In wrench faulted areas, similar to the one introduced here, identifying structural styles and their histories could be one of the most important tasks in studying tectonic related fractures and faults. The main purpose of this paper is to examine the patterns and structural positions of productive fractures in different reservoir structures of the Asmari formation (Oligo-Miocene) in the Khuzistan oil fields belt of southwest Iran. Details of productive fracture positions have been studied on four major Asmari reservoirs, using: production data (e.g., production rates and productivity indices) which are the most reliable indirect fracture identifiers mud losses, to identify open fracture portion faulted well assemblages to find tectonically active portions second derivative map to find the portions of the maximum rate-of-change-of-dip on top of the reservoir structures, where it is expected to have maximum fracture density. The results were then compared with the surface fracture patterns and densities in the mountain front boundary in the area. In general, productive fractures were found to be associated mainly with the plunges and bends of the Asmari reservoir structures. To assist in determining optimal horizontal well trajectories in the anticlinal traps of the studied area, idealized fracture pattern models have been presented in this paper.