Overpressure and Under-Compaction Mechanism Effect on Pore and Fracture Pressure Development of Mauddud Formation, Badra Oil Field, Eastern Iraq

Accurate pore and fracture pressure detection is a major step in successful drilling operations design. The overestimation of these parameters absolutely leads to serious problems throughout and after well drilling. This study is concerned with the characterization and analysis of the most significant diagenetic processes that degrade or improve the reservoir characteristics of the Mauddud Formation in the Badra oil field. The primary goal of this research is to estimate the pore pressure and fracture pressure using well logging data by Techlog 2015 software in order to assess the impact on the estimation of the mud weight window (MWW). The estimated values of formation pressures are then analyzed according to different diagenetic processes affecting the reservoir under study. These important reasons, such as sedimentary texture and original structure, have been analyzed in this study based on the images of both Scanning Electron Microscopy (SEM) and thin section (TS) of many samples taken at different depths of the studied reservoir to cover the vertical changes of the formation. The results show that the value of the safe mud weight window must range from 2.3 to 3.4 ppg, and it becomes narrower and more dangerous when the wells cross the edge of the anticline structure of the reservoir.