Isotopic Analysis- Fluid

GEOTHERMAL ENERGY

Exploration Technique: Isotopic Analysis- Fluid

Details

Activities (79)

Areas (37)

Regions (6)

NEPA(0)

[edit]

"{{{ExplorationCostPerMetric}}}" is not in the list (100 feet cut, 30 foot core, compound, day, element, foot, hour, mile, point, process, ...) of allowed values for the "ExplorationCostPerMetric" property."{{{ExplorationTimePerMetric}}}" is not in the list (job, 10 mile, 10 stn, 100 mile, sq. mile, foot) of allowed values for the "ExplorationTimePerMetric" property.

Exploration Technique Information
Exploration Group:	Lab Analysis Techniques
Exploration Sub Group:	Fluid Lab Analysis
Parent Exploration Technique:	Fluid Lab Analysis
Information Provided by Technique
Lithology:	Water rock interaction
Stratigraphic/Structural:
Hydrological:	Origin of hydrothermal fluids; Mixing of hydrothermal fluids
Thermal:	Isotopic ratios can be used to characterize and locate subsurface thermal anomalies.

Isotopic Analysis- Fluid:

Isotopes are atoms of the same element that have different numbers of neutrons. An isotopic analysis looks at a particular isotopic element(s) in a given system, while the conditions which increase/decrease the number of neutrons are well understood and measurable. Fluid isotopes are used to characterize a fluids origin, age, and/or interaction with rocks or other fluids based on unique isotopic ratios or concentrations.

Other definitions:Wikipedia Reegle

Introduction

Property "IntroText" (as page type) with input value "File:nuplasma_MC-ICPMS.jpg|thumb|270px|left|Photo of a Nu plasma Multicollector ICP-MS system used for isotopic analysis. Photo from Vervoot & Mueller (2012).'"`UNIQ--ref-00000001-QINU`"'Using "ReferenceForhttp://serc.carleton.edu/research_education/geochemsheets/techniques/MCICPMS.html" as property chain is not permitted during the annotation process.]]</br></br>Isotope analysis is typically conducted by hydrologists, biologists, and geochemists. There are many different isotopes, but they all generally fall into two categories; radioactive or stable. Radioactive isotopes have known decay rates and half-lives, which are very useful for dating particular fluids or materials. Stable isotopes do not decay and are used to measure the ratios of the heavy isotope vs light isotope to reveal general conditions that would lead to this heavy/light isotope ratio. For example, oxygen isotopes have been used to understand paleoclimates by measuring the heavy oxygen (18O) vs light oxygen (16O) ratio. Knowing that the heavy isotope will be more difficult to evaporate from a body of water, it is possible to deduce the climate; high 18O will indicate a warmer climate because of a higher 18O:16O ratio. There are many applications of isotope geochemistry, some which have been utilized for geothermal exploration techniques. Isotopic analysis is useful as a geothermal exploration technique because it reveals information about the source of fluid and heat, age of fluids, and the overall spatial circulation of hydrothermal waters." contains invalid characters or is incomplete and therefore can cause unexpected results during a query or annotation process.

Photo of a Nu plasma Multicollector ICP-MS system used for isotopic analysis. Photo from Vervoot & Mueller (2012).Using "ReferenceForhttp://serc.carleton.edu/research_education/geochemsheets/techniques/MCICPMS.html" as property chain is not permitted during the annotation process.

Isotope analysis is typically conducted by hydrologists, biologists, and geochemists. There are many different isotopes, but they all generally fall into two categories; radioactive or stable. Radioactive isotopes have known decay rates and half-lives, which are very useful for dating particular fluids or materials. Stable isotopes do not decay and are used to measure the ratios of the heavy isotope vs light isotope to reveal general conditions that would lead to this heavy/light isotope ratio. For example, oxygen isotopes have been used to understand paleoclimates by measuring the heavy oxygen (18O) vs light oxygen (16O) ratio. Knowing that the heavy isotope will be more difficult to evaporate from a body of water, it is possible to deduce the climate; high 18O will indicate a warmer climate because of a higher 18O:16O ratio. There are many applications of isotope geochemistry, some which have been utilized for geothermal exploration techniques. Isotopic analysis is useful as a geothermal exploration technique because it reveals information about the source of fluid and heat, age of fluids, and the overall spatial circulation of hydrothermal waters.

