Abstract: The studies on the development laws of tectonic fractures in sandstones are significant to the reservoir prediction. In order to better know the development and distribution of tectonic fractures around the fault related folds, this paper studied the relationship between tectonic fracture density and its distance to the fault with the examples of a fault bend fold and a fault propagation fold developed in the Jurassic sandstones of the Kuqa Depression. The results show that (1) an exponential relationship between tectonic fracture density and its distance to the fault is established, and the tectonic fracture density decreases as the distance from the fault increases; (2) there is a damaging region where the tectonic fracture density decreases sharply, and this region is a fracture zone controlled by the fault related fold, which is named a“s fault and hinge controlling tectonic fracture zone”. The recognition of this tectonic fracture zone is of great importance to the quantitative study of tectonic fractures and numerical simulation of reservoir.

Key words: fault related folds, tectonic fractures, sandstone, Kuqa Depression