Publications

Chevron Indonesia plans to complete several deviated wells in the Seturian field, offshore East Kalimantan and conducted a joint sand production risk study with Schlumberger. We used existing relevant logs, drilling and other data to construct a calibrated Mechanical Earth Model (MEM) and used it to evaluate sand production risk over the life of the field, i.e. under depleting reservoir pressure. The MEM includes estimates of stress magnitudes and orientations, pore pressure and formation elastic and mechanical properties. We used core test data from the Seturian-1ST well to calibrate rock mechanical property correlations while MDT measurements, drilling observations and caliper logs provided calibration data for the pore pressure and horizontal stresses. The calibrated MEM showed that, while most of the planned perforated intervals will be stable over the expected life of the reservoir, other sands are likely to produce sand at some point. We modeled alternative completion configurations and showed that much of the sanding risk could be avoided by selective perforating. Moreover, in wells that are deviated more than about 30o, oriented perforating will further increase the envelope of sand free production conditions. Sand F in SRN-2 was gun stack TCP perforated (non-oriented) at an estimated under balance of 1660 psi and successfully produced from April until October 2009 when subsequent, additional balanced e-line perforations were added. To date there have been no indications of sand production. This experience was consistent with sand risk predictions based on our model. Chevron used the study results to optimize designs for two planned wells and to optimize completion intervals and orientations for those intervals that are at risk of sanding. The model indicates that the optimized completions are unlikely to produce sand over the planned life of the reservoir, to the planned abandonment pressure of 450 psi (i.e. 86% depletion).