Use in Geothermal Exploration

Property "GeoUse" (as page type) with input value "The hydrothermal fluids circulating in a geothermal system have a unique signature that can be used to determine where that water came from, how old it is, whether it has mixed with other fluids, and which direction it is moving in. Various isotopic analyses provide certain information, for example, noble gases (He, Ne, Ar, Kr, and Xe) are good tracers for heat and fluid sources, origins, and reservoir properties. Fractionating elements (H, C, O, and N) are useful for identifying recharge, water/rock ratios, and chemical equilibrium temperatures.'"`UNIQ--ref-00000003-QINU`"' Radioactive isotopes of certain elements (3H, 36Cl) encountered in groundwater may also be used to directly date waters from a geothermal reservoir. Isotopes can be measured in gas, water, or rocks samples, and their characteristics are used to identify important information regarding a hydrothermal system. Specific properties of the various isotopes used in geothermal exploration are discussed in the Physical Properties section of this page (below).</br></br>Analysis of 36Cl- isotopes and interpretation of 36Cl/Cl ratios of waters sampled from springs and drill holes in the Valles Caldera region indicated that deeply circulating meteoric waters derive their high chloride contents from Precambrian basement and Paleozoic rocks before ascending into more shallow volcaniclastic reservoirs, and that residence times for these waters are 50 years old, and that the hydrothermal system is recharged by slow percolation of rainwater through fractures in and around the caldera’s resurgent dome.</br></br>Williams and McKibben (1989) used oxygen isotope ratios to characterize geothermal fluids from the Salton Sea Geothermal System, California.'"`UNIQ--ref-00000008-QINU`"' Results showed that the higher temperature reservoir fluids had higher concentrations of 18O than the cooler fluids, and the relatively homogenous source fluids entering the system underwent a high degree of water-rock interaction.'"`UNIQ--ref-0000000A-QINU`"'</br></br>Kennedy & Van Soest (2007) were able to correlate high 3He concentrations from surface waters with active crustal deformation.'"`UNIQ--ref-0000000C-QINU`"' These results enabled the identification of mantle-derived fluids at the surface, and are indicative of areas with high levels of crustal permeability or magmatic activity. At the Long Valley Caldera, CA, rising helium isotope ratios in fumaroles at Mammoth Mountain were also correlated with increased seismic activity in 1989, suggesting that recent magmatic intrusions contribute to the heat input of the present hydrothermal system.'"`UNIQ--ref-0000000D-QINU`"'" contains invalid characters or is incomplete and therefore can cause unexpected results during a query or annotation process. The hydrothermal fluids circulating in a geothermal system have a unique signature that can be used to determine where that water came from, how old it is, whether it has mixed with other fluids, and which direction it is moving in. Various isotopic analyses provide certain information, for example, noble gases (He, Ne, Ar, Kr, and Xe) are good tracers for heat and fluid sources, origins, and reservoir properties. Fractionating elements (H, C, O, and N) are useful for identifying recharge, water/rock ratios, and chemical equilibrium temperatures. Radioactive isotopes of certain elements (3H, 36Cl) encountered in groundwater may also be used to directly date waters from a geothermal reservoir. Isotopes can be measured in gas, water, or rocks samples, and their characteristics are used to identify important information regarding a hydrothermal system. Specific properties of the various isotopes used in geothermal exploration are discussed in the Physical Properties section of this page (below).

Analysis of 36Cl- isotopes and interpretation of 36Cl/Cl ratios of waters sampled from springs and drill holes in the Valles Caldera region indicated that deeply circulating meteoric waters derive their high chloride contents from Precambrian basement and Paleozoic rocks before ascending into more shallow volcaniclastic reservoirs, and that residence times for these waters are <100,000 years. 36Cl/Cl ratios also confirm previous classifications of the sampled waters as meteoric or thermal waters established by previous stable isotope results. Hydrogen isotope data have also been used at the Valles Caldera, NM to improve understanding of the hydrothermal system. Tritium (3H) concentrations obtained from steam condensed in a mudpot and from deep, hot (approx. 278°C) reservoir fluids from the Baca #13 geothermal well are 2.1 and 1.0 T.U., respectively. The deuterium (2H) contents of the fumarole steam, deep reservoir fluid, and local meteoric water were practically identical, suggesting the steam is derived from a reservoir whose water is mostly >50 years old, and that the hydrothermal system is recharged by slow percolation of rainwater through fractures in and around the caldera’s resurgent dome.

Williams and McKibben (1989) used oxygen isotope ratios to characterize geothermal fluids from the Salton Sea Geothermal System, California. Results showed that the higher temperature reservoir fluids had higher concentrations of 18O than the cooler fluids, and the relatively homogenous source fluids entering the system underwent a high degree of water-rock interaction.

Kennedy & Van Soest (2007) were able to correlate high 3He concentrations from surface waters with active crustal deformation. These results enabled the identification of mantle-derived fluids at the surface, and are indicative of areas with high levels of crustal permeability or magmatic activity. At the Long Valley Caldera, CA, rising helium isotope ratios in fumaroles at Mammoth Mountain were also correlated with increased seismic activity in 1989, suggesting that recent magmatic intrusions contribute to the heat input of the present hydrothermal system.

Related Techniques

Property "Subcategories" (as page type) with input value "</br></br></br>* Lab Analysis Techniques</br>** Fluid Lab Analysis</br>*** Compound and Elemental Analysis</br>*** Fluid Inclusion Analysis</br>*** Isotopic Analysis- Fluid</br>*** Mercury Vapor</br>*** Trace Element Analysis</br>** Rock Lab Analysis</br>*** Core Analysis</br>*** Cuttings Analysis</br>*** Isotopic Analysis- Rock</br>*** Over Core Stress</br>*** Paleomagnetic Measurements</br>*** Petrography Analysis</br>*** Rock Density</br>*** X-Ray Diffraction (XRD)</br>*** [[:X-Ray Fluorescence (XRF)|X-Ray Fluorescence (XRF)" contains invalid characters or is incomplete and therefore can cause unexpected results during a query or annotation process.

