Preliminary Geothermal Favorability Map of the Great Basin
Table of Contents
IDENTIFICATION_INFORMATION
Citation:
Citation_Information:
Originator: Mark Coolbaugh
Originator: Richard Zehner
Originator: Corne Kreemer
Originator: David Blackwell
Originator: Gary Oppliger
Originator: Don Sawatzky
Originator: Geoff Blewitt
Originator: Aasha Pancha
Originator: Maria Richards
Originator: Catie Helm-Clark
Originator: Lisa Shevenell
Originator: Gary Raines
Originator: Gary Johnson
Originator: Tim Minor
Originator: Tonya Boyd
Publication_Date: 20050505
Title: Preliminary Geothermal Favorability Map of the Great Basin
Edition:
Geospatial_Data_Presentation_Form: Map
Publication_Information:
Publication_Place: Reno, Nevada
Publisher: Great Basin Center for Geothermal Energy
Other_Citation_Details:
Blackett, R.E. and Wakefield, S.I., 2002, Geothermal
resources of Utah, a digital atlas of Utah's geothermal
resources: Utah Geological Survey Open-File Report 397,
CD-ROM.
Blackwell, D.D. and Richards, M., 2004, Geothermal Map of
North America, AAPG, map item number 423, scale
1:6,500,000.
Coolbaugh, M.F. and Shevenell, L.A., 2004, A method for
estimating undiscovered geothermal resources in Nevada and
the Great Basin: Geothermal Resources Council Transactions,
v. 28, p. 13-18.
Higgins, C.T. and Martin, R.C., 1980, Geothermal resources
of California: California Geologic Data Map Series Map No.
4
Mariner, R.H., Presser, T.S., and Evans, W.C., 1983,
Geochemistry of active geothermal systems in the northern
Basin and Range province: Geothermal Resources Council,
Special Report No. 13, p. 95-119.
Mitchell, J.C., Johnson, L.L., and Anderson, J.E., 1980,
Geothermal investigations in Idaho, Part 9, Potential for
direct heat application of geothermal resources: Idaho
Department of Water Resources Water Information Bulletin
No. 30.
Peterson, N.V., Priest, G.R., Black, G.L., Brown, D.E., and
Woller, N.M., 1982, Geothermal resources of Oregon: Oregon
Department of Geology and Mineral Industries.
Prudic, D.E., Harrill, J.R., and Burbey, T.J., 1995,
Conceptual evaluation of regional groundwater flow in the
carbonate-rock province of the Great Basin, Nevada, Utah,
and adjacent states: U.S. Geological Survey Professional
Paper 1409-D, 102 pp.
Raines, G.L., Sawatzky, D.L., and Connor, K.A., Great Basin
Geoscience Data Base: USGS Digital Data Series DDS-041.
Shevenell,
L., Garside, L.J. and Hess, R.H., 2000, Nevada Geothermal
Resources: Nevada Bureau of Mines and Geology, Map 126.
Trexler, D. T., Flynn, T., Koenig, B. A., and Ghusn, G.
Jr., 1983, Geothermal resources of Nevada: Map produced by
the National Geophysical Data Center, National Oceanic and
Atmospheric Administration for the Geothermal and
Hydropower Technologies Division, U.S. Department of
Energy, 1 map.
Witcher, J.C., Stone, C., and Hahman, W.R., 1982,
Geothermal Resources of Arizona: Arizona Bureau of Geology
and Mineral Technology, University of Arizona, Tucson, AZ.
Online_Linkage: HTTP://www.unr.edu/Geothermal/
Larger_Work_Citation:
Citation_Information:
Originator:
Publication_Date:
Title:
Publication_Information:
Publication_Place:
Publisher:
Online_Linkage:
Description:
Abstract:
This ESRI real number GRID provides information for
assessing regional geothermal potential in the Great Basin.
