Sample records for lake geothermal area

  1. [Hydrogen and oxygen isotopes of lake water and geothermal spring water in arid area of south Tibet].

    PubMed

    Xiao, Ke; Shen, Li-Cheng; Wang, Peng

    2014-08-01

    The condition of water cycles in Tibet Plateau is a complex process, and the hydrogen and oxygen isotopes contain important information of this process. Based on the analysis of isotopic composition of freshwater lake, saltwater lake and geothermal water in the southern Tibetan Plateau, this study investigated water cycling, composition and variation of hydrogen and oxygen isotopes and the influencing factors in the study area. The study found that the mean values of delta18O and deltaD in Daggyaima lake water (-17.0 per thousand for delta18O and -138. 6 per thousand for deltaD), Langcuo lake water (-6.4 per thousand for delta18O and -87.4 per thousand for deltaD) and Dagejia geothermal water (-19.2 per thousand for delta18 and -158.2 per thousand for deltaD) all showed negative delta18O and deltaD values in Tibetan Plateau by the influence of altitude effects. Lake water and geothermal water were influenced by evaporation effects in inland arid area, and the slope of evaporation line was less than 8. Deuterium excess parameters of lake water and geothermal water were all negative. The temperature of geothermal reservoirs in Dagejia geothermal field was high,and oxygen shift existed in the relationship of hydrogen and oxygen isotopes.

  2. The Geysers-Clear Lake geothermal area, California - an updated geophysical perspective of heat sources

    USGS Publications Warehouse

    Stanley, W.D.; Blakely, R.J.

    1995-01-01

    The Geysers-Clear Lake geothermal area encompasses a large dry-steam production area in The Geysers field and a documented high-temperature, high-pressure, water-dominated system in the area largely south of Clear Lake, which has not been developed. An updated view is presented of the geological/geophysical complexities of the crust in this region in order to address key unanswered questions about the heat source and tectonics. Forward modeling, multidimensional inversions, and ideal body analysis of the gravity data, new electromagnetic sounding models, and arguments made from other geophysical data sets suggest that many of the geophysical anomalies have significant contributions from rock property and physical state variations in the upper 7 km and not from "magma' at greater depths. Regional tectonic and magmatic processes are analyzed to develop an updated scenario for pluton emplacement that differs substantially from earlier interpretations. In addition, a rationale is outlined for future exploration for geothermal resources in The Geysers-Clear Lake area. -from Authors

  3. SKY LAKES ROADLESS AREA AND MOUNTAIN LAKES WILDERNESS, OREGON.

    USGS Publications Warehouse

    Smith, James G.; Benham, John R.

    1984-01-01

    Based on a mineral survey of the Sky Lakes Roadless Area and the Mountain Lakes Wilderness, Oregon, the areas have little or no promise for the occurrence of metallic-mineral resources or geothermal energy resources. Nonmetallic resources exist in the areas, but other areas outside the roadless area and wilderness also contain resources of volcanic cinders, scoria, ash, breccia, and sand and gravel which are easier to obtain and closer to markets. The roadless area and wilderness are not geologically favorable for metallic deposits, or for coal, oil, or gas resources.

  4. Integrated exploration for low-temperature geothermal resources in the Honey Lake Basin, California

    USGS Publications Warehouse

    Schimschal, U.

    1991-01-01

    An integrated exploration study is presented to locate low-temperature geothermal reservoirs in the Honey Lake area of northern California. Regional studies to locate the geothermal resources included gravity, infra-red, water-temperature, and water-quality analyses. Five anomalies were mapped from resistivity surveys. Additional study of three anomalies by temperature-gradient and seismic methods was undertaken to define structure and potential of the geothermal resource. The gravity data show a graben structure in the area. Seismic reflection data indicate faults associated with surface-resistivity and temperature-gradient data. The data support the interpretation that the shallow reservoirs are replenished along the fault zones by deeply circulating heated meteoric waters. -Author

  5. Petrologic considerations for hot dry rock geothermal site selection in the Clear Lake Region, California

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stimac, J.; Goff, F.; Hearn, B.C. Jr.

    1992-01-01

    The Clear Lake area is well known for anomalous heat flow, thermal springs, hydrothermal mineral deposits, and Quaternary volcanism. These factors, along with the apparent lack of a large reservoir of geothermal fluid north of Collayomi fault make the Clear Lake area an attractive target for hot dry rock (HDR) geothermal development. Petrologic considerations provide some constraints on site selection for HDR development. Spatial and temporal trends in volcanism in the Coast Ranges indicate that magmatism has migrated to the north with time, paralleling passage of the Mendocino triple junction and propagation of the San Andreas fault. Volcanism in themore » region may have resulted from upwelling of hot asthenosphere along the southern margin of the subducted segment of the Gorda plate. Spatial and temporal trends of volcanism within the Clear Lake volcanic field are similar to larger-scale trends of Neogene volcanism in the Cost Ranges. Volcanism (especially for silicic compositions) shows a general migration to the north over the {approximately}2 Ma history of the field, with the youngest two silicic centers located at Mt. Konocti and Borax Lake. The Mt. Konocti system (active from {approximately} 0.6 to 0.3 Ma) was large and long-lived, whereas the Borax Lake system is much smaller but younger (0.09 Ma). Remnants of silicic magma bodies under Mt. Konocti may be in the latter stages of cooling, whereas a magma body centered under Borax Lake may be in the early stages of development. The existence of an upper crustal silicic magma body of under Borax Lake has yet to be demonstrated by passive geophysics, however, subsurface temperatures in the area as high (> 200{degrees}C at 2000 m) as those beneath the Mt. Konocti area. Based on petrologic considerations alone, the Mt. Konocti-Borax Lake area appears to be the most logical choice for HDR geothermal development in the region.« less

  6. Integrated exploration for low-temperature geothermal resources in the Honey Lake basin, California

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schimschal, U.

    An integrated exploration study is presented to locate low-temperature geothermal reservoirs in the Honey Lake area of northern California. Regional studies to locate the geothermal resources included gravity, infrared, water-temperature, and water-quality analyses. Five anomalies were mapped from resistivity surveys. Additional study of three anomalies by temperature-gradient and seismic methods was undertaken to define structure and potential of the geothermal resource. The gravity data show a graben structure in the area. Seismic reflection data, indicate faults associated with surface-resistivity and temperature-gradient data. The data support the interpretation that the shallow reservoirs are replenished along the fault zones by deeply circulatingmore » heated meteoric waters.« less

  7. DINKEY LAKES ROADLESS AREA, CALIFORNIA.

    USGS Publications Warehouse

    Dodge, F.C.W.; Federspiel, F.E.

    1984-01-01

    The Dinkey Lakes Roadless Area occupies an area of about 184 sq mi on the western slope of the Sierra Nevada, California. The results of a mineral survey show that parts of the area have substantiated resource potential for tungsten and marble and probable resource potential for quartz crystal gemstones. A probable resource potential for geothermal energy exists in one small area. No potential for other metallic mineral or energy resources was identified in this study.

  8. Marine and land active-source seismic imaging of mid-Miocene to Holocene-aged faulting near geothermal prospects at Pyramid Lake, Nevada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eisses, A.; Kell, A.; Kent, G.

    Amy Eisses, Annie Kell, Graham Kent, Neal Driscoll, Robert Karlin, Rob Baskin, John Louie, and Satish Pullammanappallil, 2011, Marine and land active-source seismic imaging of mid-Miocene to Holocene-aged faulting near geothermal prospects at Pyramid Lake, Nevada: Geothermal Resources Council Transactions, 35, 7 pp. Preprint at http://crack.seismo.unr.edu/geothermal/Eisses-GRCpaper-sm.pdf The Pyramid Lake fault zone lies within a vitally important area of the northern Walker Lane where not only can transtension can be studied through a complex arrangement of strike-slip and normal faults but also geothermal activity can be examined in the extensional regime for productivity. This study used advanced and economical seismic methodsmore » in attempt to develop the Paiute Tribe’s geothermal reservoir and to expand upon the tectonics and earthquake hazard knowledge of the area. 500 line-kilometers of marine CHIRP data were collected on Pyramid Lake combined with 27 kilometers of vibrator seismic on-land data from the northwest side of the basin were collected in 2010 that highlighted two distinct phases of faulting. Preliminary results suggest that the geothermal fluids in the area are controlled by the late Pleistoceneto Holocene-aged faults and not through the mid-Miocene-aged conduits as originally hypothesized.« less

  9. DOLUS LAKES ROADLESS AREA, MONTANA.

    USGS Publications Warehouse

    Elliott, James E.; Avery, Dale W.

    1984-01-01

    A mineral survey of the Dolus Lakes Roadless Area in southwestern Montana, was conducted. Much of the roadless area has probable and substantiated potential for resources of gold, silver, molybdenum, and tungsten. The nature of the geologic terrain indicates that there is little promise for the occurrence of coal, oil, gas, or geothermal resources. Detailed geologic and geochemical studies are suggested to delineate exploration targets that could be tested by drilling.

  10. Gravity Survey on the Glass Buttes Geothermal Exploration Project Lake County, Oregon

    DOE Data Explorer

    John Akerley

    2011-10-12

    This report covers data acquisition, instrumentation and processing of a gravity survey performed on the Glass Buttes Geothermal Exploration Project, located in Lake County, Oregon for ORMAT Technologies Inc. The survey was conducted during 21 June 2010 to 26 June 2010. The survey area is located in T23S, R21-23E and lies within the Glass Buttes, Hat Butte, and Potato Lake, Oregon 1:24,000 topographic sheets. A total of 180 gravity stations were acquired along five profile lines.

  11. 3D Model of the San Emidio Geothermal Area

    DOE Data Explorer

    James E. Faulds

    2013-12-31

    The San Emidio geothermal system is characterized by a left-step in a west-dipping normal fault system that bounds the western side of the Lake Range. The 3D geologic model consists of 5 geologic units and 55 faults. Overlying Jurrassic-Triassic metasedimentary basement is a ~500 m-1000 m thick section of the Miocene lower Pyramid sequence, pre- syn-extensional Quaternary sedimentary rocks and post-extensional Quaternary rocks. 15-30º eastward dip of the stratigraphy is controlled by the predominant west-dipping fault set. Both geothermal production and injection are concentrated north of the step over in an area of closely spaced west dipping normal faults.

  12. Geothermal activity and hydrothermal mineral deposits at southern Lake Bogoria, Kenya Rift Valley: Impact of lake level changes

    NASA Astrophysics Data System (ADS)

    Renaut, Robin W.; Owen, R. Bernhart; Ego, John K.

    2017-05-01

    Lake Bogoria, a saline alkaline closed-lake in a drainage basin of Neogene volcanic rocks in the central Kenya Rift, is fed partly by ∼200 hot alkaline springs located in three groups along its margins. Hot springs along the midwest shoreline (Loburu, Chemurkeu) and their travertine deposits have been studied, but little is known about the geothermal activity at southern Lake Bogoria. Observations, field measurements and analyses (geochemical and mineralogical) of the spring waters and deposits, spanning three decades, show that the southern spring waters are more saline, the hydrothermal alteration there is more intense, and that most hot spring deposits are siliceous. Geothermal activity at southern Lake Bogoria (Ng'wasis, Koibobei, Losaramat) includes littoral boiling springs and geysers, with fumaroles at slightly higher elevations. Modern spring deposits are ephemeral sodium carbonates, opal-A crusts and silica gels. Local fossil spring deposits include diatomaceous silica-cemented conglomerates that formed subaqueously when the lake was then dilute and higher than today, and outlying calcite tufa deposits. In contrast, mineral deposits around neighbouring fumarole vents and sites of hydrothermal alteration include clays (kaolinite), sulfate minerals (jarosite, alunite), and Fe-oxyhydroxides linked to rising acidic fluids. When lake level falls, the zone of acidity moves downwards and may overprint older alkaline spring deposits. In contrast, rising lake level leads to lake water dilution and vents in the lower parts of the acidic zone may become dilute alkaline springs. The new evidence at Lake Bogoria shows the potential for using the mineralogy of geothermal sediments to indicate former changes in lake level.

  13. Effects of geothermal activity and primary production on molybdenum isotopes: Lake Mývatn, Iceland

    NASA Astrophysics Data System (ADS)

    Neely, R.; Gíslason, S. R.; Ólafsson, M.; Pearce, C. R.; Torssander, P.; Eiríksdóttir, E. S.; Burton, K. W.

    2016-12-01

    Molybdenum (Mo) is highly sensitive to oxidation state and its isotopes are used as a proxy for redox conditions in the palaeoenvironent, particularly in the oceans. Geothermal systems play an important role in element cycles, comprising 10% of the Mo flux to the oceans and the dominant mechanism for Mo ore formation in porphyry deposits. Currently, little is known about Mo isotopes in either geothermal or groundwaters or how these systems may affect global mass balance. This study takes the Lake Mývatn area as a natural laboratory to study both geothermally affected and unaffected groundwaters, along with seasonal variations in a lacustrine environment. We present a comprehensive elemental and Mo isotope study of two groundwater systems from a basaltic terrain in North Iceland. The waters are of meteoric origin, range in sampling temperature from 2-93°C and in Mo isotope composition (δ98MoNIST) from -0.40 to 1.81‰. The Mo isotopic signature of the waters is largely controlled by mixing between cold groundwaters (isotopically light) and a geothermal end member (isotopically heavy). One of these groundwater systems forms the only input into Lake Mývatn: one of the most productive lakes in the northern hemisphere. Here we also present a time series from the Laxá River, which is the only outflow from the lake. Whilst seasonal variations in Mo isotopes are small (from δ98MoNIST 0.1 to 0.3‰) they positively correlate (R2 = 0.8) with variations in δ34S (from δ43S 1.7 to 4.6‰) with a shift to a heavier isotope peaks in late summer (September). This increase in δ98Mo coincides with a documented cyanobacteria bloom in late July to early September, known to preferentially use light isotopes.

  14. Geothermal areas in Pakistan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shuja, T.A.

    1986-01-01

    In this paper an attempt has been made to correlate the tectonic and geologic features with surface manifestations of geothermal activity in Pakistan to delineate prospective areas for exploration and development of geothermal energy. Underthrusting of the Arabian plate beneath the Eurasian plate has resulted in the formation of Chagai volcanic arc which extends into Iran. Quaternary volcanics in this environment, along with the presence of thermal springs, is an important geotectonic feature revealing the possible existence of geothermal fields. Geothermal activity in the northern areas of Pakistan, as evidenced by thermal springs, is the likely result of collision andmore » underthrusting of the Indian plate beneath the Eurasian plate. Numerous hot springs are found along the Main Mantle thrust and the Main Karakorum thrust in Chilas and Hunza areas respectively. The concentration of hot springs in Sind Province is also indicative of geothermal activity. A string of thermal seepages and springs following the alignment of the Syntaxial Bend in Punjab Province is also noteworthy from the geothermal viewpoint. In Baluchistan Province (southwest Pakistan), Hamun-e-Mushkel, a graben structure, also shows geothermal prospects on the basis of aeromagnetic studies.« less

  15. Value distribution assessment of geothermal development in Lake County, CA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Churchman, C.W.; Nelson, H.G.; Eacret, K.

    1977-10-01

    A value distribution assessment is defined as the determination of the distribution of benefits and costs of a proposed or actual development, with the intent of comparing such a development with alternative plans. Included are not only the social and economic effects, but also people's perceptions of their roles and how they are affected by the proposed or actual development. Discussion is presented under the following section headings: on morality and ethics; the vanishing community; case study of pre-development planning--Lake County; methodology for research; Lake County geothermal energy resource; decision making; Planning Commission hearing; communication examples; benefit tracing; response tomore » issues raised by the report of the State Geothermal Task Force; and, conclusions and recommendations. (JGB)« less

  16. Thermal modeling of step-out targets at the Soda Lake geothermal field, Churchill County, Nevada

    NASA Astrophysics Data System (ADS)

    Dingwall, Ryan Kenneth

    Temperature data at the Soda Lake geothermal field in the southeastern Carson Sink, Nevada, highlight an intense thermal anomaly. The geothermal field produces roughly 11 MWe from two power producing facilities which are rated to 23 MWe. The low output is attributed to the inability to locate and produce sufficient volumes of fluid at adequate temperature. Additionally, the current producing area has experienced declining production temperatures over its 40 year history. Two step-out targets adjacent to the main field have been identified that have the potential to increase production and extend the life of the field. Though shallow temperatures in the two subsidiary areas are significantly less than those found within the main anomaly, measurements in deeper wells (>1,000 m) show that temperatures viable for utilization are present. High-pass filtering of the available complete Bouguer gravity data indicates that geothermal flow is present within the shallow sediments of the two subsidiary areas. Significant faulting is observed in the seismic data in both of the subsidiary areas. These structures are highlighted in the seismic similarity attribute calculated as part of this study. One possible conceptual model for the geothermal system(s) at the step-out targets indicated upflow along these faults from depth. In order to test this hypothesis, three-dimensional computer models were constructed in order to observe the temperatures that would result from geothermal flow along the observed fault planes. Results indicate that the observed faults are viable hosts for the geothermal system(s) in the step-out areas. Subsequently, these faults are proposed as targets for future exploration focus and step-out drilling.

  17. Honey Lake Geothermal Project, Lassen County, California

    NASA Astrophysics Data System (ADS)

    1984-11-01

    The drilling, completion, and testing of deep well WEN-2 for a hybrid electric power project which will use the area's moderate temperature geothermal fluids and locally procured wood fuel is reported. The project is located within the Wendel-Amedee Known Geothermal Resource Area.

  18. Geothermal Flux, Basal Melt Rates, and Subglacial Lakes in Central East Antarctica

    NASA Astrophysics Data System (ADS)

    Carter, S. P.; Blankenship, D. D.; Morse, D. L.

    2002-12-01

    The lakes beneath the East Antarctic ice sheet represent a unique environment on Earth, entirely untouched by human interference. Life forms which survive in this cold, lightless, high pressure environment may resemble the life forms which survived through "snowball earth" and evolved into the life forms we know today (Kirchvink, 2000). Recent airborne radar surveys over Dome C and the South Pole regions allow us to assess where these lakes are most likely to exist and infer melting and freezing rates at base of the ice sheet. Lakes appear as strong, flat basal reflectors in airborne radar sounding data. In order to determine the absolute strength of the reflector it is important to accurately estimate signal loss due to absorption by the ice. As this quantity is temperature sensitive, especially in regions where liquid water is likely to exist, we have developed a one dimensional heat transfer model, incorporating surface temperature, accumulation, ice sheet thickness, and geothermal flux. Of the four quantities used for our temperature model, geothermal flux has usually proven to be the most difficult to asses, due to logistical difficulties. A technique developed by Fahnestock et al 2001 is showing promise for inferring geothermal flux, with airborne radar data. This technique assumes that internal reflectors, which result from varying electrical properties within the ice column, can be approximated as constant time horizons. Using ice core data from our study area, we can place dates upon these internal layers and develop an age versus depth relationship for the surveyed region, with margin of error of +- 50 m for each selected layer. Knowing this relationship allows us to infer the vertical strain response of the ice to the stress of vertical loading by snow accumulation. When ice is frozen to the bed the deeper ice will accommodate the increased stress of by deforming and thinning (Patterson 1994). This thinning of deeper layers occurs throughout most of our

  19. Environmental Assessment Lakeview Geothermal Project

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Treis, Tania

    2012-04-30

    The Town of Lakeview is proposing to construct and operate a geothermal direct use district heating system in Lakeview, Oregon. The proposed project would be in Lake County, Oregon, within the Lakeview Known Geothermal Resources Area (KGRA). The proposed project includes the following elements: Drilling, testing, and completion of a new production well and geothermal water injection well; construction and operation of a geothermal production fluid pipeline from the well pad to various Town buildings (i.e., local schools, hospital, and Lake County Industrial Park) and back to a geothermal water injection well. This EA describes the proposed project, the alternativesmore » considered, and presents the environmental analysis pursuant to the National Environmental Policy Act. The project would not result in adverse effects to the environment with the implementation of environmental protection measures.« less

  20. Marine and land active-source seismic investigation of geothermal potential, tectonic structure, and earthquake hazards in Pyramid Lake, Nevada

    NASA Astrophysics Data System (ADS)

    Eisses, A.; Kell, A. M.; Kent, G.; Driscoll, N. W.; Karlin, R. E.; Baskin, R. L.; Louie, J. N.; Smith, K. D.; Pullammanappallil, S.

    2011-12-01

    Preliminary slip rates measured across the East Pyramid Lake fault, or the Lake Range fault, help provide new estimates of extension across the Pyramid Lake basin. Multiple stratigraphic horizons spanning 48 ka were tracked throughout the lake, with layer offsets measured across all significant faults in the basin. A chronstratigraphic framework acquired from four sediment cores allows slip rates of the Lake Range and other faults to be calculated accurately. This region of the northern Walker Lake, strategically placed between the right-lateral strike-slip faults of Honey and Eagle Lakes to the north, and the normal fault bounded basins to the southwest (e.g., Tahoe, Carson), is critical in understanding the underlying structural complexity that is not only necessary for geothermal exploration, but also earthquake hazard assessment due to the proximity of the Reno-Sparks metropolitan area. In addition, our seismic CHIRP imaging with submeter resolution allows the construction of the first fault map of Pyramid Lake. The Lake Range fault can be obviously traced west of Anahoe Island extending north along the east end of the lake in numerous CHIRP lines. Initial drafts of the fault map reveal active transtension through a series of numerous, small, northwest striking, oblique-slip faults in the north end of the lake. A previously field mapped northwest striking fault near Sutcliff can be extended into the west end of Pyramid Lake. This fault map, along with the calculated slip rate of the Lake Range, and potentially multiple other faults, gives a clearer picture into understanding the geothermal potential, tectonic regime and earthquake hazards in the Pyramid Lake basin and the northern Walker Lane. These new results have also been merged with seismicity maps, along with focal mechanisms for the larger events to begin to extend our fault map in depth.

  1. Near-Surface Geophysical Character of a Holocene Fault Carrying Geothermal Flow Near Pyramid Lake, Nevada

    NASA Astrophysics Data System (ADS)

    Dudley, C.; Dorsey, A.; Louie, J. N.; Schwering, P. C.; Pullammanappallil, S.

    2012-12-01

    preserved older tufa columns within the section. Near-surface Wenner arrays with a-spacings up to 30 m show a higher resistivity near the faults, and tufa, than away from the faults. Resistivity averages were 33 ± 17 ohm-m on the fault, 13 ± 3 ohm-m east of the fault, and 9 ± 3 ohm-m west of the fault. It is possible the geothermal waters are fresher than waters held in the lakebed clays. Water samples from more than 1 km depth in exploration wells had almost drinking-water quality. This higher resistivity of the waters carried by the fault zone, with perhaps a higher porosity and permeability along the fault, could explain the higher resistivity near the fault. Our work shows that there is no high-velocity, high-resistivity tufa along the faults below the surface, so we are unable to use buried tufa to locate faults with geothermal upwellings in this area. We can further hypothesize that as sedimentation buried the tufa during the Quaternary, warm geothermal waters re-dissolved it, and re-precipitated it only in the cold lake-bottom water.

  2. Geothermal space/water heating for City of Mammoth Lakes, California. Draft final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sims, A.V.; Racine, W.C.

    1977-09-01

    The results of a study to determine the technical, economic and environmental feasibility of geothermal district heating for Mammoth Lakes Village, California are presented. The geothermal district heating system selected is technically feasible and uses existing technology in its design and operation. During a preliminary environmental assessment, no potential adverse environmental impacts could be identified of sufficient consequence to preclude the construction and operation of the proposed district heating system. A follow-on program aimed at implementing district heating in Mammoth is outlined.

  3. Structural control on geothermal circulation in the Tocomar geothermal volcanic area (Puna plateau, Argentina)

    NASA Astrophysics Data System (ADS)

    Giordano, Guido

    2016-04-01

    The reconstruction of the stratigraphical-structural framework and the hydrogeology of geothermal areas is fundamental for understanding the relationships between cap rocks, reservoir and circulation of geothermal fluids and for planning the exploitation of the field. The Tocomar geothermal volcanic area (Puna plateau, Central Andes, NW Argentina) has a high geothermal potential. It is crossed by the active NW-SE trans-Andean tectonic lineament known as the Calama-Olacapato-Toro (COT) fault system, which favours a high secondary permeability testified by the presence of numerous thermal springs. This study presents new stratigraphic, structural, volcanological, geochemical and hydrogeological data on the geothermal field. Our data suggest that the main geothermal reservoir is located within or below the Pre-Palaeozoic-Ordovician basement units, characterised by unevenly distributed secondary permeability. The reservoir is recharged by infiltration in the ridges above 4500 m a.s.l., where basement rocks are in outcrop. Below 4500 m a.s.l., the reservoir is covered by the low permeable Miocene-Quaternary units that allow a poor circulation of shallow groundwater. Geothermal fluids upwell in areas with more intense fracturing, especially where main regional structures, particularly NW-SE COT-parallel lineaments, intersect with secondary structures, such as at the Tocomar field.

  4. Geological investigation of the Socorro geothermal area. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chapin, C.E.; Sanford, A.R.; White, D.W.

    1979-05-01

    The results of a comprehensive geological and geochemical study of the Socorro geothermal area are presented. The following are discussed: geologic setting, structural controls, stratigraphic controls, an ancient geothermal system, modern magma bodies, geothermal potential of the Socorro area, and the Socorro transverse shear zone. (MHR)

  5. Fault and joint geometry at Raft River Geothermal Area, Idaho

    NASA Astrophysics Data System (ADS)

    Guth, L. R.; Bruhn, R. L.; Beck, S. L.

    1981-07-01

    Raft River geothermal reservoir is formed by fractures in sedimentary strata of the Miocene and Pliocene salt lake formation. The fracturing is most intense at the base of the salt lake formation, along a decollement that dips eastward at less than 50 on top of metamorphosed precambrian and lower paleozoic rocks. Core taken from less than 200 m above the decollement contains two sets of normal faults. The major set of faults dips between 500 and 700. These faults occur as conjugate pairs that are bisected by vertical extension fractures. The second set of faults dips 100 to 200 and may parallel part of the basal decollement or reflect the presence of listric normal faults in the upper plate. Surface joints form two suborthogonal sets that dip vertically. East-northeast-striking joints are most frequent on the limbs of the Jim Sage anticline, a large fold that is associated with the geothermal field.

  6. Hydrothermal and tectonic activity in northern Yellowstone Lake, Wyoming

    USGS Publications Warehouse

    Johnson, S.Y.; Stephenson, W.J.; Morgan, L.A.; Shanks, Wayne C.; Pierce, K.L.

    2003-01-01

    Yellowstone National Park is the site of one of the world's largest calderas. The abundance of geothermal and tectonic activity in and around the caldera, including historic uplift and subsidence, makes it necessary to understand active geologic processes and their associated hazards. To that end, we here use an extensive grid of high-resolution seismic reflection profiles (???450 km) to document hydrothermal and tectonic features and deposits in northern Yellowstone Lake. Sublacustrine geothermal features in northern Yellowstone Lake include two of the largest known hydrothermal explosion craters, Mary Bay and Elliott's. Mary Bay explosion breccia is distributed uniformly around the crater, whereas Elliott's crater breccia has an asymmetric distribution and forms a distinctive, ???2-km-long, hummocky lobe on the lake floor. Hydrothermal vents and low-relief domes are abundant on the lake floor; their greatest abundance is in and near explosion craters and along linear fissures. Domed areas on the lake floor that are relatively unbreached (by vents) are considered the most likely sites of future large hydrothermal explosions. Four submerged shoreline terraces along the margins of northern Yellowstone Lake add to the Holocene record or postglacial lake-level fluctuations attributed to "heavy breathing" of the Yellowstone magma reservoir and associated geothermal system. The Lake Hotel fault cuts through northwestern Yellowstone Lake and represents part of a 25-km-long distributed extensional deformation zone. Three postglacial ruptures indicate a slip rate of ???0.27 to 0.34 mm/yr. The largest (3.0 m slip) and most recent event occurred in the past ???2100 yr. Although high heat flow in the crust limits the rupture area of this fault zone, future earthquakes of magnitude ???5.3 to 6.5 are possible. Earthquakes and hydrothermal explosions have probably triggered landslides, common features around the lake margins. Few high-resolution seismic reflection surveys have

  7. Geothermal Gases--Community Experiences, Perceptions, and Exposures in Northern California.

    PubMed

    Chiu, Cindy H; Lozier, Matthew J; Bayleyegn, Tesfaye; Tait, Karen; Barreau, Tracy; Copan, Lori; Roisman, Rachel; Jackson, Rebecca; Smorodinsky, Svetlana; Kreutzer, Richard A; Yip, Fuyuen; Wolkin, Amy

    2015-12-01

    Lake County, California, is in a high geothermal-activity area. Over the past 30 years, the city of Clearlake has reported health effects and building evacuations related to geothermal venting. Previous investigations in Clearlake revealed hydrogen sulfide at levels known to cause health effects and methane at levels that can cause explosion risks. The authors conducted an investigation in multiple cities and towns in Lake County to understand better the risk of geothermal venting to the community. They conducted household surveys and outdoor air sampling of hydrogen sulfide and methane and found community members were aware of geothermal venting and some expressed concerns. The authors did not, however, find hydrogen sulfide above the California Environmental Protection Agency air quality standard of 30 parts per billion over one hour or methane above explosive thresholds. The authors recommend improving risk communication, continuing to monitor geothermal gas effects on the community, and using community reports and complaints to monitor and document geothermal venting incidents.

  8. Geothermal constraints on enrichment of boron and lithium in salt lakes: An example from a river-salt lake system on the northern slope of the eastern Kunlun Mountains, China

    NASA Astrophysics Data System (ADS)

    Tan, Hongbing; Chen, Jun; Rao, Wenbo; Zhang, Wenjie; Zhou, Huifang

    2012-06-01

    Some rivers on the northern slope of the eastern Kunlun Mountains in the Qaidam Basin, China, show very high concentrations of boron and lithium. Correspondingly, the salt lakes fed by these rivers show an unusual enrichment of boron and lithium, and become an important economic resource. The origin of boron and lithium has long been debated. The aim of this study is to analyze the water chemistry and hydrogen and oxygen isotopic composition of river water to understand the unusual enrichment of boron and lithium in the salt lakes of the Qaidam Basin. Oxygen and hydrogen isotope data show that the source of river water in the winter and summer originates from the Kunlun Mountain ice and snow melt water, respectively. The water chemistry shows that boron and lithium contents are high but little variable with seasons in the Nalenggele River and Wutumeiren River waters. By contrast, other rivers have much lower lithium and boron contents. Moreover, the contents of B3+ and Li+ in the river loads or bed sands show little difference amongst the rivers. This indicates that removal by adsorption or input by surface rock weathering is not the main controlling factor of the B3+ and Li+ variation in the rivers. Rivers with high B3+ and Li+ content are chemically similar to geothermal waters in the Tibetan Plateau. In addition, the source area of the Nalenggele River is located in a collision zone of the Kunlun Mountains and Altun Mountains. Large and deep faults can serve as conduits for geothermal fluids. Thus, deep geothermal waters in the source area can easily migrate to the surface and discharge as springs feeding the rivers. They are an important source of B3+ and Li+ to the rivers. The abnormally high contents of B3+ and Li+ in the Nalenggele and Wutumeiren Rivers also suggest that the geothermal source area may be a future target for boron and lithium resources.

  9. Structural control on geothermal circulation in the Cerro Tuzgle-Tocomar geothermal volcanic area (Puna plateau, Argentina)

    NASA Astrophysics Data System (ADS)

    Giordano, Guido; Pinton, Annamaria; Cianfarra, Paola; Baez, Walter; Chiodi, Agostina; Viramonte, José; Norini, Gianluca; Groppelli, Gianluca

    2013-01-01

    The reconstruction of the stratigraphical-structural framework and the hydrogeology of geothermal areas is fundamental for understanding the relationships between cap rocks, reservoir and circulation of geothermal fluids and for planning the exploitation of the field. The Cerro Tuzgle-Tocomar geothermal volcanic area (Puna plateau, Central Andes, NW Argentina) has a high geothermal potential. It is crossed by the active NW-SE trans-Andean tectonic lineament known as the Calama-Olacapato-Toro (COT) fault system, which favours a high secondary permeability testified by the presence of numerous springs. This study presents new stratigraphic and hydrogeological data on the geothermal field, together with the analysis from remote sensed image analysis of morphostructural evidences associated with the structural framework and active tectonics. Our data suggest that the main geothermal reservoir is located within or below the Pre-Palaeozoic-Ordovician basement units, characterised by unevenly distributed secondary permeability. The reservoir is recharged by infiltration in the ridges above 4500 m a.s.l., where basement rocks are in outcrop. Below 4500 m a.s.l., the reservoir is covered by the low permeable Miocene-Quaternary units that allow a poor circulation of shallow groundwater. Geothermal fluids upwell in areas with more intense fracturing, especially where main regional structures, particularly NW-SE COT-parallel lineaments, intersect with secondary structures, such as at the Tocomar field. Away from the main tectonic features, such as at the Cerro Tuzgle field, the less developed network of faults and fractures allows only a moderate upwelling of geothermal fluids and a mixing between hot and shallow cold waters. The integration of field-based and remote-sensing analyses at the Cerro Tuzgle-Tocomar area proved to be effective in approaching the prospection of remote geothermal fields, and in defining the conceptual model for geothermal circulation.

  10. The Coso geothermal area: A laboratory for advanced MEQ studies for geothermal monitoring

    USGS Publications Warehouse

    Julian, B.R.; Foulger, G.R.; Richards-Dinger, K.

    2004-01-01

    The permanent 16-station network of three-component digital seismometers at the Coso geothermal area, California, supplemented by 14 temporary instruments deployed in connection with the DOE Enhanced Geothermal Systems (EGS) Project, provides high-quality microearthquake (MEQ) recordings that are well suited to monitoring a producing geothermal area. We are currently using these data to investigate structure and active processes within the geothermal reservoir by applying three advanced methods: a) high-precision MEQ hypocenter location; b) time-dependent tomography; c) complete (moment tensor) MEQ source mechanism determination. Preliminary results to date resolve seismogenic structures in the producing field more clearly than is possible with conventional earthquake-location techniques. A shallow part of the producing field shows clear changes in the ratio of the seismic wave speeds, Vp/V s, between 1996 and 2002, which are probably related to physical changes in the reservoir caused by fluid extraction.

  11. Strategies for steam handling and H2S abatement at geothermal power plants in the geysers area of Northern California

    NASA Astrophysics Data System (ADS)

    Morris, W. F.; Stephens, F. B.

    1981-08-01

    Strict limitations on the emission of H2S from new geothermal power plants in The Geysers area of northern California were imposed by Lake and Northern Sonoma County Air Pollution Control Districts. Lake County, under new source review rules, stipulated that specific technologies should be utilized to limit H2S emissions to 5 lb/h as a condition for determination of compliance. The status of these technologies as well as other ongoing technology development efforts to conserve steam and abate H2S are evaluated.

  12. Geochemical evolution of groundwater in the Mud Lake area, eastern Idaho, USA

    USGS Publications Warehouse

    Rattray, Gordon W.

    2015-01-01

    Groundwater with elevated dissolved-solids concentrations—containing large concentrations of chloride, sodium, sulfate, and calcium—is present in the Mud Lake area of Eastern Idaho. The source of these solutes is unknown; however, an understanding of the geochemical sources and processes controlling their presence in groundwater in the Mud Lake area is needed to better understand the geochemical sources and processes controlling the water quality of groundwater at the Idaho National Laboratory. The geochemical sources and processes controlling the water quality of groundwater in the Mud Lake area were determined by investigating the geology, hydrology, land use, and groundwater geochemistry in the Mud Lake area, proposing sources for solutes, and testing the proposed sources through geochemical modeling with PHREEQC. Modeling indicated that sources of water to the eastern Snake River Plain aquifer were groundwater from the Beaverhead Mountains and the Camas Creek drainage basin; surface water from Medicine Lodge and Camas Creeks, Mud Lake, and irrigation water; and upward flow of geothermal water from beneath the aquifer. Mixing of groundwater with surface water or other groundwater occurred throughout the aquifer. Carbonate reactions, silicate weathering, and dissolution of evaporite minerals and fertilizer explain most of the changes in chemistry in the aquifer. Redox reactions, cation exchange, and evaporation were locally important. The source of large concentrations of chloride, sodium, sulfate, and calcium was evaporite deposits in the unsaturated zone associated with Pleistocene Lake Terreton. Large amounts of chloride, sodium, sulfate, and calcium are added to groundwater from irrigation water infiltrating through lake bed sediments containing evaporite deposits and the resultant dissolution of gypsum, halite, sylvite, and bischofite.

  13. Structural controls on geothermal circulation in Surprise Valley, California: A re-evaluation of the Lake City fault zone

    USGS Publications Warehouse

    Anne E. Egger,; Glen, Jonathan; McPhee, Darcy K.

    2014-01-01

    Faults and fractures play an important role in the circulation of geothermal fluids in the crust, and the nature of that role varies according to structural setting and state of stress. As a result, detailed geologic and geophysical mapping that relates thermal springs to known structural features is essential to modeling geothermal systems. Published maps of Surprise Valley in northeastern California suggest that the “Lake City fault” or “Lake City fault zone” is a significant structural feature, cutting obliquely across the basin and connecting thermal springs across the valley. Newly acquired geophysical data (audio-magnetotelluric, gravity, and magnetic), combined with existing geochemical and geological data, suggest otherwise. We examine potential field profiles and resistivity models that cross the mapped Lake City fault zone. While there are numerous geophysical anomalies that suggest subsurface structures, they mostly do not coincide with the mapped traces of the Lake City fault zone, nor do they show a consistent signature in gravity, magnetics, or resistivities that would suggest a through-going fault that would promote connectivity through lateral fluid flow. Instead of a single, continuous fault, we propose the presence of a deformation zone associated with the growth of the range-front Surprise Valley fault. The implication for geothermal circulation is that this is a zone of enhanced porosity but lacks length-wise connectivity that could conduct fluids across the valley. Thermal fluid circulation is most likely controlled primarily by interactions between N-S–trending normal faults.

  14. The detection of geothermal areas from Skylab thermal data

    NASA Technical Reports Server (NTRS)

    Siegal, B. S.; Kahle, A. B.; Goetz, A. F. H.; Gillespie, A. R.; Abrams, M. J.; Pohn, H. A.

    1975-01-01

    Skylab-4 X-5 thermal data of the geysers area was analyzed to determine the feasibility of using midday Skylab images to detect geothermal areas. The hottest ground areas indicated on the Skylab image corresponded to south-facing barren or sparsely vegetated slopes. A geothermal area approximately 15 by 30 m coincided with one of the hottest areas indicated by Skylab. This area could not be unambiguously distinguished from the other areas which are believed to be hotter than their surroundings as a result of their topography, and micrometeorological conditions. A simple modification of a previous thermal model was performed and the predicted temperatures for the hottest slopes using representative values was in general agreement with the observed data. It is concluded that data from a single midday Skylab pass cannot be used to locate geothermal areas.

  15. Rock geochemistry related to mineralization processes in geothermal areas

    NASA Astrophysics Data System (ADS)

    Kausar, A. Al; Indarto, S.; Setiawan, I.

    2018-02-01

    Abundant geothermal systems in Indonesia suggest high heat and mass transfer associated with recent or paleovolcanic arcs. In the active geothermal system, the upflow of mixed fluid between late stage hydrothermal and meteoric water might contain mass of minerals associated with epithermal mineralisation process as exemplified at Lihir gold mine in Papua New Guinea. In Indonesia, there is a lack of study related to the precious metals occurrence within active geothermal area. Therefore, in this paper, we investigate the possibility of mineralization process in active geothermal area of Guci, Central Java by using geochemical analysis. There are a lot of conducted geochemical analysis of water, soil and gas by mapping the temperature, pH, Hg and CO2 distribution, and estimating subsurface temperature based on geothermometry approach. Then we also apply rock geochemistry to find minerals that indicate the presence of mineralization. The result from selected geothermal area shows the presence of pyrite and chalcopyrite minerals on the laharic breccias at Kali Putih, Sudikampir. Mineralization is formed within host rock and the veins are associated with gold polymetallic mineralization.

  16. Detectability of geothermal areas using Skylab X-5 data

    NASA Technical Reports Server (NTRS)

    Siegal, B. S.; Kahle, A. B.; Goetz, A. F. H.; Gillespie, A. R.; Abrams, M. J.

