A Hydrogeochemical Assessment of Geothermal Resources in ... · Known geothermal indicators used to...
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RESEARCH POSTER PRESENTATION DESIGN © 2015 www.PosterPresentations.com The Hawaiian Islands originate from hotspot volcanism. Each volcano typically experiences four stages of life: pre-shield, shield-building, post-shield and rejuvenation volcanism. Active or residual heat from intrusive magma below calderas, rift zones, and vents may manifest in a geothermal resource. Previous research has provided evidence suggesting residual heat from late stage volcanism may contribute geothermal heat. For example the island of Kauai, shield stage of volcanism approximately five million years old, has the largest volume of rejuvenation phase lavas and warm water wells on the surface. 1,2 . Geothermal research in Hawaii began in the 1960’s. In the 1970’s and 1980’s, the National Science Foundation (NSF) and the University of Hawaii began exploratory research in the Kilauea East Rift Zone on the Island of Hawaii, and in 1985, the last geothermal resource assessment was presented 2 . In 1993, the Puna Geothermal Venture plant, operated by Ormat Technologies, Inc., began commercial operations and has been operating continuously since. The United States Department of Energy has invested in geothermal research across the nation, with Hawaii participating in the Play Fairway Analysis for the past few years 3 . In 2015 Hawaii Governor David Ige signed House Bill 623 as part of the Hawaii Clean Energy Initiative, targeting 100% renewable energy for Hawaii by 2045. Residents in Hawaii pay about 37 Cents/kWh, almost three times the national average, with geothermal contributing only 2.3% of electricity production in 2015 4 . To achieve this goal the State of Hawaii will need to consider renewable energy sources, of which geothermal may be the only viable baseload option. INTRODUCTION OBJECTIVES AND METHODS RESULTS The comparison of Cl to Mg abundance has been previously used as a geothermal indicator in Hawaiian geothermal fluids 6 . Cl content in seawater and groundwater remains unchanged by thermal processes, whereas Mg is strongly depleted in geothermally heated groundwater 6 . Ratios greater than 15 indicate anomalous thermal conditions in the subsurface. The Play Fairway Phase II data is shown, with geothermal production wells added as reference, with Cl:Mg ratio lines to show anomalous values (Figure 4). The bimodal grouping represents chemically similar water sources 6 . REFERENCES 1 Thomas et al., 1979, Haw. Inst. Of Geo. Tech. Rept.; 2 Thomas, 1985, Haw. Inst. Of Geo. Tech. Rept.; 3 Lautze et al., 2017, Geothermics; 4 DBEDT Hawaii, 2017; 5 Ito et al., 2017, Geothermics; 6 Cox and Thomas, 1979, Haw. Inst. Of Geo. Tech. Rept.; 67 Mahon, 1966, N.Z. J. Sci.; 8 Fournier and Rowe, 1966, Am. J. Sci.; 9 Ellis, 1970, Geothermics; 10 Fournier and Truesdell, 1970, Geothermics; 11 McMurtry et al., 1977, Am. J. Sci; 12 Davis, 1969, Water Resources Research Center Tech. Rept. ACKNOWLEDGEMENTS We thank the U.S. Department of Energy’s Geothermal Technologies Program for providing funding and management of this project, under award number DE-EE6729. Thank you to the Play Fairway team – Dr. Nicole Lautze, Dr. Donald Thomas, Nicholas Hinz, Dr. Neil Frazer, Dr. Garrett Ito, Robert Whittier, David Waller, and other contributors. We also thank Kyushu University Platform of Inter-/Transdisciplinary Energy Research (Q- PIT) for the opportunity to share our research. For more information, visit our website: https://www.higp.hawaii.edu/hggrc/ The Play Fairway Analysis Phase I Project at the University of Hawaii at Manoa (UHM) collected all available geothermal data, including geological, geochemical and geophysical. Phase I developed a systematic approach to the analysis of geothermal-relevant data in Hawaii, and also provided this method to be easily adaptable to other resource areas (Figure 1). This probability model was used to determine study sites for new data collection in Phase II 5 . 