The values provide a ranking of favorability for
high-temperature (> 150°C) extensional- type geothermal
systems. The favorability calculation is based on a
logistic regression posterior probability statistic, with
the GRID value being proportional to the log-transformed
(posterior logit) logistic regression posterior
probability. A total of 51 geothermal systems were used as
training sites for weights-of-evidence and logistic
regression spatial statistics. These 51 geothermal systems
are either producing electrical power today or have
geothermometer temperatures ? 150°C.
Purpose:
This ESRI floating point GRID was developed for a weights
of evidence/logistic regression analysis of geothermal
potential of the Great Basin (Coolbaugh and others, 2005).
Supplemental_Information:
Potential Influence of Aquifers: Most known high-temperature geothermal
systems in the Great Basin (? 150°C) occur outside regional groundwater aquifers
(Fig. 1), including the Snake River Plain and Northwest Basalt aquifers in the
northern Great Basin (USGS Principal Aquifers of the US
HTTP://nationalatlas.gov/aquifersm.html) and the carbonate
aquifer in eastern Nevada and western Utah (Prudic et al.,
1995). It is hypothesized that lateral groundwater flow
could be capturing and entraining rising thermal fluids in
these aquifers, and suppressing the formation of hot
springs, thereby rendering those areas less completely
explored for geothermal systems than elsewhere in the Great
Basin. In
order to minimize a potential bias with regard to aquifers
in the favorability model, the geological and geophysical
maps used as evidence were selected for their ability to
model the geothermal potential independent of the presence
of those aquifers (at least at economic depths). As a first
step, weights-of-evidence and logistic regression model
weights for each evidence map were calculated for the
non-aquifer areas (Figure 1). Those weights were then used
to extrapolate geothermal favorability beneath areas having
overlying regional aquifers. The logistic regression model
accurately predicted 33 known geothermal training sites in
non-aquifer regions, but predicted 24 training sites in the
aquifer areas, whereas only 18 are known. This suggests
that the regional aquifers may be under-explored relative
to non-aquifer areas. It
is important to note that this model is not designed to
predict undiscovered geothermal systems. The model is meant
to predict the relative geothermal favorability within the
Great Basin, and significant numbers of undiscovered
geothermal systems are likely to occur in both the aquifer
and non-aquifer regions (Coolbaugh and Shevenell, 2004).
MODEL LAYERS:
Six geological/geophysical maps were combined into four
evidence layers and were used to model geothermal
favorability. A description of each of these four layers
follows:
1) Combined Gravity/Topographic Gradient Map (Gary
Oppliger; Arthur Brant Laboratory for Exploration
Geophysics, University of Nevada, Reno): As a proxy for
measuring the effective vertical displacement on late
Tertiary and Quaternary faults in the Great Basin, a
residual gravity map was combined with a topographic
digital elevation model (DEM), and then the total surface
slope (horizontal gradient) was calculated. The residual
gravity map, a 20-km upward continued residual isostatic
gravity anomaly Lisa: remove preceding phrase between the
commas, was further reduced by removing bedrock-only
regional gravity trends to produce a basins-only gravity
anomaly map. This gravity map was converted to an
approximate equivalent amount of subsurface basement relief
using 60 meters/mgal (equivalent to a density contrast of
0.4 g/cm3), and then added to the 1-km DEM. The combined
bedrock surface slope was then calculated by computing the
total horizontal gradient for each 1-km cell. Lisa: site
reference
2) Combined Global Positioning System (GPS) and Fault
Dilation Map (Corné Kreemer, Geoff Blewitt; Nevada Geodetic
Laboratory): Crustal dilation rates derived from GPS
velocity measurements (interseismic strain) were added to
dilation rates calculated from Quaternary fault slip rate
data (long-term seismic strain) to produce a more
geographically complete estimate of crustal dilation in the
Great Basin. The geodetic strain rates were based on 476
GPS velocity measurements located throughout and just
outside the Great Basin. These velocities were compiled
from multiple networks, including the BARGEN continuous network, multiple
USGS campaign networks, and several other groups. Velocities affected by known
magmatic/volcanic activity were excluded. A Quaternary faults database, obtained
from the USGS Quaternary Fault and Fold Database
HTTP://gldims.cr.usgs.gov/qfault/viewer.htm)
was updated with more recent slip rate estimates compiled in 1996 and 2002
HTTP://eqhazmaps.usgs.gov/html/faults2002.html).