• Lab Analysis Techniques
  • Fluid Lab Analysis
    • Compound and Elemental Analysis
    • Fluid Inclusion Analysis
    • Isotopic Analysis- Fluid
    • Mercury Vapor
    • Trace Element Analysis
  • Rock Lab Analysis
    • Core Analysis
    • Cuttings Analysis
    • Isotopic Analysis- Rock
    • Over Core Stress
    • Paleomagnetic Measurements
    • Petrography Analysis
    • Rock Density
    • X-Ray Diffraction (XRD)
    • X-Ray Fluorescence (XRF)

Field Procedures

Liquid and/or gas samples are collected in the field at the surface or from wellbores. The Water Sampling and Gas Sampling technique pages should be consulted for specific details regarding standard sampling procedures of fluids in the field.

Physical Properties

Variations in bond strength result in mass-dependent isotopic fractionations as phase changes, fluid-rock reactions, and mineral precipitation occur in response to variations in temperature, pressure, and fluid chemistry.Using "ReferenceForhttp://serc.carleton.edu/research_education/geochemsheets/techniques/gassourcemassspec.html" as property chain is not permitted during the annotation process. The effects of fractionation are more pronounced for lighter elements, in which the mass differences between different isotopes of the same element are relatively large. Different compounds in equilibrium with one another will record different isotopic ratios as a result of mass-dependent fractionation, and the magnitude of these differences depends strongly on temperature. Using "ReferenceForhttp://serc.carleton.edu/research_education/geochemsheets/techniques/gassourcemassspec.html" as property chain is not permitted during the annotation process. These characteristics provide researchers with useful tools for interpreting isotope data from geothermal systems, based on the flux of different isotopes through various natural geochemical reservoirs. Chlorine is a common anion found in meteoric fluids and has three isotopes, two of which are stable and the third is radioactive. The two stable isotopes, 35Cl and 37Cl, are 12-15 orders of magnitude more abundant than the radioactive isotope, 36Cl. The half-life of 36Cl is 301,000 years and has proven useful for dating fluids in hydrothermal systems and other quaternary hydrologic systems.

The two stable isotopes of carbon commonly measured in isotope geochemistry are 12C and 13C. The 13C/12C ratio is used as an indicator of paleoclimate, and records the amount of fractionation that occurs through photosynthetic activity in plants. The radioactive isotope of carbon is 14C, and is routinely used in dating of organic materials. Carbon-14 has a half-life of 5,730 +/- 40 years, and decays to nitrogen-14.

Oxygen has three naturally occurring stable isotopes. 16O is by far the most abundant, followed by 18O, and finally 17O. Measurement of oxygen isotope ratios can be used for a variety of applications. In geothermal exploration and reservoir evaluation, 18O:16O ratios are used to determine origins of fluids (meteoric or magmatic) and if there is mixing with other hydrothermal fluids in the system.

Hydrogen has three naturally occurring isotopes. 1H is the most abundant, accounting for 99.98% of the Earth’s hydrogen, and has a nucleus that consists of a single proton. 2H, also known as deuterium, is a comparatively rare stable isotope, comprising 0.0026-0.0184% (by population) of hydrogen samples on Earth. The lower end of this range is typically encountered in samples of hydrogen gas, whereas ocean water usually shows higher levels of enrichment. The radioactive isotope of hydrogen encountered in nature is 3H, also known as tritium. It has a half-life of 12.43 years, and decays to the isotope helium-3 (3He). While small amounts of tritium form naturally through interactions between cosmic rays and atmospheric gases, the largest input of tritium in groundwater comes from atmospheric nuclear weapons testing, which began in 1952 and peaked in the mid-1960s.Using "ReferenceForhttp://water.usgs.gov/lab/3h3he/background/" as property chain is not permitted during the annotation process. This tritium bomb peak can be located through groundwater sampling to provide information on recharge rates of systems replenished by relatively young (<60 years) groundwater. More precise dating of groundwater can be performed through 3H/3He dating by comparing tritium concentrations to the amount of tritiogenic 3He in a sample.

Helium has two stable isotopes, 3He and 4He, with the latter having a much higher abundance at the earth surface, and the former having an increasing concentration with depth. This has allowed scientists to use 3He as a method for determining the source of fluids, mixing of fluids, interactions with various lithologies at depth, and anomalous heat sources. 3He/4He ratios are typically reported as R/Ra, where R is the isotopic ratio of helium measured in the sample and Ra is the present isotopic ratio of helium in the atmosphere. Scientists studying geothermal systems have also found a relationship of 3He and enthalpy of a reservoir. 3He is expelled from a magma twenty times more efficiently than heat, allowing high 3He ratios to be indicative of a heat source at depth.

Data Access and Acquisition

Photo of the plasma sampler from an ICP-MS system used by the Atomic Energy and Alternative Energies Commission (CEA), France. Photo from the CEA Website, last updated October 2, 2011.

