46th U.S. Rock Mechanics/Geomechanics Symposium,
2012. American Rock Mechanics Association
2 in the last 30 days
390 since 2007
Show more detail
ARMA Member Price:
ARMA Non-Member Price:
Several vertical and horizontal exploration wells drilled in the West Kazakhstan field that are located on the Northern margin of the Pre-Caspian Basin, show significant wellbore-stability problems including stuck pipe and mud-shale interactions. A numerical model was developed to diagnose the source of these problems and implement a successful development plan considering the variation of the local in situ stresses, temperature alteration, shale-fluid physicochemical interactions and the effect of the induced fluid flow. The magnitude and orientations of the in-situ stresses, formation properties and strength of the formations drilled have been extensively studied. A field geological model was utilized in conjunction with the well log and drilling data from several of the exploration wells to obtain accurate input parameters for the integrated model. The wellbore-stability model was calibrated using drilling, pressure and cutting data. An integrated risk analysis study, incorporating borehole stability, lost circulation, hole cleaning and differential sticking was implemented to effectively plan future drilling operations in the field and to maximize the drilling margin. History matching for the observed field wellbore-instability cases was conducted using the proposed coupled model, optimizing the drilling fluid programs and well trajectories to minimize the instability problems in future wells in the study area. Based on outcomes of this study, recommendations for field development have been made to reduce non-productive time during drilling operations resulting in sizable cost reduction.
The West Kazakhstan field is located on the Northern margin of the Pre-Caspian Basin. The Pre-Caspian basin covers an area of approximately 550,000 km2 and is a large, deeply subsided portion of the Russian Platform. The structural map of the North Pre-Caspian Basin is illustrated in Figure 1. The West Kazakhstan field experienced a basement-related block faulting throughout the Paleozoic period within uplift zones.
Number of Pages
Looking for more?
Some of the OnePetro partner societies have developed subject- specific wikis that may help.