Renewable Energy Resources on Mining Lands Geothermal Mapping by

							 Renewable Energy Resources on
   Mining Lands: Geothermal
Mapping by the Great Basin Center
     for Geothermal Energy




      Lisa Shevenell, Ben Delwiche, and
                Scott Phillips
           Mackay School of Mines
         University of Nevada, Reno

     Mining Energy Solutions Conference
              August 27, 2003
           Purpose

• To present a series of maps
  showing geothermal anomalies
  in Nevada and their locations
  relative to active and inactive,
  precious metal mines.
• To encourage local geothermal
  assessment efforts at mines that
  could either use the resource to
  produce power or for direct use
  applications either while in
  operation or after closure.
           Geothermal Resources of Nevada


      Geothermal Resources of Nevada




From Shevenell &
   From
          2003, &
Garside,ShevenellNBMG
   Garside, 2003, NBMG Map
Map 141
   141
Chalcedony Geothermometer
Chalcedony Geothermometer and
       Sample Locations
Na-K-Ca Geothermometer
Estimated Interseismic Strain Rate
Perpendicular to Quaternary Faults
        (Blewitt, et al., 2002)


 Calculated regional strain rate
 field, including all strain matrix
 components, from all available
 GPS stations in the Great Basin
 (and beyond).
                             Strain Rate




(from Geoff Blewitt, 2003)
     The Density Function Model
            (Coolbaugh)

• Regional favorability map for high-
  temperature geothermal systems using
  statistically-derived weights for the
  following types of map information:

•   Young volcanic rocks
•   Depth to the water table
•   Regional heat flux
•   Presence of Paleozoic carbonate rocks
•   Northeast-trending young faults
•   Concentrations of boron in groundwaters
•   Earthquake Richter magnitude sums
                    Density Function Model




(from Mark Coolbaugh, 2003)
    Logistic Regression
    Model Components
       (Coolbaugh)

Evidence Layers Used to build
 this model include:

• Young Volcanics
• Young Faults
• Strain Rate
• Gravity
• Earthquakes
Predicts favorability where hot
  springs may not be present
Logistics Regression Model
     Anomalies & Contoured
Geothermometer Temperatures (ºC)
           Mine           # anomalies   Chalced Na-K-Ca

Florida Canyon Mine
   (point)                    2          205      229

Mule Canyon                   4          108      128

Pyramid Mine                  2          102      107

Hycroft Mine                  1          101      89

Rosebud Mine                  1           94      93

Denton-Rawhide Mine           3           91      93

Marigold                      1           81      90

Lone Tree Mine                3           76      81


Battle Mountain Complex       4           75      121

McCoy/Cove Mine               4           73      76
      Anomalies & Contoured
    Geothermometer Temperatures

          Mine           # anomalies   Chalced   Na-K-Ca

Gold Eagle Mine              2           72        67

Cortez Gold Mine             2           70        33

Pinson Mine                  1           68        85

MacArthur Mine               2           67        49

Sterling Mine                1           63        64

Yerington Mine               4           60        48

Coeur Rochester Mine         3           54        43

Willow Creek Mine            4           46        57

Lucerne Mine                 2           39        31

Haywood Leach Facility       3           36        28
              Conclusions

 Mule Canyon has relatively high potential;
    several others may also warrant closer
    inspection
 Only site that has data in the current models
    is Florida Canyon, and maps show high
    potential for that area, as they should
 Carlin Trend mines appear to be in area of
     lower geothermal potential, although T
     up to 63ºC are known (Meikle). Some
     data added from mines, but no significant
     changes observed in T contours.
 Additional data need to be incorporated into
    models (e.g., Rawhide and Meikle have
    elevated temperatures)