Following collection, isotope data of a rock, liquid, or gas sample is analyzed using a mass spectrometer. A mass spectrometer is a device that is able to measure the composition of a sample and the mass-to-charge ratio of a particular element or molecule. First a sample is ionized, converting a fraction of the original sample into ions (charged particles)- there are numerous methods used for this process. The ions are then separated by the mass-to-charge ratio and measured by a sensitive instrument that is capable of detecting varying particle charges by magnetic sector, quadrupole, or time of flight. Finally the data is processed and plotted onto a spectra which displays the masses of the particles of that sample.

Schematic diagram of an ICP-MS system with metal speciation capability. Figure 1 from Caruso & Montes-Bayon (2003).

Best Practices

The applications of stable isotope geochemistry span all fields of the geosciences. Understanding of the fluxes of isotopes through different geochemical reservoirs is used to study many geological processes.Using "ReferenceForhttp://serc.carleton.edu/research_education/geochemsheets/techniques/gassourcemassspec.html" as property chain is not permitted during the annotation process. Based on these characteristics, and on the strong dependence of isotopic fractionation on temperature, stable isotopes can be used as a geochemical tracer in natural systems. The isotopic ratio of an element in rocks or other material can record the movement of elements through different geochemical reservoirs. If equilibrium conditions can be assumed, stable isotope ratios of two substances can also be used to approximate the temperature of exchange. This enables the application of certain chemical geothermometers.

Potential Pitfalls

Limitations of isotopic data and pitfalls in data interpretation are specific to the type of isotope data being considered. For example, there are several specific conditions that must be satisfied for precise determination of the age of a water sample using 3H/3He data (these parameters are explained in detail on the U.S. Geological Survey 3H/3He Dating Background webpage). A qualified hydrologist, geochemist, or geologist with sufficient background in isotope geochemistry should be consulted when interpreting isotope data.

Additional References

References

[edit]

