Abstract

In the attempt to understand shale gas reservoirs, oil & gas exploration companies are extensively evaluating formation characteristics such as petrophysical and mechanical properties, in-situ stress analysis, and/or gas-in-place estimates. The current demand for field services personnel and equipment, resulting in rising costs, increases the need for effective and efficient field operations, including coring operations.

Coring has been a standard industry practice for years. Although few within the industry would question the need for core material, often the costs associated with coring operations is the primary factor in foregoing sample acquisition. However, the lack of information obtained from core material may prove to be more costly than the coring operation by not fully understanding the reservoir and possibly applying an inappropriate production method.

The primary objective of any coring program should be to obtain cost-effective unaltered samples from formations of interest. Recovering poor quality core, either physically damaged or chemically altered, may compromise core analysis and the objectives of the coring program. It is important to apply the appropriate coring method and core bit to optimize core quality and core recovery. Selecting the appropriate coring system for shale gas exploration program may, at times, be confusing resulting in applying the wrong technique in a given setting wasting money and potential losing valuable data.

This presentation describes various shale gas coring techniques, provides insight into the advancements in coring technologies, and evaluates the coring technologies at various depths, pressures, and project exploration and development needs.