沙埝地区阜宁期构造物理模拟实验

Physical simulation experiment of the structure in Shanian area in Funing stage

为研究沙埝地区阜宁组断裂平面组合及发育顺序,针对斜坡带设计一组物理模拟实验,并从湿度差异的沙、黏土、沙泥混合物中优选出干黏土作为实验材料,详细记录了实验过程,并作出相应的地质解释.实验结果表明:沙埝地区T33反射层上断层以6条近平行的大断层为主干,其中边界处的2条断层形成时间略早于中间4条,在贴近主干断层的位置派生一些与主干断层平行或斜交的低序级断层.工区内大部分断层是在大约NNW334°方向的伸展力下形成的,局部断层受派生剪应力的影响.另外,还讨论了实验材料的湿度和粒度对实验结果的影响.

A set of physical simulation experiments are designed for studying the plane combination and the development sequence of the faults in Shanian area during Funing tectonic stage.Dry clay is chosen as the experimental material from the sand,the clay and their mixture with moisture.The experimental results show that six almost parallel faults are recognized from T33 reflecting layer,they are main faults on the reflecting layer.The two faults in two side boundaries of the area are formed earlier than other four faults in the middle of the area.Some lower-grade faults generate near the main faults,which are parallel to or oblique crossing with the main faults.Most of the faults generated under the effect of the stretching force in about NNW334°,and the faults in partial area are influenced by the derived shear stress field.In addition,the influences of the humidity and the grain size of the experiment material on the experimental results are studied.