    1975-01-01

    The results are presented of a study which was undertaken to determine if data from a single near-noon pass of Skylab could be used to detect geothermal areas. The size and temperature requirements for a geothermally heated area to be seen by Skylab S-192 MSS X-5 thermal sensor were calculated. This sensor obtained thermal data with the highest spatial resolution of any nonmilitary satellite system. Only very large hot areas could be expected to be unambiguously recognized with a single data set from this instrument. The study area chosen was The Geysers geothermal field in Sonoma County, California, the only geothermal area of significant size scanned by Skylab. Unfortunately, 95% of the Skylab thermal channel data was acquired within 3 hours of local noon. For The Geysers area only daytime X-5 data were available. An analysis of the thermal channel data (10.2 to 12.5 um) revealed that ground temperatures determined by Skylab were normally distributed. No anomalous hot spots were apparent. Computer enhancement techniques were used to delineate the hottest 100 and 300 ground areas (pixel, 75 m by 75 m) within the study region. It was found that the Skylab MSS with the X-5 thermal detector does not have sufficient spatial resolution to locate unambiguously from daytime data any but the largest and hottest convectively created geothermal features, which in general are prominent enough to have been previously recognized.

  17. Schlumberger soundings near Medicine Lake, California

    USGS Publications Warehouse

    Zohdy, A.A.R.; Bisdorf, R.J.

    1990-01-01

    The use of direct current resistivity soundings to explore the geothermal potential of the Medicine Lake area in northern California proved to be challenging because of high contact resistances and winding roads. Deep Schlumberger soundings were made by expanding current electrode spacings along the winding roads. Corrected sounding data were interpreted using an automatic interpretation method. Forty-two maps of interpreted resistivity were calculated for depths extending from 20 to 1000 m. Computer animation of these 42 maps revealed that: 1) certain subtle anomalies migrate laterallly with depth and can be traced to their origin, 2) an extensive volume of low-resistivity material underlies the survey area, and 3) the three areas (east of Bullseye Lake, southwest of Glass Mountain, and northwest of Medicine Lake) may be favorable geothermal targets. Six interpreted resistivity maps and three cross-sections illustrate the above findings. -from Authors

  18. Geology and geothermal potential of the tecuamburro volcano area, Guatemala

    USGS Publications Warehouse

    Duffield, W.A.; Heiken, G.H.; Wohletz, K.H.; Maassen, L.W.; Dengo, G.; McKee, E.H.; Castaneda, O.

    1992-01-01

    Tecuamburro, an andesitic stratovolcano in southeastern Guatemala, is within the chain of active volcanoes of Central America. Though Tecuamburro has no record of historic eruptions, radiocarbon ages indicate that eruption of this and three other adjacent volcanoes occurred within the past 38,300 years. The youngest eruption produced a dacite dome. Moreover, powerful steam explosions formed a 250 m wide crater about 2900 years ago near the base of this dome. The phreatic crater contains a pH-3 thermal lake. Fumaroles are common along the lake shore, and several other fumaroles are located nearby. Neutral-chloride hot springs are at lower elevations a few kilometers away. All thermal manifestations are within an area of about 400 km2 roughly centered on Tecuamburro Volcano. Thermal implications of the volume, age, and composition of the post-38.3 ka volcanic rocks suggest that magma, or recently solidified hot plutons, or both are in the crust beneath these lavas. Chemical geothermometry carried out by other workers suggests that a hydrothermal-convection system is centered over this crustal heat source. Maximum temperatures of about 300??C are calculated for samples collected in the area of youngest volcanism, whereas samples from outlying thermal manifestations yield calculated temperatures <- 165??C. An 808 m deep drill hole completed in 1990 to partly test the geothermal model developed from surface studies attained a maximum temperature of almost 240??C. Thus, the possibility of a commercial-grade hydrothermal resource in the area seems high. ?? 1992.

  19. Geothermal Potential Analysis Using Landsat 8 and Sentinel 2 (Case Study: Mount Ijen)

    NASA Astrophysics Data System (ADS)

    Sukojo, B. M.; Mardiana, R.

    2017-12-01

    Geothermal energy is also a heat energy contained in the earth’s internal. Indonesia has a total geothermal potential of around 27 GWe. The government is eager for the development of geothermal in Indonesia can run well so that geothermal can act as one of the pillars of national energy. However, the geothermal potential has not been fully utilized. One of the geothermal potention is Mount Ijen. Mount Ijen is a strato volcano that has a crater lake with a depth of about 190 m and has a very high degree of acidity and the volume of lake water is very large. With the abundance of potential geothermal potential in Indonesia, it is necessary to have an activity in the form of integrated geoscience studies to be able to maximize the potential content that exists in a geothermal area. One of the studies conducted is to do potential mapping. This research performs image data processing of Landsat 8, Sentinel 2, RBI Map, and preliminary survey data. This research carried out the Vegetation Index, surface temperature and altitude. The equipment used in this research includes image processing software, number processing software, GPS Handheld and Laptop. Surface Temperatures in the Mount Ijen have anomalies with large temperatures ranging between 18° C to 38° C. The best correlation value of altitude and ground surface temperature is -0.89 ie the correlation of January surface temperature. While the correlation value of Landsat 8 and Sentinel 2 vegetation index was 0.81. The land cover confidence matrix scored 80%. Land cover in the research area is dominated by forests by 35% of the research area. There is a potential area of geothermal potential is very high on Mount Ijen with an area of 39.43 hectares located in Wongsorejo District and adjacent to District Sempol.

  20. Marine and land active-source seismic imaging of mid-Miocene to Holocene-aged faulting near geothermal prospects at Pyramid Lake, Nevada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eisses, A.; Kell, A.; Kent, G.

    Amy Eisses, Annie Kell, Graham Kent, Neal Driscoll, Robert Karlin, Rob Baskin, John Louie, and Satish Pullammanappallil, 2011, Marine and land active-source seismic imaging of mid-Miocene to Holocene-aged faulting near geothermal prospects at Pyramid Lake, Nevada: presented at Geothermal Resources Council Annual Meeting, San Diego, Oct. 23-26.

  1. Near-surface geophysical characterization of Holocene faults conducive to geothermal flow near Pyramid Lake, Nevada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dudley, Colton; Dorsey, Alison; Louie, John

    Colton Dudley, Alison Dorsey, Paul Opdyke, Dustin Naphan, Marlon Ramos, John Louie, Paul Schwering, and Satish Pullammanappallil, 2013, Near-surface geophysical characterization of Holocene faults conducive to geothermal flow near Pyramid Lake, Nevada: presented at Amer. Assoc. Petroleum Geologists, Pacific Section Annual Meeting, Monterey, Calif., April 19-25.

  2. STRUCTURAL CONTROLS OF THE EMERSON PASS GEOTHERMAL SYSTEM, NORTHWESTERN NEVADA: CHARACTERIZATION OF A "BLIND" SYSTEM

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson, Ryan B; Faulds, James E

    The Pyramid Lake area is favorable for geothermal development due to the tectonic setting of the region. The Walker Lane belt, a dextral shear zone that accommodates ~20% relative motion between the Pacific and North American plates, terminates northwestward in northeast California. NW-directed dextral shear is transferred to WNW extension accommodated by N-to -NNE striking normal faults of the Basin and Range. As a consequence, enhanced dilation occurs on favorably oriented faults generating high geothermal potential in the northwestern Great Basin. The NW-striking right-lateral Pyramid Lake fault, a major structure of the northern Walker Lane, terminates at the southern endmore » of Pyramid Lake and transfers strain to the NNE-striking down to the west Lake Range fault, resulting in high geothermal potential. Known geothermal systems in the area have not been developed due to cultural considerations of the Pyramid Lake Paiute Tribe. Therefore, exploration has been focused on discovering blind geothermal systems elsewhere on the reservation by identifying structurally favorable settings and indicators of past geothermal activity. One promising area is the northeast end of Pyramid Lake, where a broad left step between the west-dipping range-bounding faults of the Lake and Fox Ranges has led to the formation of a broad, faulted relay ramp. Furthermore, tufa mounds, mineralized veins, and altered Miocene rocks occur proximal to a thermal anomaly discovered by a 2-m shallow temperature survey at the north end of the step-over in Emerson Pass. Detailed geologic mapping has revealed a system of mainly NNE-striking down to the west normal faults. However, there are three notable exceptions to this generality, including 1) a prominent NW-striking apparent right-lateral fault, 2) a NW-striking down to the south fault which juxtaposes the base of the mid-Miocene Pyramid sequence against younger late Tertiary sedimentary rocks, and 3) a NNE-striking down to the east normal

  3. Bruneau Known Geothermal Resource Area: an environmental analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Spencer, S.G.; Russell, B.F.

    1979-09-01

    The Bruneau Known Geothermal Resource Area (KGRA) is part of the Bruneau-Grandview thermal anomaly, the largest geothermal area in the western US. This part of Owyhee County is the driest part of Idaho. The KGRA is associated with the southern boundary fault zone of the Snake River Plain. Thermal water, produced from numerous artesian wells in the region, is supplied from two major aquifers. Ecological concerns include the threatened Astragalus mulfordiae and the numerous birds of prey nesting in the Snake River canyon northwest of the KGRA. Extensive geothermal development may strain the limited health care facilities in the county.more » Ethnographic information suggests that there is a high probability of prehistoric cultural materials being remnant in the Hot Spring locality.« less

  4. Hydrologic data and description of a hydrologic monitoring plan for Medicine Lake Volcano, California

    USGS Publications Warehouse

    Schneider, Tiffany Rae; McFarland, W.D.

    1996-01-01

    A hydrologic reconnaissance of the Medicine Lake Volcano area was done to collect data needed for the design of a hydrologic monitoring plan. The reconnaissance was completed during two field trips made in June and September 1992, during which geothermal and hydrologic features of public interest in the Medicine Lake area were identified. Selected wells, springs, and geothermal features were located and documented, and initial water-level, discharge, temperature, and specific-conductance measurements were made. Lakes in the study area also were surveyed during the September field trip. Temperature, specific- conductance, dissolved oxygen, and pH data were collected by using a multiparameter probe. The proposed monitoring plan includes measurement of water levels in wells, discharge from springs, and lake stage, as well as analysis of well-,spring-, and lake-water quality. In determining lake-water quality, data for both stratified and unstratified conditions would be considered. (Data for stratified conditions were collected during the reconnaissance phase of this project, but data for unstratified conditions were not.) In addition, lake stage also would be monitored. A geothermal feature near Medicine Lake is a "hot spot" from which hot gases discharge from two distinct vents. Gas chemistry and temperature would be monitored in one of these vents.

  5. Utah geothermal commercialization planning. Semi-annual progress report, January 1, 1979--June 30, 1979

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Green, S.; Wagstaff, L.W.

    1979-06-01

    The effects of the Utah geothermal planning project were concentrated on the Utah geothermal legislation, the Roosevelt Hot Springs time phased project plan and the Salt Lake County area development plan. Preliminary findings indicate a potential for heat pump utilization, based on market interest and the existence of suitable groundwater conditions. (MHR)

  6. The behaviour of antimony released from surface geothermal features in New Zealand

    NASA Astrophysics Data System (ADS)

    Wilson, Nathaniel; Webster-Brown, Jenny; Brown, Kevin

    2012-12-01

    Antimony-rich geothermal features in the Taupo Volcanic Zone (TVZ) of New Zealand's North Island drain directly into surface aquatic environments. The discharge from Champagne Pool, a mixed alkali-chloride/sulfate hot spring at Wai-O-Tapu Geothermal Field, contains up to 194 μg/L Sb. The discharge from Frying Pan Lake, a chloride-sulfate hot spring at Waimangu Geothermal Field, contains up to 21.5 μg/L Sb. At Champagne Pool, downstream concentrations of Sb show distinct diurnal variations, particularly in winter, when concentrations in the early morning were less than half those measured mid-afternoon. Changes in sulfide-sulfate equilibria and direct stibnite oxidation may explain this phenomenon. In the discharge from Frying Pan Lake, Sb exhibits little diurnal variation. Most (> 80%) of the dissolved Sb released from Champagne Pool is removed from solution at Alum Lake, an acid-sulfate hot pool containing elevated levels of dissolved sulfide. Therefore relatively little Sb is discharged into the freshwater drainage in the area. However, in the absence of a sulfide-rich feature at Waimangu, most of the Sb discharged from Frying Pan Lake remains dissolved, and is transported into the freshwater drainage system of Lake Rotomahana. The contrast in Sb behaviour between these two sites confirms the importance of dissolved sulfide and low (< 3) pH conditions in the precipitation and removal of dissolved Sb downstream of geothermal features. Otherwise, largely conservative behaviour can be expected.

  7. Preliminary study of Songa-Wayaua geothermal prospect area using volcanostratigraphy and remote sensing analysis

    NASA Astrophysics Data System (ADS)

    Asokawaty, Ribka; Nugroho, Indra; Satriana, Joshua; Hafidz, Muhamad; Suryantini

    2017-12-01

    Songa-Wayaua geothermal prospect area is located on Bacan Island, Northern Molluca Province. Geothermal systems in this area associated with three Quartenary volcanoes, such as Mt. Pele-pele, Mt. Lansa, and Mt. Bibinoi. Based on literature study, five surface manifestations such as hot springs and alteration occurred within this area. The active manifestations indicate that Songa-Wayaua area has potential geothermal resource. This study objective is to evaluate Songa-Wayaua geothermal system on preliminary study stage by using volcanostratigraphy and remote sensing analysis to delineate the boundary of geothermal system area. The result of this study showed that Songa-Wayaua prospect area has four heat sources potential (e.g. Pele-pele Hummock, Lansa Hummock, Songa Hummock, and Bibinoi Hummock), controlled by geological structure presented by Pele-pele Normal Fault, and had three places as the recharge and discharge area which are very fulfilling as a geothermal system.

  8. Assessment of the Geothermal Potential Within the BPA Marketing Area.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lund, John W.; Allen, Eliot D.

    1980-07-01

    The potential of geothermal energy is estimated that can be used for direct heat applications and electrical power generation within the Bonneville Power Administration (BPA) marketing area. The BPA marketing area includes three principal states of Oregon, Washington, and Idaho and portions of California, Montana, Wyoming, Nevada, and Utah bordering on these three states. This area covers approximately 384,000 square miles and has an estimated population of 6,760,000. The total electrical geothermal potential within this marketing area is 4077 MW/sub e/ from hydrothermal resources and 16,000 MW/sub e/ from igneous systems, whereas the total thermal (wellhead) potential is 16.15 xmore » 10/sup 15/ Btu/y. Approximately 200 geothermal resource sites were initially identified within the BPA marketing area. This number was then reduced to about 100 sites thought to be the most promising for development by the year 2000. These 100 sites, due to load area overlap, were grouped into 53 composite sites; 21-3/4 within BPA preference customer areas and 31-1/4 within nonpreference customer areas. The geothermal resource potential was then estimated for high-temperature (> 302/sup 0/F = 150/sup 0/C), intermediate-temperature (194 to 302/sup 0/F = 90 to 150/sup 0/C), and low-temperature (< 194/sup 0/F = 90/sup 0/C) resources.« less

  9. Geophysics of Geothermal Areas: State of the Art and Future Development

    NASA Astrophysics Data System (ADS)

    Mabey, Don R.

    In May 1980 a workshop organized by the Advanced School of Geophysics of the Ettore Majorana Center for Scientific Culture was held in Erice, Italy. The purpose was to present the state of the art and future development of geophysics as related to exploration for geothermal resources and the environmental impact of the development of geothermal systems. The workshop was addressed to “younger researchers working in scientific institutions and in public or private agencies and who are particularly interested in these aspects of the energy problem.” Fourteen formal lectures were presented to the workshop. This volume contains papers based on 10 of these lectures with a preface, forward, and introduction by the editors. The ten papers are “Heat Transfer in Geothermal Areas,” “Interpretation of Conductive Heat Flow Anomalies,” “Deep Electromagnetic Soundings in Geothermal Exploration,” “A Computation Method for dc Geoelectric Fields,” “Measurement of Ground Deformation in Geothermal Areas,” “Active Seismic Methods in Geothermal Exploration,” “The Role of Geophysical Investigations in the Discovery of the Latera Geothermal Field,” “Geothermal Resources Exploration in the European Community: The Geophysical Case,” “Activity Performed by AGIP (ENI Group) in the Field of Geothermal Energy,” and “Geothermal Exploration in the Western United States.” Six of the authors are from Italy, and one each is from Iceland, the Netherlands, West Germany, and the United States. All of the papers are in English.

  10. Investigations into early rift development and geothermal resources in the Pyramid Lake fault zone, Western Nevada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eisses, A.; Kell, A.; Kent, G.

    A. K. Eisses, A. M. Kell, G. Kent, N. W. Driscoll, R. E. Karlin, R. L. Baskin, J. N. Louie, S. Pullammanappallil, 2010, Investigations into early rift development and geothermal resources in the Pyramid Lake fault zone, Western Nevada: Abstract T33C-2278 presented at 2010 Fall Meeting, AGU, San Francisco, Calif., 13-17 Dec.

  11. Geothermal energy: opportunities for California commerce. Phase I report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1982-01-01

    California's geographic and end-use markets which could directly use low and moderate temperature geothermal resources are ranked and described, as well as those which have the highest potential for near-term commercial development of these resources. Building on previous market surveys, the assessment determined that out of 38 geothermal resource areas with characteristics for direct use development, five areas have no perceived impediments to near-term development: Susanville, Litchfield, Ontario Hot Springs, Lake Elsinore, and the Salton Sea Geothermal Field. Twenty-nine applications were compared with previously selected criteria to determine their near-term potential for direct use of geothermal fluids. Seven categories weremore » found to have the least impediments to development; agriculture and district heating applications are considered the highest. Ten-year projections were conducted for fossil fuel displacement from the higher rated applications. It is concluded that greenhouses have the greatest displacement of 18 x 10/sup 6/ therms per year.« less

  12. Fort Bliss Geothermal Area Data: Temperature profile, logs, schematic model and cross section

    DOE Data Explorer

    Adam Brandt

    2015-11-15

    This dataset contains a variety of data about the Fort Bliss geothermal area, part of the southern portion of the Tularosa Basin, New Mexico. The dataset contains schematic models for the McGregor Geothermal System, a shallow temperature survey of the Fort Bliss geothermal area. The dataset also contains Century OH logs, a full temperature profile, and complete logs from well RMI 56-5, including resistivity and porosity data, drill logs with drill rate, depth, lithology, mineralogy, fractures, temperature, pit total, gases, and descriptions among other measurements as well as CDL, CNL, DIL, GR Caliper and Temperature files. A shallow (2 meter depth) temperature survey of the Fort Bliss geothermal area with 63 data points is also included. Two cross sections through the Fort Bliss area, also included, show well position and depth. The surface map included shows faults and well spatial distribution. Inferred and observed fault distributions from gravity surveys around the Fort Bliss geothermal area.

  13. SESPE-FRAZIER, DIABLO, MATILIJA, DRY LAKES, SAWMILL-BADLANDS, CUYAMA, ANTIMONY, AND QUATAL ROADLESS AREAS, CALIFORNIA.

    USGS Publications Warehouse

    Frizzell, Virgil A.; Hale, William N.

    1984-01-01

    The study area, consisting of the Sespe-Frazier, Diablo, Matilija, Dry Lakes, Sawmill-Badlands, Cuyama, Antimony, and Quatal Roadless Areas, occupies about 872 sq mi in the Los Padres National Forest, California. Studies indicate that the Sespe-Frazier Roadless Area contains demonstrated resources of gold, gypsum, phosphate and bentonite; deposits in the Cuyama Roadless Area have demonstrated resources of gypsum; mines in the Antimony Roadless Area have demonstrated resources of antimony, gold, silver, and marble; and the Quatal Roadless Area has demonstrated resources of bentonite. The Sespe-Frazier Roadless Area has substantiated potential for geothermal resources suitable for direct-heat purposes, probable and substantiated potential for oil and gas resources, and probable potential for gold resources. Small areas of probable resource potential for antimony and gold were identified in Antimony Roadless Area.

  14. Cooperative geochemical investigation of geothermal resources in the Imperial Valley and Yuma areas. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Coplen, T.B.

    1973-10-01

    Preliminary studies indicate that the Imperial Valley has a large geothermal potential. In order to delineate additional geothermal systems a chemical and isotopic investigation of samples from water wells, springs, and geothermal wells in the Imperial Valley and Yuma areas was conducted. Na, K, and Ca concentrations of nearly 200 well water, spring water, hot spring, and geothermal fluid samples from the Imperial Valley area were measured by atomic absorption spectrophotometry. Fournier and Truesdell's function was determined for each water sample. Suspected geothermal areas are identified. Hydrogen and oxygen isotope abundances were determined in order to determine and to identifymore » the source of the water in the Mesa geothermal system. (JGB)« less

  15. Castle Creek known geothermal resource area: an environmental analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Spencer, S.G.; Russell, B.F.

    1979-09-01

    The Castle Creek known geothermal resource area (KGRA) is part of the large Bruneau-Grand View thermal anomaly in southwestern Idaho. The KGRA is located in the driest area of Idaho and annual precipitation averages 230 mm. The potential of subsidence and slope failure is high in sediments of the Glenns Ferry Formation and Idaho Group found in the KGRA. A major concern is the potential impact of geothermal development on the Snake River Birds of Prey Natural Area which overlaps the KGRA. Any significant economic growth in Owyhee County may strain the ability of the limited health facilities in themore » county. The Idaho Archaeological survey has located 46 archaeological sites within the KGRA.« less

  16. Geophysical investigations of the geologic and hydrothermal framework of the Pilgrim Springs Geothermal Area, Alaska

    USGS Publications Warehouse

    Glen, Jonathan; McPhee, Darcy K.; Bedrosian, Paul A.

    2014-01-01

    Pilgrim Hot Springs, located on the Seward Peninsula in west-central Alaska, is characterized by hot springs, surrounding thawed regions, and elevated lake temperatures. The area is of interest because of its potential for providing renewable energy for Nome and nearby rural communities. We performed ground and airborne geophysical investigations of the Pilgrim Springs geothermal area to identify areas indicative of high heat flow and saline geothermal fluids, and to map key structures controlling hydrothermal fluid flow. Studies included ground gravity and magnetic measurements, as well as an airborne magnetic and frequency-domain electromagnetic (EM) survey. The structural and conceptual framework developed from this study provides critical information for future development of this resource and is relevant more generally to our understanding of geothermal systems in active extensional basins. Potential field data reveal the Pilgrim area displays a complex geophysical fabric reflecting a network of intersecting fault and fracture sets ranging from inherited basement structures to Tertiary faults. Resistivity models derived from the airborne EM data reveal resistivity anomalies in the upper 100 m of the subsurface that suggest elevated temperatures and the presence of saline fluids. A northwest trending fabric across the northeastern portion of the survey area parallels structures to the east that may be related to accommodation between the two major mountain ranges south (Kigluaik) and east (Bendeleben) of Pilgrim Springs. The area from the springs southward to the range front, however, is characterized by east-west trending, range-front-parallel anomalies likely caused by late Cenozoic structures associated with north-south extension that formed the basin. The area around the springs (~10 km2 ) is coincident with a circular magnetic high punctuated by several east-west trending magnetic lows, the most prominent occurring directly over the springs. These features

  17. Soil mercury levels in the area surrounding the Cerro Prieto geothermal complex, MEXICO.

    PubMed

    Pastrana-Corral, M A; Wakida, F T; García-Flores, E; Rodriguez-Mendivil, D D; Quiñonez-Plaza, A; Piñon-Colin, T D J

    2016-08-01

    Even though geothermal energy is a renewable energy source that is seen as cost-effective and environmentally friendly, emissions from geothermal plants can impact air, soil, and water in the vicinity of geothermal power plants. The Cerro Prieto geothermal complex is located 30 km southeast of the city of Mexicali in the Mexican state of Baja California. Its installed electricity generation capacity is 720 MW, being the largest geothermal complex in Mexico. The objective of this study was to evaluate whether the emissions generated by the geothermal complex have increased the soil mercury concentration in the surrounding areas. Fifty-four surface soil samples were collected from the perimeter up to an approximate distance of 7660 m from the complex. Additionally, four soil depth profiles were performed in the vicinity of the complex. Mercury concentration in 69 % of the samples was higher than the mercury concentration found at the baseline sites. The mercury concentration ranged from 0.01 to 0.26 mg/kg. Our results show that the activities of the geothermal complex have led to an accumulation of mercury in the soil of the surrounding area. More studies are needed to determine the risk to human health and the ecosystems in the study area.

  18. A brief description of geological and geophysical exploration of the Marysville geothermal area

    NASA Technical Reports Server (NTRS)

    Blackwell, D. D.; Brott, C. A.; Goforth, T. T.; Holdaway, M. J.; Morgan, P.; Petefish, D.; Rape, T.; Steele, J. L.; Spafford, R. E.; Waibel, A. F.

    1974-01-01

    Extensive geological and geophysical surveys were carried out at the Marysville geothermal area during 1973 and 1974. The area has high heat flow (up to microcalories per square centimeter-second, a negative gravity anomaly, high electrical resistivity, low seismic ground noise, and nearby microseismic activity. Significant magnetic and infrared anomalies are not associated with the geothermal area. The geothermal anomaly occupies the axial portion of a dome in Precambrian sedimentary rocks intruded by Cretaceous and Cenozoic granitic rocks. The results from a 2.4-km-deep test well indicate that the cause of the geothermal anomaly is hydrothermal convection in a Cenozoic intrusive. A maximum temperature of 95 C was measured at a depth of 500 m in the test well.

  19. Pyramid Lake Renewable Energy Project

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    John Jackson

    2008-03-14

    The Pyramid Lake Paiute Tribe is a federally recognized Tribe residing on the Pyramid Lake Reservation in western Nevada. The funding for this project was used to identify blind geothermal systems disconnected from geothermal sacred sites and develop a Tribal energy corporation for evaluating potential economic development for profit.

  20. RAINBOW LAKE WILDERNESS AND FLYNN LAKE WILDERNESS STUDY AREA, WISCONSIN.

    USGS Publications Warehouse

    Cannon, W.F.; Dunn, Maynard L.

    1984-01-01

    The Rainbow Lake Wilderness and Flynn Lake Wilderness study area in Wisconsin are contiguous and were studied as a unit. The rainbow Lake Wilderness contains a demonstrated resource of about 210,000 tons of commercial-quality peat in an area of substantiated peat resource potential. The Flynn Lake Wilderness study area contains a demonstrated resource of about 300,000 tons of commercial-quality peat in an area of substantiated peat resource potential. These deposits, however, are of limited importance because larger deposits of similar material are abundant outside the areas, closer to present markets. Rocks in the subsurface contain a low-grade copper resource identified by mining company exploration drilling. Although this is an area of substantiated copper resource potential, it is a low-grade resource, thin and generally at great depth.

  1. Regional and local networks of horizontal control, Cerro Prieto geothermal area

    USGS Publications Warehouse

    Massey, B.L.

    1979-01-01

    The Cerro Prieto geothermal area in the Mexicali Valley 30 km southeast of Mexicali, Baja California, is probably deforming due to (1) the extraction of large volumes of steam and hot water, and (2) active tectonism. Two networks of precise horizontal control were established in Mexicali Valley by the U.S. Geological Survey in 1977 - 1978 to measure both types of movement as they occur. These networks consisted of (1) a regional trilateration net brought into the mountain ranges west of the geothermal area from survey stations on an existing U.S. Geological Survey crustal-strain network north of the international border, and (2) a local net tied to stations in the regional net and encompassing the area of present and planned geothermal production. Survey lines in this net were selected to span areas of probable ground-surface movements in and around the geothermal area. Electronic distance measuring (EDM) instruments, operating with a modulated laser beam, were used to measure the distances between stations in both networks. The regional net was run using a highly precise long-range EDM instrument, helicopters for transportation of men and equipment to inaccessible stations on mountain peaks, and a fixed wing airplane flying along the line of sight. Precision of measurements with this complex long-range system approached 0-2 ppm of line length. The local net was measured with a medium-range EDM instrument requiring minimal ancillary equipment. Precision of measurements with this less complex system approached 3 ppm for the shorter line lengths. The detection and analysis of ground-surface movements resulting from tectonic strains or induced by geothermal fluid withdrawal is dependent on subsequent resurveys of these networks. ?? 1979.

  2. Microbial community dynamics in Inferno Crater Lake, a thermally fluctuating geothermal spring

    PubMed Central

    Ward, Laura; Taylor, Michael W; Power, Jean F; Scott, Bradley J; McDonald, Ian R; Stott, Matthew B

    2017-01-01

    Understanding how microbial communities respond and adjust to ecosystem perturbation is often difficult to interpret due to multiple and often simultaneous variations in observed conditions. In this research, we investigated the microbial community dynamics of Inferno Crater Lake, an acidic geothermal spring in New Zealand with a unique thermal cycle that varies between 30 and 80 °C over a period of 40–60 days. Using a combination of next-generation sequencing, geochemical analysis and quantitative PCR we found that the microbial community composition was predominantly chemolithotrophic and strongly associated with the thermal cycle. At temperatures >65 °C, the microbial community was dominated almost exclusively by sulphur-oxidising archaea (Sulfolobus-like spp.). By contrast, at mesophilic temperatures the community structure was more mixed, comprising both archaea and bacteria but dominated primarily by chemolithotrophic sulphur and hydrogen oxidisers. Multivariate analysis of physicochemical data confirmed that temperature was the only significant variable associated with community turnover. This research contributes to our understanding of microbial community dynamics in variable environments, using a naturally alternating system as a model and extends our limited knowledge of acidophile ecology in geothermal habitats. PMID:28072418

  3. Microbial community dynamics in Inferno Crater Lake, a thermally fluctuating geothermal spring.

    PubMed

    Ward, Laura; Taylor, Michael W; Power, Jean F; Scott, Bradley J; McDonald, Ian R; Stott, Matthew B

    2017-05-01

    Understanding how microbial communities respond and adjust to ecosystem perturbation is often difficult to interpret due to multiple and often simultaneous variations in observed conditions. In this research, we investigated the microbial community dynamics of Inferno Crater Lake, an acidic geothermal spring in New Zealand with a unique thermal cycle that varies between 30 and 80 °C over a period of 40-60 days. Using a combination of next-generation sequencing, geochemical analysis and quantitative PCR we found that the microbial community composition was predominantly chemolithotrophic and strongly associated with the thermal cycle. At temperatures >65 °C, the microbial community was dominated almost exclusively by sulphur-oxidising archaea (Sulfolobus-like spp.). By contrast, at mesophilic temperatures the community structure was more mixed, comprising both archaea and bacteria but dominated primarily by chemolithotrophic sulphur and hydrogen oxidisers. Multivariate analysis of physicochemical data confirmed that temperature was the only significant variable associated with community turnover. This research contributes to our understanding of microbial community dynamics in variable environments, using a naturally alternating system as a model and extends our limited knowledge of acidophile ecology in geothermal habitats.

  4. The Preston Geothermal Resources; Renewed Interest in a Known Geothermal Resource Area

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wood, Thomas R.; Worthing, Wade; Cannon, Cody

    2015-01-01

    The Preston Geothermal prospect is located in northern Cache Valley approximately 8 kilometers north of the city of Preston, in southeast Idaho. The Cache Valley is a structural graben of the northern portion of the Basin and Range Province, just south of the border with the Eastern Snake River Plain (ESRP). This is a known geothermal resource area (KGRA) that was evaluated in the 1970's by the State of Idaho Department of Water Resources (IDWR) and by exploratory wells drilled by Sunedco Energy Development. The resource is poorly defined but current interpretations suggest that it is associated with the Cachemore » Valley structural graben. Thermal waters moving upward along steeply dipping northwest trending basin and range faults emanate in numerous hot springs in the area. Springs reach temperatures as hot as 84° C. Traditional geothermometry models estimated reservoir temperatures of approximately 125° C in the 1970’s study. In January of 2014, interest was renewed in the areas when a water well drilled to 79 m (260 ft) yielded a bottom hole temperature of 104° C (217° F). The well was sampled in June of 2014 to investigate the chemical composition of the water for modeling geothermometry reservoir temperature. Traditional magnesium corrected Na-K-Ca geothermometry estimates this new well to be tapping water from a thermal reservoir of 227° C (440° F). Even without the application of improved predictive methods, the results indicate much higher temperatures present at much shallower depths than previously thought. This new data provides strong support for further investigation and sampling of wells and springs in the Northern Cache Valley, proposed for the summer of 2015. The results of the water will be analyzed utilizing a new multicomponent equilibrium geothermometry (MEG) tool called Reservoir Temperature Estimate (RTEst) to obtain an improved estimate of the reservoir temperature. The new data suggest that other KGRAs and overlooked areas may

  5. Some New Constraints On The Stratigraphic And Structural Setting Of The Soda Lake Geothermal Field, Churchill County, Nevada - McLACHLAN, Holly S. and FAULDS, James E., Nevada Bureau of Mines and Geology, University of Nevada, Reno, NV 89557

    NASA Astrophysics Data System (ADS)

    McLachlan, H. S.

    2012-12-01

    Our research group is currently conducting a regional survey to identify favorable structural settings of producing and prospective geothermal fields in the Great Basin. The Soda Lake geothermal field - one of the oldest consistently producing fields in this study region - is located in west-central Nevada near the heart of the Carson Sink. Producing and prospective geothermal fields in the surrounding highlands are hosted in 1) fault termination zones (Desert Queen), 2) accommodation zones (Brady's Hot Springs) and 3) fault step-overs (Desert Peak). However, the structural setting is challenging to identify at the Soda Lake field, because it lies in the central part of a large basin with no nearby bedrock exposures. The well field at Soda Lake is centered ~3.5 km NNE of the Holocene Soda Lake maar, from which it takes its name. The geothermal field was identified serendipitously during the drilling of an irrigation survey well in the early 20th century. Modern exploratory drilling at the field began in the mid-1970s and has continued sporadically to the present. There are currently more than 28 500+ m wells at and near the production site. The exceptional drilling density at Soda Lake allows for comparatively reliable correlation of stratigraphy in the subsurface below the feature-poor Carson Sink. Stratigraphy in the Soda Lake geothermal area is relatively "layer cake" at the scale of the well field. Unconsolidated sediments extend more than 1000 m below surface. The upper few hundred meters are composed of fluvial and lacustrine sediments derived from Sierran batholith source rocks. The deeper basin fill derives from more proximal mafic to felsic Miocene volcanic rocks along the basin margins. At ~450-650 m depth, basin sediments are interrupted by a 5.11 Ma trachytic basalt of restricted lateral extent and variable thickness. Most wells intercept ~50-250 m of fine lacustrine sediments below this basalt body before intercepting the basin floor. Basin floor rocks

  6. Photogeologic and thermal infrared reconnaissance surveys of the Los Negritos-Ixtlan de los Hervores geothermal area, Michoacan, Mexico

    USGS Publications Warehouse

    Gomez, Valle R.; Friedman, J.D.; Gawarecki, S.J.; Banwell, C.J.

    1970-01-01

    New techniques, involving interpretation of panchromatic, ektachrome and ektachrome infrared aerographic photogaphs and thermographic infrared imagery recording emission from the earth's surface in middle and far infrared wavelengths (3-5??m and 8-14??m), are being introduced in geothermal investigations in Mexico to identify outstanding structural and geologic features in a rapid and economical manner. The object of this work is to evaluate the new airborne infrared techniques and equipment as a complement to the data obtained from panchromatic aerial photography. This project is part of the Mexican remote sensing program of natural resources carried out under the auspices of the Comision Nacional del Espacio Exterior and in which the Research Institute (Instituto de Investigaciones de la Industria Electrica) is actively participating. The present study was made cooperatively with the U.S. National Aeronautics and Space Administration and the U.S. Geological Survey. The Los Negritos-Ixtlan de los Hervores geothermal fields are located east of Lake Chapala at the intersection of the Sierra Madre occidental and the west-central segment of the neovolcanic axis of Mexico. The two principal zones of hydrothermal activity occur in a tectonic trench filled with lake sediments of the Quaternary intercalated with Quaternary and Holocene volcanic rocks and characterized by an intricate system of block-fault tectonics, part of the Chapala-Acambay tectonic system, along which there has been volcanic activity in modern time. Surface manifestations of geothermal activity consist of relatively high heat flow and hot springs, small geysers and small steam vents aligned along an E-W axis at Ixtlan, possibly at the intersection of major fault trends and mud volcanoes and hot pools aligned NE-SW at Los Negritos. More than 20 exit points of thermal waters are shown on infrared imagery to be aligned along an extension of the Ixtlan fault between Ixtlan and El Salitre. A narrow zone of

  7. Applicability of `GREATEM' system in mapping geothermal regions in volcanic areas

    NASA Astrophysics Data System (ADS)

    Verma, S. K.; Mogi, T.; Abd Allah, S.

    2010-12-01

    The ‘GREATEM’ helicopter borne TEM system employs a long grounded cable as transmitter while a light weight receiver coil is flown below a helicopter. This arrangement greatly simplifies the flying logistics and speed of the survey. Also there is very little reduction in the anomaly amplitude when the survey altitude is increased. This is a great advantage particularly in volcanic regions usually having rough topography, as the ‘GREATEM’ survey can be done with helicopter flying at a safe height. Many volcanic areas have anomalous geothermal regions containing hydrothermal fluids. Eruption of volcanoes may cause changes in the thermal character and spatial distribution of these regions. Mapping of these regions is important as they may be associated with hazards. Sometimes, if the temperature is high and volume of the geothermal region is large, they can provide a good source of geothermal energy. Applicability of ‘GREATEM’ system in mapping geothermal regions in volcanic areas is studied by numerical modeling. We have considered a 3D conductor at a shallow depth (50 t0 100m), representing the anomalous geothermal region with dimensions of 500m X 500m X 500m. Different types of geological host environment are considered by varying their resistivities from 10 Ohm.m to 2000 Ohm.m. The ‘GREATEM’ response is analyzed as ‘Percentage Difference (PD)’ over the response produced by the host environment. It is found that the “GREATEM’ system can delineate the geothermal region well. Many geothermal regions are associated with a deeper (> 1 km) reservoir of much larger dimensions. In this situation also it is found that the ‘GREATEM’ system can pick up the response of the shallower geothermal region against the background response of different types of geological host environment containing the deeper reservoir (Figure 1).

  8. Identification of geothermal system using 2D audio magnetotelluric method in Telomoyo volcanic area

    NASA Astrophysics Data System (ADS)

    Romadlon, Arriqo'Fauqi; Niasari, Sintia Windhi

    2017-07-01

    Geothermal area of Candi Umbul Telomoyo is one of geothermal fields in Indonesia. This geothermal field is located in the Grabag district, Magelang, Central Java. This geothermal field was formed in a volcanic quarter. The main aim in this study is to identify geothermal system at Telomoyo volcanic area through synthetic model analysis. There are surface manifestations such as warm springs and altered rocks. Results of geochemistry study showed reservoir's temperature was 230°C. The Warm spring in Candi Umbul was the outflow zone of the Telomoyo geothermal system. The Telomoyo geothermal system was indicated chloride-bicarbonate type of warm spring. In addition, the results of geological mapping indicate that the dominant fault structure has southwest-northeast orientation. The fault was caused by the volcanic activity of mount Telomoyo. In this research conducted data analysis from synthetics model. It aims to estimate the response of magnetotelluric methods in various models of geothermal systems. In this study, we assumed three models of geothermal system in Candi Umbul-Telomoyo area. From the data analysis it was known that the model 1 and model 2 can be distinguished if the measurements were conducted in a frequency range of 0.01 Hz to 1000 Hz. In response of tipper (Hz) had a small value on all models at all measurement points, so the tipper cannot distinguish between model 1, model 2 and model 3. From this analysis was known that TM mode is more sensitive than TE mode at the resistivity and phase responses.

