Abstract:
A volcaniclastic series of the Early Cretaceous Laiyang Group controlly by NNE trending faults is distributed in the Shichang Zhonglou area in the central sector of the Yishu (Yihe Shuhe) fault. It, with a total thickness of over 6263.71 m, consists dominantly of volcaniclastic turbidites. The sedimentary structures of the sequence are mainly marked by a discontinuous, incomplete Bouma sequence. They originated in a tectonic setting of strong activity of the Yishu fault. On the basis of an integrated study of the structural features of the boundary fault of the basin, migration of the depocenter of the basin and sedimentary characteristics of the turbidites of the Laiyang Group, the paper discusses the relation of the formation of the turbidites of the Laiyang Group with the strike slip movement of the Tanlu (Tancheng Lujiang) fault during the Early Cretaceous.