Innovative Methodology for Detection of Fracture-Controlled Sweet Spots in the Northern Appalachian Basin. Semi-Annual Technical Progress Report May 31-November 30, 2000.

Jacobi, R. ; Fountain, J. ; Loewenstein, S. ; deRidder, E.

Technical Information Center Oak Ridge Tennessee

关键词: Appalachian Basin;    Detection;    Fractured reservoirs;    Fractures;    Cost effectiveness;   

RP-ID  :  DE2005838891

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

3-D seismic analysis is unquestionably one of the premier methods for obtaining information concerning deep structure, including predictions of enhanced fracture porosity in reservoirs. However, the high cost of 3-D seismic makes it economically unfeasible in many basins with perceived marginal gas reserves. However, without some advanced technology like 3-D seismic, the deep structure in many basins (like the Appalachian Basin of New York State) cannot be critically evaluated because available seismic reflection profiles and deep well logs provide insufficient control. This research project demonstrates a cost-effective alternative to 3-D seismic. The project demonstration is a combination of low-cost, innovative technologies that, when integrated, yield near-3-D quality on a regional scale for identification of fractured reservoir prospects. The study area covers about 760 sq. miles, an area that would cost about $22 million for 3-D seismic coverage alone; our proposal is a fraction of that cost. The basic premise is that highly productive zones in tight reservoirs are associated with discrete zones of intense fracturing, termed 'fracture intensification domains' (FIDs, Jacobi and Fountain, 1996, Jacobi and Xu, 1998). These zones can be identified by integration of surface geology, lineaments, well log data, seismic data and soil gas anomalies. FIDs in the northern Appalachian Basin have been shown to be indicative of fault zones at depth (Jacobi and Fountain, 1996, Jacobi and Xu, 1998). Thus, by identifying and tracing FIDs, we can predict the location of zones of increased fractures in the subsurface. Because large gas discoveries (estimated 3 bcf/well) have been made recently along fault zones in the New York State portion of the Appalachian Basin, it is important to be able to recognize FIDs. Because of vegetation and surficial deposits, the FIDs cannot be traced continuously in outcrop. In order to trace the FIDs, we have developed an integrated program that involves: (1) surface structure, (2) soil gas analyses, (3) remotely-sensed lineaments, (4) existing (2-D) seismics, and (5) aeromagnetics.