  9. DARPA Workshop on Geothermal Energy for Military Operations

    DTIC Science & Technology

    2010-05-01

    is administered by its Geothermal Program Office (GPO) at the Navy Air Weapons Station, China Lake, CA. GPO manages the Coso Geo- thermal Field at...advanced geothermal technologies might reduce the risk and cost to the point where the U.S. military would be able to take advantage. Supplying geothermal...was con- vened to explore whether investment in advanced geothermal technologies might reduce the risk and cost to the point where the U.S. military

  10. Deformation at Krafla and Bjarnarflag geothermal areas, Northern Volcanic Zone of Iceland, 1993-2015

    NASA Astrophysics Data System (ADS)

    Drouin, Vincent; Sigmundsson, Freysteinn; Verhagen, Sandra; Ófeigsson, Benedikt G.; Spaans, Karsten; Hreinsdóttir, Sigrún

    2017-09-01

    The Krafla volcanic system has geothermal areas within the Krafla caldera and at Bjarnarflag in the Krafla fissure swarm, 9-km south of the Krafla caldera. Arrays of boreholes extract geothermal fluids for power plants in both areas. We collected and analyzed InSAR, GPS, and leveling data spanning 1993-2015 in order to investigate crustal deformation in these areas. The volcanic zone hosting the geothermal areas is also subject to large scale regional deformation processes, including plate spreading and deflation of the Krafla volcanic system. These deformation processes have to be taken into account in order to isolate the geothermal deformation signal. Plate spreading produces the largest horizontal displacements, but the regional deformation pattern also suggests readjustment of the Krafla system at depth after the 1975-1984 Krafla rifting episode. Observed deformation can be fit by an inflation source at about 20 km depth north of Krafla and a deflation source at similar depth directly below the Krafla caldera. Deflation signal along the fissure swarm can be reproduced by a 1-km wide sill at 4 km depth closing by 2-4 cm per year. These sources are considered to approximate the combined effects of vertical deformation associated with plate spreading and post-rifting response. Local deformation at the geothermal areas is well resolved in addition to these signals. InSAR shows that deformation at Bjarnarflag is elongated along the direction of the Krafla fissure swarm (∼ 4 km by ∼ 2 km) while it is circular at Krafla (∼ 5 km diameter). Rates of deflation at Krafla and Bjarnarflag geothermal areas have been relatively steady. Average volume decrease of about 6.6 × 105 m3/yr for Krafla and 3.9 × 105 m3/yr for Bjanarflag are found at sources located at ∼ 1.5 km depth, when interpreted by a spherical point source of pressure. This volume change represents about 8 × 10-3 m3/ton of the mass of geothermal fluid extracted per year, indicating important renewal

  11. Analysis of Geothermal Pathway in the Metamorphic Area, Northeastern Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, C.; Wu, M. Y.; Song, S. R.; Lo, W.

    2016-12-01

    A quantitative measure by play fairway analysis in geothermal energy development is an important tool that can present the probability map of potential resources through the uncertainty studies in geology for early phase decision making purpose in the related industries. While source, pathway, and fluid are the three main geologic factors in traditional geothermal systems, identifying the heat paths is critical to reduce drilling cost. Taiwan is in East Asia and the western edge of Pacific Ocean, locating on the convergent boundary of Eurasian Plate and Philippine Sea Plate with many earthquake activities. This study chooses a metamorphic area in the western corner of Yi-Lan plain in northeastern Taiwan with high geothermal potential and several existing exploration sites. Having high subsurface temperature gradient from the mountain belts, and plenty hydrologic systems through thousands of millimeters annual precipitation that would bring up heats closer to the surface, current geothermal conceptual model indicates the importance of pathway distribution which affects the possible concentration of extractable heat location. The study conducts surface lineation analysis using analytic hierarchy process to determine weights among various fracture types for their roles in geothermal pathways, based on the information of remote sensing data, published geologic maps and field work measurements, to produce regional fracture distribution probability map. The results display how the spatial distribution of pathways through various fractures could affect geothermal systems, identify the geothermal plays using statistical data analysis, and compare against the existing drilling data.

  12. Honey Lake Project

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Boren, K.L.; Johnson, K.R.

    1978-11-01

    Thirty units of a planned 205 geothermally heated hydroponic greenhouses are producing European cucumbers and tropic tomatoes near Wendel, California. The planned utilization of the geothermal resource in this project, hydroponics, in general, and the Honey Lake system is described. (MHR)

  13. High-potential geothermal energy resource areas of Nigeria and their geologic and geophysical assessment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Babalola, O.O.

    1984-04-01

    The widespread occurrence of geothermal manifestations in Nigeria is significant because the wide applicability and relative ease of exploitation of geothermal energy is of vital importance to an industrializing nation like Nigeria. There are two known geothermal resource areas (KGRAs) in Nigeria: the Ikogosi Warm Springs of Ondo State and the Wikki Warm Springs of Bauchi State. These surficial effusions result from the circulation of water to great depths through faults in the basement complex rocks of the area. Within sedimentary areas, high geothermal gradient trends are identified in the Lagos subbasin, the Okitipupa ridge, the Auchi-Agbede are of themore » Benin flank/hinge line, and the Abakaliki anticlinorium. The deeper Cretaceous and Tertiary sequences of the Niger delta are geopressured geothermal horizons. In the Benue foldbelt, extending from the Abalaliki anticlinorium to the Keana anticline and the Zambuk ridge, several magmatic intrusions emplaced during the Late Cretaceous line the axis of the Benue trough. Positive Bouguer gravity anomalies also parallel this trough and are interpreted to indicate shallow mantle. Parts of this belt and the Ikom, the Jos plateau, Bauchi plateau, and the Adamawa areas, experienced Cenozoic volcanism and magmatism.« less

  14. Geothermal area detection using Landsat ETM+ thermal infrared data and its mechanistic analysis—A case study in Tengchong, China

    NASA Astrophysics Data System (ADS)

    Qin, Qiming; Zhang, Ning; Nan, Peng; Chai, Leilei

    2011-08-01

    Thermal infrared (TIR) remote sensing is an important technique in the exploration of geothermal resources. In this study, a geothermal survey is conducted in Tengchong area of Yunnan province in China using TIR data from Landsat-7 Enhanced Thematic Mapper Plus (ETM+) sensor. Based on radiometric calibration, atmospheric correction and emissivity calculation, a simple but efficient single channel algorithm with acceptable precision is applied to retrieve the land surface temperature (LST) of study area. The LST anomalous areas with temperature about 4-10 K higher than background area are discovered. Four geothermal areas are identified with the discussion of geothermal mechanism and the further analysis of regional geologic structure. The research reveals that the distribution of geothermal areas is consistent with the fault development in study area. Magmatism contributes abundant thermal source to study area and the faults provide thermal channels for heat transfer from interior earth to land surface and facilitate the present of geothermal anomalies. Finally, we conclude that TIR remote sensing is a cost-effective technique to detect LST anomalies. Combining TIR remote sensing with geological analysis and the understanding of geothermal mechanism is an accurate and efficient approach to geothermal area detection.

  15. Three-Component Long Offset Surface Seismic Survey Data Used to Find Large Aperture Fractures in Geothermal Resources - San Emidio Geothermal Resource Area

    DOE Data Explorer

    Ian Warren

    2010-09-15

    P and S-wave datasets and associated report studying the ability to use three-component long offset surface seismic surveys to find large aperture fractures in geothermal resources at the San Emidio geothermal resource area in Washoe County, Nevada.

  16. Modeling of subsurface structures in Telomoyo Volcano geothermal area, Magelang using 1-D magnetotelluric method

    NASA Astrophysics Data System (ADS)

    Sarjan, Achmad Fajar Narotama; Niasari, Sintia Windhi

    2017-07-01

    There are some of geothermal prospects around Java Island. One of them are located in Telomoyo Volcano area, Magelang, Central Java. The existence of hot spring manifestations in Telomoyo Volcano area shows the presence of geothermal system. The upflow zone of this geothermal system was formed in the caldera of Telomoyo Volcano area, while the outflow zone was formed around Candi Umbul. In addition, from the geological map shows a geological structure assumed as a normal fault with southwest-northeast orientation that was caused by the volcanic activity. The aim of this research is to give a brief introduction about subsurface resistivity beneath Telomoyo Volcano area using 1-D magnetotelluric forward model. Thus, we can determine the possibility of data that will obtained during the acquisition process based on the geological model that was made. The apparent resistivity, phase, and period values were obtained from the forward modeling process. The result from this study is a 1-D resistivity section with synthetics curves of each geothermal model. In each model the presence of clay cap characterized by a low resistivity layer. A layer below the clay cap with a medium resistivity value interpreted as the reservoir of this geothermal system. The heat source of this geothermal area is characterized by a low resistivity that is located at depth 4000-5500m. This study is still in progress to acquire the exact values of resistivity from each layer from the field data acquisition in Telomoyo Volcano area, Magelang.

  17. Marine and land active-source seismic investigation of geothermal potential, tectonic structure, and earthquake hazards in Pyramid Lake, Nevada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eisses, A.; Kell, A.; Kent, G.

    Amy Eisses, Annie M. Kell, Graham Kent, Neal W. Driscoll, Robert E. Karlin, Robert L. Baskin, John N. Louie, Kenneth D. Smith, Sathish Pullammanappallil, 2011, Marine and land active-source seismic investigation of geothermal potential, tectonic structure, and earthquake hazards in Pyramid Lake, Nevada: presented at American Geophysical Union Fall Meeting, San Francisco, Dec. 5-9, abstract NS14A-08.

  18. Geochemical Study of Ampallas Geothermal Area, Mamuju District, West Sulawesi Province

    NASA Astrophysics Data System (ADS)

    Fauziyyah, F.; Prabowo, T. R.; Shalihin, M. G. J.; Setiawan, D. I.; Yushantarti, A.

    2016-09-01

    Ampallas is one of the areas with geothermal potential which located in Mamuju district, near from the capital city of West Sulawesi. This research was carried out to understand the characteristic of this geothermal field based on chemistry of the surface manifestation, including fluid characteristic and soil anomaly. Geothermal research in Ampallas area focused on 4 hot springs; Ampallas, Batupane, Karema, and Gantungan. With average temperature around 34 - 67°C. Ampallas 1,2,3,4,7,8 hot springs water type is chloride - bicarbonate, which means it came from the reservoir while Batupane, Gantungan, Karema and Ampallas 5 are all bicarbonate type. Ampallas 1,2,3,4,7,8, Karema and Gantungan hot springs fluid plotted in partial equilibrium zone while Batupane and Ampallas 5 plotted in immature water zone. It means the Ampallas hot springs (except Ampallas-5) mixed with meteoric water right after reached the equilibrium state. It is also concluded that Ampallas 5 hot springs came from the same reservoir with Batupane, but not Gantungan and Karema hot springs. The speculative resource potential of Ampallas geothermal system is estimated around 30 MWe. But if detailed geophysical method was applied the result could be more accurate.

  19. FINAL TECHNICAL REPORT, U.S. Department of Energy: Award No. DE-EE0002855 "Demonstrating the Commercial Feasibility of Geopressured-Geothermal Power Development at Sweet Lake Field - Cameron Parish, Louisiana"

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gayle, Phillip A., Jr.

    The goal of the project was to demonstrate the commercial feasibility of geopressured-geothermal power development by exploiting the extraordinarily high pressured hot brines know to exist at depth near the Sweet Lake oil and gas field in Cameron Parish, Louisiana. The existence of a geopressured-geothermal system at Sweet Lake was confirmed in the 1970's and 1980's as part of DOE's Geopressured-Geothermal Program. That program showed that the energy prices at the time could not support commercial production of the resource. Increased electricity prices and technological advancements over the last two decades, combined with the current national support for developing clean,more » renewable energy and the job creation it would entail, provided the justification necessary to reevaluate the commercial feasibility of power generation from this vast resource.« less

  20. Geohydrology of the lowland lakes area, Anchorage, Alaska

    USGS Publications Warehouse

    Zenone, Chester

    1976-01-01

    Unconsolidated deposits, chiefly of glacial origin, make up the surficial geologic materials in the Anchorage lowland lakes area , the western part of the Anchorage glacial outwash plain. Postglacial accumulation of peat, commonly 5 to 10 feet thick, and the presence of ground water at or very near the surface combine to create the swamp-muskeg terrane of much of the area. Deeper, confined ground water is also present beneath thick silt and clay layers that underlie the surficial deposits. Domestic water supply for the lowland lakes area is provided largely by public-supply wells completed in the deep, confined aquifers. No large perennial streams traverse the area, thus streamflow is not a major parameter in the area 's natural water balance. The major uses of surface water are recreational, including fishing and boating at several of the larger lakes, and private and commercial aircraft operations at Hood-Spenard Lakes floatplane base. The hydrology and water balance of these lakes is complex. Water levels in some lakes appear to be closely related to adjacent ground-water levels. Other lakes are evidently perched above the local water table. The relation of lake level to adjacent ground-water level may vary along the shoreline of a single lake. The effect of residential development practices on lake basin water balance is not completely understood. At Sand Lake, the largest lake in this area of rapid urbanization, the water level has declined about 6 feet since the early 1960's. (Woodard-USGS)

  1. Geothermal Potential of Ascension Island, South Atlantic.

    DTIC Science & Technology

    1982-11-05

    7AD-A141 763 GEOTHERMAL POTENTIAL OF ASCENSION ISLAND SOUTH ATLANTIC 1/1. (U) UTAH UNIV RESEARCH IN T SALT LAKE CITY EARTH U LfIS SCIENCE LAB D L...STANDARDS 1%A A ~ 7- ESMC-TR-83-02 Geothermal Potential Of Ascension Island, South Atlantic Dennis L. Nielson Bruce S. Sibbett University Of Utah...Security Classification) Geothermal Potential of Ascension Island, South Atlantic 12 PERSONAL AUTHOR(S) Dennis L. Neilson and Bruce S. Sibbett IIa TYPE

  2. Reconnaissance data on lakes in the Alpine Lakes Wilderness Area, Washington

    USGS Publications Warehouse

    Dethier, David P.; Heller, Paul L.; Safioles, Sally A.

    1979-01-01

    Sixty lakes in the Alpine Lakes Wilderness Area have been sampled from rubber rafts or helicopter to obtain information on their physical setting and on present water-quality conditions. The lakes are located near the crest of the Cascade Range in Chelan and King Counties, Washington. Basic data from these lakes will be useful for planners concerned with lake and wilderness management, and of interest to hikers and other recreationists who use the lakes.

  3. Fusion of Terra-MODIS and Landsat TM data for geothermal sites investigation in Jiangsu Province, China

    NASA Astrophysics Data System (ADS)

    Chen, Shengbo

    2006-01-01

    Geothermal resources are generally confined to areas of the Earth's crust where heat flow higher than in surrounding areas heats the water contained in permeable rocks (reservoirs) at depth. It is becoming one of attractive solutions for clean and sustainable energy future for the world. The geothermal fields commonly occurs at the boundaries of plates, and only occasionally in the middle of a plate. The study area, Jiangsu Province, as an example, located in the east of China, is a potential area of geothermal energy. In this study, Landsat thematic Mapper (TM) data were georeferenced to position spatially the geothermal energy in the study area. Multi-spectral infrared data of Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra platform were georeferenced to Landsat TM images. Based on the Wien Displacement Law, these infrared data indicate the surface emitted radiance under the same atmospheric condition, and stand for surface bright temperature respectively. Thus, different surface bright temperature data from Terra-MODIS band 20 or band 31 (R), together with Landsat TM band 4 (G) and band 3 (B) separately, were made up false color composite images (RGB) to generate the distribution maps of surface bright temperatures. Combing with geologic environment and geophysical anomalies, the potential area of geothermal energy with different geo-temperature were mapped respectively. Specially, one geothermal spot in Qinhu Lake Scenery Area in Taizhou city was validated by drilling, and its groundwater temperature is up to some 51°.

  4. Reducing the Geothermal Exploration Risk by Carbon Dioxide Soil Flux Investigations

    NASA Astrophysics Data System (ADS)

    Carapezza, Maria Luisa; Barberi, Franco; Ranaldi, Massimo; Ricci, Tullio; Tarchini, Luca; De Simone, Gabriele; Gattuso, Alessandro; Silvestri, Mario

    2013-04-01

    In the exploration of medium to high enthalpy geothermal resources it happens rather frequently that deep wells find high temperatures but are not productive because they don't cross any permeable fractured reservoir. Because of the high cost of deep drillings, this aspect represents one of the main economic risks of geothermal exploration. A detailed survey of diffuse CO2 soil flux may allow to identify from the surface the permeable portions of a deep-seated actively degassing geothermal reservoir, drastically reducing this risk. In order to test the effectiveness of CO2 soil flux as a geothermal exploration tool we selected two volcanic areas north of Rome, Latera caldera and Marta zone near lake Bolsena, both hosting a geothermal reservoir with T>200 °C and where productive and non-productive wells had been drilled in the past. We proved that in both zones productive wells are located on high CO2 soil flux zones, whereas the not-productive wells are sited on low flux areas. In addition the surveys allowed to identify some as yet unexplored portions of the geothermal reservoirs where future wells should be conveniently located. Use of the same technique in the medium enthalpy geothermal system of Torre Alfina, Central Italy (T=140°C) showed that the presence of a thick impervious rock cover may be very effective in preventing gas leakages from the reservoir to the surface. Promising results have been obtained also by CO2 soil flux surveys in some geothermal areas of Honduras (Platanares, Azacualpa) and Costa Rica (Las Pailas). Obviously, CO2 flux cannot provide any estimate of temperature at depth, which has to be assessed with other geochemical or geophysical exploration techniques.

  5. Hydrologic reconnaissance of the geothermal area near Klamath Falls, Oregon

    USGS Publications Warehouse

    Sammel, E.A.; Peterson, D.L.

    1976-01-01

    geothermal systems probably occurs as water, in the deeper basalt rocks, penetrating downward along the extensive fracture zones that transect the area.Shallow meteoric water that is assumed to be the source of the thermal waters has low dissolved-solids concentrations generally dominated by calcium and bicarbonate. During its passage through the geothermal reservoir, the water gains dissolved solids in amounts up to about 900 milligrams per liter. Sodium and sulfate become the dominant ions. Chloride concentrations remain relatively low, and silica concentrations increase from an average of about 35 milligrams per liter to about 100 milligrams per liter.Both cation ratios and silica concentrations in the hot waters indicate that reservoir temperatures are relatively low. The estimate arrived at in this study for the minimum reservoir temperature is 130°C. Silica concentrations are probably more reliable than cation ratios for estimates of reservoir temperatures for these waters. Other chemical indicators, including oxygen and deuterium isotopes, are consistent in indicating that reservoir temperatures are probably not much greater than the minimum estimate.Temperature distributions and heat flows in the shallow rocks of the area are strongly influenced by convective flow of water. Most observed temperature gradients and estimated heat flows are believed to be unreliable as indicators of conditions in or directly above the thermal reservoir. Some evidence from temperature profiles suggests, however, that heat flow in the Lower Klamath Lake basin is about 1.4 microcalories per square centimeter per second (1.4 HFU), a value that is near the minimum expected for the Basin and Range province.The net thermal flux discharged from springs and wells in the area is estimated to be on the order of 2 x 106 calories per second. Discharge by thermal waters into the shallow ground-water system beneath land surface may be many times this amount. Reportedly, at present only about 1

  6. Fluid geochemistry of Fault zone hydrothermal system in the Yidun-Litang area, eastern Tibetan Plateau geothermal belt

    NASA Astrophysics Data System (ADS)

    Shi, Z.; Wang, G.

    2017-12-01

    Understanding the geochemical and geothermal characteristic of the hydrothermal systems provide useful information in appropriate evaluating the geothermal potential in this area. In this paper, we investigate the chemical and isotopic composition of thermal water in an underexploited geothermal belt, Yidun-Litang area, in eastern Tibetan Plateau geothermal belt. 24 hot springs from the Yidun and Litang area were collected and analyzed. The chemical facies of the hot springs are mainly Na-HCO3 type water. Water-rock interaction, cation exchange are the dominant hydrogeochemical processes in the hydrothermal evolution. All the hot springs show long-time water-rock interaction and significant 18O shift occurred in the Yindun area. Tritium data indicate the long-time water-rock interaction time in the hydrothermal system. According to the isotope and geochemical data, the hydrothermal systems in Yidun and Litang area may share a common deep parent geothermal liquid but receive different sources of meteoric precipitation and undergone different geochemical processes. The Yidun area have relative high reservoir equilibrium temperature (up to 230 °C) while the reservoir temperature at Litang area is relative low (up to 128 °C).

  7. Seismic tremor and gravity measurements at Inferno Crater Lake, Waimangu Geothermal Field, New Zealand

    NASA Astrophysics Data System (ADS)

    O'Brien, J. F.; Jolly, A. D.; Fournier, N.; Cole-Baker, J.; Hurst, T.; Roman, D. C.

    2011-12-01

    Volcanic crater lakes are often associated with active hydrothermal systems that induce cyclic behavior in the lake's level, temperature, and chemistry. Inferno Crater Lake, located in the Waimangu geothermal field within the Taupo Volcanic Zone (TVZ) on the North Island of New Zealand exhibits lake level fluctuations of >7m, and temperature fluctuations >40°C with a highly variable periodicity. Seismic and gravity monitoring of Inferno Lake was carried out from December, 2009 - March, 2010 and captured a full cycle of lake fluctuation. Results indicate that this cycle consisted of ~5 smaller fluctuations of ~3m in lake level followed by a larger fluctuation of ~7m. A broadband seismometer recorded strong seismic tremor in the hours leading up to each of the minor and major high stands in lake level. Spectral analysis of the tremor shows dominant frequencies in the range of ~10Hz and a fundamental harmonic frequency located in the 1Hz range. The 1Hz frequency band exhibits gliding spectral lines which increase in frequency at the end of each tremor period. Particle motion analysis of harmonic tremor waveforms indicate a ~100m upward migration of the source location from the onset of tremor until it ceases at the peak of each lake level high stand. Particle motions also indicate an azimuthal migration of the source by ~30° from the overflow outlet region of the lake toward the central vent location during the course of the tremor and lake level increase. Lake water temperature has a direct relationship with lake level and ranges between ~40°C - ~80°C. Gravity fluctuations were also continuously monitored using a Micro-g-LaCoste gPhone relative gravity meter with a 1Hz sampling rate and precision of 1 microgal. These data indicate a direct relationship between lake level and gravity showing a net increase of ~100 microgals between lake level low and high stands. A piezometer located beside the lake indicates an inflow of ground water into the subsoil during

  8. Assessment of Geothermal Resource Potential at a High-Priority Area on the Utah Testing and Training Range–South (UTTR–S)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Richard P. Smith, PhD., PG; Robert P. Breckenridge, PhD.; Thomas R. Wood, PhD.

    2012-04-01

    Field investigations conducted during 2011 support and expand the conclusion of the original Preliminary Report that discovery of a viable geothermal system is possible in the northwestern part of the Utah Testing and Training Range-South (UTTR-S), referred to henceforth as Focus Area 1. The investigations defined the southward extent of the Wendover graben into and near Focus Area 1, enhanced the understanding of subsurface conditions, and focused further geothermal exploration efforts towards the northwestern-most part of Focus Area 1. Specifically, the detailed gravity survey shows that the Wendover graben, first defined by Cook et al. (1964) for areas north ofmore » Interstate Highway 80, extends and deepens southwest-ward to the northwest corner of Focus Area 1. At its deepest point, the intersection with a northwest-trending graben there is favorable for enhanced permeability associated with intersecting faults. Processing and modeling of the gravity data collected during 2011 provide a good understanding of graben depth and distribution of faults bounding the graben and has focused the interest area of the study. Down-hole logging of temperatures in wells made available near the Intrepid, Inc., evaporation ponds, just north of Focus Area 1, provide a good understanding of the variability of thermal gradients in that area and corroborate the more extensive temperature data reported by Turk (1973) for the depth range of 300-500 m. Moderate temperature gradients in the northern part of the Intrepid area increase to much higher gradients and bottom-hole temperatures southeastward, towards graben-bounding faults, suggesting upwelling geothermal waters along those faults. Water sampling, analysis, and temperature measurements of Blue Lakes and Mosquito Willey's springs, on the western boundary of Focus Area 1, also show elevated temperatures along the graben-bounding fault system. In addition, water chemistry suggests origin of those waters in limestone rocks

  9. LakeMIP Kivu: Evaluating the representation of a large, deep tropical lake by a set of 1-dimensional lake models

    NASA Astrophysics Data System (ADS)

    Thiery, Wim; Stepanenko, Viktor; Darchambeau, François; Joehnk, Klaus; Martynov, Andrey; Mironov, Dmitrii; Perroud, Marjorie; van Lipzig, Nicole

    2013-04-01

    The African great lakes are of utmost importance for the local economy (fishing), as well as being essential to the survival of the local people. During the last decades, these lakes experienced fast changes in ecosystem structure and functioning and their future evolution is a major concern. In this study, for the first time a set of one-dimensional lake models are evaluated over East-Africa, in particular over Lake Kivu (2.28 °S; 28.98 °E). The unique limnology of meromictic Lake Kivu, with the importance of salinity and geothermal springs in a tropical high-altitude climate, presents a worthy challenge to the 1D-lake models currently involved in the Lake Model Intercomparison Project (LakeMIP). Furthermore, this experiment will serve as the basis for a future, more complex intercomparison, coupling lake models with atmospheric circulation models to analyse climate change effects on the lake. Meteorological observations from two automatic weather stations, one at Kamembe airport (Rwanda, 2003-2008), the other at ISP Bukavu (DRC, 2003-2011), are used to drive each of these models. For the evaluation, a unique dataset is used which contains over 150 temperature profiles recorded since 2002. The standard LakeMIP protocol is adapted to mirror the limnological conditions in Lake Kivu and to unify model parameters as far as possible. Since some lake models do not account for salinity and its effect upon lake stratification, two sets of simulations are performed with each model: one for the freshwater layer only (60 m) and one for the average lake depth (240 m) including salinity. Therewith, on the one hand it is investigated whether each model is able to reproduce the correct mixing regime in Lake Kivu and captures the controlling of this seasonality by the relative humidity, which constrains evaporation except during summer (JJA). On the other hand, the ability of different models to simulate salinity- and geothermal-induced effects upon deep water stratification is

  10. Geothermal characteristics of deep wells using geophysical logs in Pohang area, Korea

    NASA Astrophysics Data System (ADS)

    LIM, W.; Hamm, S. Y.; Lee, C.; Song, Y.; Kim, H.

    2016-12-01

    Pohang area displays a larger potential of geothermal energy with the highest heat flow of 83 mWm-2 in South Korea. A geothermal binary power plant with a generation capacity of 1.5MW using enhanced geothermal system (EGS) is under construction in Pohang area and will be completed until 2017. This study aims to reveal geothermal characteristics of four wells (BH-1 to BH-4 wells) of 2,383 m in depth in Pohang area, using geophysical logs. The geology of the study area is composed of tertiary mudstone of 200 - 359.1 m, tuff of 73 - 240 m, sandstone/mudstone of 46 - 907 m, rhyolite of 259 - 375 m, and andesitic volcanic breccia of 834 m in thicknesses from the surface, with granodiorite at bottom. By the result of the study, temperature and maximum electrical conductivity (EC) are 69.5°C at 1,502.6 m and 1,162 μS/cm at BH-2 well, 44.4°C at 912.3 m and 1,105 μS/cm at BH-3 well, and 82.5°C at 1,981.3 m and 3,412 μS/cm at BH-4 well. Thermal conductivity values at saturated state are 2.14 - 3.95 W/m-K (average 3.47 W/m-K) at BH-1 well and 2.36 - 3.61 W/m-K (average 2.85 W/m-K) at BH-4 well. ß (determining heat flow rate and up/down direction) values were estimated by using 1-D steady-state heat transfer equation and were determined as -0.77 - 0.99 with the geothermal gradients (Ks) of 42.5 - 46.3°C/km at BH-1 well, -3.15 - 3.05 with the Ks of 25.0 - 29.1°C/km at BH-2, -1.80 - 2.09 with the Ks of 20.0 - 23.0°C/km at BH-3 well, and -4.10 - 5.18 with the Ks of 30.2 - 39.0°C/km at BH-4 well. Most depths of all the wells showed upward heat transfer. Based on the geophysical logs, the main aquifer is located between 200 and 300 meters. KEY WORDS: Geothermal gradient, thermal conductivity, geophysical logs, ß value, heat transfer equation, Pohang area Acknowledgement This work was supported by grants from the Principal Research Fund of Korea Institute of the Geoscience and Mineral Resources (KIGAM 16-3411).

  11. Reconnaissance geologic map and mineral resource potential of the Gearhart Mountain Wilderness and Roadless Area (6225), Lake and Klamath counties, Oregon

    USGS Publications Warehouse

    Walker, George W.; Ridenour, James

    1982-01-01

    The Gearhart Mountain Wilderness, Lake and Klamath Counties, Oreg., is devoid of mines and mineral prospects and there are no known mining claims within the area. Furthermore, the results of this mineral appraisal indicate that there is little likelihood that commercial deposits of metallic minerals will be found in the area. Commercial uranium deposits, like those at the White King and Lucky Lass mines about 16 mi (~25 km) to the southeast of the wilderness, and deposits of mercury, like those south-southeast of the wilderness, are not likely to be found within the wilderness, even though all of these areas are characterized by middle and late Cenozoic intrusive and extrusive volcanic rocks. Rock of low commercial value for construction purposes is present, but better and more accessible deposits are present in adjacent regions. There is no evidence to indicate that mineral fuels are present in the area. Higher than normal heat floe characterizes the region containing Gerheart Mountain, indicating that it may have some, as yet undefined, potential for the development of geothermal energy. Data are not available to determine whether this higher than normal heat flow is meaningful in terms of a potential energy source or as a guide to possible future exploration; lack of thermal springs or other evidence of localized geothermal anomalies within the Gerhart Mountain suggest, however, that the potential for the development of geothermal energy is probably low.

  12. High geothermal heat flux measured below the West Antarctic Ice Sheet

    PubMed Central

    Fisher, Andrew T.; Mankoff, Kenneth D.; Tulaczyk, Slawek M.; Tyler, Scott W.; Foley, Neil

    2015-01-01

    The geothermal heat flux is a critical thermal boundary condition that influences the melting, flow, and mass balance of ice sheets, but measurements of this parameter are difficult to make in ice-covered regions. We report the first direct measurement of geothermal heat flux into the base of the West Antarctic Ice Sheet (WAIS), below Subglacial Lake Whillans, determined from the thermal gradient and the thermal conductivity of sediment under the lake. The heat flux at this site is 285 ± 80 mW/m2, significantly higher than the continental and regional averages estimated for this site using regional geophysical and glaciological models. Independent temperature measurements in the ice indicate an upward heat flux through the WAIS of 105 ± 13 mW/m2. The difference between these heat flux values could contribute to basal melting and/or be advected from Subglacial Lake Whillans by flowing water. The high geothermal heat flux may help to explain why ice streams and subglacial lakes are so abundant and dynamic in this region. PMID:26601210

  13. High geothermal heat flux measured below the West Antarctic Ice Sheet.

    PubMed

    Fisher, Andrew T; Mankoff, Kenneth D; Tulaczyk, Slawek M; Tyler, Scott W; Foley, Neil

    2015-07-01

    The geothermal heat flux is a critical thermal boundary condition that influences the melting, flow, and mass balance of ice sheets, but measurements of this parameter are difficult to make in ice-covered regions. We report the first direct measurement of geothermal heat flux into the base of the West Antarctic Ice Sheet (WAIS), below Subglacial Lake Whillans, determined from the thermal gradient and the thermal conductivity of sediment under the lake. The heat flux at this site is 285 ± 80 mW/m(2), significantly higher than the continental and regional averages estimated for this site using regional geophysical and glaciological models. Independent temperature measurements in the ice indicate an upward heat flux through the WAIS of 105 ± 13 mW/m(2). The difference between these heat flux values could contribute to basal melting and/or be advected from Subglacial Lake Whillans by flowing water. The high geothermal heat flux may help to explain why ice streams and subglacial lakes are so abundant and dynamic in this region.

  14. Simulating Lake-Groundwater Interactions During Decadal Climate Cycles: Accounting For Variable Lake Area In The Watershed

    NASA Astrophysics Data System (ADS)

    Virdi, M. L.; Lee, T. M.

    2009-12-01

    The volume and extent of a lake within the topo-bathymetry of a watershed can change substantially during wetter and drier climate cycles, altering the interaction of the lake with the groundwater flow system. Lake Starr and other seepage lakes in the permeable sandhills of central Florida are vulnerable to climate changes as they rely exclusively on rainfall and groundwater for inflows in a setting where annual rainfall and recharge vary widely. The groundwater inflow typically arrives from a small catchment area bordering the lake. The sinkhole origin of these lakes combined with groundwater pumping from underlying aquifers further complicate groundwater interactions. Understanding the lake-groundwater interactions and their effects on lake stage over multi-decadal climate cycles is needed to manage groundwater pumping and public expectation about future lake levels. The interdependence between climate, recharge, changing lake area and the groundwater catchment pose unique challenges to simulating lake-groundwater interactions. During the 10-year study period, Lake Starr stage fluctuated more than 13 feet and the lake surface area receded and expanded from 96 acres to 148 acres over drier and wetter years that included hurricanes, two El Nino events and a La Nina event. The recently developed Unsaturated Zone Flow (UZF1) and Lake (LAK7) packages for MODFLOW-2005 were used to simulate the changing lake sizes and the extent of the groundwater catchment contributing flow to the lake. The lake area was discretized to occupy the largest surface area at the highest observed stage and then allowed to change size. Lake cells convert to land cells and receive infiltration as receding lake area exposes the underlying unsaturated zone to rainfall and recharge. The unique model conceptualization also made it possible to capture the dynamic size of the groundwater catchment contributing to lake inflows, as the surface area and volume of the lake changed during the study

  15. STRUCTURAL CONTROLS OF THE EMERSON PASS GEOTHERMAL SYSTEM, NORTHWESTERN NEVADA: CHARACTERIZATION OF A "BLIND" SYSTEM

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson, Ryan B; Faulds, James E

    Detailed geologic analyses have elucidated the kinematics, stress state, structural controls, and past surface activity of a blind geothermal system in Emerson Pass on the Pyramid Lake Paiute Reservation, western Nevada. The Emerson Pass area resides near the boundary of the Basin and Range and Walker Lane provinces and at the western edge of a broad left step or relay ramp between the north- to north-northeast-striking, west-dipping, Fox and Lake Range normal faults. The step-over provides a structurally favorable setting for deep circulation of meteoric fluids. Strata in the area are comprised of late Miocene to Pliocene sedimentary rocks andmore » the middle Miocene Pyramid sequence mafic to intermediate volcanic rocks, all overlying Mesozoic metasedimentary and intrusive rocks. A thermal anomaly was discovered in Emerson Pass by use of 2-m temperature surveys deployed within a structurally favorable setting and proximal to surface features indicative of geothermal activity. The 2-m temperature surveys define a north-south elongate thermal anomaly that has a maximum recorded temperature of ~60°C and resides on a north- to north-northeast-striking normal fault. Although the active geothermal system is expressed solely as a soil heat anomaly, late Pleistocene travertine and tufa mounds, chalcedonic silica/calcite veins, and silica cemented Pleistocene lacustrine gravels indicate a robust geothermal system was active at the surface in the recent past. The geothermal system is controlled primarily by the broad step-over between two major range-bounding normal faults. In detail, the system likely results from enhanced permeability generated by the intersection of two oppositely dipping, southward terminating north- to north-northwest-striking (Fox Range fault) and north-northeast-striking normal faults. Structural complexity and spatial heterogeneities of the strain and stress field have developed in the step-over region, but kinematic data suggest a west

  16. Preliminary 3d depth migration of a network of 2d seismic lines for fault imaging at a Pyramid Lake, Nevada geothermal prospect

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Frary, R.; Louie, J.; Pullammanappallil, S.

    Roxanna Frary, John N. Louie, Sathish Pullammanappallil, Amy Eisses, 2011, Preliminary 3d depth migration of a network of 2d seismic lines for fault imaging at a Pyramid Lake, Nevada geothermal prospect: presented at American Geophysical Union Fall Meeting, San Francisco, Dec. 5-9, abstract T13G-07.

  17. Feasibility of geothermal space/water heating for Mammoth Lakes Village, California. Final report, September 1976--September 1977

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sims, A.V.; Racine, W.C.

    1977-12-01

    Results of a study to determine the technical, economic, and environmental feasibility of geothermal district heating for Mammoth Lakes Village, California are reported. The geothermal district heating system selected is technically feasible and will use existing technology in its design and operation. District heating can provide space and water heating energy for typical customers at lower cost than alternative sources of energy. If the district heating system is investor owned, lower costs are realized after five to six years of operation, and if owned by a nonprofit organization, after zero to three years. District heating offers lower costs than alternativesmore » much sooner in time if co-generation and/or DOE participation in system construction are included in the analysis. During a preliminary environmental assessment, no potential adverse environmental impacts could be identified of sufficient consequence to preclude the construction and operation of the proposed district heating system. A follow-on program aimed at implementing district heating in Mammoth is outlined.« less

  18. Changes in the water quality and bacterial community composition of an alkaline and saline oxbow lake used for temporary reservoir of geothermal waters.

    PubMed

    Borsodi, Andrea K; Szirányi, Barbara; Krett, Gergely; Márialigeti, Károly; Janurik, Endre; Pekár, Ferenc

    2016-09-01

    Geothermal waters exploited in the southeastern region of Hungary are alkali-hydrogen-carbonate type, and beside the high amount of dissolved salt, they contain a variety of aromatic, heteroaromatic, and polyaromatic hydrocarbons. The majority of these geothermal waters used for heating are directed into surface waters following a temporary storage in reservoir lakes. The aim of this study was to gain information about the temporal and spatial changes of the water quality as well as the bacterial community composition of an alkaline and saline oxbow lake operated as reservoir of used geothermal water. On the basis of the water physical and chemical measurements as well as the denaturing gradient gel electrophoresis (DGGE) patterns of the bacterial communities, temporal changes were more pronounced than spatial differences. During the storage periods, the inflow, reservoir water, and sediment samples were characterized with different bacterial community structures in both studied years. The 16S ribosomal RNA (rRNA) gene sequences of the bacterial strains and molecular clones confirmed the differences among the studied habitats. Thermophilic bacteria were most abundant in the geothermal inflow, whereas the water of the reservoir was dominated by cyanobacteria and various anoxygenic phototrophic prokaryotes. In addition, members of several facultative anaerobic denitrifying, obligate anaerobic sulfate-reducing and syntrophic bacterial species capable of decomposition of different organic compounds including phenols were revealed from the water and sediment of the reservoir. Most of these alkaliphilic and/or halophilic species may participate in the local nitrogen and sulfur cycles and contribute to the bloom of phototrophs manifesting in a characteristic pink-reddish discoloration of the water of the reservoir.

  19. Hydrology of the Lake Deaton and Lake Okahumpka area, Northeast Sumter County, Florida

    USGS Publications Warehouse

    Simonds, Edward P.; German, E.R.

    1980-01-01

    The Floridan aquifer in the Lake Deaton and Lake Okahumpka area is 50 to 130 feet below land surface. During the 16-year period 1963-78 lake evaporation exceeded rainfall by 0.4 inches. Drainage from Lake Deaton and its surrounding area goes into Chitty Chatty Creek and on the Hogeye Sink when the altitude of the potentiometric surface of the Floridan aquifer is low. During a higher altitude of the Floridan potentiometric surface, Hogeye Sink may discharge water; this water, along with the normal runoff, goes into Lake Okahumpka. Average lake fluctuation is 1.5 to 2.0 feet per year. Lake Deaton supports a large population of blue-green algae and Lake Okahumpka is choked with aquatic plants. The water quality of the two lakes differ, with Lake Deaton having a sodium chloride water and Lake Okahumpka having a calcium bicarbonate water. Analysis of water and bottom material samples showed that only cadmium and mercury exceeded the Florida Department of Environmental Regulation 's criteria for Class III waters; however, the amounts detected were at or slightly above the limits of the analytical method. (USGS)

  20. Using PS-InSAR to detect surface deformation in geothermal areas of West Java in Indonesia

    NASA Astrophysics Data System (ADS)

    Maghsoudi, Yasser; van der Meer, Freek; Hecker, Christoph; Perissin, Daniele; Saepuloh, Asep

    2018-02-01

    In this paper, the Persistent Scatterer InSAR (PS-InSAR) technique is applied in order to investigate the ground deformation in and around two geothermal areas in West Java, Indonesia. Two time-series of ALOS PALSAR and Sentinel-1A acquisitions, covering the period from 2007 to 2009 and 2015-2016, are analysed. The first case study examines the Wayang Windu geothermal zone where the PS-InSAR analysis provides an overview of the surface deformation around a geothermal reservoir. Uplift is observed around the injection wells in the area. The second example involves the use of the PS-InSAR technique over a more recent geothermal system in Patuha field. Again, a pattern of uplift was observed around the only available injection well in the area. Due to the dense vegetation coverage of the geothermal areas in West Java, the longer wavelength ALOS PALSAR data is provides better results by identifying a larger number of PS points. Additionally, experiments have been carried out to compare the resulting deformation with another example of the fluid migration process i.e. water extraction in Bandung basin. The potential of sentinel-1A and ALOS PALSR data are compared in all the experiments.

  1. Time-dependent seismic tomography of the Coso geothermal area, 1996-2004

    USGS Publications Warehouse

    Julian, B.R.; Foulger, G.R.

    2005-01-01

    The permanent 18-station network of three-component digital seismometers at the seismically active Coso geothermal area, California, provides high-quality microearthquake (MEQ) data that are well suited to investigating temporal variations in structure related to processes within the geothermal reservoir. A preliminary study [Julian, et al., 2003; Julian, et al., 2004] comparing data from 1996 and 2003 found significant variations in the ratio of the seismic wave-speeds, Vp/Vs, at shallow depths over this time interval. This report describes results of a more detailed study of each year from 1996 through 2004.