Page	Area	Activity Start Date	Activity End Date	Reference Material
Isotopic Analysis (Klein, 2007)	Unspecified			Advances In The Past 20 Years- Geochemistry In Geothermal Exploration Resource Evaluation And Reservoir Management
Isotopic Analysis (Lewicki & Oldenburg)	Unspecified			Near-Surface Co2 Monitoring And Analysis To Detect Hidden Geothermal Systems
Isotopic Analysis (Lewicki & Oldenburg, 2004)	Unspecified			Strategies For Detecting Hidden Geothermal Systems By Near-Surface Gas Monitoring
Isotopic Analysis (Lewicki & Oldenburg, 2005)	Unspecified			Strategies To Detect Hidden Geothermal Systems Based On Monitoring and Analysis Of CO2 In The Near-Surface Environment
Isotopic Analysis (Not Available)	Unspecified			Advisory Group On The Application Of Nuclear Techniques To Geothermal Studies-Meeting In Pisa 8-12 Sep 1975
Isotopic Analysis At Buffalo Valley Hot Springs Area (Laney, 2005)	Buffalo Valley Hot Springs Area			Federal Geothermal Research Program Update - Fiscal Year 2004
Isotopic Analysis At Cascades Region (Kennedy & Van Soest, 2007)	Cascades Geothermal Region			Flow Of Mantle Fluids Through The Ductile Lower Crust- Helium Isotope Trends
Isotopic Analysis At Central Nevada Seismic Zone Region (Kennedy & Van Soest, 2007)	Central Nevada Seismic Zone Geothermal Region			Flow Of Mantle Fluids Through The Ductile Lower Crust- Helium Isotope Trends
Isotopic Analysis At Central Nevada Seismic Zone Region (Laney, 2005)	Central Nevada Seismic Zone Geothermal Region			Federal Geothermal Research Program Update - Fiscal Year 2004
Isotopic Analysis At Chena Geothermal Area (Holdmann, Et Al., 2006)	Chena Geothermal Area	2005	2007	Integrated Geoscience Investigation and Geothermal Exploration at Chena Hot Springs, Alaska
Isotopic Analysis At Clear Lake Area (Thompson, Et Al., 1992)	Clear Lake Area			Thermal Waters Along The Konocti Bay Fault Zone, Lake County, California- A Re-Evaluation
Isotopic Analysis At Geyser Bight Area (Motyka, Et Al., 1993)	Geyser Bight Area			The Geyser Bight Geothermal Area, Umnak Island, Alaska
Isotopic Analysis At Geysers Area (Kennedy & Truesdell, 1996)	Geysers Area			The Northwest Geysers High-Temperature Reservoir- Evidence For Active Magmatic Degassing And Implications For The Origin Of The Geysers Geothermal Field
Isotopic Analysis At Jemez Springs Area (Goff & Janik, 2002)	Jemez Springs Area			Gas Geochemistry Of The Valles Caldera Region, New Mexico And Comparisons With Gases At Yellowstone, Long Valley And Other Geothermal Systems
Isotopic Analysis At Jemez Springs Area (Goff, Et Al., 1981)	Jemez Springs Area			Geology, Water Geochemistry And Geothermal Potential Of The Jemez Springs Area, Canon De San Diego, New Mexico
Isotopic Analysis At Jemez Springs Area (Rao, Et Al., 1996)	Jemez Springs Area	1996	1996	Sources Of Chloride In Hydrothermal Fluids From The Valles Caldera, New Mexico- A 36Cl Study
Isotopic Analysis At Lake City Hot Springs Area (Sladek, Et Al., 2004)	Lake City Hot Springs Area			Geochemistry Of The Lake City Geothermal System, California, Usa
Isotopic Analysis At Lassen Volcanic National Park Area (Janik & Mclaren, 2010)	Lassen Volcanic National Park Area			Seismicity And Fluid Geochemistry At Lassen Volcanic National Park, California- Evidence For Two Circulation Cells In The Hydrothermal System
Isotopic Analysis At Long Valley Caldera Geothermal Area (Evans, Et Al., 2002)	Long Valley Caldera Geothermal Area		2002	Tracing And Quantifying Magmatic Carbon Discharge In Cold Groundwaters- Lessons Learned From Mammoth Mountain, USA
Isotopic Analysis At Long Valley Caldera Geothermal Area (Goff, Et Al., 1991)	Long Valley Caldera Geothermal Area	1985	1986	A Sr-Isotopic Comparison Between Thermal Waters, Rocks, And Hydrothermal Calcites, Long Valley Caldera, California
Isotopic Analysis At Long Valley Caldera Geothermal Area (Smith & Suemnicht, 1991)	Long Valley Caldera Geothermal Area	1985	1988	Oxygen Isotope Evidence For Past And Present Hydrothermal Regimes Of Long Valley Caldera, California
Isotopic Analysis At Mt St Helens Area (Shevenell & Goff, 1995)	Mt St Helens Area			Evolution Of Hydrothermal Waters At Mount St Helens, Washington, Usa
Isotopic Analysis At Mt St Helens Area (Shevenell & Goff, 2000)	Mt St Helens Area			Temporal Geochemical Variations In Volatile Emissions From Mount St Helens, Usa, 1980-1994
Isotopic Analysis At Newberry Caldera Area (Carothers, Et Al., 1987)	Newberry Caldera Area			Isotope Geochemistry Of Minerals And Fluids From Newberry Volcano, Oregon
Isotopic Analysis At Northern Basin & Range Region (Cole, 1983)	Northern Basin and Range Geothermal Region			Chemical And Isotopic Investigation Of Warm Springs Associated With Normal Faults In Utah
Isotopic Analysis At Northern Basin & Range Region (Kennedy & Van Soest, 2007)	Northern Basin and Range Geothermal Region			Flow Of Mantle Fluids Through The Ductile Lower Crust- Helium Isotope Trends
Isotopic Analysis At Northern Basin & Range Region (Laney, 2005)	Northern Basin and Range Geothermal Region			Federal Geothermal Research Program Update - Fiscal Year 2004
Isotopic Analysis At Nw Basin & Range Region (Kennedy & Van Soest, 2007)	Northwest Basin and Range Geothermal Region			Flow Of Mantle Fluids Through The Ductile Lower Crust- Helium Isotope Trends
Isotopic Analysis At Nw Basin & Range Region (Laney, 2005)	Northwest Basin and Range Geothermal Region			Federal Geothermal Research Program Update - Fiscal Year 2004
Isotopic Analysis At Reese River Area (Henkle & Ronne, 2008)	Reese River Area			Phase 2 Reese River Geothermal Project Slim Well 56-4 Drilling And Testing
Isotopic Analysis At Separation Creek Area (Van Soest, Et Al., 2002)	Separation Creek Geothermal Area			Mantle Helium And Carbon Isotopes In Separation Creek Geothermal Springs, Three Sisters Area, Central Oregon- Evidence For Renewed Volcanic Activity Or A Long Term Steady State System(Question)
Isotopic Analysis At U.S. West Region (Laney, 2005)	U.S. West Region			Federal Geothermal Research Program Update - Fiscal Year 2004
Isotopic Analysis At U.S. West Region (Welhan, Et Al., 1988)	U.S. West Region			Helium Isotopes In Geothermal And Volcanic Gases Of The Western United States, I, Regional Variability And Magmatic Origin
