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Title: Characterization and simulation of an exhumed fractured petroleum reservoir. Final report, March 18, 1996--September 30, 1998

Abstract

An exhumed fractured reservoir located near Alligator Ridge in central Nevada provides the basis for developing and testing different approaches for simulating fractured petroleum reservoirs. The fractured analog reservoir comprises a 90 m thickness of silty limestone and shaly interbeds within the Devonian Pilot Shale. A period of regional compression followed by ongoing basin and range extension has created faults and fractures that, in tern, have controlled the migration of both oil and gold ore-forming fluids. Open pit gold mines provide access for observing oil seepage, collecting the detailed fracture data needed to map variations in fracture intensity near faults, build discrete fracture network models and create equivalent permeability structures. Fault trace patterns mapped at the ground surface provide a foundation for creating synthetic fault trace maps using a stochastic procedure conditioned by the outcrop data. Conventional simulations of petroleum production from a 900 by 900 m sub-domain within the reservoir analog illustrate the possible influence of faults and fractures on production. The consequences of incorporating the impact of different stress states (e.g., extension, compression or lithostatic) are also explored. Simulating multiphase fluid flow using a discrete fracture, finite element simulator illustrates how faults acting as conduits might be poorlymore » represented by the upscaling procedures used to assign equivalent permeability values within reservoir models. The parallelized reservoir simulators developed during this project provide a vehicle to evaluate when it might be necessary to incorporate very fine scale grid networks in conventional reservoir simulators or to use finely gridded discrete fracture reservoir simulators.« less

Authors:
; ;
Publication Date:
Research Org.:
Univ. of Utah, Salt Lake City, UT (United States)
Sponsoring Org.:
USDOE Assistant Secretary for Fossil Energy, Washington, DC (United States)
OSTI Identifier:
307859
Report Number(s):
DOE/PC/91008-18
ON: DE98000497; TRN: AHC29905%%36
DOE Contract Number:
AC22-94PC91008
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Dec 1998
Country of Publication:
United States
Language:
English
Subject:
02 PETROLEUM; PROGRESS REPORT; NEVADA; FRACTURED RESERVOIRS; PETROLEUM DEPOSITS; GEOLOGIC MODELS; TECTONICS; GEOLOGIC FAULTS; GEOLOGIC FRACTURES; MAPPING; MULTIPHASE FLOW

Citation Formats

Forster, C.B., Nielson, D.L., and Deo, M. Characterization and simulation of an exhumed fractured petroleum reservoir. Final report, March 18, 1996--September 30, 1998. United States: N. p., 1998. Web. doi:10.2172/307859.
Forster, C.B., Nielson, D.L., & Deo, M. Characterization and simulation of an exhumed fractured petroleum reservoir. Final report, March 18, 1996--September 30, 1998. United States. doi:10.2172/307859.
Forster, C.B., Nielson, D.L., and Deo, M. Tue . "Characterization and simulation of an exhumed fractured petroleum reservoir. Final report, March 18, 1996--September 30, 1998". United States. doi:10.2172/307859. https://www.osti.gov/servlets/purl/307859.
@article{osti_307859,
title = {Characterization and simulation of an exhumed fractured petroleum reservoir. Final report, March 18, 1996--September 30, 1998},
author = {Forster, C.B. and Nielson, D.L. and Deo, M.},
abstractNote = {An exhumed fractured reservoir located near Alligator Ridge in central Nevada provides the basis for developing and testing different approaches for simulating fractured petroleum reservoirs. The fractured analog reservoir comprises a 90 m thickness of silty limestone and shaly interbeds within the Devonian Pilot Shale. A period of regional compression followed by ongoing basin and range extension has created faults and fractures that, in tern, have controlled the migration of both oil and gold ore-forming fluids. Open pit gold mines provide access for observing oil seepage, collecting the detailed fracture data needed to map variations in fracture intensity near faults, build discrete fracture network models and create equivalent permeability structures. Fault trace patterns mapped at the ground surface provide a foundation for creating synthetic fault trace maps using a stochastic procedure conditioned by the outcrop data. Conventional simulations of petroleum production from a 900 by 900 m sub-domain within the reservoir analog illustrate the possible influence of faults and fractures on production. The consequences of incorporating the impact of different stress states (e.g., extension, compression or lithostatic) are also explored. Simulating multiphase fluid flow using a discrete fracture, finite element simulator illustrates how faults acting as conduits might be poorly represented by the upscaling procedures used to assign equivalent permeability values within reservoir models. The parallelized reservoir simulators developed during this project provide a vehicle to evaluate when it might be necessary to incorporate very fine scale grid networks in conventional reservoir simulators or to use finely gridded discrete fracture reservoir simulators.},
doi = {10.2172/307859},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Dec 01 00:00:00 EST 1998},
month = {Tue Dec 01 00:00:00 EST 1998}
}

Technical Report:

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  • This report summarizes research conducted for the Fractured Reservoir Discrete Feature Network Technologies Project. The five areas studied are development of hierarchical fracture models; fractured reservoir compartmentalization, block size, and tributary volume analysis; development and demonstration of fractured reservoir discrete feature data analysis tools; development of tools for data integration and reservoir simulation through application of discrete feature network technologies for tertiary oil production; quantitative evaluation of the economic value of this analysis approach.
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