  2. Hydrologic data and description of a hydrologic monitoring plan for the Borax Lake area, Oregon

    USGS Publications Warehouse

    Schneider, Tiffany Rae; McFarland, William D.

    1995-01-01

    Information from field visits was used to develop a monitoring plan. The plan would include monitoring Borax Lake by measuring discharge, stage, evaporation, temperature, and specific conductance; water-quality sampling and analysis; and monitoring shallow ground-water levels near Borax Lake using shallow piezometers. Minimally, one hot spring in North Borax Lake Spring Group 1 would be monitored for temperature and specific conductance and sampled for water-quality analysis. In addition, two flowing wells would be monitored for water levels, temperature, specific conductance, and discharge and sampled for water-quality analysis. The construction characteristics of these wells must be verified before long-term data collection begins. In the future, it may be helpful to monitor shallow and (or) deep observation wells drilled into the thermal aquifer to understand the possible effects of geothermal development on Borax Lake and nearby springs.

  3. Mechanisms influencing changes in lake area in Alaskan boreal forest

    USGS Publications Warehouse

    Roach, Jennifer K.; Griffith, Brad; Verbyla, David; Jones, Jeremy B.

    2011-01-01

    During the past ∼50 years, the number and area of lakes have declined in several regions in boreal forests. However, there has been substantial finer-scale heterogeneity; some lakes decreased in area, some showed no trend, and others increased. The objective of this study was to identify the primary mechanisms underlying heterogeneous trends in closed-basin lake area. Eight lake characteristics (δ18O, electrical conductivity, surface : volume index, bank slope, floating mat width, peat depth, thaw depth at shoreline, and thaw depth at the forest boundary) were compared for 15 lake pairs in Alaskan boreal forest where one lake had decreased in area since ∼1950, and the other had not. Mean differences in characteristics between paired lakes were used to identify the most likely of nine mechanistic scenarios that combined three potential mechanisms for decreasing lake area (talik drainage, surface water evaporation, and terrestrialization) with three potential mechanisms for nondecreasing lake area (subpermafrost groundwater recharge through an open talik, stable permafrost, and thermokarst). A priori expectations of the direction of mean differences between decreasing and nondecreasing paired lakes were generated for each scenario. Decreasing lakes had significantly greater electrical conductivity, greater surface : volume indices, shallower bank slopes, wider floating mats, greater peat depths, and shallower thaw depths at the forest boundary. These results indicated that the most likely scenario was terrestrialization as the mechanism for lake area reduction combined with thermokarst as the mechanism for nondecreasing lake area. Terrestrialization and thermokarst may have been enhanced by recent warming which has both accelerated permafrost thawing and lengthened the growing season, thereby increasing plant growth, floating mat encroachment, transpiration rates, and the accumulation of organic matter in lake basins. The transition to peatlands associated

  4. Geohydrology, geochemistry, geothermal potency of Rianiate Toba Lake North Sumatera

    NASA Astrophysics Data System (ADS)

    Nainggolan, Juliper; Sitepu, Cristin; Pardede, Sanggam; Diantoro, Markus

    2017-09-01

    This research was performed to determine the potency of Rianiate’s geothermal an alternative of energy source and determine the types of geothermal that was begun with the position’s measurement by using GPS (Global Position System), and then the direct observation of chemical and physical properties such as pH, surface’s temperature, color etc. The following steps were taking sample in four different springs indicated by spring 1, spring 2, spring 3, and spring 4. The chemical nature was measured by titrimetry method by using AAS, XRD, and gas Chromathology. The calculating of temperature of subsurface has done by using geothermometer and sequentially followed by geothermal potency’s calculation. The position of four springs are located about N: 02° 31,852’ and E: 098° 44. 021’ where were average height from sea’s level is 958 m. The highest surface’s temperature is 80 °C and the temperature under soil is about 130.5 °C described the average of geothermal. The calculation of content of chloride, sulfate, bicarbonations revealed that the water can be categorized as chloride type. The trilateral diagram Na/1000 - K/100 - √Mg of hot water is in the regime of immature water. From the calculation of Indonesia’s Standardized Geotherm, it was obtained that the estimated reservoir potency of Rianiate geotherm is 2,68 MWe.

  5. Association of Cancer Incidence and Duration of Residence in Geothermal Heating Area in Iceland: An Extended Follow-Up

    PubMed Central

    Kristbjornsdottir, Adalbjorg; Aspelund, Thor; Rafnsson, Vilhjalmur

    2016-01-01

    Background Residents of geothermal areas have higher incidence of non-Hodgkin’s lymphoma, breast cancer, prostate cancer, and kidney cancers than others. These populations are exposed to chronic low-level ground gas emissions and various pollutants from geothermal water. The aim was to assess whether habitation in geothermal areas and utilisation of geothermal water is associated with risk of cancer according to duration of residence. Methods The cohort obtained from the census 1981 was followed to the end of 2013. Personal identifier was used in record linkage with nation-wide emigration, death, and cancer registries. The exposed population, defined by community codes, was located on young bedrock and had utilised geothermal water supply systems since 1972. Two reference populations were located by community codes on older bedrock or had not utilised geothermal water supply systems for as long a period as had the exposed population. Adjusted hazard ratio (HR), 95% confidence intervals (CI) non-stratified and stratified on cumulative years of residence were estimated in Cox-model. Results The HR for all cancer was 1.21 (95% CI 1.12–1.30) as compared with the first reference area. The HR for pancreatic cancer was 1.93 (1.22–3.06), breast cancer, 1.48 (1.23–1.80), prostate cancer 1.47 (1.22–1.77), kidney cancer 1.46 (1.03–2.05), lymphoid and haematopoietic tissue 1.54 (1.21–1.97), non-Hodgkin´s lymphoma 2.08 (1.38–3.15) and basal cell carcinoma of the skin 1.62 (1.35–1.94). Positive dose-response relationship was observed between incidence of cancers and duration of residence, and between incidence of cancer and degree of geothermal/volcanic activity in the comparison areas. Conclusions The higher cancer incidence in geothermal areas than in reference areas is consistent with previous findings. As the dose-response relationships were positive between incidence of cancers and duration of residence, it is now more urgent than before to investigate

  6. Association of Cancer Incidence and Duration of Residence in Geothermal Heating Area in Iceland: An Extended Follow-Up.

    PubMed

    Kristbjornsdottir, Adalbjorg; Aspelund, Thor; Rafnsson, Vilhjalmur

    2016-01-01

    Residents of geothermal areas have higher incidence of non-Hodgkin's lymphoma, breast cancer, prostate cancer, and kidney cancers than others. These populations are exposed to chronic low-level ground gas emissions and various pollutants from geothermal water. The aim was to assess whether habitation in geothermal areas and utilisation of geothermal water is associated with risk of cancer according to duration of residence. The cohort obtained from the census 1981 was followed to the end of 2013. Personal identifier was used in record linkage with nation-wide emigration, death, and cancer registries. The exposed population, defined by community codes, was located on young bedrock and had utilised geothermal water supply systems since 1972. Two reference populations were located by community codes on older bedrock or had not utilised geothermal water supply systems for as long a period as had the exposed population. Adjusted hazard ratio (HR), 95% confidence intervals (CI) non-stratified and stratified on cumulative years of residence were estimated in Cox-model. The HR for all cancer was 1.21 (95% CI 1.12-1.30) as compared with the first reference area. The HR for pancreatic cancer was 1.93 (1.22-3.06), breast cancer, 1.48 (1.23-1.80), prostate cancer 1.47 (1.22-1.77), kidney cancer 1.46 (1.03-2.05), lymphoid and haematopoietic tissue 1.54 (1.21-1.97), non-Hodgkin´s lymphoma 2.08 (1.38-3.15) and basal cell carcinoma of the skin 1.62 (1.35-1.94). Positive dose-response relationship was observed between incidence of cancers and duration of residence, and between incidence of cancer and degree of geothermal/volcanic activity in the comparison areas. The higher cancer incidence in geothermal areas than in reference areas is consistent with previous findings. As the dose-response relationships were positive between incidence of cancers and duration of residence, it is now more urgent than before to investigate the chemical and physical content of the geothermal water

  7. Advanced Low Temperature Geothermal Power Cycles (The ENTIV Organic Project) Final Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mugerwa, Michael

    2015-11-18

    Feasibility study of advanced low temperature thermal power cycles for the Entiv Organic Project. Study evaluates amonia-water mixed working fluid energy conversion processes developed and licensed under Kalex in comparison with Kalina cycles. Both cycles are developed using low temperature thermal resource from the Lower Klamath Lake Geothermal Area. An economic feasibility evaluation was conducted for a pilot plant which was deemed unfeasible by the Project Sponsor (Entiv).

  8. Three dimensional images of geothermal systems: local earthquake P-wave velocity tomography at the Hengill and Krafla geothermal areas, Iceland, and The Geysers, California

    USGS Publications Warehouse

    Julian, B.R.; Prisk, A.; Foulger, G.R.; Evans, J.R.; ,

    1993-01-01

    Local earthquake tomography - the use of earthquake signals to form a 3-dimensional structural image - is now a mature geophysical analysis method, particularly suited to the study of geothermal reservoirs, which are often seismically active and severely laterally inhomogeneous. Studies have been conducted of the Hengill (Iceland), Krafla (Iceland) and The Geysers (California) geothermal areas. All three systems are exploited for electricity and/or heat production, and all are highly seismically active. Tomographic studies of volumes a few km in dimension were conducted for each area using the method of Thurber (1983).

  9. Crustal structure in Tengchong Volcano-Geothermal Area, western Yunnan, China

    NASA Astrophysics Data System (ADS)

    Wang, Chun-Yong; Huangfu, Gang

    2004-02-01

    Based upon the deep seismic sounding profiles carried out in the Tengchong Volcano-Geothermal Area (TVGA), western Yunnan Province of China, a 2-D crustal P velocity structure is obtained by use of finite-difference inversion and forward travel-time fitting method. The crustal model shows that a low-velocity anomaly zone exists in the upper crust, which is related to geothermal activity. Two faults, the Longling-Ruili Fault and Tengchong Fault, on the profile extend from surface to the lower crust and the Tengchong Fault likely penetrates the Moho. Moreover, based on teleseismic receiver functions on a temporary seismic network, S-wave velocity structures beneath the geothermal field show low S-wave velocity in the upper crust. From results of geophysical survey, the crust of TVGA is characterized by low P-wave and S-wave velocities, low resistivity, high heat-flow value and low Q. The upper mantle P-wave velocity is also low. This suggests presence of magma in the crust derived from the upper mantle. The low-velocity anomaly in upper crust may be related to the magma differentiation. The Tengchong volcanic area is located on the northeast edge of the Indian-Eurasian plate collision zone, away from the eastern boundary of the Indian plate by about 450 km. Based on the results of this paper and related studies, the Tengchong volcanoes can be classified as plate boundary volcanoes.

  10. Sensitivity Studies of 3D Reservoir Simulation at the I-Lan Geothermal Area in Taiwan Using TOUGH2

    NASA Astrophysics Data System (ADS)

    Kuo, C. W.; Song, S. R.

    2014-12-01

    A large scale geothermal project conducted by National Science Council is initiated recently in I-Lan south area, northeastern Taiwan. The goal of this national project is to generate at least 5 MW electricity from geothermal energy. To achieve this goal, an integrated team which consists of various specialties are held together to investigate I-Lan area comprehensively. For example, I-Lan geological data, petrophysical analysis, seismicity, temperature distribution, hydrology, geochemistry, heat source study etc. were performed to build a large scale 3D conceptual model of the geothermal potential sites. In addition, not only a well of 3000m deep but also several shallow wells are currently drilling to give us accurate information about the deep underground. According to the current conceptual model, the target area is bounded by two main faults, Jiaosi and Choshui faults. The geothermal gradient measured at one drilling well (1200m) is about 49.1˚C/km. The geothermal reservoir is expected to occur at a fractured geological formation, Siling sandstone layer. The preliminary results of this area from all the investigations are used as input parameters to create a realistic numerical reservoir model. This work is using numerical simulator TOUGH2/EOS1 to study the geothermal energy potential in I-Lan area. Once we can successfully predict the geothermal energy potential in this area and generate 5 MW electricity, we can apply the similar methodology to the other potential sites in Taiwan, and therefore increase the percentage of renewable energy in the generation of electricity. A large scale of three-dimensional subsurface geological model is built mainly based on the seismic exploration of the subsurface structure and well log data. The dimensions of the reservoir model in x, y, and z coordinates are 20x10x5 km, respectively. Once the conceptual model and the well locations are set up appropriately based on the field data, sensitivity studies on production and

  11. Monitoring ground-surface heating during expansion of the Casa Diablo production well field at Mammoth Lakes, California

    USGS Publications Warehouse

    Bergfeld, D.; Vaughan, R. Greg; Evans, William C.; Olsen, Eric

    2015-01-01

    The Long Valley hydrothermal system supports geothermal power production from 3 binary plants (Casa Diablo) near the town of Mammoth Lakes, California. Development and growth of thermal ground at sites west of Casa Diablo have created concerns over planned expansion of a new well field and the associated increases in geothermal fluid production. To ensure that all areas of ground heating are identified prior to new geothermal development, we obtained high-resolution aerial thermal infrared imagery across the region. The imagery covers the existing and proposed well fields and part of the town of Mammoth Lakes. Imagery results from a predawn flight on Oct. 9, 2014 readily identified the Shady Rest thermal area (SRST), one of two large areas of ground heating west of Casa Diablo, as well as other known thermal areas smaller in size. Maximum surface temperatures at 3 thermal areas were 26–28 °C. Numerous small areas with ground temperatures >16 °C were also identified and slated for field investigations in summer 2015. Some thermal anomalies in the town of Mammoth Lakes clearly reflect human activity.Previously established projects to monitor impacts from geothermal power production include yearly surveys of soil temperatures and diffuse CO2 emissions at SRST, and less regular surveys to collect samples from fumaroles and gas vents across the region. Soil temperatures at 20 cm depth at SRST are well correlated with diffuse CO2 flux, and both parameters show little variation during the 2011–14 field surveys. Maximum temperatures were between 55–67 °C and associated CO2 discharge was around 12–18 tonnes per day. The carbon isotope composition of CO2 is fairly uniform across the area ranging between –3.7 to –4.4 ‰. The gas composition of the Shady Rest fumarole however has varied with time, and H2S concentrations in the gas have been increasing since 2009.

  12. View of the Salt Lake City, Utah area

    NASA Technical Reports Server (NTRS)

    1973-01-01

    An oblique view of the Salt Lake City, Utah area as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. Approximately two-thirds of the Great Salt Lake is in view. The smaller body of water south of Salt Lake City is Utah Lake. The Wasatch Range is on the east side of the Great Salt Lake.

  13. Geotherm: the U.S. geological survey geothermal information system

    USGS Publications Warehouse

    Bliss, J.D.; Rapport, A.

    1983-01-01

    GEOTHERM is a comprehensive system of public databases and software used to store, locate, and evaluate information on the geology, geochemistry, and hydrology of geothermal systems. Three main databases address the general characteristics of geothermal wells and fields, and the chemical properties of geothermal fluids; the last database is currently the most active. System tasks are divided into four areas: (1) data acquisition and entry, involving data entry via word processors and magnetic tape; (2) quality assurance, including the criteria and standards handbook and front-end data-screening programs; (3) operation, involving database backups and information extraction; and (4) user assistance, preparation of such items as application programs, and a quarterly newsletter. The principal task of GEOTHERM is to provide information and research support for the conduct of national geothermal-resource assessments. The principal users of GEOTHERM are those involved with the Geothermal Research Program of the U.S. Geological Survey. Information in the system is available to the public on request. ?? 1983.

  14. Mountain home known geothermal resource area: an environmental analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Spencer, S.G.; Russell, B.F.

    1979-09-01

    The Mountain Home KGRA encompasses an area of 3853 hectares (ha) at the foot of the Mount Bennett Hills in Elmore County, Idaho. The site is associated with an arid climate and high winds that generate an acute dust problem. The KGRA lies adjacent to the northwest-southeast trending fault zone that reflects the northern boundary of the western Snake River Plain graben. Data indicate that a careful analysis of the subsidence potential is needed prior to extensive geothermal development. Surface water resources are confined to several small creeks. Lands are utilized for irrigated farmlands and rangeland for livestock. There aremore » no apparent soil limitations to geothermal development. Sage grouse and mule deer are the major species of concern. The potential of locating significant heritage resources other than the Oregon Trail or the bathhouse debris appears to be relatively slight.« less

  15. 33 CFR 334.820 - Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill. 334.820 Section 334.820 Navigation and Navigable... REGULATIONS § 334.820 Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill. (a...

  16. 33 CFR 334.820 - Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill. 334.820 Section 334.820 Navigation and Navigable... REGULATIONS § 334.820 Lake Michigan; naval restricted area, U.S. Naval Training Center, Great Lakes, Ill. (a...

  17. Raft River Geothermal Area Data Models - Conceptual, Logical and Fact Models

    DOE Data Explorer

    Cuyler, David

    2012-07-19

    Conceptual and Logical Data Model for Geothermal Data Concerning Wells, Fields, Power Plants and Related Analyses at Raft River a. Logical Model for Geothermal Data Concerning Wells, Fields, Power Plants and Related Analyses, David Cuyler 2010 b. Fact Model for Geothermal Data Concerning Wells, Fields, Power Plants and Related Analyses, David Cuyler 2010 Derived from Tables, Figures and other Content in Reports from the Raft River Geothermal Project: "Technical Report on the Raft River Geothermal Resource, Cassia County, Idaho," GeothermEx, Inc., August 2002. "Results from the Short-Term Well Testing Program at the Raft River Geothermal Field, Cassia County, Idaho," GeothermEx, Inc., October 2004.

  18. Efficiency of temporary storage of geothermal waters in a lake system: Monitoring the changes of water quality and bacterial community structures.

    PubMed

    Szirányi, Barbara; Krett, Gergely; Kosáros, Tünde; Janurik, Endre; Pekár, Ferenc; Márialigeti, Károly; Borsodi, Andrea K

    2017-12-01

    Disposal of used geothermal waters in Hungary often means temporary storage in reservoir lakes to reduce temperature and improve water quality. In this study, the physical and chemical properties and changes in the bacterial community structure of a reservoir lake system in southeast region of Hungary were monitored and compared through 2 years, respectively. The values of biological oxygen demand, concentrations of ammonium ion, total inorganic nitrogen, total phosphorous, and total phenol decreased, whereas oxygen saturation, total organic nitrogen, pH, and conductivity increased during the storage period. Bacterial community structure of water and sediment samples was compared by denaturing gradient gel electrophoresis (DGGE) following the amplification of the 16S rRNA gene. According to the DGGE patterns, greater seasonal than spatial differences of bacterial communities were revealed in both water and sediment of the lakes. Representatives of the genera Arthrospira and Anabaenopsis (cyanobacteria) were identified as permanent and dominant members of the bacterial communities.

  19. Preliminary determination of geothermal working area based on Thermal Infrared and Synthetic Aperture Radar (SAR) remote sensing

    NASA Astrophysics Data System (ADS)

    Agoes Nugroho, Indra; Kurniawahidayati, Beta; Syahputra Mulyana, Reza; Saepuloh, Asep

    2017-12-01

    Remote sensing is one of the methods for geothermal exploration. This method can be used to map the geological structures, manifestations, and predict the geothermal potential area. The results from remote sensing were used as guidance for the next step exploration. Analysis of target in remote sensing is an efficient method to delineate geothermal surface manifestation without direct contact to the object. The study took a place in District Merangin, Jambi Province, Indonesia. The area was selected due to existing of Merangin volcanic complex composed by Mounts Sumbing and Hulunilo with surface geothermal manifestations presented by hot springs and hot pools. The location of surface manifestations could be related with local and regional structures of Great Sumatra Fault. The methods used in this study were included identification of volcanic products, lineament extraction, and lineament density quantification. The objective of this study is to delineate the potential zones for sitting the geothermal working site based on Thermal Infrared and Synthetic Aperture Radar (SAR) sensors. The lineament-related to geological structures, was aimed for high lineament density, is using ALOS - PALSAR (Advanced Land Observing Satellite - The Phased Array type L-band Synthetic Aperture Radar) level 1.1. The Normalized Difference Vegetation Index (NDVI) analysis was used to predict the vegetation condition using Landsat 8 OLI-TIRS (The Operational Land Imager - Thermal Infrared Sensor). The brightness temperature was extracted from TIR band to estimate the surface temperature. Geothermal working area identified based on index overlay method from extracted parameter of remote sensing data was located at the western part of study area (Graho Nyabu area). This location was identified because of the existence of high surface temperature about 30°C, high lineament density about 4 - 4.5 km/km2 and low NDVI values less than 0.3.

  20. Hydrothermal circulation at the world's highest lake? An environmental study of the Licancabur Volcano crater lake as a terrestrial analog to martian paleolakes.

    NASA Astrophysics Data System (ADS)

    Hock, A. N.; Cabrol, N. A.; Grin, E. A.; Fike, D. A.; Paige, D. A.; 2002 Licancabur Expedition Team

    2003-04-01

    At approximately 6000 meters above sea level, the crater of Licancabur Volcano (22 50'S, 67 53'W) houses the highest lake in the world, yet remains largely unexplored. In particular, the physical environment of the lake--particularly its stability and any remaining geothermal activity--is not well understood. Using a model for the temperature of maximum density for freshwater as a function of pressure (Eklund), we calculated that the bottom water temperature of the summit lake should be approximately 4 C. However, Leach et al. measured the water temperature at depth to be 6 C. This discrepancy, as well as the observation that the lake remains liquid for much of the year despite sub freezing air temperatures, suggests that there may be a heat source supporting the lake's temperature and biological community. We present the results of two studies here: the goal of this work is to understand the role of geothermal fluid input to the summit lake in terms of energy balance, the physical constraints on endemic biology, and the analogy to ancient martian hydrothermal systems (e.g. volcanic lakes, crater lakes, hot springs, etc.). First, we present physical data from the lake in a new model of energy balance. In situ measurements of pH, temperature, and total dissolved solids suggest that the Licancabur summit lake is a ¨low-activity¨ (as per Pasternack and Varekamp) lake with a diffuse geothermal fluid input. Secondly, mass spectrometry and ion chromatography were used to study water samples taken from the summit lake, as well as two local lagunas and several geothermal springs at the base of the volcano. The case for a hydrothermal system in the summit lake is further strengthened here by preliminary ion chromatography results, which show elevated concentrations of sulfate and chloride with respect to local meteoric waters. Understanding the relationship between the physical environment and biotic community remains the mainstay for future work on this project in an

  1. Structural Controls of the Emerson Pass Geothermal System, Washoe County, Nevada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson, Ryan B; Faulds, James E

    We have conducted a detailed geologic study to better characterize a blind geothermal system in Emerson Pass on the Pyramid Lake Paiute Tribe Reservation, western Nevada. A thermal anomaly was discovered in Emerson Pass by use of 2 m temperature surveys deployed within a structurally favorable setting and proximal to surface features indicative of geothermal activity. The anomaly lies at the western edge of a broad left step at the northeast end of Pyramid Lake between the north- to north-northeast-striking, west-dipping, Fox and Lake Range normal faults. The 2-m temperature surveys have defined a N-S elongate thermal anomaly that hasmore » a maximum recorded temperature of ~60°C and resides on a north- to north-northeaststriking fault. Travertine mounds, chalcedonic silica veins, and silica cemented Pleistocene lacustrine gravels in Emerson Pass indicate a robust geothermal system active at the surface in the recent past. Structural complexity and spatial heterogeneities of the strain and stress field have developed in the step-over region, but kinematic data suggest a WNW-trending (~280° azimuth) extension direction. The geothermal system is likely hosted in Emerson Pass as a result of enhanced permeability generated by the intersection of two oppositely dipping, southward terminating north- to north-northwest-striking (Fox Range fault) and northnortheast- striking faults.« less

  2. Geothermal Exploration in Hot Springs, Montana

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Toby McIntosh, Jackola Engineering

    2012-09-26

    The project involves drilling deeper in the Camp Aqua well dri lled in June 1982 as part of an effort to develop an ethanol plant. The purpose of the current drill ing effort is to determine if water at or above 165°F exists for the use in low temperature resource power generation. Previous geothermal resource study efforts in and around Hot Springs , MT and the Camp Aqua area (NE of Hot Springs) have been conducted through the years. A confined gravel aquifer exists in deep alluvium overlain by approximately 250 of si lt and c lay deposits from Glacialmore » Lake Missoula. This gravel aquifer overlies a deeper bedrock aquifer. In the Camp Aqua area several wel l s exist in the gravel aquifer which receives hot water f rom bedrock fractures beneath the area. Prior to this exploration, one known well in the Camp Aqua area penetrated into the bedrock without success in intersecting fractures transporting hot geothermal water. The exploration associated with this project adds to the physical knowledge database of the Camp Aqua area. The dri l l ing effort provides additional subsurface information that can be used to gain a better understanding of the bedrock formation that i s leaking hot geothermal water into an otherwise cold water aquifer. The exi s t ing well used for the explorat ion is located within the center of the hottest water within the gravel aquifer. This lent i t sel f as a logical and economical location to continue the exploration within the existing well. Faced with budget constraints due to unanticipated costs, changing dril l ing techniques stretched the limited project resources to maximize the overa l l well depth which f e l l short of original project goals. The project goal of finding 165°F or hotter water was not achieved; however the project provides additional information and understanding of the Camp Aqua area that could prove valuable in future exploration efforts« less

  3. Geophysical Investigation of the Lake City Fault Zone, Surprise Valley, California, and Implications for Geothermal Circulation

    NASA Astrophysics Data System (ADS)

    McPhee, D. K.; Glen, J. M.; Egger, A. E.; Chuchel, B. A.

    2009-12-01

    New audiomagnetotelluric (AMT), gravity, and magnetic data were collected in Surprise Valley, northwestern Basin and Range, in order to investigate the role that the Lake City Fault Zone (LCFZ) may play in controlling geothermal circulation in the area. Surprise Valley hosts an extensional geothermal system currently undergoing exploration for development on several scales. The focus of much of that exploration has been the LCFZ, a set of NW-SE-trending structures that has been suggested on the basis of (1) low-relief scarps in the NW portion of the zone, (2) dissolved mineral-rich groundwater chemistry along its length, and (3) parallelism with a strong regional fabric that includes the Brothers Fault Zone. The LCFZ extends across the valley at a topographic high, intersecting the N-S-trending basin-bounding faults where major hot springs occur. This relationship suggests that the LCFZ may be a zone of permeability for flow of hydrothermal fluids. Previous potential field data indicate that there is no vertical offset along this fault zone, and little signature at all in either the gravity or magnetic data; along with the lack of surface expression along most of its length, the subsurface geometry of the LCFZ and its influence on geothermal fluid circulation remains enigmatic. The LCFZ therefore provides an ideal opportunity to utilize AMT data, which measures subsurface resistivity and therefore - unlike potential field data - is highly sensitive to the presence of saline fluids. AMT data and additional gravity and magnetic data were collected in 2009 along 3 profiles perpendicular to the LCFZ in order to define the subsurface geometry and conductivity of the fault zone down to depths of ~ 500 m. AMT soundings were collected using the Geometrics Stratagem EH4 system, a four channel, natural and controlled-source tensor system recording in the range of 10 to 92,000 Hz. To augment the low signal in the natural field a transmitter of two horizontal-magnetic dipoles

  4. Geothermal Conceptual Model in Earthquake Swarm Area: Constrains from Physical Properties of Supercritical Fluids and Dissipative Theory

    NASA Astrophysics Data System (ADS)

    Wang, S. C.; Lee, C. S.

    2016-12-01

    In recent five years, geothermal energy became one of the most prosperous renewable energy in the world, but produces only 0.5% of the global electricity. Why this great potential of green energy cannot replace the fuel and nuclear energy? The necessity of complicated exploration procedures and precious experts in geothermal field is similar to that of the oil and gas industry. The Yilan Plain (NE Taiwan) is one of the hot area for geothermal development and research in the second phase of National Energy Program (NEP-II). The geological and geophysical studies of the area indicate that the Yilan Plain is an extension of the Okinawa Trough back arc rifting which provide the geothermal resource. Based on the new constrains from properties of supercritical fluids and dissipative structure theory, the geophysical evidence give confident clues on how the geothermal system evolved at depth. The geothermal conceptual model in NEP-II indicates that the volcanic intrusion under the complicate fault system is possibly beneath the Yilan Plain. However, the bottom temperature of first deep drilling and geochemical evidence in NEP-II imply no volcanic intrusion. In contrast, our results show that seismic activities in geothermal field observed self-organization, and are consistent with the brittle-ductile / brittle-plastic transition, which indicates that supercritical fluids triggered earthquake swarms. The geothermal gradient and geochemical anomalies in Yilan Plain indicate an open system far from equilibrium. Mantle and crust exchange energy and materials through supercritical fluids to generate a dissipative structure in geothermal fields and promote water-rock interactions and fractures. Our initial studies have suggested a dissipative structure of geothermal system that could be identified by geochemical and geophysical data. The key factor is the tectonic setting that triggered supercritical fluids upwelling from deep (possibly from the mantle or the upper crust). Our

  5. Environmental analysis of geopressured-geothermal prospect areas, De Witt and Colorado counties, Texas. Final report, March 1 - August 31, 1979

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gustavson, T.C.; Reeder, F.S.; Badger, E.A.

    Information collected and analyzed for a preliminary environmental analysis of geopressured geothermal prospect areas in Colorado and DeWitt Counties, Texas is presented. Specific environmental concerns for each geopressured geothermal prospect area are identified and discussed. Approximately 218 km/sup 2/(85 mi/sup 2/) were studied in the vicinity of each prospect area to: (1) conduct an environmental analysis to identify more and less suited areas for geopressured test wells; and (2) provide an environmental data base for future development of geopressured geothermal energy resources. A series of maps and tables are included to illustrate environmental characteristics including: geology, water resources, soils, currentmore » land use, vegetation, wildlife, and meteorological characteristics, and additional relevant information on cultural resources, power- and pipelines, and regulatory agencies. A series of transparent overlays at the scale of the original mapping has also been produced for the purposes of identifying and ranking areas of potential conflict between geopressured geothermal development and environmental characteristics. The methodology for ranking suitability of areas within the two prospect areas is discussed in the appendix. (MHR)« less

  6. GEOTHERM Data Set

    DOE Data Explorer

    DeAngelo, Jacob

    1983-01-01

    GEOTHERM is a comprehensive system of public databases and software used to store, locate, and evaluate information on the geology, geochemistry, and hydrology of geothermal systems. Three main databases address the general characteristics of geothermal wells and fields, and the chemical properties of geothermal fluids; the last database is currently the most active. System tasks are divided into four areas: (1) data acquisition and entry, involving data entry via word processors and magnetic tape; (2) quality assurance, including the criteria and standards handbook and front-end data-screening programs; (3) operation, involving database backups and information extraction; and (4) user assistance, preparation of such items as application programs, and a quarterly newsletter. The principal task of GEOTHERM is to provide information and research support for the conduct of national geothermal-resource assessments. The principal users of GEOTHERM are those involved with the Geothermal Research Program of the U.S. Geological Survey.

  7. Geology and surface geochemistry of the Roosevelt Springs Known Geothermal Resource Area, Utah

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lovell, J.S.; Meyer, W.T.; Atkinson, D.J.

    1980-01-01

    Available data on the Roosevelt area were synthesized to determine the spatial arrangement of the rocks, and the patterns of mass and energy flow within them. The resulting model lead to a new interpretation of the geothermal system, and provided ground truth for evaluating the application of soil geochemistry to exploration for concealed geothermal fields. Preliminary geochemical studies comparing the surface microlayer to conventional soil sampling methods indicated both practical and chemical advantages for the surface microlayer technique, which was particularly evident in the case of As, Sb and Cs. Subsequent multi-element analyses of surface microlayer samples collected over anmore » area of 100 square miles were processed to produce single element contour maps for 41 chemical parameters. Computer manipulation of the multi-element data using R-mode factor analysis provided the optimum method of interpretation of the surface microlayer data. A trace element association of As, Sb and Cs in the surface microlayer provided the best indication of the leakage of geothermal solutions to the surface, while regional mercury trends may reflect the presence of a mercury vapour anomaly above a concealed heat source.« less

  8. Lost Lake Research Natural Area: guidebook supplement 48

    Treesearch

    Reid Schuller; Bryan Wender

    2016-01-01

    This guidebook describes major biological and physical attributes of the 155-ha (384-ac) Lost Lake Research Natural Area (RNA), in Jackson County, Oregon. The RNA has been designated because it contains examples of a landslide-dammed lake; and a low-elevation lake with aquatic beds and fringing marsh, surrounded by mixed-conifer forest (ONHAC 2010).

  9. Geochemistry of thermal fluids in NW Honduras: New perspectives for exploitation of geothermal areas in the southern Sula graben

    NASA Astrophysics Data System (ADS)

    Capaccioni, Bruno; Franco, Tassi; Alberto, Renzulli; Orlando, Vaselli; Marco, Menichetti; Salvatore, Inguaggiato

    2014-06-01

    The results of a geochemical survey on thermal waters and, for the first time for this site, gas discharges in five geothermal sites (Azacualpa "La Cueva", Río Ulua, Río Gualcarque, El Olivar and Laguna de Agua Caliente) in NW Honduras are here presented and discussed. El Olivar and Laguna de Agua Caliente, in the southern part of the Sula graben are very close to a Quaternary basaltic field, whereas Azacualpa "La Cueva", Río Ulua and Río Gualcarque, located to the southwest of the Yojoa Lake, direcly emerge from the Cretaceous limestone deposits. The measured temperatures range between 37.5 and 104.8 °C. "Mature", alkaline, Na-SO4 thermal waters discharge from Azacualpa "La Cueva", while those from El Olivar and Laguna de Agua Caliente are "immature" and show a Na-HCO3 composition. Chemical equilibria of waters and gases from the Azacualpa "La Cueva" thermal springs indicate temperatures ranging from 150 to 200 °C. Conversely, gas discharges from El Olivar and Laguna de Agua Caliente have attained a partial chemical equilibrium in the liquid phase at slightly higher temperatures (200-250 °C), although gas-gas faster reactions involving CO seem to be adjusted in an isothermally separated vapor phase. Unlike Azacualpa, SiO2 geothermometer at El Olivar and Laguna de Agua Caliente indicates equilibrium temperatures for the liquid phase much lower than those calculated for the gas phase (≤ 120 °C). We conclude that thermal waters from the Azacualpa area likely represent the direct emergence of a water dominated reservoir having temperatures ≤ 150-200 °C. By contrast, at El Olivar and Laguna de Agua Caliente hot springs are supplied by a boiling shallow aquifer fed by a vapor phase rising from a steam-dominated zone. The above geochemical model is consistent with a geothermal reservoir hosted within the Cretaceous carbonate sequences of the Yojoa Group in the whole investigated sites. The reservoir extensively crops out in the Azacualpa area whereas the

  10. Mortality of populations residing in geothermal areas of Tuscany during the period 2003-2012.

    PubMed

    Bustaffa, Elisa; Minichilli, Fabrizio; Nuvolone, Daniela; Voller, Fabio; Cipriani, Francesco; Bianchi, Fabrizio

    2017-01-01

    The limited scientific knowledge on the relationship between exposure and health effects in relation to geothermal activity motivated an epidemiologic investigation of Tuscan geothermal area. This study aims at describing mortality of populations living in Tuscan municipalities in the period 2003-2012. Sixteen municipalities were included in the study area: eight in the northern and eight in the southern area. Mortality data come from the Regional Mortality Registry of Tuscany. Fifty-four causes of death, considered of interest for population health status or consistent with "Project SENTIERI" criteria, are analyzed. Results show a worse mortality profile in the southern area, especially in males, for whom excesses of all cancers and some causes of cancer emerge, while in the northern area an excess of cerebrovascular diseases among females merits attention. Further and more appropriate studies are needed to clarify the etiology of some diseases and to better assess a potential cause-effect relationship.

  11. A framework for profiling a lake's riparian area development potential

    Treesearch

    Pamela J. Jakes; Ciara Schlichting; Dorothy H. Anderson

    2003-01-01

    Some of the greatest challenges for managing residential development occur at the interface between the terrestrial and aquatic ecosystems -in a lake`s riparian area. Land use planners need a framework they can use to identify development hotspots, areas were the next push for development will most likely occur. Lake riparian development profiles provide a framework...

  12. Divergence of gastropod life history in contrasting thermal environments in a geothermal lake.

    PubMed

    Johansson, M P; Ermold, F; Kristjánsson, B K; Laurila, A

    2016-10-01

    Experiments using natural populations have provided mixed support for thermal adaptation models, probably because the conditions are often confounded with additional environmental factors like seasonality. The contrasting geothermal environments within Lake Mývatn, northern Iceland, provide a unique opportunity to evaluate thermal adaptation models using closely located natural populations. We conducted laboratory common garden and field reciprocal transplant experiments to investigate how thermal origin influences the life history of Radix balthica snails originating from stable cold (6 °C), stable warm (23 °C) thermal environments or from areas with seasonal temperature variation. Supporting thermal optimality models, warm-origin snails survived poorly at 6 °C in the common garden experiment and better than cold-origin and seasonal-origin snails in the warm habitat in the reciprocal transplant experiment. Contrary to thermal adaptation models, growth rate in both experiments was highest in the warm populations irrespective of temperature, indicating cogradient variation. The optimal temperatures for growth and reproduction were similar irrespective of origin, but cold-origin snails always had the lowest performance, and seasonal-origin snails often performed at an intermediate level compared to snails originating in either stable environment. Our results indicate that central life-history traits can differ in their mode of evolution, with survival following the predictions of thermal optimality models, whereas ecological constraints have shaped the evolution of growth rates in local populations. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  13. Reflection seismic imaging in the volcanic area of the geothermal field Wayang Windu, Indonesia

    NASA Astrophysics Data System (ADS)

    Polom, Ulrich; Wiyono, Wiyono; Pramono, Bambang; Krawczyk, CharLotte M.

    2014-05-01

    Reflection seismic exploration in volcanic areas is still a scientific challenge and requires major efforts to develop imaging workflows capable of an economic utilization, e.g., for geothermal exploration. The SESaR (Seismic Exploration and Safety Risk study for decentral geothermal plants in Indonesia) project therefore tackles still not well resolved issues concerning wave propagation or energy absorption in areas covered by pyroclastic sediments using both active P-wave and S-wave seismics. Site-specific exploration procedures were tested in different tectonic and lithological regimes to compare imaging conditions. Based on the results of a small-scale, active seismic pre-site survey in the area of the Wayang Windu geothermal field in November 2012, an additional medium-scale active seismic experiment using P-waves was carried out in August 2013. The latter experiment was designed to investigate local changes of seismic subsurface response, to expand the knowledge about capabilities of the vibroseis method for seismic surveying in regions covered by pyroclastic material, and to achieve higher depth penetration. Thus, for the first time in the Wayang Windu geothermal area, a powerful, hydraulically driven seismic mini-vibrator device of 27 kN peak force (LIAG's mini-vibrator MHV2.7) was used as seismic source instead of the weaker hammer blow applied in former field surveys. Aiming at acquiring parameter test and production data southeast of the Wayang Windu geothermal power plant, a 48-channel GEODE recording instrument of the Badan Geologi was used in a high-resolution configuration, with receiver group intervals of 5 m and source intervals of 10 m. Thereby, the LIAG field crew, Star Energy, GFZ Potsdam, and ITB Bandung acquired a nearly 600 m long profile. In general, we observe the successful applicability of the vibroseis method for such a difficult seismic acquisition environment. Taking into account the local conditions at Wayang Windu, the method is

  14. Structural Data for the Columbus Salt Marsh Geothermal Area - GIS Data

    DOE Data Explorer

    Faulds, James E.

    2011-12-31

    Shapefiles and spreadsheets of structural data, including attitudes of faults and strata and slip orientations of faults. - Detailed geologic mapping of ~30 km2 was completed in the vicinity of the Columbus Marsh geothermal field to obtain critical structural data that would elucidate the structural controls of this field. - Documenting E‐ to ENE‐striking left lateral faults and N‐ to NNE‐striking normal faults. - Some faults cut Quaternary basalts. - This field appears to occupy a displacement transfer zone near the eastern end of a system of left‐lateral faults. ENE‐striking sinistral faults diffuse into a system of N‐ to NNE‐striking normal faults within the displacement transfer zone. - Columbus Marsh therefore corresponds to an area of enhanced extension and contains a nexus of fault intersections, both conducive for geothermal activity.

