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Title: Further Development and Application of GEOFRAC-FLOW to a Geothermal Reservoir

Abstract

GEOFRAC is a three-dimensional, geology-based, geometric-mechanical, hierarchical, stochastic model of natural rock fracture systems. The main characteristics of GEOFRAC are its use of statistical input representing fracture patterns in the field in form of the fracture intensity P32 (fracture area per volume) and the best estimate fracture size E(A). This information can be obtained from boreholes or scanlines on the surface, on the one hand, and from window sampling of fracture traces on the other hand. In the context of this project, “Recovery Act - Decision Aids for Geothermal Systems”, GEOFRAC was further developed into GEOFRAC-FLOW as has been reported in the reports, “Decision Aids for Geothermal Systems - Fracture Pattern Modelling” and “Decision Aids for Geothermal Systems - Fracture Flow Modeling”. GEOFRAC-FLOW allows one to determine preferred, interconnected fracture paths and the flow through them.

Authors:
 [1];  [1]
  1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
Publication Date:
Research Org.:
Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Geothermal Technologies Office (EE-4G)
OSTI Identifier:
1236455
Report Number(s):
DE-EE0002743
DOE Contract Number:
EE0002743
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
15 GEOTHERMAL ENERGY; 3D; modeling; stochastic; mechanical; hierarchical; Recovery Act

Citation Formats

Einstein, Herbert, and Vecchiarelli, Alessandra. Further Development and Application of GEOFRAC-FLOW to a Geothermal Reservoir. United States: N. p., 2014. Web. doi:10.2172/1236455.
Einstein, Herbert, & Vecchiarelli, Alessandra. Further Development and Application of GEOFRAC-FLOW to a Geothermal Reservoir. United States. doi:10.2172/1236455.
Einstein, Herbert, and Vecchiarelli, Alessandra. 2014. "Further Development and Application of GEOFRAC-FLOW to a Geothermal Reservoir". United States. doi:10.2172/1236455. https://www.osti.gov/servlets/purl/1236455.
@article{osti_1236455,
title = {Further Development and Application of GEOFRAC-FLOW to a Geothermal Reservoir},
author = {Einstein, Herbert and Vecchiarelli, Alessandra},
abstractNote = {GEOFRAC is a three-dimensional, geology-based, geometric-mechanical, hierarchical, stochastic model of natural rock fracture systems. The main characteristics of GEOFRAC are its use of statistical input representing fracture patterns in the field in form of the fracture intensity P32 (fracture area per volume) and the best estimate fracture size E(A). This information can be obtained from boreholes or scanlines on the surface, on the one hand, and from window sampling of fracture traces on the other hand. In the context of this project, “Recovery Act - Decision Aids for Geothermal Systems”, GEOFRAC was further developed into GEOFRAC-FLOW as has been reported in the reports, “Decision Aids for Geothermal Systems - Fracture Pattern Modelling” and “Decision Aids for Geothermal Systems - Fracture Flow Modeling”. GEOFRAC-FLOW allows one to determine preferred, interconnected fracture paths and the flow through them.},
doi = {10.2172/1236455},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2014,
month = 5
}

Technical Report:

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  • This paper describes the first known explosive stimulation successfully conducted in a geothermal well. Two tests were performed in a 2690-meter-(8826-ft.) deep Union Oil well at the Geysers field in Northern California in December 1981. The heat-resistant process, called GEOFRAC, uses a new unique, explosive HITEX 2, which is a nondetonable solid at room temperature. Upon melting at a temperature of 177[degrees]C (350[degrees]F), the HITEX 2 liquid becomes an explosive that can be safely heated to temperatures greater than 260[degrees]C (500[degrees]F). These unique properties of the explosive were exploited in the GEOFRAC process through the cooperative efforts of Physics Internationalmore » Company (PI), Rocket Research Company (RRC), Union oil Company (UO), and the university of California Los Alamos National Laboratories (LANL).« less
  • This paper describes the first known explosive stimulation successfully conducted in a geothermal well. Two tests were performed in a 2690-meter-(8826-ft.) deep Union Oil well at the Geysers field in Northern California in December 1981. The heat-resistant process, called GEOFRAC, uses a new unique, explosive HITEX 2, which is a nondetonable solid at room temperature. Upon melting at a temperature of 177{degrees}C (350{degrees}F), the HITEX 2 liquid becomes an explosive that can be safely heated to temperatures greater than 260{degrees}C (500{degrees}F). These unique properties of the explosive were exploited in the GEOFRAC process through the cooperative efforts of Physics Internationalmore » Company (PI), Rocket Research Company (RRC), Union oil Company (UO), and the university of California Los Alamos National Laboratories (LANL).« less
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