Determining the mud window, geomechanical model (MEM), and well wall stability analysis, using analytical and numerical methods in one of the wells in Iran’s southwest fields


1 Expert in Geomechanical Studies of National Iranian Drilling Company, Ahvaz, Iran

2 Expert in Petrophysical Studies of National Iranian Drilling Company, Ahvaz, Iran


Nowadays, according to the increase in fuel demand, the oil wells drilling process has increased to exploit the reservoirs. The most important issue in oil and gas wells drilling topic, is the appropriate drilling rate and reducing the cost. Studies and the usage of geomechanical methods can play an important role in this matter. One of the studies regarded to the topic of reducing drilling costs that has received a lot of attention today is the well wall stability and determining the appropriate mud weight to avoid instability in the well wall. In recent years, a lot of research has been done in this field. In the present study, the well wall stability status of one of the excavated wells in Iran’s southwest oil fields, in 88.3 inches, in the upper section of Sarvak Formation was analyzed by using analytical and numerical methods through FLAC3D software. The input parameters in this research are obtained by interpreting the data from Dipole Shear Sonic Imager (DSI), the logs from Formation Micro Imager (FMI), density, caliper and gamma, MDT tools and also from the daily excavation and geology reports. Also, the window for the required mud weight to meet the dissipation situations, fracture opening, well wall symmetric downfalls, and well eruption was determined. The beneficial results of this study can be used to reduce the time spent on excavating the wells in the investigated field in the future, which results in saving drilling costs.


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