Eastern Gas Shales Project: Increasing US Natural Gas Reserves from Eastern Gas-Bearing Shales

摘要

The eastern gas-bearing shales underlie an area of approximately 200,000 square miles in the Appalachian, Michigan, and Illinois basins. Up to 900 trillion cubic feet (tcf) of natural gas are estimated to be contained in the fractures and matrix of these rocks, but only a small percentage is being recovered. The Eastern Gas Shales Project (EGSP) is a comprehensive, multidisciplinary project using existing technical expertise from government agencies, state geological surveys, universities, research institutes, the US Geological Survey, national labs, and private industry. Its overall goal is to advance technology development and commercial production of natural gas from the Devonian Shale. To determine the composition and characteristics of the Eastern Devonian Shales, geological, geochemical, and physical data are being analyzed. An inventory of the total natural gas resource, determination of the economically recoverable resource, and identification of new exploration techniques for locating gas-filled fractured shale reservoirs are part of this activity. Some wells in the Devonian Shales produce naturally at economic rates, but most have to be stimulated to increase the flow rate for commercial production. The flow of gas from the shale matrix to the wellbore through the fractures is slow because of the very low permeability of shale rock. Stimulation techniques are directed at increasing the number of fractures in the shale connected to a wellbore. Conventional and new stimulation techniques are being tested and evaluated by EGSP contractors. Sites are selected, drilling and stimulation are monitored and performance is evaluated. A critical phase of the EGSP is to see that feasible ideas and information are disseminated and usable techniques and devices are implemented. The EGSP attempts to accelerate the usual process and to encourage the private sector to develop the unconventional natural gas from Devonian Shale. (ERA citation 08:023072)