Investigations of Natural Bitumen mineralization in Gilan-e- Gharb exploration block, Iran

Abstract

The Gilan-e-Gharb exploration block is structurally located in the Zagros fold-thrust belt, the eastern parts of which are part of the Lurestan sedimentary basin and the western part of the northern Dezful sedimentary basin. This area has been considered as a high prospective area for hydrocarbon resources, due to its deep potential in form of oil and gas, and natural bitumen on surface. Many of the known hydrocarbon sources of Gilan-e-Gharb block are related to anticline structures. The most important factor of controlling natural bitumen placement is the dominant geological structures of Gilan-e-Gharb block. Regarding the frequency of faults and fractures in this area, mineral deposits are controlled by structures of fold. Folding as a container of hydrocarbon material, fracture and fault are responsible for its distribution of the area. Based on this, primarily, after identifying stratigraphy units of mineralization hosts including Gachsaran, Asmari, Pabdeh and Gurpi formations, the main and minor anticlines of Gilan-e-Gharb block were investigated and analyzed. At this stage, monitoring of fractures and faults based on trending were done, then, positioning of these structures relative to folding axis and their stratigraphic sett was prepared as well as placement and distribution of natural bitumen in form of a three-dimensional Structural-Mineralization Modeling. The model is presented in this paper for the first time that could be a new approach to exploration of natural bitumen or gilsonite according to the exact study of the Gilan-e-Gharb exploration block.