1 Geology & Geophysics, University of Hawaii at Manoa, Honolulu, Hawaii 96822, 2 Hawaii Institute of Geophysics and Planetology, University of Hawaii at Manoa, Honolulu, Hawaii 96822 * [email protected] Diamond K. Tachera* 1 , Nicole C. Lautze 2 A Hydrogeochemical Assessment of Geothermal Resources in the State of Hawaii Heat Fluid Permeability Well Temp, MT (9) Cl/Mg ratio, (8) Caldera (7) Rift Zone, Gravity, SiO 2 (6) Vent, Dikes (4-5) Hawaiian Place Name (3) MT (9-10) Water level elevations (9-10) Recharge (9) Rift Zone, Faults (8) Geodetic Strain (8) Seismicity (8) Gravity (6) Probability of a successful play GEOLOGICAL, GEOPHYSICAL, and GROUNDWATER data Groundwater samples were collected from 60 wells and 1 freshwater spring across the State of Hawaii. Study sites were chosen based on the probability model, and are shown in red boxes (Figure 2). Water quality parameters, including temperature, pH, specific conductivity and dissolved oxygen, were collected in the field using a YSI Multi-Parameter Sonde (Figure 3). All samples were analyzed on the UHM campus, including: • Isotopes – δD, δ 18 O, δ 13 C • Major Ions – Ca, Mg, K, Li, Na, Cl, SO 4 , HCO 3 , SiO 2 • Trace Metals – Pb, As, Fe • Fluorescence – Microbial activity Chemical species in geothermal fluids can be divided into two groups: tracers or geoindicators. Tracers are chemically inert and non-reactive, leaving them unchanged as they move (i.e., Cl). Geoindicators are chemically reactive, and respond to the changing environments (i.e., Mg). A chemical exchange occurs between water and rocks, and is accelerated under unique conditions such as geothermal heating. An abundance of ions due to dissolution, or a depletion of ions due to secondary mineral formation, can be key indicators for geothermal heat present in the subsurface. We use the water geochemistry as a pre-drilling technique to extract information unobtainable by geologic or geophysical methods. Known geothermal indicators used to explore areas for geothermal resources include Cl vs. Mg ratios and SiO 2 abundance. A single indicator cannot be used alone, as there are many factors to consider (land use, contamination, etc.) when analyzing water chemistry for geothermal exploration. Therefore, we use a few indicators in conjunction to gain higher confidence in the resource. Figure 1 Figure 2 Figure 3 Geothermal power is an energy resource in Hawaii and Japan. As of 2015, Japan had 520 MW and Hawaii had 38 MW of geothermally generated electricity. Geophysical and geological exploration techniques have been applied in search of viable geothermal resources. The biggest hurdle in geothermal development in Japan is that most areas with active volcanoes are located in national park lands. Similar issues occur in Hawaii, with current volcanism located within Hawaii Volcanoes National Park. Additional areas of geothermal interest, such as onsen (hot springs), are popular tourist destinations. Local communities are resistant to development to maintain the pristine condition of these regions. Similar situations occur COLLABORATION WITH KYUSHU UNIVERSITY Figure 4 Figure 5 Figure 8 By Shigeru23, Wikipedia Figure 7 HIGP, UH Manoa in Hawaii, with local organizations protesting geothermal in order to preserve and perpetuate Native Hawaiian traditional rights, customs, and practices. Utilization of the Play Fairway statistical method can provide insight into viable locations of geothermal development in Japan. The statistical approach is easily adaptable to other geothermal regions around the world, taking into account heat, fluid and permeability data. We look forward to executing this approach for Japan, in collaboration with Kyushu University. 15 ppm 60 ppm 85 ppm Figure 6 Puna Geothermal Venture 38MW SiO 2 is a dissolved constituent in groundwater that originates in the basaltic rock. It has been used around the world as an indicator of subsurface heat 7-11 . In Hawaii, previous research has shown that rainwater has a SiO 2 concentration of 1 to 3 ppm as it interacts with the ground surface, 15 to 45 ppm as it moves through the groundwater aquifer, and 30 to 60 ppm as it resides in high level aquifers 12 . Recirculation by irrigation and reinjection of industrial waters can provide values up to 50 to 85 ppm; therefore, it can create uncertainty in its viability in determining geothermal heat. When analyzing the SiO 2 data collected during the Play Fairway project, we compared it to land cover maps as a first step to determine if contamination from irrigation was possible. The combination of Phase I and Phase II data are plotted on land usage maps to show SiO 2 distribution (Figure 5), and SiO 2 concentrations from Play Fairway Phase II are shown (Figure 6). These datasets are put into the statistical method to determine the probability of a successful geothermal resource.
