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系舟山逆冲推覆构造带位于中生代燕山造山带的西南端,分布于系舟山掀斜向斜的北西翼,形成于晚侏罗世晚期,空间上由一系列近平行排列的逆冲断裂组成,剖面上表现为侧幕展布的犁式逆冲断裂所构成的前陡、后缓的单冲式叠瓦状构造。主体由北西向南东方向逆冲,逆冲扩展方式为前展式,运移距离大于5.8km。推覆构造中应力状态在横、纵向上呈现有规律的变化,根带以挤压为主的高角度逆冲断裂及复杂多级褶皱为主;中带以单剪为主,形成叠瓦状构造;锋带挤压作用增强,发育反冲断层和不对称褶皱。随着挤压应力的松弛减弱,山前形成规模较大的正断层。
Department of Zhoushan thrust nappe structure belt located in the southwestern end of the Mesozoic Yanshan orogenic belt, located in the Department of Zhoushan tilt-inclined northwest wing, formed in the late Late Jurassic, the space by a series of nearly parallel arrangement of thrust faults The profile shows the front steep and rear gentle single-shot shingles that are composed of plow-type thrust faults with side curtain spreading. The main body is thrust from northwest to southeast direction, and the thrust expansion mode is foreshortening, with the migration distance greater than 5.8 km. The stress state in the nappe structure showed a regular change in the horizontal and vertical directions. The root belts were dominated by the extrusion-dominated high-angle thrust faults and complex multi-stage folds. The middle strata dominated by single shear and formed a shingle Structure; enhanced frontal extrusion, the development of thrust faults and asymmetric folds. With the relaxation of the compressive stress weakened, a larger normal fault was formed in the piedmont.