Original paper

Fracture characterization utilizing FMI, velocity deviation logs, core description and thin sections data

Saedi, Ghasem; Soleimani, Bahman; Esmaeilzadeh, Shaghayegh

Abstract

The identification of fractures plays a crucial role in production and development plans of hydrocarbon bearing fields. From a practical point of view, current paper presents an applicable technique to characterize a naturally fractured reservoir utilizing Formation Micro Imager (FMI) and velocity deviation logs, cores and thin sections. The proposed methodology is presented with an application to field information acquired from a carbonate oil field, located in southwest of Iran. To accomplish this, the FMI raw data were processed and interpreted. Then velocity deviation logs and secondary porosity were also measured and compared. Image logs were interpreted in order to extract fractures and moreover statistical analysis has been done to recognize the fracture patterns. The results indicate that stylolites, pores, open and filled micro-fractures are present in the studied reservoir. Fractures are mainly seen as longitudinal and transversal types with high angles rather than to bedding surface. The main porosity system of the reservoir includes inter particle and fractures. According to the presence of oil staining in thin sections, it is revealed that fractures are suitable conduits for fluid flow in same carbonate fractured reservoir. Relationship between derived fracture set with in-situ stresses were examined and distinguished that the maximum horizontal stress (SH max) orientation is consistent with the focal mechanism solutions in Iran from the World Stress Map database.

Keywords

fracturefmi image logvelocity deviation log (vdl)secondary porosityzagros region