Slip rate parameters were converted to long-term strain rate
tensors, from which dilation was calculated for every 20 km
square grid cell in the Great Basin.
3) Temperature Gradient Map (David Blackwell, Maria
Richards; Southern Methodist University (SMU) Geothermal Laboratory):
A shallow crustal
(0-1 km) temperature gradient map was generated using the SMU geothermal well
database, which includes wells compiled by SMU (http://www.smu.edu/geothermal/),
the USGS (Sass et al., 1999;
http://wrgis.wr.usgs.gov/open-file/of99-425/webmaps/home.html), and other
sources. Temperature gradients were derived in a multi-step process beginning
with calculation of heat flux at individual wells, interpolation of heat flux
between wells to produce heat flux maps (e.g., Blackwell and Richards, 2004),
and conversion of the heat flux map to a temperature gradient map using thermal
conductivities assigned for grouped geological formations. Improvements in the
spatial resolution of the gradient map in the Great Basin were obtained by
assigning separate thermal conductivities to graben-filled Quaternary sediments,
basement rocks in horst blocks, and regions of late Tertiary and Quaternary
volcanic rocks. Purposely excluded from the calculations used to make this map
were geothermal wells and other wells drilled in known geothermal areas, so that
the predicted temperature gradients would be independent of the degree of
geothermal exploration
4) Seismicity Map (Aasha Pancha; Nevada Seismological Laboratory):
The seismicity map
was generated by adding up all historical earthquake magnitudes within a 40 km
radius of each grid cell in the model. The distance from the epicenter to the
center of each cell was used to inversely weight individual earthquake
magnitudes. To avoid a bias in the detection of earthquakes near seismograph
stations, earthquakes were not included in the seismicity calculation unless
they were strong enough to be detected anywhere in the Great Basin. Earthquakes
with a magnitude of
³4.8 were
considered strong enough to meet this criterion regardless of the year of
occurrence, and Pancha et al. (in review) compiled these earthquakes from
multiple catalogs. Due to improvements in the seismograph network that occurred
around 1970, all earthquakes with a magnitude of 4.0 and greater that occurred
during or after 1970 were considered detectable regardless of their epicenter
location, and were added to this compilation. These lower-magnitude earthquakes
came from two main catalog sources: the USGS National Earthquake Information
Center and the Berkeley Advanced National Seismic System. Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date:
Ending_Date:
Currentness_Reference:
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -36.6409
East_Bounding_Coordinate: 38.0474
North_Bounding_Coordinate: 52.8136
South_Bounding_Coordinate: 19.7292
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Dilational Strain
Theme_Keyword: Quaternary Faults
Theme_Keyword: GPS
Theme_Keyword: Geodesy
Theme_Keyword: Strain Tensors
Theme_Keyword: Weights of Evidence
Theme_Keyword: Logistic Regression
Theme_Keyword: Temperature Gradient
Theme_Keyword: Gravity Gradient
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: Arizona
Place_Keyword: California
Place_Keyword: Great Basin
Place_Keyword: Idaho
Place_Keyword: Nevada
Place_Keyword: North America
Place_Keyword: Oregon
Place_Keyword: Utah
Place_Keyword: Western United States
Place_Keyword: Wyoming
Access_Constraints:
None
Use_Constraints:
This spatial information was derived from a variety of
sources. Care was taken in the creation of these themes,