  15. New Zealand geothermal: Wairakei -- 40 years

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    This quarterly bulletin highlights the geothermal developments in New Zealand with the following articles: A brief history of the Wairakei geothermal power project; Geothermal resources in New Zealand -- An overview; Domestic and commercial heating and bathing -- Rotorua area; Kawerau geothermal development: A case study; Timber drying at Kawerau; Geothermal greenhouses at Kawerau; Drying of fibrous crops using geothermal steam and hot water at the Taupo Lucerne Company; Prawn Park -- Taupo, New Zealand; Geothermal orchids; Miranda hot springs; and Geothermal pipeline.

  16. Genetic divergence and isolation by thermal environment in geothermal populations of an aquatic invertebrate.

    PubMed

    Johansson, M P; Quintela, M; Laurila, A

    2016-09-01

    Temperature is one of the most influential forces of natural selection impacting all biological levels. In the face of increasing global temperatures, studies over small geographic scales allowing investigations on the effects of gene flow are of great value for understanding thermal adaptation. Here, we investigated genetic population structure in the freshwater gastropod Radix balthica originating from contrasting thermal habitats in three areas of geothermal activity in Iceland. Snails from 32 sites were genotyped at 208 AFLP loci. Five AFLPs were identified as putatively under divergent selection in Lake Mývatn, a geothermal lake with an almost 20 °C difference in mean temperature across a distance of a few kilometres. In four of these loci, variation across all study populations was correlated with temperature. We found significant population structure in neutral markers both within and between the areas. Cluster analysis using neutral markers classified the sites mainly by geography, whereas analyses using markers under selection differentiated the sites based on temperature. Isolation by distance was stronger in the neutral than in the outlier loci. Pairwise differences based on outlier FST were significantly correlated with temperature at different spatial scales, even after correcting for geographic distance or neutral pairwise FST differences. In general, genetic variation decreased with increasing environmental temperature, possibly suggesting that natural selection had reduced the genetic diversity in the warm origin sites. Our results emphasize the influence of environmental temperature on the genetic structure of populations and suggest local thermal adaptation in these geothermal habitats. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  17. Geothermal Gradients in Oregon, 1985-1994

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Blackwell, D.D.

    1995-01-01

    This data set is comprised of three groups of temperature-depth data. All the sites are located in southeastern Oregon. The first is a set of 7 wells logged during 1993 in south central Oregon in the Basin and Range province. All these wells, with the exception of the Blue Mountain Oil well, are water wells. These wells were part of a geothermal reconnaissance of this area. The Blue Mountain oil well of this set has been described by Sass et al. (1971) as well. Gannet in the vicinity of the Vale, Oregon (Bowen and Blackwell, 1972; Blackwell et al., 1978)more » geothermal system in Malheur County. These wells were logged in 1986 during a study of the area described by Gannett (1988). There are 17 wells (plus one relog) in this data set. All these wells are in a small area just east of the town of Vale in Malheur County. The second set of data consists of a group of wells that were logged by Marshall The third set of data represents the results of an exploration project in the general area of the Lake Owyhee thermal area in Malheur County. This data set is comprised of 16 wells. This data set was collected by Hunt Energy Corporation and made available though the efforts of Roger Bowers. A small scale map of the locations of the wells is shown in Figure 1. The well location and some pertinent information about the wells is shown in Table 1. The detailed lists of temperature-depth data and plots for each well, either individually or with a group, follow the list of references cited.« less

  18. 3-Dimensional Geologic Modeling Applied to the Structural Characterization of Geothermal Systems: Astor Pass, Nevada, USA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Siler, Drew L; Faulds, James E; Mayhew, Brett

    2013-04-16

    Geothermal systems in the Great Basin, USA, are controlled by a variety of fault intersection and fault interaction areas. Understanding the specific geometry of the structures most conducive to broad-scale geothermal circulation is crucial to both the mitigation of the costs of geothermal exploration (especially drilling) and to the identification of geothermal systems that have no surface expression (blind systems). 3-dimensional geologic modeling is a tool that can elucidate the specific stratigraphic intervals and structural geometries that host geothermal reservoirs. Astor Pass, NV USA lies just beyond the northern extent of the dextral Pyramid Lake fault zone near the boundarymore » between two distinct structural domains, the Walker Lane and the Basin and Range, and exhibits characteristics of each setting. Both northwest-striking, left-stepping dextral faults of the Walker Lane and kinematically linked northerly striking normal faults associated with the Basin and Range are present. Previous studies at Astor Pass identified a blind geothermal system controlled by the intersection of west-northwest and north-northwest striking dextral-normal faults. Wells drilled into the southwestern quadrant of the fault intersection yielded 94°C fluids, with geothermometers suggesting a maximum reservoir temperature of 130°C. A 3-dimensional model was constructed based on detailed geologic maps and cross-sections, 2-dimensional seismic data, and petrologic analysis of the cuttings from three wells in order to further constrain the structural setting. The model reveals the specific geometry of the fault interaction area at a level of detail beyond what geologic maps and cross-sections can provide.« less

  19. Geothermal development plan: Yuma County

    NASA Astrophysics Data System (ADS)

    White, D. H.; Goldstone, L. A.

    1982-08-01

    The potential for utilizing geothermal energy was evaluated. Four potential geothermal resource areas with temperatures less than 900C (1940F) were identified, and in addition, two areas are inferred to contain geothermal resources with intermediate temperature potential. The resource areas are isolated. One resource site contains a hot dry rock resource. Anticipated population growth in the county is expected to be 2% per year over the next 40 years. The primary employment sector is agriculture, though some light industry is located in the county. Water supplies are found to be adequate to support future growth without adverse affect on agriculture. In addition, several agricultural processors were found, concentrated in citrus processing and livestock raising. It is suggested that by the year 2000, geothermal energy may economically provide the energy equivalent of 53,000 barrels of oil per year to the industrial sector if developed privately. Geothermal utilization projections increase to 132,000 barrels of oil per year by 2000 if a municipal utility developed the resource.

  20. Classification of public lands valuable for geothermal steam and associated geothermal resources

    USGS Publications Warehouse

    Godwin, Larry H.; Haigler, L.B.; Rioux, R.L.; White, D.E.; Muffler, L.J.; Wayland, R.G.

    1971-01-01

    The Organic Act of 1879 (43 U.S.C. 31) that established the U.S. Geological Survey provided, among other things, for the classification of the public lands and for the examination of the geological structure, mineral sources, and products of the national domain. In order to provide uniform executive action in classifying public lands, standards for determining which lands are valuable for mineral resources, for example, leasable mineral lands, or for other products are prepared by the U.S. Geological Survey. This report presents the classification standards for determining which Federal lands are classifiable as geothermal steam and associated geothermal resources lands under the Geothermal Steam Act of 1970 (84 Star. 1566). The concept of a geothermal resources province is established for classification of lands for the purpose of retention in Federal ownership of rights to geothermal resources upon disposal of Federal lands. A geothermal resources province is defined as an area in which higher than normal temperatures are likely to occur with depth and in which there is a reasonable possibility of finding reservoir rocks that will yield steam or heated fluids to wells. The determination of a 'known geothermal resources area' is made after careful evaluation of the available geologic, geochemical, and geophysical data and any evidence derived from nearby discoveries, competitive interests, and other indicia. The initial classification required by the Geothermal Steam Act of 1970 is presented.

  1. Classification of public lands valuable for geothermal steam and associated geothermal resources

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goodwin, L.H.; Haigler, L.B.; Rioux, R.L.

    1973-01-01

    The Organic Act of 1879 (43 USC 31) that established the US Geological Survey provided, among other things, for the classification of the public lands and for the examination of the geological structure, mineral resources, and products of the national domain. In order to provide uniform executive action in classifying public lands, standards for determining which lands are valuable for mineral resources, for example, leasable mineral lands, or for other products are prepared by the US Geological Survey. This report presents the classification standards for determining which Federal lands are classifiable as geothermal steam and associated geothermal resources lands undermore » the Geothermal Steam Act of 1970 (84 Stat. 1566). The concept of a geothermal resouces province is established for classification of lands for the purpose of retention in Federal ownership of rights to geothermal resources upon disposal of Federal lands. A geothermal resources province is defined as an area in which higher than normal temperatures are likely to occur with depth and in which there is a resonable possiblity of finding reservoir rocks that will yield steam or heated fluids to wells. The determination of a known geothermal resources area is made after careful evaluation of the available geologic, geochemical, and geophysical data and any evidence derived from nearby discoveries, competitive interests, and other indicia. The initial classification required by the Geothermal Steam Act of 1970 is presented.« less

  2. Mixing effects on geothermometric calculations of the Newdale geothermal area in the Eastern Snake River Plain, Idaho

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ghanashayam Neupane; Earl D. Mattson; Travis L. McLing

    The Newdale geothermal area in Madison and Fremont Counties in Idaho is a known geothermal resource area whose thermal anomaly is expressed by high thermal gradients and numerous wells producing warm water (up to 51 °C). Geologically, the Newdale geothermal area is located within the Eastern Snake River Plain (ESRP) that has a time-transgressive history of sustained volcanic activities associated with the passage of Yellowstone Hotspot from the southwestern part of Idaho to its current position underneath Yellowstone National Park in Wyoming. Locally, the Newdale geothermal area is located within an area that was subjected to several overlapping and nestedmore » caldera complexes. The Tertiary caldera forming volcanic activities and associated rocks have been buried underneath Quaternary flood basalts and felsic volcanic rocks. Two southeast dipping young faults (Teton dam fault and an unnamed fault) in the area provide the structural control for this localized thermal anomaly zone. Geochemically, water samples from numerous wells in the area can be divided into two broad groups – Na-HCO3 and Ca-(Mg)-HCO3 type waters and are considered to be the product of water-rhyolite and water-basalt interactions, respectively. Each type of water can further be subdivided into two groups depending on their degree of mixing with other water types or interaction with other rocks. For example, some bivariate plots indicate that some Ca-(Mg)-HCO3 water samples have interacted only with basalts whereas some samples of this water type also show limited interaction with rhyolite or mixing with Na-HCO3 type water. Traditional geothermometers [e.g., silica variants, Na-K-Ca (Mg-corrected)] indicate lower temperatures for this area; however, a traditional silica-enthalpy mixing model results in higher reservoir temperatures. We applied a new multicomponent equilibrium geothermometry tool (e.g., Reservoir Temperature Estimator, RTEst) that is based on inverse geochemical modeling

  3. Bathymetric map and area/capacity table for Castle Lake, Washington

    USGS Publications Warehouse

    Mosbrucker, Adam R.; Spicer, Kurt R.

    2017-11-14

    The May 18, 1980, eruption of Mount St. Helens produced a 2.5-cubic-kilometer debris avalanche that dammed South Fork Castle Creek, causing Castle Lake to form behind a 20-meter-tall blockage. Risk of a catastrophic breach of the newly impounded lake led to outlet channel stabilization work, aggressive monitoring programs, mapping efforts, and blockage stability studies. Despite relatively large uncertainty, early mapping efforts adequately supported several lake breakout models, but have limited applicability to current lake monitoring and hazard assessment. Here, we present the results of a bathymetric survey conducted in August 2012 with the purpose of (1) verifying previous volume estimates, (2) computing an area/capacity table, and (3) producing a bathymetric map. Our survey found seasonal lake volume ranges between 21.0 and 22.6 million cubic meters with a fundamental vertical accuracy representing 0.88 million cubic meters. Lake surface area ranges between 1.13 and 1.16 square kilometers. Relationships developed by our results allow the computation of lake volume from near real-time lake elevation measurements or from remotely sensed imagery.

  4. Geothermal Target Areas in Colorado as Identified by Remote Sensing Techniques

    DOE Data Explorer

    Khalid Hussein

    2012-02-01

    This layer contains the areas identified as targets of potential geothermal activity. The Criteria used to identify the target areas include: hot/warm surface exposures modeled from ASTER/Landsat satellite imagery and geological characteristics, alteration mineral commonly associated with hot springs (clays, Si, and FeOx) modeled from ASTER and Landsat data, Colorado Geological Survey (CGS) known thermal hot springs/wells and heat-flow data points, Colorado deep-seated fault zones, weakened basement identified from isostatic gravity data, and Colorado sedimentary and topographic characteristics.

  5. Geothermal Geodatabase for Rico Hot Springs Area and Lemon Hot Springs, Dolores and San Miguel Counties, Colorado

    DOE Data Explorer

    Richard Zehner

    2012-11-01

    This geodatabase was built to cover several geothermal targets developed by Flint Geothermal in 2012 during a search for high-temperature systems that could be exploited for electric power development. Several of the thermal springs have geochemistry and geothermometry values indicative of high-temperature systems. In addition, the explorationists discovered a very young Climax-style molybdenum porphyry system northeast of Rico, and drilling intersected thermal waters at depth. Datasets include: 1. Structural data collected by Flint Geothermal 2. Point information 3. Mines and prospects from the USGS MRDS dataset 4. Results of reconnaissance shallow (2 meter) temperature surveys 5. Air photo lineaments 6. Areas covered by travertine 7. Groundwater geochemistry 8. Land ownership in the Rico area 9. Georeferenced geologic map of the Rico Quadrangle, by Pratt et al. 10. Various 1:24,000 scale topographic maps

  6. Investigation of the heat source(s) of the Surprise Valley Geothermal System, Northern California

    NASA Astrophysics Data System (ADS)

    Tanner, N.; Holt, C. D.; Hawkes, S.; McClain, J. S.; Safford, L.; Mink, L. L.; Rose, C.; Zierenberg, R. A.

    2016-12-01

    Concerns about environmental impacts and energy security have led to an increased interest in sustainable and renewable energy resources, including geothermal systems. It is essential to know the permeability structure and possible heat source(s) of a geothermal area in order to assess the capacity and extent of the potential resource. We have undertaken geophysical surveys at the Surprise Valley Hot Springs in Cedarville, California to characterize essential parameters related to a fault-controlled geothermal system. At present, the heat source(s) for the system are unknown. Igneous bodies in the area are likely too old to have retained enough heat to supply the system, so it is probable that fracture networks provide heat from some deeper or more distributed heat sources. However, the fracture system and permeability structure remain enigmatic. The goal of our research is to identify the pathways for fluid transport within the Surprise Valley geothermal system using a combination of geophysical methods including active seismic surveys and short- and long-period magnetotelluric (MT) surveys. We have collected 14 spreads, consisting of 24 geophones each, of active-source seismic data. We used a "Betsy Gun" source at 8 to 12 locations along each spread and have collected and analyzed about 2800 shot-receiver pairs. Seismic velocities reveal shallow lake sediments, as well as velocities consistent with porous basalts. The latter, with velocities of greater than 3.0 km/s, lie along strike with known hot springs and faulted and tilted basalt outcrops outside our field area. This suggests that basalts may provide a permeable pathway through impermeable lake deposits. We conducted short-period (10Hz-60kHz) MT measurements at 33 stations. Our short-period MT models indicate shallow resistive blocks (>100Ωm) with a thin cover of more conductive sediments ( 10Ωm) at the surface. Hot springs are located in gaps between resistive blocks and are connected to deeper low

  7. 78 FR 63868 - Amendment of Restricted Area R-2515; Muroc Lake, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-25

    ...-0802; Airspace Docket No. 13-AWP-7] RIN 2120-AA66 Amendment of Restricted Area R-2515; Muroc Lake, CA... using agency name for Restricted Area R-2515 Muroc Lake, CA, to read ``Commander, 412th Test Wing (412... using agency name for Restricted Area R-2515 Muroc Lake, CA, from ``Commander Air Force Flight Test...

  8. View of the Salt Lake City, Utah area

    NASA Image and Video Library

    1973-08-30

    SL3-22-0322 (July-September 1973) --- An oblique view of the Salt Lake City, Utah area as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. Approximately two-thirds of the Great Salt Lake is in view. The smaller body of water south of Salt Lake City is Utah Lake. The Wasatch Range is on the east side of the Great Salt Lake. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

  9. A Geothermal GIS for Nevada: Defining Regional Controls and Favorable Exploration Terrains for Extensional Geothermal Systems

    USGS Publications Warehouse

    Coolbaugh, M.F.; Taranik, J.V.; Raines, G.L.; Shevenell, L.A.; Sawatzky, D.L.; Bedell, R.; Minor, T.B.

    2002-01-01

    Spatial analysis with a GIS was used to evaluate geothermal systems in Nevada using digital maps of geology, heat flow, young faults, young volcanism, depth to groundwater, groundwater geochemistry, earthquakes, and gravity. High-temperature (>160??C) extensional geothermal systems are preferentially associated with northeast-striking late Pleistocene and younger faults, caused by crustal extension, which in most of Nevada is currently oriented northwesterly (as measured by GPS). The distribution of sparse young (160??C) geothermal systems in Nevada are more likely to occur in areas where the groundwater table is shallow (<30m). Undiscovered geothermal systems may occur where groundwater levels are deeper and hot springs do not issue at the surface. A logistic regression exploration model was developed for geothermal systems, using young faults, young volcanics, positive gravity anomalies, and earthquakes to predict areas where deeper groundwater tables are most likely to conceal geothermal systems.

  10. Geothermal mineralized scales in the pipe system of the geothermal Piancastagnaio power plant (Mt. Amiata geothermal area): a key to understand the stibnite, cinnabarite and gold mineralization of Tuscany (central Italy)

    NASA Astrophysics Data System (ADS)

    Morteani, Giulio; Ruggieri, Giovanni; Möller, Peter; Preinfalk, Christine

    2011-02-01

    The CO2-rich geothermal fluids produced in the Piancastagnaio geothermal field (Mt. Amiata geothermal area, Southern Tuscany, Italy) show temperatures up to 360°C and pressures of about 200 bar at depths of around 3,500 m (Giolito, Ph.D. thesis, Università degli Studi di Firenze, Italy, pp 1-147, 2005). CaCO3- and/or SiO2-dominated scales are deposited in the pipes leading to the pressure and atmospheric separators of the geothermal wells. High content of metastibnite and/or stibnite in both calcite and silica scales and Sb contents of up to 50 mg/L in the fluids indicate their mineralising potential. The red or black colours of the scales depend on the predominance of red metastibnite or black stibnite, respectively. In our condensation experiments, as well as during deposition of the scales, metastibnite is the first Sb2S3 mineral to form. In a second stage, metastibnite is transformed to stibnite. During depressurization the Hg content of geothermal fluids partitions preferentially into the gas phase, whereas Sb and As remain in the liquid phase. This separation explains the often observed areal separation of Hg and Sb mineralization. The multistage deposition of Sb in the mining district of Tuscany is due to a periodic restoration of the permeability of the ore-bearing faults by microseismic events and subsequent host rock brecciation. The still ongoing microseismic events are induced by the accumulation of high-pressure CO2-rich fluids along faults followed by mechanical failure of the faults.

  11. Roger Lake research natural area: guidebook supplement 29.

    Treesearch

    J. Dana Visalli

    2006-01-01

    Roger Lake Research Natural Area (RNA), a 174.7-ha reserve in north-central Washington, contains a rich diversity of landforms, plant communities, and wildlife habitats. Spreading outward from the lake itself, sedge and sphagnum fens give way to upland coniferous forest, granitic cliffs, and a relictual, high-altitude big sagebrush-whitebark pine (Artemisia tridentata-...

  12. Geothermal Exploration Case Studies on OpenEI (Presentation)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Young, K.; Bennett, M.; Atkins, D.

    2014-03-01

    The U.S. Geological Survey (USGS) resource assessment (Williams et al., 2008) outlined a mean 30 GWe of undiscovered hydrothermal resource in the western United States. One goal of the U.S. Department of Energy's (DOE) Geothermal Technology Office (GTO) is to accelerate the development of this undiscovered resource. DOE has focused efforts on helping industry identify hidden geothermal resources to increase geothermal capacity in the near term. Increased exploration activity will produce more prospects, more discoveries, and more readily developable resources. Detailed exploration case studies akin to those found in oil and gas (e.g. Beaumont and Foster, 1990-1992) will give developersmore » central location for information gives models for identifying new geothermal areas, and guide efficient exploration and development of these areas. To support this effort, the National Renewable Energy Laboratory (NREL) has been working with GTO to develop a template for geothermal case studies on the Geothermal Gateway on OpenEI. In 2012, the template was developed and tested with two case studies: Raft River Geothermal Area (http://en.openei.org/wiki/Raft_River_Geothermal_Area) and Coso Geothermal Area (http://en.openei.org/wiki/Coso_Geothermal_Area). In 2013, ten additional case studies were completed, and Semantic MediaWiki features were developed to allow for more data and the direct citations of these data. These case studies are now in the process of external peer review. In 2014, NREL is working with universities and industry partners to populate additional case studies on OpenEI. The goal is to provide a large enough data set to start conducting analyses of exploration programs to identify correlations between successful exploration plans for areas with similar geologic occurrence models.« less

  13. Incidence of cancer among residents of high temperature geothermal areas in Iceland: a census based study 1981 to 2010

    PubMed Central

    2012-01-01

    Background Residents of geothermal areas are exposed to geothermal emissions and water containing hydrogen sulphide and radon. We aim to study the association of the residence in high temperature geothermal area with the risk of cancer. Methods This is an observational cohort study where the population of a high-temperature geothermal area (35,707 person years) was compared with the population of a cold, non-geothermal area (571,509 person years). The cohort originates from the 1981 National Census. The follow up from 1981 to 2010 was based on record linkage by personal identifier with nation-wide death and cancer registries. Through the registries it was possible to ascertain emigration and vital status and to identify the cancer cases, 95% of which had histological verification. The hazard ratio (HR) and 95% confidence intervals (CI) were estimated in Cox-model, adjusted for age, gender, education and housing. Results Adjusted HR in the high-temperature geothermal area for all cancers was 1.22 (95% CI 1.05 to 1.42) as compared with the cold area. The HR for pancreatic cancer was 2.85 (95% CI 1.39 to 5.86), breast cancer 1.59 (95% CI 1.10 to 2.31), lymphoid and hematopoietic cancer 1.64 (95% CI 1.00 to 2.66), and non-Hodgkins lymphoma 3.25 (95% CI 1.73 to 6.07). The HR for basal cell carcinoma of the skin was 1.61 (95% CI 1.10 to 2.35). The HRs were increased for cancers of the nasal cavities, larynx, lung, prostate, thyroid gland and for soft tissue sarcoma; however the 95% CIs included unity. Conclusions More precise information on chemical and physical exposures are needed to draw firm conclusions from the findings. The significant excess risk of breast cancer, and basal cell carcinoma of the skin, and the suggested excess risk of other radiation-sensitive cancers, calls for measurement of the content of the gas emissions and the hot water, which have been of concern in previous studies in volcanic areas. There are indications of an exposure

  14. High mountain lake Research Natural Areas in Idaho

    Treesearch

    Fred W. Rabe

    2001-01-01

    High mountain lakes in Idaho total about 1800 and represent one of the most pristine type ecosystems in the country. Limnological characteristics are described for 27 lakes and 20 ponds in 32 established and proposed Research Natural Areas (RNA) representing seven subregions in the state. Field collections were made from the 1960s through 1999 by different researchers...

  15. Modeling Seasonal Thermal Radiance Cycles for Change Detection at Volcanic / Geothermal Areas

    NASA Astrophysics Data System (ADS)

    Vaughan, R.; Beuttel, B. S.

    2013-12-01

    Remote sensing observations of thermal features associated with (and often preceding) volcanic activity have been used for decades to detect and monitor volcanism. However, anomalous thermal precursors to volcanic eruptions are usually only recognized retrospectively. One of the reasons for this is that precursor thermal activity is often too subtle in magnitude (spatially, temporally, or in absolute temperature) to be unambiguously detected in time to issue warnings or forecasts. Part of the reason for this is the trade-off between high spatial and high temporal resolution associated with satellite imaging systems. Thus, the goal of this work has been to develop some techniques for using high-temporal-resolution, coarse-spatial-resolution imagery to try to detect subtle thermal anomalies. To identify anomalies, background thermal activity must first be characterized. Every active, or potentially active, volcano has a unique thermal history that provides information about normal background thermal activity due to seasonal or diurnal variations. Understanding these normal variations allows recognition of anomalous activity that may be due to volcanic / hydrothermal processes - ultimately with a lead time that may be sufficient to issue eruption warnings or forecasts. Archived MODIS data, acquired ~daily from 2000 to 2012, were used to investigate seasonal thermal cycles at three volcanic areas with different types of thermal features: Mount St. Helens, which had a dacite dome-building eruption from 2004-2008; Mount Ruapehu, which has a 500-m diameter active summit crater lake; and Yellowstone, which is a large active geothermal system that has hundreds of hot springs and fumarole fields spread out over a very large area. The focus has been on using MODIS 1-km sensor radiance data in the MIR and TIR wavelength regions that are sensitive to thermal emission from features that range in temperature from hundreds of °C, down to tens of °C (below the boiling temperature

  16. Detection of Geothermal Phosphite Using High Performance Liquid Chromatography

    PubMed Central

    Pech, Herbe; Henry, Amanda; Khachikian, Crist S.; Salmassi, Tina M.; Hanrahan, Grady; Foster, Krishna L.

    2009-01-01

    Little is known about the pre-biotic mechanisms that initiated the bioavailability of phosphorus, an element essential to life. A better understanding of phosphorus speciation in modern earth environments representative of early earth, may help to elucidate the origins of bioavailable phosphorus. This paper presents the first quantitative measurements of phosphite in a pristine geothermal pool representative of early earth. Phosphite and phosphate were initially identified and quantified in geothermal pool and stream samples at Hot Creek Gorge near Mammoth Lakes, California using suppressed conductivity ion chromatography. Results confirmed the presence of 0.06 ± 0.02 μM of phosphite and 0.05 ± 0.01 μM of phosphate in a geothermal pool. In the stream, phosphite concentrations were below detection limit (0.04 μM) and phosphate was measured at 1.06 ± 0.36 μM. The presence of phosphite in the geothermal pool was confirmed using both chemical oxidation and ion chromatography/mass spectrometry. PMID:19921877

  17. Geothermal energy abstract sets. Special report No. 14

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stone, C.

    1985-01-01

    This bibliography contains annotated citations in the following areas: (1) case histories; (2) drilling; (3) reservoir engineering; (4) injection; (5) geothermal well logging; (6) environmental considerations in geothermal development; (7) geothermal well production; (8) geothermal materials; (9) electric power production; (10) direct utilization of geothermal energy; (11) economics of geothermal energy; and (12) legal, regulatory and institutional aspects. (ACR)

  18. 33 CFR 165.1171 - Copper Canyon, Lake Havasu, Colorado River-Regulated Navigation Area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Copper Canyon, Lake Havasu... Guard District § 165.1171 Copper Canyon, Lake Havasu, Colorado River—Regulated Navigation Area. (a) Location. The following is a regulated navigation area: (1) In the water area of Copper Canyon, Lake Havasu...

  19. 33 CFR 165.1171 - Copper Canyon, Lake Havasu, Colorado River-Regulated Navigation Area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Copper Canyon, Lake Havasu... Guard District § 165.1171 Copper Canyon, Lake Havasu, Colorado River—Regulated Navigation Area. (a) Location. The following is a regulated navigation area: (1) In the water area of Copper Canyon, Lake Havasu...

  20. Geo Techno Park potential at Arjuno-Welirang Volcano hosted geothermal area, Batu, East Java, Indonesia (Multi geophysical approach)

    NASA Astrophysics Data System (ADS)

    Maryanto, Sukir

    2017-11-01

    Arjuno Welirang Volcano Geothermal (AWVG) is located around Arjuno-Welirang Volcano in Malang, East Java, about 100 km southwest of Surabaya, the capital city of East Java province, and is still an undeveloped area of the geothermal field. The occurrence of solfatara and fumaroles with magmatic gasses indicated the existence of a volcanic geothermal system in the subsurface. A few hot springs are found in the Arjuno-Welirang volcanic complex, such as Padusan hot spring, Songgoriti hot spring, Kasinan hot spring, and Cangar hot spring. Multi geophysical observations in AWVG complex was carried out in order to explore the subsurface structure in supporting the plan of Geo Techno Park at the location. Gravity, Magnetic, Microearthquake, and Electrical Resistivity Tomography (ERT) methods were used to investigate the major and minor active faulting zones whether hot springs circulation occurs in these zones. The gravity methods allowed us to locate the subsurface structure and to evaluate their geometrical relationship base on density anomaly. Magnetic methods allow us to discriminate conductive areas which could correspond to an increase in thermal fluid circulation in the investigated sites. Micro-earthquakes using particle motion analysis to locate the focal depth related with hydrothermal activity and electrical resistivity tomography survey offers methods to locate more detail subsurface structure and geothermal fluids near the surface by identifying areas affected by the geothermal fluid. The magnetic and gravity anomaly indicates the subsurface structure of AWVG is composed of basalt rock, sulfide minerals, sandstone, and volcanic rock with high minor active fault structure as a medium for fluid circulation. While using micro-earthquake data in AWVG shown shallow focal depth range approximate 60 meters which indicates shallow hydrothermal circulation in AWVG. The geothermal fluid circulation zones along the fault structure resulted in some hot springs in a

  1. 33 CFR 334.520 - Lake George, Fla.; naval bombing area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Lake George, Fla.; naval bombing....; naval bombing area. (a) The danger zone. An area in the eastern part of Lake George described as follows.... (2) Prior to each bombing operation the danger zone will be patrolled by naval aircraft which will...

  2. 33 CFR 334.520 - Lake George, Fla.; naval bombing area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Lake George, Fla.; naval bombing....; naval bombing area. (a) The danger zone. An area in the eastern part of Lake George described as follows.... (2) Prior to each bombing operation the danger zone will be patrolled by naval aircraft which will...

  3. Geo-electrical and geological strikes of the Mount Lamongan geothermal area, East Java, Indonesia – preliminary results

    NASA Astrophysics Data System (ADS)

    Nugraheni, L. R.; Niasari, S. W.; Nukman, M.

    2018-04-01

    Geothermal manifestations located in the Tiris, Mount Lamongan, Probolinggo, consist of warm springs. These warm springs have temperature from 35° until 45°C. Tiris fault has NW-SE dominant orientation, similar to some lineaments of maars and cinder cones around Mount Lamongan. The Mount Lamongan geothermal area is situated between Bromo and Argapura volcanoes. This study aims to map the geo-electrical and geological strikes in the study area. Phase tensor analysis has been performed in this study to determine geo-electrical strike of study area. Geological field campaign has been conducted to measure geological strikes. Then, orientation of geo-electrical strike was compared to geological strike. The result presents that the regional geological strike of study area is NW-SE while the orientation of geo-electrical strike is N-S.

  4. ALPINE LAKES WILDERNESS STUDY AREA, WASHINGTON.

    USGS Publications Warehouse

    Gualtieri, J.L.; Thurber, H.K.

    1984-01-01

    The Alpine Lakes Wilderness study area, located in the central part of the Cascade Mountains of Washington was examined for its mineral-resource potential. On the basis of that study the area was found to contain deposits of copper, other base metals, and gold and silver. Probable or substantiated mineral-resource potential exists for these commodities in the southwest-central, northwest, and southeast-central parts of the area. The geologic terrane precludes the occurrence of fossil fuel resources.

  5. Geothermal resources of California sedimentary basins

    USGS Publications Warehouse

    Williams, C.F.; Grubb, F.V.; Galanis, S.P.

    2004-01-01

    The 2004 Department of Energy (DOE) Strategic Plan for geothermal energy calls for expanding the geothermal resource base of the United States to 40,000 MW of electric power generating potential. This will require advances in technologies for exploiting unconventional geothermal resources, including Enhanced Geothermal Systems (EGS) and geopressured geothermal. An investigation of thermal conditions in California sedimentary basins through new temperature and heat flow measurements reveals significant geothermal potential in some areas. In many of the basins, the combined cooling effects of recent tectonic and sedimentary processes result in relatively low (<60 mW/m2) heat flow and geothermal gradients. For example, temperatures in the upper 3 km of San Joaquin, Sacramento and Ventura basins are typically less than 125??C and do not reach 200??c by 5 km. By contrast, in the Cuyama, Santa Maria and western Los Angeles basins, heat flow exceeds 80 mW/m2 and temperatures near or above 200??C occur at 4 to 5 km depth, which represents thermal conditions equivalent to or hotter than those encountered at the Soultz EGS geothermal site in Europe. Although the extractable geothermal energy contained in these basins is not large relative to the major California producing geothermal fields at The Geysers or Salton Sea, the collocation in the Los Angeles basin of a substantial petroleum extraction infrastructure and a major metropolitan area may make it attractive for eventual geothermal development as EGS technology matures.

  6. Temperature Effects on Biomass and Regeneration of Vegetation in a Geothermal Area

    PubMed Central

    Nishar, Abdul; Bader, Martin K.-F.; O’Gorman, Eoin J.; Deng, Jieyu; Breen, Barbara; Leuzinger, Sebastian

    2017-01-01

    Understanding the effects of increasing temperature is central in explaining the effects of climate change on vegetation. Here, we investigate how warming affects vegetation regeneration and root biomass and if there is an interactive effect of warming with other environmental variables. We also examine if geothermal warming effects on vegetation regeneration and root biomass can be used in climate change experiments. Monitoring plots were arranged in a grid across the study area to cover a range of soil temperatures. The plots were cleared of vegetation and root-free ingrowth cores were installed to assess above and below-ground regeneration rates. Temperature sensors were buried in the plots for continued soil temperature monitoring. Soil moisture, pH, and soil chemistry of the plots were also recorded. Data were analyzed using least absolute shrinkage and selection operator and linear regression to identify the environmental variable with the greatest influence on vegetation regeneration and root biomass. There was lower root biomass and slower vegetation regeneration in high temperature plots. Soil temperature was positively correlated with soil moisture and negatively correlated with soil pH. Iron and sulfate were present in the soil in the highest quantities compared to other measured soil chemicals and had a strong positive relationship with soil temperature. Our findings suggest that soil temperature had a major impact on root biomass and vegetation regeneration. In geothermal fields, vegetation establishment and growth can be restricted by low soil moisture, low soil pH, and an imbalance in soil chemistry. The correlation between soil moisture, pH, chemistry, and plant regeneration was chiefly driven by soil temperature. Soil temperature was negatively correlated to the distance from the geothermal features. Apart from characterizing plant regeneration on geothermal soils, this study further demonstrates a novel approach to global warming experiments

  7. Temperature Effects on Biomass and Regeneration of Vegetation in a Geothermal Area.

    PubMed

    Nishar, Abdul; Bader, Martin K-F; O'Gorman, Eoin J; Deng, Jieyu; Breen, Barbara; Leuzinger, Sebastian

    2017-01-01

    Understanding the effects of increasing temperature is central in explaining the effects of climate change on vegetation. Here, we investigate how warming affects vegetation regeneration and root biomass and if there is an interactive effect of warming with other environmental variables. We also examine if geothermal warming effects on vegetation regeneration and root biomass can be used in climate change experiments. Monitoring plots were arranged in a grid across the study area to cover a range of soil temperatures. The plots were cleared of vegetation and root-free ingrowth cores were installed to assess above and below-ground regeneration rates. Temperature sensors were buried in the plots for continued soil temperature monitoring. Soil moisture, pH, and soil chemistry of the plots were also recorded. Data were analyzed using least absolute shrinkage and selection operator and linear regression to identify the environmental variable with the greatest influence on vegetation regeneration and root biomass. There was lower root biomass and slower vegetation regeneration in high temperature plots. Soil temperature was positively correlated with soil moisture and negatively correlated with soil pH. Iron and sulfate were present in the soil in the highest quantities compared to other measured soil chemicals and had a strong positive relationship with soil temperature. Our findings suggest that soil temperature had a major impact on root biomass and vegetation regeneration. In geothermal fields, vegetation establishment and growth can be restricted by low soil moisture, low soil pH, and an imbalance in soil chemistry. The correlation between soil moisture, pH, chemistry, and plant regeneration was chiefly driven by soil temperature. Soil temperature was negatively correlated to the distance from the geothermal features. Apart from characterizing plant regeneration on geothermal soils, this study further demonstrates a novel approach to global warming experiments

  8. Derivation of Lake Areas and Elevations for the Mackenzie Basin Using Satellite Remote Sensing

    NASA Technical Reports Server (NTRS)

    Birkett, Charon; Kite, Geoff

    1997-01-01

    Modelling hydrological processes in large watersheds flowing to the Arctic ocean is one step towards larger-scale modelling of the global water and energy cycles. Models of the Mackenzie River Basin (Northern Canada) are currently available but omit explicit routing of river flows through the three main lakes - Athabasca, Great Slave Lake and Great Bear Lake (Kite et al, 1994). These lakes occupy an area of 65,000 sq km but little gauge information is available. The levels of the lakes are only measured at a few points on the circumferences and river flows are only measured downstream. The hydraulic relationships between level/discharge and level/area/volume are uncertain. It has been previously shown that satellite remote sensing can be utilised in providing measurements of both lake surface area using imaging techniques and lake level using radar altimetry (Birkett, 1994). Here, we explore the application of these techniques to derive the lake levels and areas for the Mackenzie Basin lakes.

  9. Lake-sediment evidence for the date of deglaciation of the Hidden Lake area, Kenai Peninsula, Alaska

    NASA Astrophysics Data System (ADS)

    Rymer, Michael J.; Sims, John D.

    1982-06-01

    An abrupt environmental change is reflected in a core from Hidden Lake, Alaska, by differences in sediment type, chlorite crystallinity, and content of organic carbon and water of the sediments. This abrupt change in the sedimentary record occurred about 14,500 14C yr ago and probably marks the time of recession of the glacier from the Hidden Lake drainage basin. Deglaciation of the area was then underway, and rock flour was being deposited in the lake. After recession of the glacier from the Hidden Lake drainage basin, rock flour was no longer introduced, and organic-matter content of the sediment increased. By the dating of these changes in sediment type, we show that retreat of glaciers in this area took place significantly earlier than previously estimated; this agrees with the timing of retreat of alpine glaciers elsewhere in western North America.

  10. Trampling impacts on thermotolerant vegetation of geothermal areas in New Zealand.

    PubMed

    Burns, Bruce R; Ward, Jonet; Downs, Theresa M

    2013-12-01

    Geothermal features such as geysers, mud pools, sinter terraces, fumaroles, hot springs, and steaming ground are natural attractions often visited by tourists. Visitation rates for such areas in the Taupo Volcanic Zone of New Zealand are in the order of hundreds of thousands annually. These areas are also habitat for rare and specialized plant and microbial communities that live in the steam-heated soils of unusual chemical composition. We evaluated historical and current trampling impacts of tourists on the thermotolerant vegetation of the Waimangu and Waiotapu geothermal areas near Rotorua, and compared the results to experimental trampling at a third site (Taheke) not used by tourists. Historical tourism has removed vegetation and soil from around key features, and remaining subsoil is compacted into an impervious pavement on which vegetation recolonization is unlikely in the short term. Social tracks made by tourists were present at both tourist sites often leading them onto hotter soils than constructed tracks. Vegetation height and cover were lower on and adjacent to social tracks than further from them. Thermotolerant vegetation showed extremely low resistance to experimental trampling. This confirms and extends previous research that also shows that thallophytes and woody shrubs, life forms that dominate in thermotolerant vegetation, are vulnerable to trampling damage. Preservation of these vulnerable ecosystems must ensure that tourist traffic is confined to existing tracks or boardwalks, and active restoration of impacted sites may be warranted.

  11. Trampling Impacts on Thermotolerant Vegetation of Geothermal Areas in New Zealand

    NASA Astrophysics Data System (ADS)

    Burns, Bruce R.; Ward, Jonet; Downs, Theresa M.

    2013-12-01

    Geothermal features such as geysers, mud pools, sinter terraces, fumaroles, hot springs, and steaming ground are natural attractions often visited by tourists. Visitation rates for such areas in the Taupo Volcanic Zone of New Zealand are in the order of hundreds of thousands annually. These areas are also habitat for rare and specialized plant and microbial communities that live in the steam-heated soils of unusual chemical composition. We evaluated historical and current trampling impacts of tourists on the thermotolerant vegetation of the Waimangu and Waiotapu geothermal areas near Rotorua, and compared the results to experimental trampling at a third site (Taheke) not used by tourists. Historical tourism has removed vegetation and soil from around key features, and remaining subsoil is compacted into an impervious pavement on which vegetation recolonization is unlikely in the short term. Social tracks made by tourists were present at both tourist sites often leading them onto hotter soils than constructed tracks. Vegetation height and cover were lower on and adjacent to social tracks than further from them. Thermotolerant vegetation showed extremely low resistance to experimental trampling. This confirms and extends previous research that also shows that thallophytes and woody shrubs, life forms that dominate in thermotolerant vegetation, are vulnerable to trampling damage. Preservation of these vulnerable ecosystems must ensure that tourist traffic is confined to existing tracks or boardwalks, and active restoration of impacted sites may be warranted.

