GRED III Geothermal Exploration Project

Chena Hot Springs and the Department of Energy are jointly funding a $1.4 million exploration project designed to locate and characterize the geothermal resource underlying Chena Hot Springs.  The goal is to build a model of the deep reservoir using geologic and geophysical exploration techniques coupled with state of the art reservoir engineering.  Once the model has been completed, it will be tested by drilling a 4000ft slim hole, sited to intersect the deep geothermal reservoir.  We hope to drill this test hole in 2008, depending on funding from the Department of Energy.  The Geothermal budget was zeroed out in 2007, and this has effected our completion of this project.  Partners in this project include:

To download a copy of the Phase I Report click here.

Reservoir Engineering

  

 Geology

Gradient Hole Temperature Survey

 Modern pressure transient analysis software will be used to interpret interference and pressure transient tests between existing wells which penetrating the shallow reservoir in order to find the up flow zone, and pinpoint the location of the deep reservoir in relation to the shallow system  

  Granite plutons to the North of Chena

 A detailed mapping program of the Chena Hot Springs area will be conducted, including sampling and chemical analysis of rocks and well cuttings.  A database of local fault and fracture features will also be assembled to give a more complete picture of the geologic constraints on the geothermal system.
Heat Flow Survey   Water Chemistry and Hydrology

     Heat flow map of the State of Alaska, created by SMU

A study of the local heat flow will be conducted by drilling and instrumenting several gradient holes to define the extent of the geothermal system and better understand the local thermal regime.

 

  

  Kenji Yoshikawa from the University of Alaska

 Local thermal and meteoric water at Chena will be analyzed, and contrasted with the local hydrology to create a mixing model and delineate the regional extent of the geothermal system, the temperatures that can be expected at depth, and the age of the geothermal water.
FLIR Survey   CSAMT and NSAMT Surveys
  FLIR image of the main hot springs area at Chena

 

 FLIR (Forward Looking Infrared Radiometry) airborne imaging techniques will be used to build a high resolution temperature map of the Chena Hot Springs area.  

Line 3 from MT survey which traverses the main hot springs area

 Zonge Engineering has conducted an extensive natural source (NSAMT) and controlled source (CSAMT) survey of the Monument Creek Valley where Chena Hot Springs is located.  
Airborne Geophysical Surveys    

Current geologic map of the Chena Hot Springs area

 Fugro Airborne Surveys will fly airborne electromagnetics, magnetics and radiometrics for the area immediately surrounding Chena Hot Springs in order to map localized faults and fractures which may control and constrain the geothermal system