Reservoir rocks in Bashijiqike Fm outcrop are mostly of medium-grained lithic sandstone

dominated by the secondary dissolved micropores

strong-medium cementation

and weak-medium dissolved diagenetic facies. There are three genetic types of sand bodies in the Bashijiqike Fm

including sandy-braided channel sand bodies in the braided-delta plain in the 2nd member of Bashijiqike Fm

gravel-braided channel sand bodies in the braided-delta plain in the 1st member of Bashijiqike Fm

and fan delta reservoir sand bodies in the 3rd member of the Fm. On the basis of reservoir sand bodies' prototype-model

the reservoirs' architectural structure of Bashijiqike Fm outcrop can be divided into 6-grade hierarchical interfaces and 6-grade hierarchical entities

and the framework structure is of “building block” pattern. Single sand body occurs generally as tabular mass or wide lens.By contrasting with those in the subsurface

sand bodies in the outcrop area might be a little bit coarser

with higher cement content

and worse reservoir quality.The obvious differences between them might be caused by the epidiagenesis in the outcrop.