Development planning with low-invasion coring and outcrop studies

Drilling and coring of a discovery well in the Hollin sand, Villano field, in 1992 was followed by low-invasion coring in a confirmation well. A large discrepancy existed in water saturations derived from the capillary pressure and well logs in the discovery well. Also, salinity varied from top to bottom of the reservoir. Reservoir description would be critical to a development plan for the field. Low-invasion coring and outcrop studies were implemented to calculate off-in-place and hydrocarbon reserves. Geostatistical methods were used for shale mapping. Numerical simulation provided an oil-production-rate forecast and the development plan for the field.