  12. Development situation and prospecting division of geothermal resources in Yangshan county, Guangdong Province

    NASA Astrophysics Data System (ADS)

    Yin, Lijun; Luo, Yizhen; Ma, Huiying; Xie, Yanxiao; Liu, Zhenzhen

    2017-03-01

    Yangshan County has abundant low-geothermal resources in its northeast, southwest, and midwest regions. These low-temperature geothermal resources in Yangshan County can prove to be beneficial for different purposes such as tourism, recuperation, sauna, and agriculture. Thirteen geothermal hot springs (spots) and seven geothermal anomalies have been discovered till now in this area. The geothermal resources are grouped on the basis of their conditions as follows: The Chengjia-Dianzhan and Dongguan-Jietan geothermal areas are classified as priority development zones, the Huangben-Mazishui and Qigongyuntankeng areas as sub-priority development zones, the Jiangying geothermal area as a general development zone, the Yangshan geothermal area as a potential development zone, and the Chengjia and Longfeng geothermal areas as restricted development zones.

  13. Geothermal pilot study final report: creating an international geothermal energy community

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bresee, J.C.; Yen, W.W.S.; Metzler, J.E.

    The Geothermal Pilot Study under the auspices of the Committee on the Challenges of Modern Society (CCMS) was established in 1973 to apply an action-oriented approach to international geothermal research and development, taking advantage of the established channels of governmental communication provided by the North Atlantic Treaty Organization (NATO). The Pilot Study was composed of five substudies. They included: computer-based information systems; direct application of geothermal energy; reservoir assessment; small geothermal power plants; and hot dry rock concepts. The most significant overall result of the CCMS Geothermal Pilot Study, which is now complete, is the establishment of an identifiable communitymore » of geothermal experts in a dozen or more countries active in development programs. Specific accomplishments include the creation of an international computer file of technical information on geothermal wells and fields, the development of studies and reports on direct applications, geothermal fluid injection and small power plants, and the operation of the visiting scientist program. In the United States, the computer file has aready proven useful in the development of reservoir models and of chemical geothermometers. The state-of-the-art report on direct uses of geothermal energy is proving to be a valuable resource document for laypersons and experts in an area of increasing interest to many countries. Geothermal fluid injection studies in El Salvador, New Zealand, and the United States have been assisted by the Reservoir Assessment Substudy and have led to long-range reservoir engineering studies in Mexico. At least seven small geothermal power plants are in use or have been planned for construction around the world since the Small Power Plant Substudy was instituted--at least partial credit for this increased application can be assigned to the CCMS Geothermal Pilot Study. (JGB)« less

  14. Leasing of federal geothermal resources

    NASA Technical Reports Server (NTRS)

    Stone, R. T.

    1974-01-01

    Pursuant to the Geothermal Steam Act of 1970 and the regulations published on December 21, 1973, the first Federal geothermal competitive lease sale was held on January 22, 1974, by the Department of the Interior, offering 33 tracts totalling over 50,000 acres in three Known Geothermal Resource Areas in California. On January 1, 1974, Federal lands outside Known Geothermal Resource Areas were opened to noncompetitive lease applications, of which, 3,763 had been received by June 1, 1974. During fiscal year 1974, a total of 22 competitive leases had been issued in California and Oregon. The principal components in the Department involved in the leasing program are the Geological Survey and the Bureau of Land Management. The former has jurisdiction over drilling and production operations and other activities in the immediate area of operations. The latter receives applications and issues leases and is responsible for managing leased lands under its jurisdiction outside the area of operations. The interrelationships of the above agencies and the procedures in the leasing program are discussed.

  15. Modelling geothermal conditions in part of the Szczecin Trough - the Chociwel area

    NASA Astrophysics Data System (ADS)

    Miecznik, Maciej; Sowiżdżał, Anna; Tomaszewska, Barbara; Pająk, Leszek

    2015-09-01

    The Chociwel region is part of the Szczecin Trough and constitutes the northeastern segment of the extended Szczecin-Gorzów Synclinorium. Lower Jurassic reservoirs of high permeability of up to 1145 mD can discharge geothermal waters with a rate exceeding 250 m3/h and temperatures reach over 90°C in the lowermost part of the reservoirs. These conditions provide an opportunity to generate electricity from heat accumulated in geothermal waters using binary ORC (Organic Rankine Cycle) systems. A numerical model of the natural state and exploitation conditions was created for the Chociwel area with the use of TOUGH2 geothermal simulator (i.e., integral finite-difference method). An analysis of geological and hydrogeothermal data indicates that the best conditions are found to the southeast of the town of Chociwel, where the bottom part of the reservoir reaches 3 km below ground. This would require drilling two new wells, namely one production and one injection. Simulated production with a flow rate of 275 m3/h, a temperature of 89°C at the wellhead, 30°C injection temperature and wells being 1.2 km separated from each other leads to a small temperature drop and moderate requirements for pumping power over a 50 years' time span. The ORC binary system can produce at maximum 592.5 kW gross power with the R227ea found as the most suitable working fluid. Geothermal brine leaving the ORC system with a temperature c. 53°C can be used for other purposes, namely mushroom growing, balneology, swimming pools, soil warming, de-icing, fish farming and for heat pumps.

  16. Geologic Map of Mount Mazama and Crater Lake Caldera, Oregon

    USGS Publications Warehouse

    Bacon, Charles R.

    2008-01-01

    Crater Lake partly fills one of the most spectacular calderas of the world, an 8-by-10-km basin more than 1 km deep formed by collapse of the volcano known as Mount Mazama (fig. 1) during a rapid series of explosive eruptions about 7,700 years ago. Having a maximum depth of 594 m, Crater Lake is the deepest lake in the United States. Crater Lake National Park, dedicated in 1902, encompasses 645 km2 of pristine forested and alpine terrain, including the lake itself, virtually all of Mount Mazama, and most of the area of the geologic map. The geology of the area was first described in detail by Diller and Patton (1902) and later by Williams (1942), whose vivid account led to international recognition of Crater Lake as the classic collapse caldera. Because of excellent preservation and access, Mount Mazama, Crater Lake caldera, and the deposits formed by the climactic eruption constitute a natural laboratory for study of volcanic and magmatic processes. For example, the climactic ejecta are renowned among volcanologists as evidence for systematic compositional zonation within a subterranean magma chamber. Mount Mazama's climactic eruption also is important as the source of the widespread Mazama ash, a useful Holocene stratigraphic marker throughout the Pacific Northwest, adjacent Canada, and offshore. A detailed bathymetric survey of the floor of Crater Lake in 2000 (Bacon and others, 2002) provides a unique record of postcaldera eruptions, the interplay between volcanism and filling of the lake, and sediment transport within this closed basin. Knowledge of the geology and eruptive history of the Mount Mazama edifice, greatly enhanced by the caldera wall exposures, gives exceptional insight into how large volcanoes of magmatic arcs grow and evolve. Lastly, the many smaller volcanoes of the High Cascades beyond the limits of Mount Mazama are a source of information on the flux of mantle-derived magma through the region. General principles of magmatic and eruptive

  17. A conceptual geochemical model of the geothermal system at Surprise Valley, CA

    NASA Astrophysics Data System (ADS)

    Fowler, Andrew P. G.; Ferguson, Colin; Cantwell, Carolyn A.; Zierenberg, Robert A.; McClain, James; Spycher, Nicolas; Dobson, Patrick

    2018-03-01

    Characterizing the geothermal system at Surprise Valley (SV), northeastern California, is important for determining the sustainability of the energy resource, and mitigating hazards associated with hydrothermal eruptions that last occurred in 1951. Previous geochemical studies of the area attempted to reconcile different hot spring compositions on the western and eastern sides of the valley using scenarios of dilution, equilibration at low temperatures, surface evaporation, and differences in rock type along flow paths. These models were primarily supported using classical geothermometry methods, and generally assumed that fluids in the Lake City mud volcano area on the western side of the valley best reflect the composition of a deep geothermal fluid. In this contribution, we address controls on hot spring compositions using a different suite of geochemical tools, including optimized multicomponent geochemistry (GeoT) models, hot spring fluid major and trace element measurements, mineralogical observations, and stable isotope measurements of hot spring fluids and precipitated carbonates. We synthesize the results into a conceptual geochemical model of the Surprise Valley geothermal system, and show that high-temperature (quartz, Na/K, Na/K/Ca) classical geothermometers fail to predict maximum subsurface temperatures because fluids re-equilibrated at progressively lower temperatures during outflow, including in the Lake City area. We propose a model where hot spring fluids originate as a mixture between a deep thermal brine and modern meteoric fluids, with a seasonally variable mixing ratio. The deep brine has deuterium values at least 3 to 4‰ lighter than any known groundwater or high-elevation snow previously measured in and adjacent to SV, suggesting it was recharged during the Pleistocene when meteoric fluids had lower deuterium values. The deuterium values and compositional characteristics of the deep brine have only been identified in thermal springs and

  18. 3D Model of the Neal Hot Springs Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    The Neal Hot Springs geothermal system lies in a left-step in a north-striking, west-dipping normal fault system, consisting of the Neal Fault to the south and the Sugarloaf Butte Fault to the north (Edwards, 2013). The Neal Hot Springs 3D geologic model consists of 104 faults and 13 stratigraphic units. The stratigraphy is sub-horizontal to dipping <10 degrees and there is no predominant dip-direction. Geothermal production is exclusively from the Neal Fault south of, and within the step-over, while geothermal injection is into both the Neal Fault to the south of the step-over and faults within the step-over.

  19. Detecting geothermal anomalies and evaluating LST geothermal component by combining thermal remote sensing time series and land surface model data

    USGS Publications Warehouse

    Romaguera, Mireia; Vaughan, R. Greg; Ettema, J.; Izquierdo-Verdiguier, E.; Hecker, C. A.; van der Meer, F.D.

    2018-01-01

    This paper explores for the first time the possibilities to use two land surface temperature (LST) time series of different origins (geostationary Meteosat Second Generation satellite data and Noah land surface modelling, LSM), to detect geothermal anomalies and extract the geothermal component of LST, the LSTgt. We hypothesize that in geothermal areas the LSM time series will underestimate the LST as compared to the remote sensing data, since the former does not account for the geothermal component in its model.In order to extract LSTgt, two approaches of different nature (physical based and data mining) were developed and tested in an area of about 560 × 560 km2 centered at the Kenyan Rift. Pre-dawn data in the study area during the first 45 days of 2012 were analyzed.The results show consistent spatial and temporal LSTgt patterns between the two approaches, and systematic differences of about 2 K. A geothermal area map from surface studies was used to assess LSTgt inside and outside the geothermal boundaries. Spatial means were found to be higher inside the geothermal limits, as well as the relative frequency of occurrence of high LSTgt. Results further show that areas with strong topography can result in anomalously high LSTgt values (false positives), which suggests the need for a slope and aspect correction in the inputs to achieve realistic results in those areas. The uncertainty analysis indicates that large uncertainties of the input parameters may limit detection of LSTgt anomalies. To validate the approaches, higher spatial resolution images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data over the Olkaria geothermal field were used. An established method to estimate radiant geothermal flux was applied providing values between 9 and 24 W/m2 in the geothermal area, which coincides with the LSTgt flux rates obtained with the proposed approaches.The proposed approaches are a first step in estimating LSTgt

  20. The Hengill geothermal area, Iceland: variation of temperature gradients deduced from the maximum depth of seismogenesis

    USGS Publications Warehouse

    Foulger, G.R.

    1995-01-01

    Given a uniform lithology and strain rate and a full seismic data set, the maximum depth of earthquakes may be viewed to a first order as an isotherm. These conditions are approached at the Hengill geothermal area, S. Iceland, a dominantly basaltic area. The temperature at which seismic failure ceases for the strain rates likely at the Hengill geothermal area is determined by analogy with oceanic crust, and is about 650 ?? 50??C. The topographies of the top and bottom of the seismogenic layer were mapped using 617 earthquakes. The thickness of the seismogenic layer is roughly constant and about 3 km. A shallow, aseismic, low-velocity volume within the spreading plate boundary that crosses the area occurs above the top of the seismogenic layer and is interpreted as an isolated body of partial melt. The base of the seismogenic layer has a maximum depth of about 6.5 km beneath the spreading axis and deepens to about 7 km beneath a transform zone in the south of the area. -from Author

  1. Pumpernickel Valley Geothermal Project Thermal Gradient Wells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Z. Adam Szybinski

    2006-01-01

    The Pumpernickel Valley geothermal project area is located near the eastern edge of the Sonoma Range and is positioned within the structurally complex Winnemucca fold and thrust belt of north-central Nevada. A series of approximately north-northeast-striking faults related to the Basin and Range tectonics are superimposed on the earlier structures within the project area, and are responsible for the final overall geometry and distribution of the pre-existing structural features on the property. Two of these faults, the Pumpernickel Valley fault and Edna Mountain fault, are range-bounding and display numerous characteristics typical of strike-slip fault systems. These characteristics, when combined withmore » geophysical data from Shore (2005), indicate the presence of a pull-apart basin, formed within the releasing bend of the Pumpernickel Valley – Edna Mountain fault system. A substantial body of evidence exists, in the form of available geothermal, geological and geophysical information, to suggest that the property and the pull-apart basin host a structurally controlled, extensive geothermal field. The most evident manifestations of the geothermal activity in the valley are two areas with hot springs, seepages, and wet ground/vegetation anomalies near the Pumpernickel Valley fault, which indicate that the fault focuses the fluid up-flow. There has not been any geothermal production from the Pumpernickel Valley area, but it was the focus of a limited exploration effort by Magma Power Company. In 1974, the company drilled one exploration/temperature gradient borehole east of the Pumpernickel Valley fault and recorded a thermal gradient of 160oC/km. The 1982 temperature data from five unrelated mineral exploration holes to the north of the Magma well indicated geothermal gradients in a range from 66 to 249oC/km for wells west of the fault, and ~283oC/km in a well next to the fault. In 2005, Nevada Geothermal Power Company drilled four geothermal gradient wells

  2. Mapping temperature and radiant geothermal heat flux anomalies in the Yellowstone geothermal system using ASTER thermal infrared data

    USGS Publications Warehouse

    Vaughan, R. Greg; Lowenstern, Jacob B.; Keszthelyi, Laszlo P.; Jaworowski, Cheryl; Heasler, Henry

    2012-01-01

    The purpose of this work was to use satellite-based thermal infrared (TIR) remote sensing data to measure, map, and monitor geothermal activity within the Yellowstone geothermal area to help meet the missions of both the U.S. Geological Survey Yellowstone Volcano Observatory and the Yellowstone National Park Geology Program. Specifically, the goals were to: 1) address the challenges of remotely characterizing the spatially and temporally dynamic thermal features in Yellowstone by using nighttime TIR data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and 2) estimate the temperature, geothermal radiant emittance, and radiant geothermal heat flux (GHF) for Yellowstone’s thermal areas (both Park wide and for individual thermal areas). ASTER TIR data (90-m pixels) acquired at night during January and February, 2010, were used to estimate surface temperature, radiant emittance, and radiant GHF from all of Yellowstone’s thermal features, produce thermal anomaly maps, and update field-based maps of thermal areas. A background subtraction technique was used to isolate the geothermal component of TIR radiance from thermal radiance due to insolation. A lower limit for the Yellowstone’s total radiant GHF was established at ~2.0 GW, which is ~30-45% of the heat flux estimated through geochemical (Cl-flux) methods. Additionally, about 5 km2 was added to the geodatabase of mapped thermal areas. This work provides a framework for future satellite-based thermal monitoring at Yellowstone as well as exploration of other volcanic / geothermal systems on a global scale.

  3. Potential area for floating net fishery in Lake Toba

    NASA Astrophysics Data System (ADS)

    Rustini, H. A.; Harsono, E.; Ridwansyah, I.

    2018-02-01

    Lake Toba in North Sumatera, Indonesia, is now designated to be a world-class tourism destination. Aside from its infrastructure development, this largest lake in the Southeast Asia needs to be restored, especially its water quality. While an oligotrophic status is required for tourism purposes, several studies showed that Toba is mesotrophic at its best and hyper-eutrophic at its worst. Numerous studies and reports blame floating net fishery (FNF) for water quality decline in Lake Toba and propose limitation for its production. While the central government allowed FNF to be positioned in certain areas according to its depth and distance from the lakeshore, increasing number of FNF means adding more nutrients to the lake and thus may inhibit the lake’s restoration process. Hence, it is important to identify which areas are potential for FNF location to assist the authorities to regulate FNF. This study used SPOT-6, SPOT-7, and Pleiades satellite imagery to locate the position of existing FNF and to analyse the result to identify a potential location for FNF.

  4. Relative Contributions of Geothermal Pumping and Long-Term Earthquake Rate to Seismicity at California Geothermal Fields

    NASA Astrophysics Data System (ADS)

    Weiser, D. A.; Jackson, D. D.

    2015-12-01

    In a tectonically active area, a definitive discrimination between geothermally-induced and tectonic earthquakes is difficult to achieve. We focus our study on California's 11 major geothermal fields: Amedee, Brawley, Casa Diablo, Coso, East Mesa, The Geysers, Heber, Litchfield, Salton Sea, Susanville, and Wendel. The Geysers geothermal field is the world's largest geothermal energy producer. California's Department of Oil Gas and Geothermal Resources provides field-wide monthly injection and production volumes for each of these sites, which allows us to study the relationship between geothermal pumping activities and seismicity. Since many of the geothermal fields began injecting and producing before nearby seismic stations were installed, we use smoothed seismicity since 1932 from the ANSS catalog as a proxy for tectonic earthquake rate. We examine both geothermal pumping and long-term earthquake rate as factors that may control earthquake rate. Rather than focusing only on the largest earthquake, which is essentially a random occurrence in time, we examine how M≥4 earthquake rate density (probability per unit area, time, and magnitude) varies for each field. We estimate relative contributions to the observed earthquake rate of M≥4 from both a long-term earthquake rate (Kagan and Jackson, 2010) and pumping activity. For each geothermal field, respective earthquake catalogs (NCEDC and SCSN) are complete above at least M3 during the test period (which we tailor to each site). We test the hypothesis that the observed earthquake rate at a geothermal site during the test period is a linear combination of the long-term seismicity and pumping rates. We use a grid search to determine the confidence interval of the weighting parameters.

  5. Idaho Geothermal Commercialization Program. Idaho geothermal handbook

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hammer, G.D.; Esposito, L.; Montgomery, M.

    The following topics are covered: geothermal resources in Idaho, market assessment, community needs assessment, geothermal leasing procedures for private lands, Idaho state geothermal leasing procedures - state lands, federal geothermal leasing procedures - federal lands, environmental and regulatory processes, local government regulations, geothermal exploration, geothermal drilling, government funding, private funding, state and federal government assistance programs, and geothermal legislation. (MHR)

  6. Geothermal Project Consulting | Geothermal Technologies | NREL

    Science.gov Websites

    Geothermal Project Consulting Geothermal Project Consulting When consulting on projects, NREL focuses on identifying specific barriers or challenges that are likely to impact geothermal project , validation, and deployment of geothermal technologies Assess and evaluate geothermal R&D projects

  7. Geology of the Pavana geothermal area, Departamento de Choluteca, Honduras, Central America: Field report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eppler, D.B.; Heiken, G.; Wohletz, K.

    The Pavana geothermal area is located in southern Honduras near the Gulf of Fonseca. This region is underlain by late Tertiary volcanic rocks. Within ranges near the geothermal manifestations, the rock sequences is characterized by intermediate to mafic laharic breccias and lavas overlain by silicic tuffs and lavas, which are in turn overlain by intermediate to mafic breccias, lavas, and tuffs. The nearest Quaternary volcanoes are about 40 km to the southwest, where the chain of active Central American volcanoes crosses the mouth of the Gulf of Fonseca. Structure of the Pavana area is dominated by generally northwest-trending, southwest-dipping normalmore » faults. This structure is topographically expressed as northwest-trending escarpments that bound blocks of bedrock separated by asymmetric valleys that contain thin alluvial deposits. Thermal waters apparently issue from normal faults and are interpreted as having been heated during deep circulation along fault zones within a regional environment of elevated heat flow. Natural outflow from the main thermal area is about 3000 l/min of 60/sup 0/C water. Geothermometry of the thermal waters suggests a reservoir base temperature of about 150/sup 0/C.« less

  8. Study of the wide area of a lake with remote sensing

    NASA Astrophysics Data System (ADS)

    Lazaridou, Maria A.; Karagianni, Aikaterini C.

    2016-08-01

    Water bodies are particularly important for environment and development issues. Their study requires multiple information. Remote sensing has been proven useful in the above study. This paper concerns the wide area of Lake Orestiada in the region of Western Macedonia in Greece. The area is of particular interest because Lake Orestiada is included in the Natura 2000 network and is surrounded by diverse landcovers as built up areas and agricultural land. Multispectral and thermal Landsat 5 satellite images of two time periods are being used. Their processing is being done by Erdas Imagine software. The general physiognomy of the area and the lake shore are examined after image enhancement techniques and image interpretation. Directions of the study concern geomorphological aspects, land covers, estimation of surface temperature as well as changes through time.

  9. The Colorado School of Mines Nevada geothermal study

    NASA Technical Reports Server (NTRS)

    Keller, G. V.; Grose, L. T.; Crewpson, R. A.

    1974-01-01

    Geothermal systems in the Basin and Range Province of the western United States probably differ in many respects from geothermal systems already discovered in other parts of the world because of the unique tectonic setting. To investigate this, a study of the geothermal occurrences at Fly Ranch, approximately 100 miles north of Reno, Nevada, has been undertaken. Ample evidence for a geothermal system exists in this area, including the surface expression of heat flow in the form of hot springs, an extensive area of low electrical resistivity, and a high level of seismicity along faults bounding the thermal area. However, geophysical and geological studies have not yet provided evidence for a local heat source at depth. Additional detailed geophysical and geological studies, as well as drilling, must be completed before the geothermal system can be described fully.

  10. Extraction and representation of nested catchment areas from digital elevation models in lake-dominated topography

    NASA Astrophysics Data System (ADS)

    Mackay, D. Scott; Band, Lawrence E.

    1998-04-01

    This paper presents a new method for extracting flow directions, contributing (upslope) areas, and nested catchments from digital elevation models in lake-dominated areas. Existing tools for acquiring descriptive variables of the topography, such as surface flow directions and contributing areas, were developed for moderate to steep topography. These tools are typically difficult to apply in gentle topography owing to limitations in explicitly handling lakes and other flat areas. This paper addresses the problem of accurately representing general topographic features by first identifying distinguishing features, such as lakes, in gentle topography areas and then using these features to guide the search for topographic flow directions and catchment marking. Lakes are explicitly represented in the topology of a watershed for use in water routing. Nonlake flat features help guide the search for topographic flow directions in areas of low signal to noise. This combined feature-based and grid-based search for topographic features yields improved contributing areas and watershed boundaries where there are lakes and other flat areas. Lakes are easily classified from remotely sensed imagery, which makes automated representation of lakes as subsystems within a watershed system tractable with widely available data sets.

  11. Slip and Dilation Tendency Analysis of the San Emidio Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes

  12. Slip and Dilation Tendency Anlysis of McGinness Hills Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    Slip and Dilation Tendency in focus areas Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998

  13. BUCKS LAKE AND CHIPS CREEK ROADLESS AREAS, CALIFORNIA.

    USGS Publications Warehouse

    Sorensen, Martin L.; Linne, J. Mitchell

    1984-01-01

    The results of a mineral-resource assessment of the Bucks Lake and Chips Creek Roadless Areas, California indicate several areas with mineral-resource potential. The presence or absence of these potentially auriferous deposits can best be determined by drilling through the relatively thin cover of volcanic rocks.

  14. The significance of "geothermal microzonation" for the correct planning of low-grade source geothermal systems

    NASA Astrophysics Data System (ADS)

    Viccaro, Marco; Pezzino, Antonino; Belfiore, Giuseppe Maria; Campisano, Carlo

    2016-04-01

    Despite the environmental-friendly energy systems are solar thermal technologies, photovoltaic and wind power, other advantageous technologies exist, although they have not found wide development in countries such as Italy. Given the almost absent environmental impact and the rather favorable cost/benefit ratio, low-enthalpy geothermal systems are, however, likely to be of strategic importance also in Italy during the next years. The importance of geology for a sustainable exploitation of the ground through geothermal systems from low-grade sources is becoming paramount. Specifically, understanding of the lithological characteristics of the subsurface along with structures and textures of rocks is essential for a correct planning of the probe/geo-exchanger field and their associated ground source heat pumps. The complex geology of Eastern Sicily (Southern Italy), which includes volcanic, sedimentary and metamorphic units over limited extension, poses the question of how thermal conductivity of rocks is variable at the scale of restricted areas (even within the same municipality). This is the innovative concept of geothermal microzonation, i.e., how variable is the geothermal potential as a function of geology at the microscale. Some pilot areas have been therefore chosen to test how the geological features of the subsurface can influence the low-enthalpy geothermal potential of an area. Our geologically based evaluation and micro-zonation of the low-grade source geothermal potential of the selected areas have been verified to be fundamental for optimization of all the main components of a low-enthalpy geothermal system. Saving realization costs and limiting the energy consumption through correct sizing of the system are main ambitions to have sustainable development of this technology with intensive utilization of the subsurface. The variegated territory of countries such as Italy implies that these goals can be only reached if, primarily, the geological features

  15. Geothermal handbook

    USGS Publications Warehouse

    1976-01-01

    The Bureau of Land Management offered over 400,000 hectares (one million acres) for geothermal exploration and development in 1975, and figure is expected to double this year. The Energy Research and Development Administration hopes for 10-15,000 megawatts of geothermal energy by 1985, which would require, leasing over 16.3 million hectares (37 million acres) of land, at least half of which is federal land. Since there is an 8 to 8-1/2 year time laf between initial exploration and full field development, there would have to be a ten-fold increase in the amount of federal land leased within the next three years. Seventy percent of geothermal potential, 22.3 million hectares (55 million acres), is on federal lands in the west. The implication for the Service are enormous and the problems immediate. Geothermal resource are so widespread they are found to some extent in most biomes and ecosystems in the western United States. In most cases exploitation and production of geothermal resources can be made compatible with fish and wildlife management without damage, if probable impacts are clearly understood and provided for before damage has unwittingly been allowed to occur. Planning for site suitability and concern with specific operating techniques are crucial factors. There will be opportunities for enhancement: during exploration and testing many shallow groundwater bodies may be penetrated which might be developed for wildlife use. Construction equipment and materials needed for enhancement projects will be available in areas heretofore considered remote projects will be available in areas heretofore considered remote by land managers. A comprehensive knowledge of geothermal development is necessary to avoid dangers and seize opportunities. This handbook is intended to serve as a working tool in the field. It anticipated where geothermal resource development will occur in the western United States in the near future. A set of environmental assessment procedures are

  16. Volcano-tectonic structures, gravity and helium in geothermal areas of Tuscany and Latium (Vulsini volcanic district), Italy

    USGS Publications Warehouse

    Di, Filippo M.; Lombardi, S.; Nappi, G.; Reimer, G.M.; Renzulli, A.; Toro, B.

    1999-01-01

    Since the early 1980s, geological and structural mapping, gravity, and helium soil-gas studies have been performed in the eastern sector of the Vulsini Volcanic District (Roman Magmatic Province) in an attempt to locate potential geothermal reservoirs. This area is characterised by an anomalous geothermal gradient of > 100??C/km, and by widespread hydrothermal mineralization, thermal springs, high gas fluxes, and fossil and current travertine deposits. The results of these surveys indicate the existence of a number of fault systems, with N-S and E-W structures that appear to be superimposed on older NW-SE and NE-SW features. Comparison of the results of the various studies also reveals differences in permeability and potential reservoir structures at depth.Since the early 1980s, geological and structural mapping, gravity, and helium soil-gas studies have been performed in the eastern sector of the Vulsini Volcanic District (Roman Magmatic Province) in an attempt to locate potential geothermal reservoirs. This area is characterised by an anomalous geothermal gradient of > 100??C/km, and by widespread hydrothermal mineralization, thermal springs, high gas fluxes, and fossil and current travertine deposits. The results of these surveys indicate the existence of a number of fault systems, with N-S and E-W structures that appear to be superimposed on older NW-SE and NE-SW features. Comparison of the results of the various studies also reveals differences in permeability and potential reservoir structures at depth.

  17. Special places in the Lake Calumet area.

    Treesearch

    Herbert W. Schroeder

    2004-01-01

    An open-ended, qualitative survey was conducted to identify special places in the Lake Calumet area of northeastern Illinois and northwestern Indiana, and to learn what kinds of experiences and environmental features make these places memorable and important to people.

  18. The use of total lake-surface area as an indicator of climatic change: Examples from the Lahontan basin

    USGS Publications Warehouse

    Benson, L.V.; Paillet, Frederick L.

    1989-01-01

    Variation in the size of lakes in the Lahontan basin is topographically constrained. River diversion also has played a major role in regulating lake size in Lahontan subbasins. The proper gage of lake response to change in the hydrologic balance is neither lake depth (level) nor lake volume but instead lake-surface area. Normalization of surface area is necessary when comparing surface areas of lakes in basins having different topographies. To a first approximation, normalization can be accomplished by dividing the paleosurface area of a lake by its mean-historical, reconstructed surface area. ?? 1989.

  19. Research status of geothermal resources in China

    NASA Astrophysics Data System (ADS)

    Zhang, Lincheng; Li, Guang

    2017-08-01

    As the representative of the new green energy, geothermal resources are characterized by large reserve, wide distribution, cleanness and environmental protection, good stability, high utilization factor and other advantages. According to the characteristics of exploitation and utilization, they can be divided into high-temperature, medium-temperature and low-temperature geothermal resources. The abundant and widely distributed geothermal resources in China have a broad prospect for development. The medium and low temperature geothermal resources are broadly distributed in the continental crustal uplift and subsidence areas inside the plate, represented by the geothermal belt on the southeast coast, while the high temperature geothermal resources concentrate on Southern Tibet-Western Sichuan-Western Yunnan Geothermal Belt and Taiwan Geothermal Belt. Currently, the geothermal resources in China are mainly used for bathing, recuperation, heating and power generation. It is a country that directly makes maximum use of geothermal energy in the world. However, China’s geothermal power generation, including installed generating capacity and power generation capacity, are far behind those of Western European countries and the USA. Studies on exploitation and development of geothermal resources are still weak.

  20. Relationship of geological and geothermal field properties: Midcontinent area, USA, an example

    USGS Publications Warehouse

    Forster, A.; Merriam, D.F.; Brower, J.C.

    1993-01-01

    negative or slightly positive. These results are clearly shown by the cluster analysis and the principal components. Considering a close relationship between temperature and thermal conductivity of the sediments as observed for most of the Midcontinent area and relatively homogeneous heat-flow density conditions for the study area these results support the following assumptions: (1) undifferentiated geothermal gradients, computed from temperatures of different depth intervals and differing sediment properties, cannot contribute to an improved understanding of the temperature structure and its controls within the sedimentary cover, and (2) the quantitative approach of revealing such relations needs refined datasets of temperature information valid for the different depth levels or stratigraphic units. ?? 1993 International Association for Mathematical Geology.

  1. ROUND LAKE WILDERNESS STUDY AREA, WISCONSIN.

    USGS Publications Warehouse

    Cannon, W.F.; Williams, Bradford B.

    1984-01-01

    The Round Lake Wilderness study area in Wisconsin was studied using geophysical and geochemical surveys, examination of a few bedrock exposures near the area (none are known within the area) and augering and testing of peat deposits. The only direct indication of potential mineral resource is about 760,000 tons of commercial quality peat contained in several bogs. Larger deposits of similar material are abundant closer to markets and although the peat in this area is classified as a demonstrated resource within an area of substantiated peat resource potential, it is considered to be of little importance. The study area lies within a belt of ancient volcanic rocks extending across northern Wisconsin in which several important copper, zinc, and lead deposits were discovered but no indication of such deposits was found within the area.

  2. 75 FR 22228 - Regulated Navigation Area; Lake Champlain Bridge Construction Zone, NY and VT

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-28

    ...-AA11 Regulated Navigation Area; Lake Champlain Bridge Construction Zone, NY and VT AGENCY: Coast Guard... establishing a regulated navigation area around the construction zone of the Lake Champlain Bridge between... on all vessels transiting the navigable waters of Lake Champlain in the vicinity of the bridge...

  3. Lakes in the greater Denver area, Front Range Urban Corridor

    USGS Publications Warehouse

    Danielson, T.W.

    1975-01-01

    The purpose of this report is to present the results of an inventory of the lakes in the central one-third of the Colorado Front Range Urban Corridor. This inventory provides information that might be helpful in planning the best and most beneficial use of lakes in an area of rapid population growth. The report includes data on lake size and water quality. Size data are included on most of the lakes of 2 hectares (20,000 m2, or about 5 acres) or greater, and water-quality data are provided on most lakes larger than 10 hectares (about 25 acres). Bodies of water resulting form excavation of gravel (borrow pits) were generally not included in the inventory.

  4. Hydrothermal fluids circulation and travertine deposition in an active tectonic setting: Insights from the Kamara geothermal area (western Anatolia, Turkey)

    NASA Astrophysics Data System (ADS)

    Brogi, Andrea; Alçiçek, M. Cihat; Yalçıner, Cahit Çağlar; Capezzuoli, Enrico; Liotta, Domenico; Meccheri, Marco; Rimondi, Valentina; Ruggieri, Giovanni; Gandin, Anna; Boschi, Chiara; Büyüksaraç, Aydin; Alçiçek, Hülya; Bülbül, Ali; Baykara, Mehmet Oruç; Shen, Chuan-Chou

    2016-06-01

    Coexistence of thermal springs, travertine deposits and tectonic activity is a recurring feature for most geothermal areas. Although such a certainty, their relationships are debated mainly addressing on the role of the tectonic activity in triggering and controlling fluids flow and travertine deposition. In this paper, we present the results of an integrated study carried out in a geothermal area located in western Anatolia (Turkey), nearby the well-known Pamukkale area (Denizli Basin). Our study focused on the relationships among hydrothermal fluids circulation, travertine deposition and tectonic activity, with particular emphasis on the role of faults in controlling fluids upwelling, thermal springs location and deposition of travertine masses. New field mapping and structural/kinematics analyses allowed us to recognize two main faults systems (NW- and NE-trending), framed in the Neogene-Quaternary extensional tectonic evolution of western Anatolia. A geo-radar (GPR) prospection was also provided in a key-area, permitting us to reconstruct a buried fault zone and its relationships with the development of a fissure-ridge travertine deposit (Kamara fissure-ridge). The integration among structural and geophysical studies, fluids inclusion, geochemical, isotopic data and 230 Th/238 U radiometric age determination on travertine deposits, depict the characteristics of the geothermal fluids and their pathway, up to the surface. Hydrological and seismological data have been also taken in account to investigate the relation between local seismicity and fluid upwelling. As a main conclusion we found strict relationships among tectonic activity, earthquakes occurrence, and variation of the physical/chemical features of the hydrothermal fluids, presently exploited at depth, or flowing out in thermal springs. In the same way, we underline the tectonic role in controlling the travertine deposition, making travertine (mainly banded travertine) a useful proxy to reconstruct the

  5. Compensated geothermal gradient: new map of old data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ibrahim, M.W.

    1986-05-01

    Bottom-hole temperature measurement is one of the oldest forms of downhole information acquired by the oil industry. Old and new geothermal maps that are based on these measurements have invariably been drawn with an assumed constant or average ground surface temperature over the mapped areas. However, near ground-surface equilibrium temperature is a variable rather than a constant over any region; therefore, old and current geothermal gradient mapping methods give a false impression of the true thermal level of subsurface strata, and may lead to erroneous results of temperature-based calculations, such as the TTI. In this paper, a geothermal mapping methodmore » is presented in which extrapolated surface temperature is coupled with the corresponding geothermal gradient over the mapped area. The method was tested on areas in the Middle East and Africa. Results indicate that it is especially effective in delineating loci of vertical geothermal heat flux carried upwards by ascending subsurface fluids; such areas are preferential sites for hydrocarbon entrapment, especially in young sedimentary basins where migration is still in progress.« less

  6. Compilation of geothermal information: exploration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1978-01-01

    The Database for Geothermal Energy Exploration and Evaluation is a printout of selected references to publications covering the development of geothermal resources from the identification of an area to the production of elecric power. This annotated bibliography contains four sections: references, author index, author affiliation index, and descriptor index.

  7. Lake Pontchartrain Area/New Orleans (Louisiana) Meetings & Events

    EPA Pesticide Factsheets

    Lake Pontchartrain Area/New Orleans (Louisiana) of the Urban Waters Federal Partnership (UWFP) reconnects urban communities with their waterways by improving coordination among federal agencies and collaborating with community-led efforts

  8. Increased atmospheric deposition of mercury in reference lakes near major urban areas

    USGS Publications Warehouse

    Van Metre, P.C.

    2012-01-01

    Atmospheric deposition of Hg is the predominant pathway for Hg to reach sensitive ecosystems, but the importance of emissions on near-field deposition remains unclear. To better understand spatial variability in Hg deposition, mercury concentrations were analyzed in sediment cores from 12 lakes with undeveloped watersheds near to (<50 km) and remote from (>150 km) several major urban areas in the United States. Background and focusing corrected Hg fluxes and flux ratios (modern to background) in the near-urban lakes (68 ?? 6.9 ??g m -2 yr -1 and 9.8 ?? 4.8, respectively) greatly exceed those in the remote lakes (14 ?? 9.3 ??g m -2 yr -1 and 3.5 ?? 1.0) and the fluxes are strongly related to distance from the nearest major urban area (r 2 = 0.87) and to population and Hg emissions within 50-100 km of the lakes. Comparison to monitored wet deposition suggests that dry deposition is a major contributor of Hg to lakes near major urban areas. ?? 2011 Elsevier Ltd. All rights reserved.

  9. Sedimentary and Enhanced Geothermal Systems | Geothermal Technologies |

    Science.gov Websites

    NREL Sedimentary and Enhanced Geothermal Systems Sedimentary and Enhanced Geothermal Systems To innovative technologies, such as sedimentary and enhanced geothermal systems (EGS). Photo of a geothermal power plant in Imperial California. Capabilities To advance EGS and sedimentary geothermal systems, NREL

  10. Identification of hot spot area of sediment contamination in a lake system using texture characteristics.

    PubMed

    Sheela, A M; Letha, J; Joseph, Sabu; Thomas, Jobin

    2013-04-01

    Texture plays an important role in the identification of polluted stretch in a lake system. The organic matter as well as toxic elements get accumulated in the finer sediments. The aim of the work is to show the spatio-temporal distribution of texture of the lake sediment (Akkulam-Veli lake, Kerala) and to identify the hot spot areas of contamination. Hot spot areas vary with seasons. During PRM, (premonsoon), the upstream portion of the Akkulam lake is the hot spot. During MON (monsoon), the downstream portion of the Akkulam lake and the upstream portion of the Veli lake are the hot spots. During POM (postmonsoon), hot spot area is the downstream portion of the Akkulam lake. This methodology can be used for the quick identification of hot spots in water bodies.

  11. The Archaeology of Coralville Lake, Iowa. Volume 4. Recreation Area Survey. (Interim Report 2).

    DTIC Science & Technology

    1985-09-01

    THE ARCHAEOLOGY OF CORALVILLE LAKE, IOWA VOLUME IV: RECREATION AREA SURVEY (INTERIM REPORT II) p - [ JAN 1 4 1986 WAUWATOSA. WISCONSIN 86 1.13 117...THE ARCHAEOLOGY OF CORALVILLE LAKE, IOWA ; VOLUME IV: RECREATION AREA SURVEY (INTERIM REPORT II) Submitted To: Rock Island District Corps of Engineers...presents the results of intensive archaeological and geomorphic investigations at 14 special use or recreation areas at Coralville Lake, Iowa . The

  12. Effectiveness of terrestrial protected areas for conservation of lake fish communities.

    PubMed

    Chu, Cindy; Ellis, Lucy; de Kerckhove, Derrick T

    2018-06-01

    Freshwater protected areas are rare even though freshwater ecosystems are among the most imperiled in the world. Conservation actions within terrestrial protected areas (TPAs) such as development or resource extraction regulations may spill over to benefit freshwater ecosystems within their boundaries. Using data from 175 lakes across Ontario, Canada, we compared common indicators of fish-assemblage status (i.e., species richness, Shannon diversity index, catch per unit effort, and normalized-length size spectrum slopes) to evaluate whether TPAs benefit lake fish assemblages. Nearest neighbor cluster analysis was used to generate pairs of lakes: inside versus outside, inside versus bordering, and bordering versus outside TPAs based on lake characteristics. The diversity and abundance indicators did not differ significantly across comparisons, but normalized-length size spectrum slopes (NLSS) were significantly steeper in lakes outside parks. The latter indicated assemblage differences (greater abundances of small-bodied species) and less-efficient energy transfer through the trophic levels of assemblages outside parks. Although not significantly different, pollution- and turbidity-tolerant species were more abundant outside parks, whereas 3 of the 4 pollution-intolerant species were more abundant within parks. Twenty-one percent of the difference in slopes was related to higher total dissolved solids concentrations and angling pressure. Our results support the hypothesis that TPAs benefit lake fish assemblages and suggest that NLSS slopes are informative indicators for aquatic protected area evaluations because they represent compositional and functional aspects of communities. © 2017 Society for Conservation Biology.