but they are provided "as is". The Great Basin Center for
Geothermal Energy, the University of Nevada, Reno or any of
the data providers cannot accept any responsibility for
errors, omissions, or positional accuracy in the digital
data or underlying records. There are no warranties,
expressed or implied, accompanying this data set.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Great Basin Center for Geothermal Energy
Contact_Person: Richard Zehner
Contact_Position: Research Scientist, Assistant GIS Specialist
Contact_Address:
Address_Type: mailing and physical address
Address: MS 172, University of Nevada Reno
City: Reno
State_or_Province: NV
Postal_Code: 89557
Country: USA
Contact_Voice_Telephone: 775-784-7055
Contact_Facsimile_Telephone: 775-327-5801
Contact_Electronic_Mail_Address: zehner@unr.edu
Hours_of_Service: M-F 8-5
Native_Data_Set_Environment:
ESRI Grid format
Top
DATA_QUALITY_INFORMATION
Attribute_Accuracy:
Attribute_Accuracy_Report:
See references for each evidence layer comprising this GRID
Logical_Consistency_Report:
Completeness_Report:
Should be complete
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Unknown
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
Unknown
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator:
Publication_Date:
Title:
Edition:
Geospatial_Data_Presentation_Form: map
Publication_Information:
Publication_Place:
Publisher:
Other_Citation_Details:
REFERENCES:
Blackett, R.E. and Wakefield, S.I., 2002, Geothermal
resources of Utah, a digital atlas of Utah's geothermal
resources: Utah Geological Survey Open-File Report 397,
CD-ROM.
Blackwell, D.D. and Richards, M., 2004, Geothermal Map of
North America, AAPG, map item number 423, scale
1:6,500,000.
Coolbaugh, M.F. and Shevenell, L.A., 2004, A method for
estimating undiscovered geothermal resources in Nevada and
the Great Basin: Geothermal Resources Council Transactions,
v. 28, p. 13-18.
Higgins, C.T. and Martin, R.C., 1980, Geothermal resources
of California: California Geologic Data Map Series Map No.
4
Mariner, R.H., Presser, T.S., and Evans, W.C., 1983,
Geochemistry of active geothermal systems in the northern
Basin and Range province: Geothermal Resources Council,
Special Report No. 13, p. 95-119.
Mitchell, J.C., Johnson, L.L., and Anderson, J.E., 1980,
Geothermal investigations in Idaho, Part 9, Potential for
direct heat application of geothermal resources: Idaho
Department of Water Resources Water Information Bulletin
No. 30.
Peterson, N.V., Priest, G.R., Black, G.L., Brown, D.E., and
Woller, N.M., 1982, Geothermal resources of Oregon: Oregon
Department of Geology and Mineral Industries.
Prudic, D.E., Harrill, J.R., and Burbey, T.J., 1995,
Conceptual evaluation of regional groundwater flow in the
carbonate-rock province of the Great Basin, Nevada, Utah,
and adjacent states: U.S. Geological Survey Professional
Paper 1409-D, 102 pp.
Raines, G.L., Sawatzky, D.L., and Connor, K.A., Great Basin
Geoscience Data Base: USGS Digital Data Series DDS-041.
Shevenell,
L., Garside, L.J. and Hess, R.H., 2000, Nevada Geothermal
Resources: Nevada Bureau of Mines and Geology, Map 126.
Trexler, D. T., Flynn, T., Koenig, B. A., and Ghusn, G.
Jr., 1983, Geothermal resources of Nevada: Map produced by
the National Geophysical Data Center, National Oceanic and
Atmospheric Administration for the Geothermal and
Hydropower Technologies Division, U.S. Department of
Energy, 1 map.
Witcher, J.C., Stone, C., and Hahman, W.R., 1982,
Geothermal Resources of Arizona: Arizona Bureau of Geology
and Mineral Technology, University of Arizona, Tucson, AZ.