Isotopic Analysis At Valles Caldera - Redondo Geothermal Area (Goff, Et Al., 1982)	Valles Caldera - Redondo Geothermal Area		1982	Geochemical Data for 95 Thermal and Nonthermal Waters of the Valles Caldera - Southern Jemez Mountains Region, New Mexico
Isotopic Analysis At Valles Caldera - Redondo Geothermal Area (Janik & Goff, 2002)	Valles Caldera - Redondo Geothermal Area	1982	2002	Gas Geochemistry Of The Valles Caldera Region, New Mexico And Comparisons With Gases At Yellowstone, Long Valley And Other Geothermal Systems
Isotopic Analysis At Valles Caldera - Redondo Geothermal Area (Phillips, Et Al., 1984)	Valles Caldera - Redondo Geothermal Area		1984	36Cl as a tracer in geothermal systems- Example from Valles Caldera, New Mexico
Isotopic Analysis At Valles Caldera - Redondo Geothermal Area (White, 1986)	Valles Caldera - Redondo Geothermal Area		1986	Chemical and isotopic characteristics of fluids within the Baca Geothermal Reservoir, Valles Caldera, New Mexico
Isotopic Analysis At Valles Caldera - Redondo Geothermal Area (White, Et Al., 1992)	Valles Caldera - Redondo Geothermal Area		1992	Mass Transfer Constraints On The Chemical Evolution Of An Active Hydrothermal System, Valles Caldera, New Mexico
Isotopic Analysis At Valley Of Ten Thousand Smokes Region Area (Keith, Et Al., 1992)	Valley Of Ten Thousand Smokes Region Area			Geochemistry Of Waters In The Valley Of Ten Thousand Smokes Region, Alaska
Isotopic Analysis At Walker-Lane Transitional Zone Region (Kennedy & Van Soest, 2007)	Walker-Lane Transition Zone Geothermal Region			Flow Of Mantle Fluids Through The Ductile Lower Crust- Helium Isotope Trends
Isotopic Analysis At Walker-Lane Transitional Zone Region (Laney, 2005)	Walker-Lane Transition Zone Geothermal Region			Federal Geothermal Research Program Update - Fiscal Year 2004
Isotopic Analysis At Yellowstone Region (Goff & Janik, 2002)	Yellowstone Caldera Geothermal Region			Gas Geochemistry Of The Valles Caldera Region, New Mexico And Comparisons With Gases At Yellowstone, Long Valley And Other Geothermal Systems
Isotopic Analysis At Yellowstone Region (Sturchio, Et Al., 1990)	Yellowstone Caldera Geothermal Region			Oxygen And Carbon Isotope Ratios Of Hydrothermal Minerals From Yellowstone Drill Cores
Isotopic Analysis Fluid At Coso Geothermal Area (1997)	Coso Geothermal Area	1997	1997	36Cl/Cl ratios in geothermal systems- preliminary measurements from the Coso Field
Isotopic Analysis- Fluid At Chena Area (Erkan, Et. Al., 2008)	Chena Area			Understanding The Chena Hot Springs, Alaska, Geothermal System Using Temperature And Pressure Data From Exploration Boreholes
Isotopic Analysis- Fluid At Coso Geothermal Area (1982)	Coso Geothermal Area	1982	1982	An isotopic study of the Coso, California, geothermal area
Isotopic Analysis- Fluid At Coso Geothermal Area (1990)	Coso Geothermal Area	1990	1990	Water geochemistry study of Indian Wells Valley, Inyo and Kern Counties, California. Supplement. Isotope geochemistry and Appendix H. Final report
Isotopic Analysis- Fluid At Coso Geothermal Area (2007)	Coso Geothermal Area	2007	2007	Chemical and isotopic characteristics of the coso east flank hydrothermal fluids: implications for the location and nature of the heat source
Isotopic Analysis- Fluid At Dixie Valley Geothermal Area (Kennedy & Soest, 2005)	Dixie Valley Geothermal Area	2004	2005	Federal Geothermal Research Program Update - Fiscal Year 2004 Regional And Local Trends In Helium Isotopes, Basin And Range Province, Western North America- Evidence For Deep Permeable Pathways
Isotopic Analysis- Fluid At Fenton Hill HDR Geothermal Area (Goff & Janik, 2002)	Fenton Hill HDR Geothermal Area	1982	2002	Gas Geochemistry Of The Valles Caldera Region, New Mexico And Comparisons With Gases At Yellowstone, Long Valley And Other Geothermal Systems
Isotopic Analysis- Fluid At Fenton Hill HDR Geothermal Area (Goff, Et Al., 1981)	Fenton Hill HDR Geothermal Area		1981	Geology, Water Geochemistry And Geothermal Potential Of The Jemez Springs Area, Canon De San Diego, New Mexico
Isotopic Analysis- Fluid At Fenton Hill HDR Geothermal Area (Grigsby, Et Al., 1989)	Fenton Hill HDR Geothermal Area		1989	Rock-Water Interactions in the Fenton Hill, New Mexico, Hot Dry Rock Geothermal Systems I. Fluid Mixing and Chemical Geothermometry
Isotopic Analysis- Fluid At Fenton Hill HDR Geothermal Area (Rao, Et Al., 1996)	Fenton Hill HDR Geothermal Area	1996	1996	Sources Of Chloride In Hydrothermal Fluids From The Valles Caldera, New Mexico- A 36Cl Study
Isotopic Analysis- Fluid At Indian Valley Hot Springs Geothermal Area (1990)	Indian Valley Hot Springs Geothermal Area	1990	1990	Water geochemistry study of Indian Wells Valley, Inyo and Kern Counties, California. Supplement. Isotope geochemistry and Appendix H. Final report
Isotopic Analysis- Fluid At Kilauea East Rift Geothermal Area (Scholl, Et Al., 1993)	Kilauea East Rift Geothermal Area	1992	1992	Preliminary results from an isotope hydrology study of the Kilauea Volcano area, Hawaii
Isotopic Analysis- Fluid At Lightning Dock Geothermal Area (Witcher, 2006)	Lightning Dock Geothermal Area			GRED Studies and Drilling of Americulture State 2, Americulture Tilapia Farm: Lightning Dock KGRA, Las Animas Valley, New Mexico
Isotopic Analysis- Fluid At Long Valley Caldera Geothermal Area (Farrar, Et Al., 2003)	Long Valley Caldera Geothermal Area	2000	2001	Inferences On The Hydrothermal System Beneath The Resurgent Dome In Long Valley Caldera, East-Central California, USA, From Recent Pumping Tests And Geochemical Sampling
Isotopic Analysis- Fluid At Long Valley Caldera Geothermal Area (Sorey, Et Al., 1991)	Long Valley Caldera Geothermal Area	1985	1988	New Evidence On The Hydrothermal System In Long Valley Caldera, California, From Wells, Fluid Sampling, Electrical Geophysics, And Age Determinations Of Hot-Spring Deposits
