, clay layer thickness, ratio of clay, competence and combinations. Application of PIV(Particle Image Velocimetry) technology for experimental model to calculate the distribution of shear strain and the change in section, the development of fault characteristics and the formation of clay smear evolution is discussed. By comparing similar experiments, we find out the factor which effect the clay smear so much. Through all of the experiments confirmed that is the most easy to lose the continuity of clay smear is footwall cutoffs. With the increasing of ratio of clay in sand-clay sequence, the continuity is increased. In a layered sandstone and shale sequence, the competence constraction between sand-clay and other clayers is strong enough to affect the clay smear.