Advanced Technique of Rock Typing Characterization of Mishrif Formation, Amara Oil Field in Southern Iraq

Abstract

Reservoir rock typing integrates geological, petrophysical, seismic, and reservoir data to identify zones with similar storage and flow capacities. Therefore, three different methods to determine the type of reservoir rocks in the Mushrif Formation of the Amara oil field. The first method represents cluster analysis, a statistical method that classifies data points based on effective porosity, clay volume, and sonic transient time from well logs or core samples. The second method is the electrical rock type, which classifies reservoir rocks based on electrical resistivity. The permeability of rock types varies due to differences in pore geometry, mineral composition, and fluid saturation. Resistivity data are usually obtained from well logs, and resistivity logs are available. The third method is the storage capacity of rocks. The focus is on the ability of rocks to store liquids, especially hydrocarbons. This method analyzes porosity, permeability, and pore size distribution data. After that, we compared the previous three methods to identify the types of rocks and determine the best method. In the first method (Cluster Analysis), three types of rocks were identified (Bad, Moderate, and Good). In the second method, electrical rock type (ERT), four types of rocks were identified (Bad, Moderate, Good, and Very good). Then, the third method (Storage Capacity) came and enhanced the results of the second method, so the second method is considered the best and most accurate method determining the types of rocks.