Isotopic Analysis- Fluid At Long Valley Caldera Geothermal Area (Taylor & Gerlach, 1983)	Long Valley Caldera Geothermal Area	1983	1986	New Evidence On The Hydrothermal System In Long Valley Caldera, California, From Wells, Fluid Sampling, Electrical Geophysics, And Age Determinations Of Hot-Spring Deposits Chemical and Isotopic Composition of Casa Diablo Hot Spring: Magmatic CO2 near Mammoth Lakes, CA Isotopic Composition of Carbon in Fluids from the Long Valley Geothermal System, California, In- Proceedings of the Second Workshop on Hydrologic and Geochemical Monitoring in the Long Valley Caldera
Isotopic Analysis- Fluid At Roosevelt Hot Springs Geothermal Area (Faulder, 1991)	Roosevelt Hot Springs Geothermal Area	1981	1981	Conceptual Geologic Model and Native State Model of the Roosevelt Hot Springs Hydrothermal System
Isotopic Analysis- Fluid At Roosevelt Hot Springs Geothermal Area (Ward, Et Al., 1978)	Roosevelt Hot Springs Geothermal Area	1978	1978	A Summary of the Geology, Geochemistry, and Geophysics of the Roosevelt Hot Springs Thermal Area, Utah
Isotopic Analysis- Fluid At Rose Valley Geothermal Area (1990)	Rose Valley Geothermal Area	1990	1990	Water geochemistry study of Indian Wells Valley, Inyo and Kern Counties, California. Supplement. Isotope geochemistry and Appendix H. Final report
Isotopic Analysis- Fluid At Salt Wells Area (Shevenell & Garside, 2003)	Salt Wells Geothermal Area	2002	2002	Geochemical Sampling of Thermal Waters in Nevada
Isotopic Analysis- Fluid At Sierra Valley Geothermal Area (1990)	Sierra Valley Geothermal Area	1990	1990	Water geochemistry study of Indian Wells Valley, Inyo and Kern Counties, California. Supplement. Isotope geochemistry and Appendix H. Final report
Isotopic Analysis- Fluid At Valles Caldera - Redondo Area (Rao, Et Al., 1996)	Valles Caldera - Redondo Area	1996	1996	Sources Of Chloride In Hydrothermal Fluids From The Valles Caldera, New Mexico- A 36Cl Study
Isotopic Analysis- Fluid At Valles Caldera - Redondo Geothermal Area (Musgrave, Et Al., 1989)	Valles Caldera - Redondo Geothermal Area		1989	Selected Data from Continental Scientific Drilling Core Holes VC-1 and VC-2A, Valles Caldera, New Mexico
Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Area (Rao, Et Al., 1996)	Valles Caldera - Sulphur Springs Geothermal Area	1996	1996	Sources Of Chloride In Hydrothermal Fluids From The Valles Caldera, New Mexico- A 36Cl Study
Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Geothermal Area (Goff, Et Al., 1982)	Valles Caldera - Sulphur Springs Geothermal Area		1982	Geochemical Data for 95 Thermal and Nonthermal Waters of the Valles Caldera - Southern Jemez Mountains Region, New Mexico
Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Geothermal Area (Goff, Et Al., 1985)	Valles Caldera - Sulphur Springs Geothermal Area		1985	Geochemistry and Isotopes of Fluids from Sulphur Springs, Valles Caldera, New Mexico
Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Geothermal Area (Janik & Goff, 2002)	Valles Caldera - Sulphur Springs Geothermal Area		2002	Gas Geochemistry Of The Valles Caldera Region, New Mexico And Comparisons With Gases At Yellowstone, Long Valley And Other Geothermal Systems
Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Geothermal Area (Musgrave, Et Al., 1989)	Valles Caldera - Sulphur Springs Geothermal Area		1989	Selected Data from Continental Scientific Drilling Core Holes VC-1 and VC-2A, Valles Caldera, New Mexico
Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Geothermal Area (White, Et Al., 1992)	Valles Caldera - Sulphur Springs Geothermal Area		1992	Mass Transfer Constraints On The Chemical Evolution Of An Active Hydrothermal System, Valles Caldera, New Mexico
Isotopic Analysis- Gas At Chena Geothermal Area (Kolker, Et Al., 2008)	Chena Geothermal Area	2007	2007	Evidence for a Crustal Heat Source for Low-Temperature Geothermal Systems in the Central Alaskan Hot Springs Belt
Isotopic Analysis- Gas At Long Valley Caldera Geothermal Area (Farrar, Et Al., 2003)	Long Valley Caldera Geothermal Area	2000	2001	Tracing And Quantifying Magmatic Carbon Discharge In Cold Groundwaters- Lessons Learned From Mammoth Mountain, USA Inferences On The Hydrothermal System Beneath The Resurgent Dome In Long Valley Caldera, East-Central California, USA, From Recent Pumping Tests And Geochemical Sampling Carbon Dioxide and Helium Emissions from a Reservoir of Magmatic Gas Beneath Mammoth Mountain, California
Isotopic Analysis- Gas At Long Valley Caldera Geothermal Area (Welhan, Et Al., 1988)	Long Valley Caldera Geothermal Area	1988	1990	Gas Geochemistry Of The Valles Caldera Region, New Mexico And Comparisons With Gases At Yellowstone, Long Valley And Other Geothermal Systems The 1989 Earthquake Swarm Beneath Mammoth Mountain, California: An Initial Look at the 4 May Through 30 September Activity Increases in 3He/4He in Fumarolic Gas Associated with the 1989 Earthquake Swarm Beneath Mammoth Mountain, California Helium Isotopes in Geothermal and Volcanic Gases of the Western United States, II. Long Valley Caldera Isotopic Composition of Carbon in Fluids from the Long Valley Geothermal System, California, In- Proceedings of the Second Workshop on Hydrologic and Geochemical Monitoring in the Long Valley Caldera
Isotopic Analysis-Fluid At Long Valley Caldera Geothermal Area (1977)	Long Valley Caldera Geothermal Area	1977	1977	Geothermal reservoir temperatures estimated from the oxygen isotope compositions of dissolved sulfate and water from hot springs and shallow drillholes
Isotopic Analysis-Fluid At Long Valley Caldera Geothermal Area (McKenzie & Truesdell, 1977)	Long Valley Caldera Geothermal Area	1976	1977	Geochemistry of Thermal Waters in Long Valley, Mono County, California Geothermal Reservoir Temperatures Estimated from the Oxygen Isotope Compositions of Dissolved Sulfate and Water from Hot Springs and Shallow Drillholes
Isotopic Analysis-Fluid At Raft River Geothermal Area (1977)	Raft River Geothermal Area	1977	1977	Geothermal reservoir temperatures estimated from the oxygen isotope compositions of dissolved sulfate and water from hot springs and shallow drillholes
Isotopic Analysis-Fluid At Raft River Geothermal Area (1982)	Raft River Geothermal Area	1982	1982	Chemical and light-stable isotope characteristics of waters from the raft river geothermal area and environs, Cassia County, Idaho, Box Elder county, Utah Helium isotopes in geothermal systems- Iceland, The Geysers, Raft River and Steamboat Springs

