Finding Large Aperture Fractures in Geothermal Resource Areas Using a Three-Component Long-Offset Surface Seismic Survey Geothermal Project

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Last modified on July 22, 2011.

Project Title Finding Large Aperture Fractures in Geothermal Resource Areas Using a Three-Component Long-Offset Surface Seismic Survey
Project Type / Topic 1 Recovery Act: Geothermal Technologies Program
Project Type / Topic 2 Validation of Innovative Exploration Technologies
Project Description Because fractures and faults with sub-commercial permeability can propagate hot fluid and hydrothermal alteration throughout a geothermal reservoir, potential field geophysical methods including resistivity, gravity, heatflow and magnetics cannot distinguish between low-permeability fractures and LAF’s (Large Aperature Fractures). USG will develop and test the combination of three-component,long-offset seismic surveying, permanent scatter synthetic aperture radar interferometry (PSInSAR) and structural kinematic analysis as an integrated method for locating and 3-D mapping of LAF’s in shallow to intermediate depth (600-4000 feet) geothermal systems. This project is designed to test the methodology on known occurrences of LAF’s and then apply the technology to expand an existing production field and find a new production field in a separate but related resource area. A full diameter production well will be drilled into each of the two lease blocks covered by the geophysical exploration program.
State Nevada
Objectives Develop an exploration strategy and suite of innovative geophysical techniques that will precisely locate Large Aperature Fractures distributed within a faulted and fractured geothermal system
Awardees (Company / Institution) US Geothermal, Inc.

Funding Opportunity Announcement DE-FOA-0000109
DOE Funding Level (total award amount) $3,772,560.00
Awardee Cost Share $3,451,878.00
Total Project Cost $7,224,438.00

Principal Investigator(s) William Teplow, R.G., VP Exploration, U.S. Geothermal Inc.

Targets / Milestones -Significantly reduced number of dry holes, fewer wells drilled and higher per-well productivity for a given wellfield power output

-Significantly reduce parasitic loads for production well pumping -Increased production at San Emidio in the southern wellfield and a new power plant in the northern exploration block is expected to yield a total net power output of approximately 20 MW -Produce 175 million kw-hr annually of emissions-free baseload energy displacing 350,000 tons of CO2 yearly from equivalent coal-fired generation

Location of Project San Emidio, NV
About the Area The San Emidio geothermal resource area, which is under lease to USG contains four exploration and production wells that have encountered and currently produce from LAF’s in the southern half of the resource area. USG also has a lease block containing the northern extension of the San Emidio geothermal resource located 2 miles to the north of the operating wellfield. The northern lease block is thermally active but unexplored by deep drilling. This block constitutes the exploration test area for the methodology developed in the southern block containing the known LAF’s. Success of this program in the southern SE lease block will result in expansion of the current field capacity from 4 MW to 16MW. Success in the northern lease block will result in development of a separate geothermal power generation


Impacts Demonstration that the methodology utilizing advanced seismic can be effectively used to find large apertures and good flow rates with potential broad application.
Funding Source American Recovery and Reinvestment Act of 2009
References EERE Geothermal Technologies Programs[1]


  1. EERE Geothermal Technologies Programs