Transcript of A Hydrogeochemical Assessment of Geothermal Resources in ... · Known geothermal indicators used to...
RESEARCH POSTER PRESENTATION DESIGN © 2015
www.PosterPresentations.com
The Hawaiian Islands originate from hotspot volcanism. Each volcano typically experiences four stages of life: pre-shield, shield-building, post-shield and rejuvenation volcanism. Active or residual heat from intrusive magma below calderas, rift zones, and vents may manifest in a geothermal resource. Previous research has provided evidence suggesting residual heat from late stage volcanism may contribute geothermal heat. For example the island of Kauai, shield stage of volcanism approximately five million years old, has the largest volume of rejuvenation phase lavas and warm water wells on the surface.1,2. Geothermal research in Hawaii began in the 1960’s. In the 1970’s and 1980’s, the National Science Foundation (NSF) and the University of Hawaii began exploratory research in the Kilauea East Rift Zone on the Island of Hawaii, and in 1985, the last geothermal resource assessment was presented2. In 1993, the Puna Geothermal Venture plant, operated by OrmatTechnologies, Inc., began commercial operations and has been operating continuously since. The United States Department of Energy has invested in geothermal research across the nation, with Hawaii participating in the Play Fairway Analysis for the past few years3.In 2015 Hawaii Governor David Ige signed House Bill 623 as part of the Hawaii Clean Energy Initiative, targeting 100% renewable energy for Hawaii by 2045. Residents in Hawaii pay about 37 Cents/kWh, almost three times the national average, with geothermal contributing only 2.3% of electricity production in 20154. To achieve this goal the State of Hawaii will need to consider renewable energy sources, of which geothermal may be the only viable baseload option.
INTRODUCTION
OBJECTIVES AND METHODS
RESULTSThe comparison of Cl to Mg abundance has been previously used as a geothermal indicator in Hawaiian geothermal fluids6. Cl content in seawater and groundwater remains unchanged by thermal processes, whereas Mg is strongly depleted in geothermally heated groundwater6. Ratios greater than 15 indicate anomalous thermal conditions in the subsurface. The Play Fairway Phase II data is shown, with geothermal production wells added as reference, with Cl:Mg ratio lines to show anomalous values (Figure 4). The bimodal grouping represents chemically similar water sources6.
REFERENCES1Thomas et al., 1979, Haw. Inst. Of Geo. Tech. Rept.; 2Thomas, 1985, Haw. Inst. Of Geo. Tech. Rept.; 3Lautze et al., 2017, Geothermics; 4DBEDT Hawaii, 2017; 5Ito et al., 2017, Geothermics; 6Cox and Thomas, 1979, Haw. Inst. Of Geo. Tech. Rept.; 67Mahon, 1966, N.Z. J. Sci.; 8Fournier and Rowe, 1966, Am. J. Sci.; 9Ellis, 1970, Geothermics; 10Fournier and Truesdell, 1970, Geothermics; 11McMurtry et al., 1977, Am. J. Sci; 12Davis, 1969, Water Resources Research Center Tech. Rept.
ACKNOWLEDGEMENTSWe thank the U.S. Department of Energy’s Geothermal Technologies Program for providing funding and management of this project, under award number DE-EE6729. Thank you to the Play Fairway team – Dr. Nicole Lautze, Dr. Donald Thomas, Nicholas Hinz, Dr. Neil Frazer, Dr. Garrett Ito, Robert Whittier, David Waller, and other contributors. We also thank Kyushu University Platform of Inter-/Transdisciplinary Energy Research (Q-PIT) for the opportunity to share our research.
For more information, visit our website: https://www.higp.hawaii.edu/hggrc/
The Play Fairway Analysis Phase I Project at the University of Hawaii at Manoa (UHM) collected all available geothermal data, including geological, geochemical and geophysical. Phase I developed a systematic approach to the analysis of geothermal-relevant data in Hawaii, and also provided this method to be easily adaptable to other resource areas (Figure 1). This probability model was used to determine study sites for new data collection in Phase II5.