Online_Linkage:
Larger_Work_Citation:
Citation_Information:
Originator:
Publication_Date:
Title:
Publication_Information:
Publication_Place:
Publisher:
Online_Linkage:
Source_Scale_Denominator:
Type_of_Source_Media:
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date:
Ending_Date:
Source_Currentness_Reference:
Source_Citation_Abbreviation:
Source_Contribution:
Process_Step:
Process_Description:
See above and Coolbaugh and others (2005)
Source_Used_Citation_Abbreviation:
Process_Date:
Source_Produced_Citation_Abbreviation:
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Organization: Great Basin Center for Geothermal Energy
Contact_Person: Richard Zehner
Contact_Position: Research Scientist, Assistant GIS Specialist
Contact_Address:
Address_Type: mailing and physical address
Address: MS 172, University of Nevada Reno
City: Reno
State_or_Province: NV
Postal_Code: 89557
Country: USA
Contact_Voice_Telephone: 775-784-7055
Contact_Facsimile_Telephone: 775-327-5801
Contact_Electronic_Mail_Address: zehner@unr.edu
Hours_of_Service: M-F 8-5
Top
SPATIAL_DATA_ORGANIZATION_INFORMATION
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Grid Cell
Row_Count: 3873
Column_Count: 5040
Top
SPATIAL_REFERENCE_INFORMATION
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: Lambert Conformal Conic
Lambert_Conformal_Conic:
Standard_Parallel: 33.000000
Standard_Parallel: 45.000000
Longitude_of_Central_Meridian: 0.000000
Latitude_of_Projection_Origin: 0.000000
False_Easting: 0.000000
False_Northing: 0.000000
Standard_Parallel: 33.000000
Standard_Parallel: 45.000000
Longitude_of_Central_Meridian: 0.000000
Latitude_of_Projection_Origin: 0.000000
False_Easting: 0.000000
False_Northing: 0.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: Row and column
Coordinate_Representation:
Abscissa_Resolution:
Ordinate_Resolution:
Planar_Distance_Units: Meters
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1927
Ellipsoid_Name: Clarke 1866
Semi-major_Axis: 6378206.4000000
Denominator_of_Flattening_Ratio: 294.98
Top
ENTITY_AND_ATTRIBUTE_INFORMATION
Overview_Description:
Entity_and_Attribute_Overview:
This real number ESRI GRID file contains probability values
measured in log probability.
Entity_and_Attribute_Detail_Citation:
Top
DISTRIBUTION_INFORMATION
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Great Basin Center for Geothermal Energy
Contact_Person: Richard Zehner
Contact_Position: Research Scientist, Assistant GIS Specialist
Contact_Address:
Address_Type: mailing and physical address
Address: MS 172, University of Nevada Reno
City: Reno
State_or_Province: NV
Postal_Code: 89557
Country: USA
Contact_Voice_Telephone: 775-784-7055
Contact_Facsimile_Telephone: 775-327-5801
Contact_Electronic_Mail_Address: zehner@unr.edu
Hours_of_Service: M-F 8-5
Resource_Description:
Distribution_Liability:
This spatial information was derived from a variety of
sources. Care was taken in
the creation of these themes, but they are provided "as
is". The Great Basin Center
for Geothermal Energy, the University of Nevada, Reno or
any of the data providers
cannot accept any responsibility for errors, omissions, or
positional accuracy
in the digital data or underlying records. There are no
warranties, expressed
or implied, accompanying this data set.
Top
METADATA_REFERENCE_INFORMATION
Metadata_Date: 20050505
Metadata_Review_Date:
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Great Basin Center for Geothermal Energy
Contact_Person: Richard Zehner
Contact_Position: Research Scientist, Assistant GIS Specialist
Contact_Address:
Address_Type: Mailing and physical address
Address: MS 172, University of Nevada Reno
City: Reno
State_or_Province: NV
Postal_Code: 89557
Country: USA
Contact_Voice_Telephone: 775-784-7055
Contact_Facsimile_Telephone: 775-327-5801
Contact_Electronic_Mail_Address: zehner@unr.edu
Hours_of_Service: M-F 8-5
Metadata_Standard_Name: FGDC CSDGM
Metadata_Standard_Version: FGDC-STD-001-1998
Top