[edit]

1. Unspecified
2. Buffalo Valley Hot Springs Area
3. Cascades Geothermal Region
4. Central Nevada Seismic Zone Geothermal Region
5. Chena Geothermal Area
6. Clear Lake Area
7. Geyser Bight Area
8. Geysers Area
9. Jemez Springs Area
10. Lake City Hot Springs Area
11. Lassen Volcanic National Park Area
12. Long Valley Caldera Geothermal Area
13. Mt St Helens Area
14. Newberry Caldera Area
15. Northern Basin and Range Geothermal Region
16. Northwest Basin and Range Geothermal Region
17. Reese River Area
18. Separation Creek Geothermal Area
19. U.S. West Region
20. Valles Caldera - Redondo Geothermal Area
21. Valley Of Ten Thousand Smokes Region Area
22. Walker-Lane Transition Zone Geothermal Region
23. Yellowstone Caldera Geothermal Region
24. Coso Geothermal Area
25. Chena Area
26. Dixie Valley Geothermal Area
27. Fenton Hill HDR Geothermal Area
28. Indian Valley Hot Springs Geothermal Area
29. Kilauea East Rift Geothermal Area
30. Lightning Dock Geothermal Area
31. Roosevelt Hot Springs Geothermal Area
32. Rose Valley Geothermal Area
33. Salt Wells Geothermal Area
34. Sierra Valley Geothermal Area
35. Valles Caldera - Redondo Area
36. Valles Caldera - Sulphur Springs Geothermal Area
37. Raft River Geothermal Area

[edit]

1. Cascades Geothermal Region
2. Central Nevada Seismic Zone Geothermal Region
3. Northern Basin and Range Geothermal Region
4. Northwest Basin and Range Geothermal Region
5. Walker-Lane Transition Zone Geothermal Region
6. Yellowstone Caldera Geothermal Region

[edit]

{{}}