  13. Multi-disciplinary study for the exploration of deep low enthalpy geothermal reservoirs, Neuchâtel, Switzerland

    NASA Astrophysics Data System (ADS)

    Mauri, G.; Abdelfettah, Y.; Negro, F.; Schill, E.; Vuataz, F.

    2011-12-01

    The authorities of the canton of Neuchâtel, in the Western part of Switzerland, are willing to develop geothermal energy for district heating in the two main cities of the canton: Neuchâtel, located along the Lake of Neuchâtel, and La Chaux-de-Fonds situated in a high valley of the Jura Massif. The geology of both areas is linked to the Jura Range and present complex structures, where the landscape is composed of anticlines associated with overthrust faults, which are overcut by strike-slip fault and secondary faulting events. The rock formations go from the Trias, which forms the detachment layer, up to the Quaternary rock. Bedrocks are mainly composed of limestones and marls, which can reach a thickness of several hundreds meters. The three main deep aquifers investigated in this area, from the shallowest (≤ 400 m below surface) to deepest (< 2000 m), are the Malm, the Dogger and the Muschelkalk. The estimated temperatures, based on previous studies, should range between 20 to 65 oC, which are function of depth, elevation and groundwater velocity. The expected low temperature is mainly due to the presence of karstic systems, which drains the heat towards the low elevation of the basin. The present study is based on gravimetry surveys, 3D geological models and 3D gravimetry models to best characterize the underground structures and to find areas where the rock properties would be favourable to geothermal exploitation. This means targets where permeability and porosity are high in the potential aquifers, allowing a significant flow at the future production wells. The results indicate that gravity anomalies are associated with both shallow and deep geological structures in the two exploration sites and that high resolution of dense grid gravity measurements combined with realistic 3D models of the geological structures allow to characterize interesting features for deep geothermal exploration. Gravity corrections were carried out with a computing code using

  14. Geothermal Energy: Evaluation of a Resource

    ERIC Educational Resources Information Center

    Bockemuehl, H. W.

    1976-01-01

    This article suggests the use of geothermal energy for producing electricity, using as an example the development at Wairakei, New Zealand. Other geothermal areas are identified, and economic and environmental co sts of additional development are explored. (Author/AV)

  15. Impacts of geothermal energy developments on hydrological environment in hot spring areas

    NASA Astrophysics Data System (ADS)

    Taniguchi, M.

    2015-12-01

    Water-energy nexus such as geothermal energy developments and its impacts on groundwater, river water, and coastal water is one of the key issues for the sustainable society. This is because the demand of both water and energy resources will be increasing in near future, and the tradeoff between both resources and conflict between stakeholders will be arisen. Geothermal power generation, hot springs heat power generation, and steam power generation, are developing in hot spring areas in Ring of Fire countries including Japan, as renewable and sustainable energy. Impacts of the wasted hot water after using hot springs heat and steam power generation on ecosystem in the rivers have been observed in Beppu, Oita prefecture, Japan. The number of the fish species with wasted hot water in the Hirata river is much less than that without wasted hot water in Hiyakawa river although the dominant species of tilapia was found in the Hirata river with wasted hot water. The water temperature in Hirata rive is increased by wasted hot water by 10 degree C. The impacts of the developments of steam power generations on hot spring water and groundwater in downstream are also evaluated in Beppu. The decreases in temperature and volume of the hot spring water and groundwater after the development are concerning. Stakeholder analysis related to hot spa and power generation business and others in Beppu showed common interests in community development among stakeholders and gaps in prerequisite knowledge and recognition of the geothermal resource in terms of economic/non-economic value and utilization as power generation/hot-spring. We screened stakeholders of four categories (hot spring resorts inhabitants, industries, supporters, environmentalists), and set up three communities consisting of 50 persons of the above categories. One remarkable result regarding the pros and cons of geothermal power in general terms was that the supporter count increased greatly while the neutralities count

  16. Study of structural change in volcanic and geothermal areas using seismic tomography

    NASA Astrophysics Data System (ADS)

    Mhana, Najwa; Foulger, Gillian; Julian, Bruce; peirce, Christine

    2014-05-01

    Long Valley caldera is a large silicic volcano. It has been in a state of volcanic and seismic unrest since 1978. Farther escalation of this unrest could pose a threat to the 5,000 residents and the tens of thousands of tourists who visit the area. We have studied the crustal structure beneath 28 km X 16 km area using seismic tomography. We performed tomographic inversions for the years 2009 and 2010 with a view to differencing it with the 1997 result to look for structural changes with time and whether repeat tomography is a capable of determining the changes in structure in volcanic and geothermal reservoirs. Thus, it might provide a useful tool to monitoring physical changes in volcanoes and exploited geothermal reservoirs. Up to 600 earthquakes, selected from the best-quality events, were used for the inversion. The inversions were performed using program simulps12 [Thurber, 1983]. Our initial results show that changes in both V p and V s were consistent with the migration of CO2 into the upper 2 km or so. Our ongoing work will also invert pairs of years simultaneously using a new program, tomo4d [Julian and Foulger, 2010]. This program inverts for the differences in structure between two epochs so it can provide a more reliable measure of structural change than simply differencing the results of individual years.

  17. Industrially induced changes in Earth structure at the geysers geothermal area, California

    USGS Publications Warehouse

    Foulger, G.R.; Grant, C.C.; Ross, A.; Julian, B.R.

    1997-01-01

    Industrial exploitation is causing clearly-measurable changes in Earth structure at The Geysers geothermal area, California. Production at The Geysers peaked in the late 1980s at ???3.5 ?? 103 kg s-1 of steam and 1800 MW of electricity. It subsequently decreased by about 10% per year [Barker et al., 1992] because of declining reservoir pressure. The steam reservoir coincides with a strong negative anomaly (???0.16, ???9%) in the compressional-to-shear seismic wave speed ratio vP/vS, consistent with the expected effects of low-pressure vapor-phase pore fluid [Julian et al., 1996]. Between 1991 and 1994 this anomaly increased in amplitude by up to about 0.07 (???4%). This is consistent with the expected effects of continued pressure reduction and conversion of pore water to steam as a result of exploitation. These unique results show that vP/vS tomography can easily detect saturation changes caused by exploitation of reservoirs, and is a potentially valuable technique for monitoring environmental change. They also provide geophysical observational evidence that geothermal energy is not a renewable energy source.

  18. Geophysical studies of the Crump Geyser known geothermal resource area, Oregon, in 1975

    USGS Publications Warehouse

    Plouff, Donald

    2006-01-01

    The U.S. Geological Survey (USGS) conducted geophysical studies in support of the resource appraisal of the Crump Geyser Known Geothermal Resource Area (KGRA). This area was designated as a KGRA by the USGS, and this designation became effective on December 24, 1970. The land classification standards for a KGRA were established by the Geothermal Steam Act of 1970 (Public Law 91-581). Federal lands so classified required competitive leasing for the development of geothermal resources. The author presented an administrative report of USGS geophysical studies entitled 'Geophysical background of the Crump Geyser area, Oregon, KGRA' to a USGS resource committee on June 17, 1975. This report, which essentially was a description of geophysical data and a preliminary interpretation without discussion of resource appraisal, is in Appendix 1. Reduction of sheets or plates in the original administrative report to page-size figures, which are listed and appended to the back of the text in Appendix 1, did not seem to significantly degrade legibility. Bold print in the text indicates where minor changes were made. A colored page-size index and tectonic map, which also show regional geology not shown in figure 2, was substituted for original figure 1. Detailed descriptions for the geologic units referenced in the text and shown on figures 1 and 2 were separately defined by Walker and Repenning (1965) and presumably were discussed in other reports to the committee. Heavy dashed lines on figures 1 and 2 indicate the approximate KGRA boundary. One of the principal results of the geophysical studies was to obtain a gravity map (Appendix 1, fig. 10; Plouff, and Conradi, 1975, pl. 9), which reflects the fault-bounded steepness of the west edge of sediments and locates the maximum thickness of valley sediments at about 10 kilometers south of Crump Geyser. Based on the indicated regional-gravity profile and density-contrast assumptions for the two-dimensional profile, the maximum

  19. Geothermal Energy Retrofit

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bachman, Gary

    The Cleary University Geothermal Energy Retrofit project involved: 1. A thermal conductivity test; 2. Assessment of alternative horizontal and vertical ground heat exchanger options; 3. System design; 4. Asphalt was stripped from adjacent parking areas and a vertical geothermal ground heat exchanger system installed; 5. the ground heat exchanger was connected to building; 6. a system including 18 heat pumps, control systems, a manifold and pumps, piping for fluid transfer and ductwork for conditioned air were installed throughout the building.

  20. Substrate conditions and abundance of lake trout eggs in a traditional spawning area in southeastern Lake Michigan

    USGS Publications Warehouse

    Dorr, John A.; O'Connor, Daniel V.; Foster, Neal R.; Jude, David J.

    1981-01-01

    Spawning by planted lake trout (Salvelinus namaycush) was documented by sampling with a diver-assisted pump in a traditional spawning area in southeastern Lake Michigan near Saugatuck, Michigan in mid-November in 1978 and 1979. Bottom depths at the 11 locations sampled ranged from 3 to 12 m and substrate size from boulders to sand. Periphyton (Cladophora and associated biota) was several millimeters thick at most stations but sparse at the shallowest. The most eggs recovered from a single sample occurred at the shallowest depth (3 m). In both years, some of the small numbers of eggs collected (9 in 1978, 14 in 1979) were alive and fertilized. Laboratory incubation of viable eggs resulted in successful hatching of larvae. When compared with egg densities measured at spawning sites used by self-sustaining populations of lake trout in other lakes, densities in the study are (0-13/m2) appeared to be critically low. Insufficient numbers of eggs, combined with harsh incubation conditions (turbulence, ice scour, sedimentation), were implicated as prime causes for lake trout reproductive failure in the study area, although other factors, such as inappropriate spawning behavior (selection of suboptimal spawning location, depth, or substrate) also may have reduced survival of eggs and larvae.

  1. Role of the Lakes in Groundwater Recharge and Discharge in the Young Glacial Area, Northern Poland.

    PubMed

    Jaworska-Szulc, Beata

    2016-07-01

    The aim of this research was to delineate characteristic hydrogeological lake types in the Young Glacial Area (YGA). The YGA is in the central and east part of the Kashubian Lake District (KLD) in Northern Poland, an area covered by deposits of Quaternary glaciation. All the bigger lakes were investigated in the area of about 1500 km(2) (39 lakes). The role of lakes in groundwater recharge and discharge was determined from total dissolved solids (TDS) in lake waters and also from groundwater flow simulation. The general trend was that gaining lakes, as determined by flow modeling, had higher values of TDS than losing lakes. In addition to typical gaining lakes (with TDS > 250 mg/l), there were losing lakes perched on glacial till deposits with very low TDS (<100 mg/l). Two groups of losing lakes were delineated: ones with very low TDS and another group with slightly higher TDS (due to local contact with groundwater). Flow-through lakes with TDS of 170-200 mg/l were also delineated. © 2015, National Ground Water Association.

  2. Hydrogeology, hydrologic budget, and water chemistry of the Medina Lake area, Texas

    USGS Publications Warehouse

    Lambert, Rebecca B.; Grimm, Kenneth C.; Lee, Roger W.

    2000-01-01

    A three-phase study of the Medina Lake area in Texas was done to assess the hydrogeology and hydrology of Medina and Diversion Lakes combined (the lake system) and to determine what fraction of seepage losses from the lake system might enter the regional ground-water-flow system of the Edwards and (or) Trinity aquifers. Phase 1 consisted of revising the geologic framework for the Medina Lake area. Results of field mapping show that the upper member of the Glen Rose Limestone underlies Medina Lake and the intervening stream channel from the outflow of Medina Lake to the midpoint of Diversion Lake, where the Diversion Lake fault intersects Diversion Lake. A thin sequence of strata consisting primarily of the basal nodular and dolomitic members of the Kainer Formation of the Edwards Group, is present in the southern part of the study area. On the southern side of Medina Lake, the contact between the upper member of the Glen Rose Limestone and the basal nodular member is approximately 1,000 feet above mean sea level, and the contact between the basal nodular member and the dolomitic member is approximately 1,050 feet above mean sea level. The most porous and permeable part of the basal nodular member is about 1,045 feet above mean sea level. At these altitudes, Medina Lake is in hydrologic connection with rocks in the Edwards aquifer recharge zone, and Medina Lake appears to lose more water to the ground-water system along this bedding plane contact. Hydrologic budgets calculated during phase 2 for Medina Lake, Diversion Lake, and Medina/Diversion Lakes combined indicate that: (1) losses from Medina and Diversion Lakes can be quantified; (2) a portion of those losses are entering the Edwards aquifer; and (3) losses to the Trinity aquifer in the Medina Lake area are minimal and within the error of the hydrologic budgets. Hydrologic budgets based on streamflow, precipitation, evaporation, and change in lake storage were used to quantify losses (recharge) to the ground

  3. Measuring ground movement in geothermal areas of Imperial Valley, California

    NASA Technical Reports Server (NTRS)

    Lofgren, B. E.

    1974-01-01

    Significant ground movement may accompany the extraction of large quantities of fluids from the subsurface. In Imperial Valley, California, one of the potential hazards of geothermal development is the threat of both subsidence and horizontal movement of the land surface. Regional and local survey nets are being monitored to detect and measure possible ground movement caused by future geothermal developments. Precise measurement of surface and subsurface changes will be required to differentiate man-induced changes from natural processes in this tectonically active region.

  4. Data integration and conceptual modelling of the Larderello geothermal area, Italy

    NASA Astrophysics Data System (ADS)

    Manzella, Adele; Gola, Gianluca; Bertini, Giovanni; Bonini, Marco; Botteghi, Serena; Brogi, Andrea; De Franco, Roberto; Dini, Andrea; Donato, Assunta; Gianelli, Giovanni; Liotta, Domenico; Montanari, Domenico; Montegrossi, Giordano; Petracchini, Lorenzo; Ruggieri, Giovanni; Santilano, Alessandro; Scrocca, Davide; Trumpy, Eugenio

    2017-04-01

    The Larderello geothermal field, located in southern Tuscany (Italy), is one of the most important long-living hydrothermal system in the world. The inner zone of the Northern Apennines is characterized by high heat flow, well constrained by several hundred measurements deriving from both shallow boreholes and deep exploration wells. It is widely accepted that the interplay among extensional tectonics, thinning of the previously overthickened crust and lithosphere, and magmatism related to crustal melting and hybridism, controlled the NW-SE trending geothermal anomaly occurring in southern Tuscany. At Larderello, the geothermal exploitation started at the beginning of the last century from the shallow evaporite-carbonate reservoir (about 700 - 1000 m b.g.l. on average) hosting a super-heated steam with temperature ranging from 150°C to 260°C. A deep exploration program was carried out in the early 1980s. Deep boreholes found a super-heated steam-dominated system hosted in the metamorphic basement (about 2500 - 4000 m b.g.l), characterized by temperatures ranging from 300°C to 350°C. In the SW part of the Larderello area (Lago locality), a temperature exceeding 400°C was measured down to 3000 m b.s.l. The 2D and 3D seismic exploration activities provided evidences of a seismic marker, locally showing bright spot features, defining the top of a deeper reflective crustal interval, named as "K-horizon". The K-horizon has not yet been drilled, but some boreholes approached it. This seismic reflector exhibits interesting positive correlation with the maximum peak of the hypocentre distribution of low-magnitude earthquakes and, at the same time, its shape coincides with the thermal anomaly distribution, in plain view. The review and updating of the velocity and resistivity models suggest the existence of over-pressurized fluids, likely of magmatic and/or thermo-metamorphic origin, which originate the seismic velocity anomalies. The upward migration and storage of the

  5. Geothermal studies in China

    NASA Astrophysics Data System (ADS)

    Ji-Yang, Wang; Mo-Xiang, Chen; Ji-An, Wang; Xiao, Deng; Jun, Wang; Hsien-Chieh, Shen; Liang-Ping, Hsiung; Shu-Zhen, Yan; Zhi-Cheng, Fan; Xiu-Wen, Liu; Ge-Shan, Huang; Wen-Ren, Zhang; Hai-Hui, Shao; Rong-Yan, Zhang

    1981-01-01

    Geothermal studies have been conducted in China continuously since the end of the 1950's with renewed activity since 1970. Three areas of research are defined: (1) fundamental theoretical research on geothermics, including subsurface temperatures, terrestrial heat flow and geothermal modeling; (2) exploration for geothermal resources and exploitation of geothermal energy; and (3) geothermal studies in mines. Regional geothermal studies have been conducted recently in North China and more than 2000 values of subsurface temperature have been obtained. Temperatures at a depth of 300 m generally range from 20 to 25°C with geothermal gradients from 20 to 40°C/km. These values are regarded as an average for the region with anomalies related to geological factors. To date, 22 reliable heat flow data from 17 sites have been obtained in North China and the data have been categorized according to fault block tectonics. The average heat flow value at 16 sites in the north is 1.3 HFU, varying from 0.7 to 1.8 HFU. It is apparent that the North China fault block is characterized by a relatively high heat flow with wide variations in magnitude compared to the mean value for similar tectonic units in other parts of the world. It is suggested that although the North China fault block can be traced back to the Archaean, the tectonic activity has been strengthening since the Mesozoic resulting in so-called "reactivation of platform" with large-scale faulting and magmatism. Geothermal resources in China are extensive; more than 2000 hot springs have been found and there are other manifestations including geysers, hydrothermal explosions, hydrothermal steam, fumaroles, high-temperature fountains, boiling springs, pools of boiling mud, etc. In addition, there are many Meso-Cenozoic sedimentary basins with widespread aquifers containing geothermal water resources in abundance. The extensive exploration and exploitation of these geothermal resources began early in the 1970's. Since then

  6. Evolution of salt and hydrocarbon migration: Sweet Lake area, Cameron Parish, Louisiana

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Spencer, J.A.; Sharpe, C.L.

    The interpretation of seismic, gravity, and well data in northern Cameron Parish, Louisiana suggest that lateral salt flow has influenced the area`s structural evolution, depositional patterns, and hydrocarbon migration. Sweet Lake Field has produced over 46 MMBO and 15 BCFG from Middle Miocene deltaic sands. The structural closure is a downthrown anticline on a fault controlled by the underlying salt feature. Sweet Lake Field overlies an allochthonous salt mass that was probably once part of an ancestral salt ridge extending from Hackberry to Big Lake fields. Nine wells encountering top of salt and several seismic lines define a detached saltmore » feature underlying over twenty square miles at depths from 8500-18,000 ft. Salt withdrawal in the East Hackberry-Big Lake area influenced the depositional patterns of the Oligocene lower Hackberry channel systems. Progradation of thick Middle Oligocene Camerina (A) and Miogypsinoides sands into the area caused salt thinning and withdrawal resulting in the development and orientation of the large Marginulina-Miogypsinoides growth fault northwest of Sweet Lake. Additional evidence for the southeast trend of the salt is a well approximately two miles southeast of Sweet Lake which encountered salt at approximately 19,800 ft. High quality 2-D and 3-D seismic data will continue to enhance the regional understanding of the evolving salt structures in the onshore Gulf Coast and the local understanding of hydrocarbon migration. Additional examples of lateral salt flow will be recognized and some may prove to have subsalt hydrocarbon potential.« less

  7. Slip and Dilation Tendency Analysis of the Salt Wells Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes

  8. Remote Sensing as a First Step in Geothermal Exploration in the Xilingol Volcanic Field in NE China

    NASA Astrophysics Data System (ADS)

    Peng, F.; Huang, S.; Xiong, Y.

    2013-12-01

    used to further enable a better visual geologic interpretation with the Landsat imagery of Xilingol. Several major volcanism controlling faults and Cenozoic volcanic eruption centers have been recognized from the linear and circular structures in the remote sensing images. The result shows that the major faults in the study area are mainly NEE oriented. Hidden faults and deep structures are inferred from the analysis of distribution regularities of linear and circular structures. Especially, the swarms of craters northwest to the Dalinuoer Lake appear to be controlled by some NEE trending hidden basement fractures. The intersecting areas of the NEE linear structures with NW trending structures overlapped by the circular structures are the favorable regions for geothermal resources. Seven areas have been preliminarily identified as the targets for further prospecting geothermal energy based on the visual interpretation of the geological structures. The study shows that RS and GIS have great application potential in the geothermal exploration in volcanic areas and will promote the exploration of renewable energy resources of great potential.

  9. Pueblo of Jemez Geothermal Feasibility Study Fianl Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    S.A. Kelley; N. Rogers; S. Sandberg

    2005-03-31

    This project assessed the feasibility of developing geothermal energy on the Pueblo of Jemez, with particular attention to the Red Rocks area. Geologic mapping of the Red Rocks area was done at a scale of 1:6000 and geophysical surveys identified a potential drilling target at a depth of 420 feet. The most feasible business identified to use geothermal energy on the reservation was a greenhouse growing culinary and medicinal herbs. Space heating and a spa were identified as two other likely uses of geothermal energy at Jemez Pueblo. Further geophysical surveys are needed to identify the depth to the Maderamore » Limestone, the most likely host for a major geothermal reservoir.« less

  10. Current threats to the Lake Texcoco globally important bird area

    Treesearch

    Jose L. Alcantara; Patricia Escalante Pliego

    2005-01-01

    Lake Texcoco was reported as almost dry in the late 1960s, and as a consequence the aquatic life has been considered gone since then. However, the government undertook a reclamation/restoration project in the area beginning in 1971 to help alleviate some of the environmental problems of Mexico City. Although Lake Texcoco was not completely dry in that period, the basin...

  11. Geothermal segmentation of the Cascade Range in the USA

    USGS Publications Warehouse

    Guffanti, Marianne; Muffler, L.J.; Mariner, R.H.; Sherrod, D.R.; Smith, James G.; Blackwell, D.D.; Weaver, C.S.

    1990-01-01

    Characteristics of the crustal thermal regime of the Quaternary Cascades vary systematically along the range. Spatially congruent changes in volcanic vent distribution, volcanic extrusion rate, hydrothermal discharge rate, and regional conductive heat flow define 5 geothermal segments. These segments are, from north to south: (1) the Washington Cascades north of Mount Rainier, (2) the Cascades from Mount Rainier to Mount Hood, (3) the Oregon Cascades from south of Mount Hood to the California border, (4) northernmost California, including Mount Shasta and Medicine Lake volcano, and (5) the Lassen region of northern California. This segmentation indicates that geothermal resource potential is not uniform in the Cascade Range. Potential varies from high in parts of Oregon to low in Washington north of Mount Rainier.

  12. Development of Genetic Occurrence Models for Geothermal Prospecting

    NASA Astrophysics Data System (ADS)

    Walker, J. D.; Sabin, A.; Unruh, J.; Monastero, F. C.; Combs, J.

    2007-12-01

    Exploration for utility-grade geothermal resources has mostly relied on identifying obvious surface manifestations of possible geothermal activity, e.g., locating and working near steaming ground or hot springs. This approach has lead to the development of over 130 resources worldwide, but geothermal exploration done in this manner is akin to locating hydrocarbon plays by searching for oil seeps. Confining exploration to areas with such features will clearly not discover a blind resource, that is, one that does not have surface expression. Blind resources, however, constitute the vast majority of hydrocarbon plays; this may be the case for geothermal resources as well. We propose a geothermal exploration strategy for finding blind systems that is based on an understanding of the geologic processes that transfer heat from the mantle to the upper crust and foster the conditions for hydrothermal circulation or enhanced geothermal exploration. The strategy employs a genetically based screening protocol to assess potential geothermal sites. The approach starts at the plate boundary scale and progressively focuses in on the scale of a producing electrical-grade field. Any active margin or hot spot is a potential location for geothermal resources. Although Quaternary igneous activity provides a clear indication of active advection of hot material into the upper crust, it is not sufficient to guarantee a potential utility-grade resource. Active faulting and/or evidence of high strain rates appear to be the critical features associated with areas of utility-grade geothermal potential. This is because deformation on its own can advect sufficient heat into the upper crust to create conditions favorable for geothermal exploitation. In addition, active deformation is required to demonstrate that open pathways for circulation of geothermal fluids are present and/or can be maintained. The last step in the screening protocol is to identify any evidence of geothermal activity

  13. Hydrologic relations between lakes and aquifer in a recharge area near Orlando, Florida

    USGS Publications Warehouse

    Lichtler, William F.; Hughes, G.H.; Pfischner, F.L.

    1976-01-01

    The three lakes investigated in Orange County, Florida, gain water from adjoining water-table aquifer and lose water to Floridan aquifer by downward leakage. Net seepage (net exchange of water between lake and aquifers) can be estimated by equation S = AX + BY, where S is net seepage, X represents hydraulic gradient between lake and water-table aquifer, A is lumped parameter representing effect of hydraulic conductivity and cross-sectional area of materials in flow section of water-table aquifer, Y is head difference between lake level and potentiometric surface of Floridan aquifer, and B is lumped parameter representing effect of hydraulic conductivity, area, and thickness of materials between lake bottom and Floridan aquifer. If values of S, X, and Y are available for two contrasting water-level conditions, coefficients A and B are determinable by solution of two simultaneous equations. If the relation between lake and ground-water level is the same on all sides of the lake--with regard to each aquifer--and if X and Y are truly representative of these relations, then X and Y terms of equation provide valid estimates of inflow to lake from water-table aquifer and outflow from lake to Floridan aquifer. (Woodard-USGS)

  14. Environmental analysis of geopressured-geothermal prospect areas, Brazoria and Kenedy Counties, Texas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    White, W.A.; McGraw, M.; Gustavson, T.C.

    Preliminary environmental data, including current land use, substrate lithology, soils, natural hazards, water resources, biological assemblages, meteorological data, and regulatory considerations have been collected and analyzed for approximately 150 km/sup 2/ of land: (1) near Chocolate Bayou, Brazoria County, Texas, where a geopressured-geothermal test well was drilled in 1978, and (2) near the rural community of Armstrong, Kenedy County, Texas, where future geopressured-geothermal test well development may occur. The study was designed to establish an environmental data base and to determine, within spatial constraints set by subsurface reservoir conditions, environmentally suitable sites for geopressured-geothermal wells.

  15. Geothermal Research | Geothermal Technologies | NREL

    Science.gov Websites

    . Impact Analysis Conducting analyses to determine the viability of geothermal energy production and Hybrid Systems Exploring the potential benefits of combining geothermal with other renewable energy Designing new models and studying new techniques to increase the production of geothermal energy.

  16. Geothermal development in the Philippines

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Elizagaque, R.F.; Tolentino, B.S.

    1982-06-01

    The development of geothermal resources and energy in the Philippines is discussed. Philippine National Oil Company-Energy Development Corporation initiated the first semi-commercial generation of geothermal power in July 1977 with the installation of a 3MWe plant. By 1980 the country had 440 MWe on line at Mak-Ban and Tiwi. This placed the Philippines second after the US among countries using geothermal energy for power generation. Before the end of 1981, PNOC-EDC added 6 additional MWe of geothermal power generating capacity to increase the total to 446 MWe. As part of the five-year National Energy Development Programme covering the period 1981-1985,more » additional power plants will be installed in various project areas to increase the share of geothermal power generation from the present 9.8% to 18.6% of the nationwide power-generation total, or the equivalent of 16.6 million barrels of oil per year. (MJF)« less

  17. 36 CFR 7.62 - Lake Chelan National Recreation Area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., and depending on local weather conditions, the superintendent may designate as open to the use of snowmobiles the following locations within the Lake Chelan National Recreation Area: (1) All open areas..., except cross-country ski trails and within the perimeter of the Buckner Orchard. Snowmobile use on open...

  18. Protection policy for Hawaii's native wildlife during geothermal energy development

    NASA Astrophysics Data System (ADS)

    Hannah, Lee

    1986-09-01

    Hawaii possesses abundant geothermal resources and rare native wildlife. Geothermal energy development has not posed a threat to native wildlife in the past, but development potential has recently reached a level at which concern for native wildlife is warranted. Potential geothermal resource areas in Hawaii intersect important native forest and endangered species habitat. The ability of existing laws to constrain development in these areas is in question. State and federal endangered species and environmental reporting laws have little ability to constrain geothermal development on private land. Hawaii's Land Use Law had been viewed by conservationists as protecting natural areas important to native wildlife, but recent decisions of the state Land Board sharply challenge this view. While this dispute was being resolved in the courts, the state legislature passed the Geothermal Subzone Act of 1983. Wildlife value was assessed in the geothermal subzone designation process mandated by this act, but the subzones designated primarily reflected inappropriate developer influence. All areas in which there was developer interest received subzone designation, and no area in which there was no developer interest was subzoned. This overriding emphasis on developer interest violated the intent of the sub-zone act, and trivialized the importance of other assessment criteria, among them native wildlife values.

  19. Absence of remote earthquake triggering within the Coso and Salton Sea geothermal production fields

    NASA Astrophysics Data System (ADS)

    Zhang, Qiong; Lin, Guoqing; Zhan, Zhongwen; Chen, Xiaowei; Qin, Yan; Wdowinski, Shimon

    2017-01-01

    Geothermal areas are long recognized to be susceptible to remote earthquake triggering, probably due to the high seismicity rates and presence of geothermal fluids. However, anthropogenic injection and extraction activity may alter the stress state and fluid flow within the geothermal fields. Here we examine the remote triggering phenomena in the Coso geothermal field and its surrounding areas to assess possible anthropogenic effects. We find that triggered earthquakes are absent within the geothermal field but occur in the surrounding areas. Similar observation is also found in the Salton Sea geothermal field. We hypothesize that continuous geothermal operation has eliminated any significant differential pore pressure between fractures inside the geothermal field through flushing geothermal precipitations and sediments out of clogged fractures. To test this hypothesis, we analyze the pore-pressure-driven earthquake swarms, and they are found to occur outside or on the periphery of the geothermal production field. Therefore, our results suggest that the geothermal operation has changed the subsurface fracture network, and differential pore pressure is the primary controlling factor of remote triggering in geothermal fields.

  20. Geophysical Analysis of Major Geothermal Anomalies in Romania

    NASA Astrophysics Data System (ADS)

    Panea, Ionelia; Mocanu, Victor

    2017-11-01

    The Romanian segment of the Eastern Pannonian Basin and the Moesian Platform are known for their geothermal and hydrocarbon-bearing structures. We used seismic, gravity, and geothermal data to analyze the geothermal behavior in the Oradea and Timisoara areas, from the Romanian segment of Eastern Pannonian Basin, and the Craiova-Bals-Optasi area, from the Moesian Platform. We processed 22 seismic reflection data sets recorded in the Oradea and Timisoara areas to obtain P-wave velocity distributions and time seismic sections. The P-wave velocity distributions correlate well with the structural trends observed along the seismic lines. We observed a good correlation between the high areas of crystalline basement seen on the time seismic sections and the high heat flow and gravity-anomaly values. For the Craiova-Bals-Optasi area, we computed a three-dimensional (3D) temperature model using calculated and measured temperature and geothermal gradient values in wells with an irregular distribution on the territory. The high temperatures from the Craiova-Bals-Optasi area correlate very well with the uplifted basement blocks seen on the time seismic sections and high gravity-anomaly values.

  1. Proceedings and findings of the geothermal commercialization workshop

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson, J.; Dhillon, H.

    The proceedings are presented of a Geothermal Commercialization Workshop conducted by the Division of Geothermal Resource Management, Department of Energy. The workshop was held in January-February 1979 at The MITRE Corporation facility in McLean, Virginia. The workshop addressed geothermal hydrothermal commercialization achievements and needs in the areas of Marketing and Outreach, Economics, Scenarios, and Progress Monitoring.

  2. Monitoring Geothermal Features in Yellowstone National Park with ATLAS Multispectral Imagery

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph; Berglund, Judith

    2000-01-01

    The National Park Service (NPS) must produce an Environmental Impact Statement for each proposed development in the vicinity of known geothermal resource areas (KGRAs) in Yellowstone National Park. In addition, the NPS monitors indicator KGRAs for environmental quality and is still in the process of mapping many geothermal areas. The NPS currently maps geothermal features with field survey techniques. High resolution aerial multispectral remote sensing in the visible, NIR, SWIR, and thermal spectral regions could enable YNP geothermal features to be mapped more quickly and in greater detail In response, Yellowstone Ecosystems Studies, in partnership with NASA's Commercial Remote Sensing Program, is conducting a study on the use of Airborne Terrestrial Applications Sensor (ATLAS) multispectral data for monitoring geothermal features in the Upper Geyser Basin. ATLAS data were acquired at 2.5 meter resolution on August 17, 2000. These data were processed into land cover classifications and relative temperature maps. For sufficiently large features, the ATLAS data can map geothermal areas in terms of geyser pools and hot springs, plus multiple categories of geothermal runoff that are apparently indicative of temperature gradients and microbial matting communities. In addition, the ATLAS maps clearly identify geyserite areas. The thermal bands contributed to classification success and to the computation of relative temperature. With masking techniques, one can assess the influence of geothermal features on the Firehole River. Preliminary results appear to confirm ATLAS data utility for mapping and monitoring geothermal features. Future work will include classification refinement and additional validation.

  3. Industrially induced changes in Earth structure at the Geysers Geothermal Area, California

    NASA Astrophysics Data System (ADS)

    Foulger, G. R.; Grant, C. C.; Ross, A.; Julian, B. R.

    Industrial exploitation is causing clearly-measurable changes in Earth structure at The Geysers geothermal area, California. Production at The Geysers peaked in the late 1980s at ˜3.5 × 10³ kg s-1 of steam and 1800 MW of electricity. It subsequently decreased by about 10% per year [Barker et al., 1992] because of declining reservoir pressure. The steam reservoir coincides with a strong negative anomaly (˜0.16, ˜9%) in the compressional-to-shear seismic wave speed ratio VP/ VS, consistent with the expected effects of low-pressure vapor-phase pore fluid [Julian et al., 1996]. Between 1991 and 1994 this anomaly increased in amplitude by up to about 0.07 (˜4%). This is consistent with the expected effects of continued pressure reduction and conversion of pore water to steam as a result of exploitation. These unique results show that VP/VS tomography can easily detect saturation changes caused by exploitation of reservoirs, and is a potentially valuable technique for monitoring environmental change. They also provide geophysical observational evidence that geothermal energy is not a renewable energy source.

  4. 36 CFR 7.57 - Lake Meredith National Recreation Area.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Lake Meredith National Recreation Area. 7.57 Section 7.57 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF.... (iv) PWC may not operate at greater than flat wake speed in the following designated areas: North...

  5. 36 CFR 7.57 - Lake Meredith National Recreation Area.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Lake Meredith National Recreation Area. 7.57 Section 7.57 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF.... (iv) PWC may not operate at greater than flat wake speed in the following designated areas: North...

  6. 36 CFR 7.57 - Lake Meredith National Recreation Area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Lake Meredith National Recreation Area. 7.57 Section 7.57 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF.... (iv) PWC may not operate at greater than flat wake speed in the following designated areas: North...

  7. 36 CFR 7.57 - Lake Meredith National Recreation Area.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Lake Meredith National Recreation Area. 7.57 Section 7.57 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF.... (iv) PWC may not operate at greater than flat wake speed in the following designated areas: North...

  8. 36 CFR 7.57 - Lake Meredith National Recreation Area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Lake Meredith National Recreation Area. 7.57 Section 7.57 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF.... (iv) PWC may not operate at greater than flat wake speed in the following designated areas: North...

  9. A time-lapse gravity survey of the Coso geothermal field, China Lake Naval Air Weapons Station, California

    USGS Publications Warehouse

    Phelps, Geoffrey; Cronkite-Ratcliff, Collin; Blake, Kelly

    2018-04-19

    We have conducted a gravity survey of the Coso geothermal field to continue the time-lapse gravity study of the area initiated in 1991. In this report, we outline a method of processing the gravity data that minimizes the random errors and instrument bias introduced into the data by the Scintrex CG-5 relative gravimeters that were used. After processing, the standard deviation of the data was estimated to be ±13 microGals. These data reveal that the negative gravity anomaly over the Coso geothermal field, centered on gravity station CER1, is continuing to increase in magnitude over time. Preliminary modeling indicates that water-table drawdown at the location of CER1 is between 65 and 326 meters over the last two decades. We note, however, that several assumptions on which the model results depend, such as constant elevation and free-water level over the study period, still require verification.

  10. Geothermal energy in Tibet

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lund, J.W.; McEuen, R.B.; Roberts, A.

    1984-09-01

    During the fall of 1983, a American delegation of 14 geothermal experts visited the People's Republic of China. The three-week trip included visits to Beijing (Peking), Chengdu, Lhasa, Yangbajing, and Kunming. By far the highlight of the trip was the journey to Tibet where the geothermal field and power station at Yangbajing were toured. Technical exchanges with Chinese and Tibetan geothermal scientists and engineers were made at Beijing, Lhasa, Yangbajing and Kunming. At Kunming in Yunnan Province, the geothermal field in the western part of the province was discussed, but not visited. This latter field is in the process ofmore » extensive investigation, but only minor direct-use development such as sulfur collection and wool washing is being undertaken. The drilling of wells and power plant construction is anticipated in the Rehai and Ridian fields in the near future. In general, Yunnan has one of the largest geothermal potentials in China with over 600 sites identified so far. The sites are widespread throughout the province, but the high temperature sites are located in the western part, a very mountainous area.« less

  11. Assessing Seasonal and Inter-Annual Variations of Lake Surface Areas in Mongolia during 2000-2011 Using Minimum Composite MODIS NDVI

    PubMed Central

    Kang, Sinkyu; Hong, Suk Young

    2016-01-01

    A minimum composite method was applied to produce a 15-day interval normalized difference vegetation index (NDVI) dataset from Moderate Resolution Imaging Spectroradiometer (MODIS) daily 250 m reflectance in the red and near-infrared bands. This dataset was applied to determine lake surface areas in Mongolia. A total of 73 lakes greater than 6.25 km2in area were selected, and 28 of these lakes were used to evaluate detection errors. The minimum composite NDVI showed a better detection performance on lake water pixels than did the official MODIS 16-day 250 m NDVI based on a maximum composite method. The overall lake area detection performance based on the 15-day minimum composite NDVI showed -2.5% error relative to the Landsat-derived lake area for the 28 evaluated lakes. The errors increased with increases in the perimeter-to-area ratio but decreased with lake size over 10 km2. The lake area decreased by -9.3% at an annual rate of -53.7 km2 yr-1 during 2000 to 2011 for the 73 lakes. However, considerable spatial variations, such as slight-to-moderate lake area reductions in semi-arid regions and rapid lake area reductions in arid regions, were also detected. This study demonstrated applicability of MODIS 250 m reflectance data for biweekly monitoring of lake area change and diagnosed considerable lake area reduction and its spatial variability in arid and semi-arid regions of Mongolia. Future studies are required for explaining reasons of lake area changes and their spatial variability. PMID:27007233

  12. Assessing Seasonal and Inter-Annual Variations of Lake Surface Areas in Mongolia during 2000-2011 Using Minimum Composite MODIS NDVI.

    PubMed

    Kang, Sinkyu; Hong, Suk Young

    2016-01-01

    A minimum composite method was applied to produce a 15-day interval normalized difference vegetation index (NDVI) dataset from Moderate Resolution Imaging Spectroradiometer (MODIS) daily 250 m reflectance in the red and near-infrared bands. This dataset was applied to determine lake surface areas in Mongolia. A total of 73 lakes greater than 6.25 km2in area were selected, and 28 of these lakes were used to evaluate detection errors. The minimum composite NDVI showed a better detection performance on lake water pixels than did the official MODIS 16-day 250 m NDVI based on a maximum composite method. The overall lake area detection performance based on the 15-day minimum composite NDVI showed -2.5% error relative to the Landsat-derived lake area for the 28 evaluated lakes. The errors increased with increases in the perimeter-to-area ratio but decreased with lake size over 10 km(2). The lake area decreased by -9.3% at an annual rate of -53.7 km(2) yr(-1) during 2000 to 2011 for the 73 lakes. However, considerable spatial variations, such as slight-to-moderate lake area reductions in semi-arid regions and rapid lake area reductions in arid regions, were also detected. This study demonstrated applicability of MODIS 250 m reflectance data for biweekly monitoring of lake area change and diagnosed considerable lake area reduction and its spatial variability in arid and semi-arid regions of Mongolia. Future studies are required for explaining reasons of lake area changes and their spatial variability.