1Geology & Geophysics, University of Hawaii at Manoa, Honolulu, Hawaii 96822, 2Hawaii Institute of Geophysics and Planetology, University of Hawaii at Manoa, Honolulu, Hawaii 96822*[email protected]
Diamond K. Tachera*1, Nicole C. Lautze2
A Hydrogeochemical Assessment of Geothermal Resources in the State of Hawaii
Heat Fluid Permeability
Well Temp, MT (9)Cl/Mg ratio, (8)
Caldera (7)Rift Zone, Gravity, SiO2 (6)
Vent, Dikes (4-5)Hawaiian Place Name (3)
MT (9-10)Water level elevations (9-10)
Recharge (9)
Rift Zone, Faults (8)Geodetic Strain (8)
Seismicity (8)Gravity (6)
Probability of a successful play
GEOLOGICAL, GEOPHYSICAL, and GROUNDWATER data
Groundwater samples were collected from 60 wells and 1 freshwater spring across the State of Hawaii. Study sites were chosen based on the probability model, and are shown in red boxes (Figure 2). Water quality parameters, including temperature, pH, specific conductivity and dissolved oxygen, were collected in the field using a YSI Multi-Parameter Sonde(Figure 3). All samples were analyzed on the UHM campus, including:• Isotopes – δD, δ18O, δ13C• Major Ions – Ca, Mg, K, Li, Na,
Cl, SO4, HCO3, SiO2
• Trace Metals – Pb, As, Fe• Fluorescence – Microbial
activityChemical species in geothermal fluids can be divided into twogroups: tracers or geoindicators. Tracers are chemically inert and non-reactive, leaving them unchanged as they move (i.e., Cl). Geoindicators are chemically reactive, and respond to the changing environments (i.e., Mg). A chemical exchange occurs between water and rocks, and is accelerated under unique conditions such as geothermal heating. An abundance of ions due to dissolution, or a depletion of ions due to secondary mineral formation, can be key indicators for geothermal heat present in the subsurface. We use the water geochemistry as a pre-drilling technique to extract information unobtainable by geologic or geophysical methods.Known geothermal indicators used to explore areas for geothermal resources include Cl vs. Mg ratios and SiO2 abundance. A single indicator cannot be used alone, as there are many factors to consider (land use, contamination, etc.) when analyzing water chemistry for geothermal exploration. Therefore, we use a few indicators in conjunction to gain higher confidence in the resource.
Figure 1
Figure 2
Figure 3
Geothermal power is an energy resource in Hawaii and Japan. As of 2015, Japan had 520 MW and Hawaii had 38 MW of geothermally generated electricity. Geophysical and geological exploration techniques have been applied in search of viable geothermal resources. The biggest hurdle in geothermal development in Japan is that most areas with active volcanoes are located in national park lands. Similar issues occur in Hawaii, with current volcanism located within Hawaii Volcanoes National Park.Additional areas of geothermal interest, such as onsen (hot springs), are popular tourist destinations. Local communities are resistant to development to maintain the pristine condition of these regions. Similar situations occur
COLLABORATION WITH KYUSHU UNIVERSITY
Figure 4
Figure 5
Figure 8By Shigeru23, Wikipedia
Figure 7HIGP, UH Manoa
in Hawaii, with local organizations protesting geothermal in order to preserve and perpetuate Native Hawaiian traditional rights, customs, and practices.Utilization of the Play Fairway statistical method can provide insight into viable locations of geothermal development in Japan. The statistical approach is easily adaptable to other geothermal regions around the world, taking into account heat, fluid and permeability data. We look forward to executing this approach for Japan, in collaboration with Kyushu University.
15 ppm
60 ppm85 ppm
Figure 6
PunaGeothermal
Venture 38MW
SiO2 is a dissolved constituent in groundwater that originates in the basaltic rock. It has been used around the world as an indicator of subsurface heat7-11. In Hawaii, previous research has shown that rainwater has a SiO2 concentration of 1 to 3 ppm as it interacts with the ground surface, 15 to 45 ppm as it moves through the groundwater aquifer, and 30 to 60 ppm as it resides in high level aquifers12. Recirculation by irrigation and reinjection of industrial waters can provide values up to 50 to 85 ppm; therefore, it can create uncertainty in its viability in determining geothermal heat. When analyzing the SiO2 data collected during the Play Fairway project, we compared it to land cover maps as a first step to determine if contamination from irrigation was possible. The combination of Phase I and Phase II data are plotted on land usage maps to show SiO2 distribution (Figure 5), and SiO2 concentrations from Play Fairway Phase II are shown (Figure 6). These datasets are put into the statistical method to determine the probability of a successful geothermal resource.
