Abstract
The pressure regime modeling is an integral part of the well planning and formation evaluation process. An adequate prediction of the estimated pore pressure and better understanding for the pressure regime of any area are important prior drilling any well to optimize the proposed wells target location and enable the well planner to anticipate the location and the potential magnitude of the possible abnormal pressure problems for future drilling plans and consequently minimizing drilling cost.
Wellbore instability, particularly in shale formations, is a major challenge in drilling operations. Many factors such as rock properties, in-situ stresses, chemical interactions between shale and drilling fluids, and thermal effects must be taken into consideration in well trajectory designs and drilling fluid formulations to mitigate wellbore instability-related problems.
Energy dispersive X-ray analysis (EDAX) is a technique used for identifying the elemental composition of a specimen. The EDAX analysis system works as an integrated feature of a scanning electron microscope (SEM).
Identifying shales by X-ray diffraction (XRD) operates on the principle that all minerals and clays are poorly crystalline, exhibit less sharp peaks, because of weathering effects and the substitution of ions at the atomic level crystalline (to some degree)., In contrast Quartz is highly crystalline and with XRD, produces a narrow, sharp peak.,
The paper indicates the degree of integration utilizing both pore pressure data and clay mineralogy to minimizes the uncertainty to properly anticipate drilling challenges and drilling fluids design, in additions it will reveal all XRD and SEM results that define the clay mineralogy and chemistry for Miocene succession in addition to drilling challenges related to each type of clay (bit balling, fine migrates, caved shales and difficulties running the BHA string). The paper will also provide recommendations for drilling fluid design to mitigate drilling challenges and minimize reservoir damage.
Integrating both pore pressure estimation and clay mineralogy determination for specific troublesome formation can minimizes uncertainty for anticipated drilling challenge and proposed solutions.