  13. Retrofitting a Geothermal Plant with Solar and Storage to Increase Power Generation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhu, Guangdong; McTigue, Joshua Dominic P; Turchi, Craig S

    Solar hybridization using concentrating solar power (CSP) can be an effective approach to augment the power generation and power cycle efficiency of a geothermal power plant with a declining resource. Thermal storage can further increase the dispatchability of a geothermal/solar hybrid system, which is particularly valued for a national grid with high renewable penetration. In this paper, a hybrid plant design with thermal storage is proposed based on the requirements of the Coso geothermal field in China Lake, California. The objective is to increase the power production by 4 MWe. In this system, a portion of the injection brine ismore » recirculated through a heat exchanger with the solar heat transfer fluid, before being mixed with the production well brine. In the solar heating loop the brine should be heated to at least 155 degrees C to increase the net power. The solar field and storage were sized based on solar data for China Lake. Thermal storage is used to store excess power at the high-solar-irradiation hours and generate additional power during the evenings. The solar field size, the type and capacity of thermal storage and the operating temperatures are critical factors in determining the most economic hybrid system. Further investigations are required to optimize the hybrid system and evaluate its economic feasibility.« less

  14. Photo Gallery for Lake Pontchartrain Area/New Orleans (Louisiana)

    EPA Pesticide Factsheets

    Lake Pontchartrain Area/New Orleans (Louisiana) of the Urban Waters Federal Partnership (UWFP) reconnects urban communities with their waterways by improving coordination among federal agencies and collaborating with community-led efforts.

  15. Program Contacts for Lake Pontchartrain Area/New Orleans (Louisiana)

    EPA Pesticide Factsheets

    Lake Pontchartrain Area/New Orleans (Louisiana) of the Urban Waters Federal Partnership (UWFP) reconnects urban communities with their waterways by improving coordination among federal agencies and collaborating with community-led efforts

  16. Links Related to Lake Pontchartrain Area/New Orleans (Louisiana)

    EPA Pesticide Factsheets

    Lake Pontchartrain Area/New Orleans (Louisiana) of the Urban Waters Federal Partnership (UWFP) reconnects urban communities with their waterways by improving coordination among federal agencies and collaborating with community-led efforts

  17. Power-poor Philippines taps geothermal pool

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1982-04-15

    The current energy situation in the Philippines (75% imported oil) is reviewed and current and future activities in the area of geothermal energy use is discussed. It is estimated that by 1986, $830 million will be spent to develop the extensive geothermal sources to produce 13% of the nation's total energy. The high-quality geothermal sources are described as producing 162/sup 0/C water-steam mixture at a pressure of 6.68 kg/sec. Energy producing systems are described briefly as well as the environmental and equipment problems encountered already. The cost of geothermal energy is discussed (2.5 cents/kWh) and compared with energy costs ofmore » fossil-fuel and hydroelectricity. It is concluded that the geothermal energy sources should be a major contributor to the Philippines for at least 30 years. (MJJ)« less

  18. Determination of the contaminated area after the blowouts in Alasehir (Manisa/Turkey) Geothermal Area using geophysical methods

    NASA Astrophysics Data System (ADS)

    Timur, Emre

    2013-04-01

    Western Turkey is one of the most spectacular regions of widespread active continental extension in the world. The most prominent structures of this region are E-W trending Gediz and Büyük Menderes Grabens. Geothermal activity around city of Manisa in Gediz Graben has been investigated by many researchers and many drillings has been opened in order to produce electricity and heating purposes. In the middle of May, 2012, a geothermal blowout occurred 150 m away from the deep drilling, at the depth of 1100 m, in Alkan village of Alasehir resort in city of Manisa. After that, 5 big blowouts happened at the same area and hot water had been diverted to Alkan stream for almost 4 months. In this study, it was intended to determine contaminated area by using magnetic susceptibility measurements for the surface and VLF-R method for underground layers. Magnetic observations were carried out by using Bartington MS2E system and VLF-R by Scintrex ENVI-VLF. It is observed that magnetic susceptibility values vary between 90-160 cgs in the center of the blowout and 30-80 cgs 50 m around of it. All of the susceptibility values were mapped and contaminated areas was clearly defined on the surface using 246 data points. Besides, VLF-R studies were carried out along 21 profiles each of a length of 170 m at three different frequencies with a line and station spacing of 5 m. Laterally constrained two layer inversion was applied to each station and in addition to the inversion of all profiles for each frequency, all lines were stacked within a precise resistivity interval and 2-D maps of the contaminated zones were obtained.

  19. World Geothermal Congress WGC-2015

    NASA Astrophysics Data System (ADS)

    Tomarov, G. V.; Shipkov, A. A.

    2016-08-01

    This article discusses materials and results of the World Geothermal Congress that was held in Melbourne (Australia) from April 19 to April 25, 2015. Information on the extent and technological features of utilization of geothermal resources for heat supply and power production, as well as in other economic areas, is given. A stable growth in the capacity and number of geothermal power systems that is determined by ecological cleanliness, economic efficiency, and the highest (among renewable energy sources) indicators of installed capacity utilization is shown. It was noted that combined schemes of geothermal power plants (GPPs), such as turbine units of different type (binary units, units with one or two separation pressures, etc.), have become more frequently used to increase the efficiency of utilization of geothermal heat carrier. Actual data determining room heating systems with the total worldwide capacity of nearly 50000 MW thermal (MWt) as the most currently significant segment of consumption of geothermal waters are given. In addition, geothermal resources are also utilized in soil pumps, balneological and sports basins, greenhouse complexes, and other manufactures. It was noted that geological studies were carried out in more than 40 countries, with the development of methods of simulation of tanks for the existing and new geothermal fields. Trends of development and the role of geothermal power engineering in the energy supply of many countries are shown. It was shown that prospects for the development of geothermal power generation are significantly associated with utilization of low-temperature geothermal sources in binary power generating units, as well as with the increase in installed capacity of operating geothermal power plants (GPPs) without drilling additional wells, i.e., by using waste geothermal heat carrier in binary-cycle or combined-cycle power plants. The article provides data on a pilot binary power unit at Pauzhetka GPP and on a

  20. 36 CFR 7.55 - Lake Roosevelt National Recreation Area.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Lake Roosevelt National Recreation Area. 7.55 Section 7.55 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF... except in designated swimming areas. (4) PWC may not be operated at greater than flat-wake speeds in the...

  1. 36 CFR 7.55 - Lake Roosevelt National Recreation Area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Lake Roosevelt National Recreation Area. 7.55 Section 7.55 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF... except in designated swimming areas. (4) PWC may not be operated at greater than flat-wake speeds in the...

  2. 36 CFR 7.55 - Lake Roosevelt National Recreation Area.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Lake Roosevelt National Recreation Area. 7.55 Section 7.55 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF... except in designated swimming areas. (4) PWC may not be operated at greater than flat-wake speeds in the...

  3. 36 CFR 7.55 - Lake Roosevelt National Recreation Area.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Lake Roosevelt National Recreation Area. 7.55 Section 7.55 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF... except in designated swimming areas. (4) PWC may not be operated at greater than flat-wake speeds in the...

  4. 36 CFR 7.55 - Lake Roosevelt National Recreation Area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Lake Roosevelt National Recreation Area. 7.55 Section 7.55 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF... except in designated swimming areas. (4) PWC may not be operated at greater than flat-wake speeds in the...

  5. The missing link between submarine volcano and promising geothermal potential in Jinshan, Northern Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, S. C.; Hutchings, L.; Chang, C. C.; Lee, C. S.

    2017-12-01

    The Tatun volcanic group (TVG) and the Keelung submarine volcano (KSV) are active volcanoes and surrounding three nuclear plant sites in north Taiwan. The famous Jinshan-Wanli hot springs locates between TVG and KSV, moreover, the geochemical anomalies of acidic boiling springs on the seacoast infer that the origin is from magmatic fluids, sea water and meteoric water mixture, strongly implying that mantle fluids ascends into the shallow crust. The evidence for a magma chamber, submarine volcano, and boiling springs have a close spatial relationship. Based on UNECE specifications to Geothermal Energy Resources (2016), the Jinshan-Wanli geothermal area could be classified as Known Geothermal Energy Source for geothermal direct use and Potential Geothermal Energy Source for conventional geothermal system. High resolution reservoir exploration and modeling in Jinshan-Wanli geothermal area is developing for drilling risk mitigation. The geothermal team of National Taiwan Ocean University and local experts are cooperating for further exploration drilling and geothermal source evaluation. Keywords: geothermal resource evaluation, Jinshan-Wanli geothermal area, submarine volcano

  6. Quantifying the undiscovered geothermal resources of the United States

    USGS Publications Warehouse

    Williams, Colin F.; Reed, Marshall J.; DeAngelo, Jacob; Galanis, S. Peter

    2009-01-01

    National Park, are unique in North America and highly unlikely to have counterparts with equivalent characteristics among the systems comprising the undiscovered resources. (2) Historical geothermal exploration has been limited in both the effectiveness of techniques employed and spatial coverage, since most exploration has targeted areas associated with surface thermal manifestations in the most easily accessible lands. (3) As noted by other investigators, in general, the hottest and largest geothermal systems are those with heat sources arising from recent magmatic activity. Consequently, a larger fraction of the undiscovered resource is associated with those areas favorable to the formation of this type of geothermal system, including some relatively remote areas, such as the Aleutian volcanic arc in Alaska.

  7. Geothermal Monitoring in Yellowstone National Park

    NASA Astrophysics Data System (ADS)

    Heasler, H. P.; Jaworowski, C.; Susong, D. D.; Lowenstern, J. B.

    2007-12-01

    When the first exploring parties surveyed the Yellowstone region in the late 19th Century, it was the geologic wonders - geysers, hot springs, mudpots, fumaroles - that captured their imaginations. Because of these treasures, the U.S. Congress set aside and dedicated this land of "natural curiosities" as the world's first "public pleasuring ground". Protection of Yellowstone's unique geothermal features is a key mission of Yellowstone National Park as mandated by U. S. Congressional law. In response to that mandate, the Yellowstone National Park Geology Program developed a peer-reviewed, Geothermal Monitoring Plan in 2003. With partial Congressional funding of the Plan in 2005, implementation of a scientific monitoring effort began. Yellowstone's scientific geothermal monitoring effort includes the acquisition of time-temperature data using electronic data loggers, basic water quality data, chloride flux data, estimates of radiative heat flux using airborne, thermal infrared imagery, geothermal gas monitoring, and the monitoring of groundwater wells. Time- temperature data are acquired for geysers, hot springs, steam vents, wells, rivers, and the ground. Uses of the time-temperature data include public safety, calibrating airborne thermal infrared-imagery, monitoring selected thermal features for potential hydrothermal explosions, and determining the spatial and temporal changes in thermal areas. Since 2003, upgrades of Yellowstone's stream gaging network have improved the spatial and temporal precision of the chloride flux, water quality, and groundwater components of the Geothermal Monitoring Plan. All of these methods serve both for geothermal monitoring and volcano monitoring as part of the Yellowstone Volcano Observatory. A major component of the Geothermal Monitoring Plan is remote sensing of the Yellowstone volcano and its active hydrothermal areas at various scales. The National Center for Landscape Fire Analysis at the University of Montana and the USDA

  8. Glacial lakes in the Indian Himalayas--from an area-wide glacial lake inventory to on-site and modeling based risk assessment of critical glacial lakes.

    PubMed

    Worni, Raphael; Huggel, Christian; Stoffel, Markus

    2013-12-01

    Glacial lake hazards and glacial lake distributions are investigated in many glaciated regions of the world, but comparably little attention has been given to these topics in the Indian Himalayas. In this study we present a first area-wide glacial lake inventory, including a qualitative classification at 251 glacial lakes >0.01 km(2). Lakes were detected in the five states spanning the Indian Himalayas, and lake distribution pattern and lake characteristics were found to differ significantly between regions. Three glacial lakes, from different geographic and climatic regions within the Indian Himalayas were then selected for a detailed risk assessment. Lake outburst probability, potential outburst magnitudes and associated damage were evaluated on the basis of high-resolution satellite imagery, field assessments and through the use of a dynamic model. The glacial lakes analyzed in the states of Jammu and Kashmir and Himachal Pradesh were found to present moderate risks to downstream villages, whereas the lake in Sikkim severely threatens downstream locations. At the study site in Sikkim, a dam breach could trigger drainage of ca. 16×10(6)m(3) water and generate maximum lake discharge of nearly 7000 m(3) s(-). The identification of critical glacial lakes in the Indian Himalayas and the detailed risk assessments at three specific sites allow prioritizing further investigations and help in the definition of risk reduction actions. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Impacts of urban sprawl on the area of downtown lakes in a highly developing city on central China

    NASA Astrophysics Data System (ADS)

    Zhang, W.; Zhang, Y.

    2016-12-01

    Wuhan city in central China is full of water resources and numerous lakes are located. Downtown lakes have significant ecological value and ornamental value for urban inhabitants in Wuhan. Under the rapid process of urban sprawl, downtown lakes are occupied by impervious areas. This research uses Landsat images to extract land uses from 1991 to 2013 in Wuhan city , and attempts to find out how urban sprawl affects the water body area decline in space. Two largest downtown lakes in Wuhan city, Donghu Lake located in central city and Tangxunhu Lake located in suburbs, are taken as case study area. A direction change index (DCI) is proposed to evaluate the changes of a specific land use in different directions. The results reveal that two downtown lakes are undergoing rapid water body area decline from 1991 to 2013, with decline rate are -0.022 in Donghu watershed and -0.011 in Tangxunhu watershed. 68.26% and 62.50% of the reduced water body is occupied by built-up land in Donghu watershed and Tangxunhu watershed, respectively. According to DCI, the water body reduce is highly correlated with built-up land increase in all direction. Moreover, it is found that in the Donghu watershed the north-west part suffered significant water body area decline, which is close to central city. While in Tangxunhu watershed, the area of water body declined in north-west, south-west and north-east part, and the area obstructed from central city by the lake was suffering less water body area decline. It is concluded that the water body area of downtown lakes are highly affected by the process of urban sprawl, and the lakes in central districts trends to suffer higher descend than that of the downtown lake located in suburbs. Meanwhile, even for the same downtown lake, the area orientating and close to the central city may suffer more rapid decline than the area that does not orientate to the central city.

  10. Decadal and Seasonal Variations of Alpine Lakes in Glacierized areas of Central Asia during 1990-2015

    NASA Astrophysics Data System (ADS)

    Li, J.; Warner, T.; Chen, X.; Bao, A.

    2016-12-01

    Central Asia is one of the world's most vulnerable areas responding to global change. Glacier lakes in the alpine regions remain sensitive to climatic change and fluctuate with temperature and precipitation variations. Study shows that glaciers in Central Asia have retreated dramatically, leading to the expansion of the existing glacial lakes and the emergence of many new glacier lakes. The existence of these lakes increases the possibility of outburst flood during the ice melting season, which can bring a disaster to the downstream area. Mapping glacial lakes and monitoring their changes would improve our understanding of regional climate change and glacier-related hazards. Glacial lakes in Central Asia are mainly located at the Tianshan Mountains, the Altai Mountains, the Kunlun Mountains and the Pamirs with average elevation more than 1500 meters. Most of these lakes are supplied with the glaciers or snowmelt water during the summer seasons. Satellite remote sensing provides an efficient and objective tool to analyze the status and variations of glacial lakes. The increased availability of remote sensing sensors with appropriate spatial and temporal resolutions, broad coverage makes lake investigations more feasible and cost-effective. The paper intends to map glacier lake changes in glacierized alpine mountains with Landsat TM/ETM+ imagery. More than 600 scenes of Landsat images in circa 1990, circa 2000, circa 2010 and circa 2015 are used to map the decadal glacial lake changes over the Central Asia, and about 8 expanding glacial lakes are selected to map seasonal changes. Over 12000 glacial lakes were mapped in circa 1990, and in 2015, lake number are more than 16000, most of these new lakes are emerging in the last 10 years. The result shows that the number and area of the glacial lakes in the Altain Mountain remain stable, while the Tianshan Mountain have experienced expanding changes in the last two decades, and about a half number of lake areas are

  11. Integrating limnological characteristics of high mountain lakes into the landscape of a natural area

    USGS Publications Warehouse

    Larson, Gary L.; Wones, A.; McIntire, C.D.; Samora, B.

    1994-01-01

    A general conceptual watershed-lake model of the complex interactions among climatic conditions, watershed location and characteristics, lake morphology, and fish predation was used to evaluate limnological characteristics of high mountain lakes. Our main hypothesis was that decreasing elevation in mountainous terrain corresponds to an increase in diversity of watershed size and lake area, depth, temperature, nutrient concentrations, and productivity. A second hypothesis was that watershed location and aspect relative to climatic gradients within mountainous terrain influences the limnological characteristics of the lakes. We evaluated these hypotheses by examining watershed location, aspect and size; lake morphology; water quality; and phytoplankton and zooplankton community characteristics among high mountain forest and subalpine lakes in Mount Rainier National Park. Although many of the comparisons between all forest and subalpine lakes were statistically insignificant, the results revealed trends that were consistent with our hypotheses. The forest lake group included more lakes with larger watersheds, larger surface areas, greater depths, higher concentrations of nutrients, and higher algal biovolumes than did the group of subalpine lakes. Deep lakes, which were mostly of the forest lake type, exhibited thermal stratification and relatively high values of some of the water-quality variables near the lake bottoms. However, the highest near-surface water temperatures and phytoplankton densities and the taxonomic structures of the phytoplankton and zooplankton assemblages were more closely related to geographical location, which corresponded to a west-east climate gradient in the park, than to lake type. Some crustacean and rotifer taxa, however, were limited in distribution by lake type. Fish predation did not appear to play an important role in the structure of the crustacean zooplankton communities at the genus level with the exception of Mowich Lake, where

  12. The flora of the Cottonwood Lake Study Area, Stutsman County, North Dakota

    USGS Publications Warehouse

    Mushet, D.M.; Euliss, N.H.; Lane, S.P.; Goldade, C.M.

    2004-01-01

    The 92 ha Cottonwood Lake Study Area is located in south-central North Dakota along the eastern edge of a glacial stagnation moraine known as the Missouri Coteau. The study area has been the focus of biologic and hydrologic research since the U.S. Fish and Wildlife Service purchased the site in 1963. We studied the plant communities of the Cottonwood Lake Study Area from 1992 to 2001. During this time period, the vascular flora of the study area consisted of 220 species representing 51 families. Over half of the species were perennial forbs (117 species). Perennial grasses (26 species) and annual forbs (22 species) made up the next two largest physiognomic groupings. The flora, having a mean Coefficient of Conservatism of 4.6 and a Floristic Quality Index of 62, consisted of 187 native species. Thirty-three species were non-natives. Our annotated list should provide information useful to researchers, graduate students, and others as they design and implement future studies in wetlands and uplands both in and around the Cottonwood Lake Study Area.

  13. Geothermal power development in Hawaii. Volume 1. Review and analysis

    NASA Astrophysics Data System (ADS)

    1982-06-01

    The history of geothermal exploration in Hawaii is reviewed briefly. The nature and occurrences of geothermal resources are presented island by island. An overview of geothermal markets is presented. Other topics covered are: potential markets of the identified geothermal areas, well drilling technology, hydrothermal fluid transport, overland and submarine electrical transmission, community aspects of geothermal development, legal and policy issues associated with mineral and land ownership, logistics and infrastructure, legislation and permitting, land use controls, Regulation 8, public utilities commission, political climate and environment, state plans, county plans, geothermal development risks, and business planning guidelines.

  14. Geothermal Energy.

    ERIC Educational Resources Information Center

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    An introduction to geothermal energy is provided in this discussion of: (1) how a geothermal reservoir works; (2) how to find geothermal energy; (3) where it is located; (4) electric power generation using geothermal energy; (5) use of geothermal energy as a direct source of heat; (6) geopressured reservoirs; (7) environmental effects; (8)…

  15. Geothermal Today: 2003 Geothermal Technologies Program Highlights (Revised)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    2004-05-01

    This outreach publication highlights milestones and accomplishments of the DOE Geothermal Technologies Program for 2003. Included in this publication are discussions of geothermal fundamentals, enhanced geothermal systems, direct-use applications, geothermal potential in Idaho, coating technology, energy conversion R&D, and the GeoPowering the West initiative.

  16. Changes in physical-thermal properties of soil related to very shallow geothermal systems in urban areas

    NASA Astrophysics Data System (ADS)

    Di Sipio, Eloisa; Psyk, Mario; Popp, Thomas; Bertermann, David

    2016-04-01

    In the near future the population living in urban areas is expected to increase. This worldwide trend will lead to a high concentrations of infrastructures in confined areas, whose impact on land use and shallow subsurface must be well evaluated. Since shallow geothermal energy resource is becoming increasingly important as renewable energy resource, due to its huge potential in providing thermal energy for residential and tertiary buildings and in contributing to reduce greenhouse gas emission, the number of installed geothermal systems is expected to continue to rise in the near future. However, a leading question concerns the short and long-term effect of an intensive thermal use of the shallow subsurface for heat generation, cooling and thermal energy storage. From an environmental and technical point of view, changes on ground temperatures can influence the physical-thermal properties of soil and groundwater as well as their chemical and biological features. In this study the preliminary results of ITER Project are presented. This project, funded by European Union, focuses on improving heat transfer efficiency of very shallow geothermal systems, as horizontal collector systems or special forms (i.e. helix system), interesting the first 2 m of depth from ground level. Given the heterogeneity of sedimentary deposits in alluvial plain and the uncertainties related to the estimation of thermal parameters for unconsolidated material affected by thermal use, physical-thermal parameters (i.e. moisture content, bulk density, thermal conductivity...) where determined in laboratory for sand, clay and loamy sand samples. In addition, preliminary results from a field test site located within an urban area will be also shown. The main aim is to improve our knowledge of heat transfer process in the soil body in order (i) to create a reference database to compare subsequently the impact of temperature variations on the same properties and (ii) to provide reliable data for

  17. Numerical modeling of crater lake seepage

    NASA Astrophysics Data System (ADS)

    Todesco, M.; Rouwet, D.

    2012-04-01

    The fate of crater lake waters seeping into the volcanic edifice is poorly constrained. Quantification of the seepage flux is important in volcanic surveillance as this water loss counterbalances the inflow of hot magmatic fluids into the lake, and enters the mass balance computation. Uncertainties associated with the estimate of seepage therefore transfer to the estimate of magmatic degassing and hazard assessment. Moreover, when the often acidic lake brines disperse into the volcanic edifice, they may lead to acid attack (stress corrosion) and eventually to mechanical weakening of the volcano flanks, thereby causing an indirect volcanic risk. Understanding of the features that control the underground propagation of lake waters and their interactions with the magmatic-hydrothermal system is therefore highly recommended in volcanic hazard assessment. In this work, we use the TOUGH2 geothermal simulator to investigate crater lake water seepage in different volcanic settings. Modeling is carried out to describe the evolution of a hydrothermal system open on a hot, pressurized reservoir of dry gas and capped by a volcanic lake. Numerical simulations investigate the role of lake morphology, system geometry, rock properties, and of the conditions applied to the lake and to the gas reservoir at depth.

  18. Slip and Dilation Tendency Analysis of the Tuscarora Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes

  19. Changes in the area of inland lakes in arid regions of central Asia during the past 30 years.

    PubMed

    Bai, Jie; Chen, Xi; Li, Junli; Yang, Liao; Fang, Hui

    2011-07-01

    Inland lakes are major surface water resource in arid regions of Central Asia. The area changes in these lakes have been proved to be the results of regional climate changes and recent human activities. This study aimed at investigating the area variations of the nine major lakes in Central Asia over the last 30 years. Firstly, multi-temporal Landsat imagery in 1975, 1990, 1999, and 2007 were used to delineate lake extents automatically based on Normalized Difference Water Index (NDWI) threshold segmentation, then lake area variations were detailed in three decades and the mechanism of these changes was analyzed with meteorological data and hydrological data. The results indicated that the total surface areas of these nine lakes had decreased from 91,402.06 km(2) to 46,049.23 km(2) during 1975-2007, accounting for 49.62% of their original area of 1975. Tail-end lakes in flat areas had shrunk dramatically as they were induced by both climate changes and human impacts, while alpine lakes remained relatively stable due to the small precipitation variations. With different water usage of river outlets, the variations of open lakes were more flexible than those of other two types. According to comprehensive analyses, different types of inland lakes presented different trends of area changes under the background of global warming effects in Central Asia, which showed that the increased human activities had broken the balance of water cycles in this region.

  20. Using Facilities And Potential Of Geothermal Resources In The Canakkale Province - NW Turkey

    NASA Astrophysics Data System (ADS)

    Deniz, Ozan; Acar Deniz, Zahide

    2016-04-01

    Turkey, due to its geological location, has a rich potential in point of geothermal resources. Çanakkale province is located northwestern (NW) part of Turkey and it has important geothermal fields in terms of geothermal energy potential. Geothermal resources reach to the surface both effects of past volcanic activity and extensions of fault zones associated with complex tectonic systems in the region. The aim of this study is to summarize hydrogeochemical characteristics, using facilities and potential of hot springs and spas located in the Çanakkale province. There are 13 geothermal fields in the region and the surface temperatures of hot springs are ranging between 28 centigrade degree and 175 centigrade degree. Hydrogeochemical compositions of thermal water display variable chemical compositions. Na, Ca, SO4, HCO3 and Cl are the dominant ions in these waters. Thermal waters of Tuzla and Kestanbol geothermal fields which is located the near coastal area can be noted NaCl type. Because these two geothermal waters have high TDS values, scaling problems are seen around the hot springs and pipelines. Geothermal waters in the province are meteoric origin according to oxygen-18, deuterium and tritium isotopes data. Long underground residence times of these waters and its temperatures have caused both more water - rock interaction and low tritium values. Geothermal energy is utilized in many areas in Turkey today. It is generally used for space heating, balneotherapy and electricity generation. Explorations of geothermal resources and investments in geothermal energy sector have risen rapidly in the recent years particularly in western Turkey. High-temperature geothermal fields are generally located in this region related to the Aegean Graben System and the North Anotalian Fault Zone. All geothermal power plants in Turkey are located in this region. Considering the Çanakkale province, most geothermal fields are suitable for multipurpose usage but many of them have

  1. 3D Model of the Tuscarora Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    The Tuscarora geothermal system sits within a ~15 km wide left-step in a major west-dipping range-bounding normal fault system. The step over is defined by the Independence Mountains fault zone and the Bull Runs Mountains fault zone which overlap along strike. Strain is transferred between these major fault segments via and array of northerly striking normal faults with offsets of 10s to 100s of meters and strike lengths of less than 5 km. These faults within the step over are one to two orders of magnitude smaller than the range-bounding fault zones between which they reside. Faults within the broad step define an anticlinal accommodation zone wherein east-dipping faults mainly occupy western half of the accommodation zone and west-dipping faults lie in the eastern half of the accommodation zone. The 3D model of Tuscarora encompasses 70 small-offset normal faults that define the accommodation zone and a portion of the Independence Mountains fault zone, which dips beneath the geothermal field. The geothermal system resides in the axial part of the accommodation, straddling the two fault dip domains. The Tuscarora 3D geologic model consists of 10 stratigraphic units. Unconsolidated Quaternary alluvium has eroded down into bedrock units, the youngest and stratigraphically highest bedrock units are middle Miocene rhyolite and dacite flows regionally correlated with the Jarbidge Rhyolite and modeled with uniform cumulative thickness of ~350 m. Underlying these lava flows are Eocene volcanic rocks of the Big Cottonwood Canyon caldera. These units are modeled as intracaldera deposits, including domes, flows, and thick ash deposits that change in thickness and locally pinch out. The Paleozoic basement of consists metasedimenary and metavolcanic rocks, dominated by argillite, siltstone, limestone, quartzite, and metabasalt of the Schoonover and Snow Canyon Formations. Paleozoic formations are lumped in a single basement unit in the model. Fault blocks in the eastern

  2. Monitoring the lake area changes of the Qinghai-Tibet Plateau using coarse-resolution time series remote sensing data

    NASA Astrophysics Data System (ADS)

    Ma, M.

    2015-12-01

    The Qinghai-Tibet Plateau (QTP) is the world's highest and largest plateau and is occasionally referred to as "the roof of the world". As the important "water tower", there are 1,091 lakes of more than 1.0 km2 in the QTP areas, which account for 49.4% of the total area of lakes in China. Some studies focus on the lake area changes of the QTP areas, which mainly use the middle-resolution remote sensing data (e.g. Landsat TM). In this study, the coarse-resolution time series remote sensing data, MODIS data at a spatial resolution of 250m, was used to monitor the lake area changes of the QTP areas during the last 15 years. The dataset is the MOD13Q1 and the Normal Difference Vegetation Index (NDVI) is used to identify the lake area when the NDVI is less than 0. The results show the obvious inner-annual changes of most of the lakes. Therefore the annually average and maximum lake areas are calculated based on the time series remote data, which can better quantify the change characteristics than the single scene of image data from the middle-resolution data. The results indicate that there are big spatial variances of the lake area changes in the QTB. The natural driving factors are analyzed for revealing the causes of changes.

  3. Influences of climate change on area variation of Qinghai Lake on Qinghai-Tibetan Plateau since 1980s.

    PubMed

    Tang, Lingyi; Duan, Xiaofang; Kong, Fanjin; Zhang, Fan; Zheng, Yangfan; Li, Zhen; Mei, Yi; Zhao, Yanwen; Hu, Shuijin

    2018-05-09

    Qinghai-Tibetan Plateau is the most sensitive region to global warming on Earth. Qinghai Lake, the largest lake on the plateau, has experienced evident area variation during the past several decades. To quantify the area changes of Qinghai Lake, a satellite-based survey based on Landsat images from the 1980s to 2010s has been performed. In addition, meteorological data from all the seven available stations on Qinghai-Tibetan Plateau has been analyzed. Area of Qinghai Lake shrank ~2% during 1987-2005, and then increased ~3% from 2005-2016. Meanwhile, the average annual temperature increased 0.319 °C/10 y in the past 50 years, where the value is 0.415 °C/10 y from 2005-2016. The structural equation modeling (SEM) shows that precipitation is the primary factor influencing the area of Qinghai Lake. Moreover, temperature might be tightly correlated with precipitation, snow line, and evaporation, thereby indirectly causes alternations of the lake area. This study elucidated the significant area variation of water body on the Qinghai-Tibetan Plateau under global warming since 1980s.

  4. Montana geothermal commercialization planning. Semi-annual progress report, January 1, 1979-June 30, 1979

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Birkby, J.; Brown, K.; Chapman, M.

    1979-06-01

    Area development plans were prepared which describe geothermal resources and their potential use on a county or multicounty basis. Development plans for two areas are presented. Cost analyses show that the proximity of the geothermal resource to the end user is the most important criterion in geothermal energy development. Thirteen tentative site-specific plans are being revised. The analysis of institutional factors affecting geothermal development, the outreach, and the state geothermal are discussed briefly. (MHR)

  5. Geothermal Technologies News | Geothermal Technologies | NREL

    Science.gov Websites

    for this avid biker. The reason though is unusual. Passionate about geothermal energy research, he Geothermal Energy Program In her new role, Young will work closely with NREL management to establish the lab's geothermal energy portfolio, including research and development geared toward advancing the use of

  6. Archaeological Investigations in the Gainesville Lake Area of the Tennessee-Tombigbee Waterway. Volume II. Gainesville Lake Area Ceramic Description and Chronology.

    DTIC Science & Technology

    1981-10-01

    D- A126 469 RCH EOLOGICAL INVESTIO TIONS IN THE G INESVILLE L KE /5 AREA OF THE TENNESS..(U) ALABAMA UNIV UNIVERSITY OFFICE S OF ARCHAEOLOGICAL...Entered) "._".__ _ _ _ REPORT DOCUMENTATION PAGE READ ISTRUCTIONSBEFORE COMPLETING FORM 1. REPORT NUMBER 2. GOVT ACCESSION NO. S . RECIPIENT’$ CATALOG...Archaeological Investi- Final May 1976-October 1981 gations in the Gainesville Lake Area of the S . PERFORMING ORG. REPORT NUMBER Tennessee-Tombigbee Waterway 7

  7. Consumptive Water-Use Coefficients for the Great Lakes Basin and Climatically Similar Areas

    USGS Publications Warehouse

    Shaffer, Kimberly H.; Runkle, Donna L.

    2007-01-01

    Consumptive water use is the portion of water withdrawn (for a particular use) that is evaporated, transpired, incorporated into products or crops, consumed by humans or livestock, or otherwise removed from the immediate water environment. This report, which is organized by water?use categories, includes consumptive?use coefficients for the Great Lakes Basin (including Canada) and for areas climatically similar to the Great Lakes Basin. This report also contains an annotated bibliography of consumptive water?use coefficients. Selected references are listed for consumptive?use data from elsewhere in the world. For the industrial water?use category, the median consumptive?use coefficients were 10 percent for the Great Lakes Basin, climatically similar areas, and the world; the 25th and 75th percentiles for these geographic areas were comparable within 6 percent. The combined domestic and public?supply consumptive?use statistics (median, 25th and 75th percentiles) were between 10 to 20 percent for the various geographic areas. Although summary statistics were similar for coefficients in the livestock and irrigation water?use categories for the Great Lakes Basin and climatically similar areas, statistic values for the world on a whole were substantially lower (15 to 28 percent lower). Commercial and thermoelectric power consumptive?use coefficient statistics (median, 25th, and 75th percentile) also were comparable for the Great Lakes Basin and climatically similar areas, within 2 percent. References for other countries were not found for commercial and thermoelectric power water?use categories. The summary statistics for the mining consumptive?use coefficients varied, likely because of differences in types of mining, processes, or equipment.

  8. Construction, Geologic, and Hydrologic Data for Observation Wells in the Reelfoot Lake Area, Tennessee and Kentucky

    DTIC Science & Technology

    1987-01-01

    AND HYDROLOGIC DATA FOR OBSERVATION WELLS IN THE REELFOOT LAKE AREA, TENNESSEE AND KENTUCKY ($3 1 .cz Prepared in cooperation with the...Observation Wells in The Reelfoot Lake Area, Tennessee and Kentucky 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...Prescribed by ANSI Std Z39-18 CONSTRUCTION, GEOLOGIC, AND HYDROLOGIC DATA FOR OBSERVATION WELLS IN THE REELFOOT LAKE AREA, TENNESSEE AND KENTUCKY Michael

  9. Paleoenvironmental reconstructions of Nettilling Lake area (Baffin Island, Nunavut): A multi-proxy analysis.

    NASA Astrophysics Data System (ADS)

    Beaudoin, Anne; Pienitz, Reinhard; Francus, Pierre; Zdanowicz, Christian; St-Onge, Guillaume

    2014-05-01

    The paleoclimate and paleolimnological history of several Arctic regions remains poorly known. This is the case for the area around Nettilling Lake (Baffin Island, Nunavut), the largest lake of the Canadian Arctic Archipelago. To reconstruct the past environmental history of this area, a highly innovative multi-proxy approach combining physical, magnetic, chemical and biological properties preserved in lake sediments was used. One particular goal of this study was to investigate the possible coupling between sedimentation processes observed in the lake and melt rates of nearby Penny Ice Cap. A 1-m long sediment core was retrieved from a small bay in the northeastern part of Nettilling Lake during the summer of 2010. This sampling area was chosen based on the hypothesis that incoming glacial meltwaters from Penny Ice Cap would leave a strong climate-modulated signal that would be reflected in the sedimentary sequence. The core was analyzed by both non-destructive (X-radiography (X-ray), microfluorescence-X (µ-XRF), magnetic susceptibility) and destructive (Loss On Ignition, grain size, water content, thin sections, diatoms) techniques. Radiometric AMS 14C and 210Pb/137Cs age determinations, as well as paleomagnetic measurements, were used to develop the core chronology, yielding an estimated bottom age of approximately 1365 AD. The sedimentation rate (0.15 cm.yr-1) in Nettilling Lake was found to be high compared to other Arctic lakes, due to inputs of highly turbid meltwaters from Penny Ice Cap with high suspended sediment loads. Significant correlations were found between geochemical profiles of elements linked to detrital inputs (Si, Ti, K, Ca) and melt rates from Penny Ice Cap since the 19th century. This suggests that variations in detrital elements in Nettilling Lake sediments might be used as an indirect indicator of regional climate fluctuations (e.g., summer temperatures) that determine glacier melt rates.

  10. Geothermal development plan: Cochise/Santa Cruz Counties

    NASA Astrophysics Data System (ADS)

    White, D. H.; Goldstone, L. A.

    1982-08-01

    The regional market potential for utilizing geothermal energy was evaluated. Three potential geothermal resource areas with potential for resource temperatures less than 900C (1940F) were identified. Population growth rates are expected to average 3% per year over the next 30 years in Willcox; Bowie and San Simon are expected to grow much slower. Regional employment is based on agriculture and copper mining, though future growth in trade, services and international trade is expected. A regional energy use analysis is included. Urban use, copper mining and agriculture are the principal water users in the region and substantial reductions in water use are anticipated in the future. The development plan identifies potential geothermal energy users in the region. Geothermal energy utilization projections suggest that by the year 2000, geothermal energy might economically provide the energy equivalent of 3,250,000 barrels of oil per year to the industrial sector. In addition, geothermal energy utilization might help stimulate an agricultural and livestock processing industry.

  11. Geothermal Anomaly Mapping Using Landsat ETM+ Data in Ilan Plain, Northeastern Taiwan

    NASA Astrophysics Data System (ADS)

    Chan, Hai-Po; Chang, Chung-Pai; Dao, Phuong D.

    2018-01-01

    Geothermal energy is an increasingly important component of green energy in the globe. A prerequisite for geothermal energy development is to acquire the local and regional geothermal prospects. Existing geophysical methods of estimating the geothermal potential are usually limited to the scope of prospecting because of the operation cost and site reachability in the field. Thus, explorations in a large-scale area such as the surface temperature and the thermal anomaly primarily rely on satellite thermal infrared imagery. This study aims to apply and integrate thermal infrared (TIR) remote sensing technology with existing geophysical methods for the geothermal exploration in Taiwan. Landsat 7 (L7) Enhanced Thematic Mapper Plus (ETM+) imagery is used to retrieve the land surface temperature (LST) in Ilan plain. Accuracy assessment of satellite-derived LST is conducted by comparing with the air temperature data from 11 permanent meteorological stations. The correlation coefficient of linear regression between air temperature and LST retrieval is 0.76. The MODIS LST product is used for the cross validation of Landsat derived LSTs. Furthermore, Landsat ETM+ multi-temporal brightness temperature imagery for the verification of the LST anomaly results were performed. LST Results indicate that thermal anomaly areas appear correlating with the development of faulted structure. Selected geothermal anomaly areas are validated in detail by field investigation of hot springs and geothermal drillings. It implies that occurrences of hot springs and geothermal drillings are in good spatial agreement with anomaly areas. In addition, the significant low-resistivity zones observed in the resistivity sections are echoed with the LST profiles when compared with in the Chingshui geothermal field. Despite limited to detecting the surficial and the shallow buried geothermal resources, this work suggests that TIR remote sensing is a valuable tool by providing an effective way of mapping

  12. Bathymetric map, area/capacity table, and sediment volume estimate for Millwood Lake near Ashdown, Arkansas, 2013

    USGS Publications Warehouse

    Richards, Joseph M.; Green, W. Reed

    2013-01-01

    Millwood Lake, in southwestern Arkansas, was constructed and is operated by the U.S. Army Corps of Engineers (USACE) for flood-risk reduction, water supply, and recreation. The lake was completed in 1966 and it is likely that with time sedimentation has resulted in the reduction of storage capacity of the lake. The loss of storage capacity can cause less water to be available for water supply, and lessens the ability of the lake to mitigate flooding. Excessive sediment accumulation also can cause a reduction in aquatic habitat in some areas of the lake. Although many lakes operated by the USACE have periodic bathymetric and sediment surveys, none have been completed for Millwood Lake. In March 2013, the U.S. Geological Survey (USGS), in cooperation with the USACE, surveyed the bathymetry of Millwood Lake to prepare an updated bathymetric map and area/capacity table. The USGS also collected sediment thickness data in June 2013 to estimate the volume of sediment accumulated in the lake.

  13. Ancient ice islands in salt lakes of the Central Andes

    USGS Publications Warehouse

    Hurlbert, S.H.; Chang, Cecily C.Y.

    1984-01-01

    Massive blocks of freshwater ice and frozen sediments protrude from shallow, saline lakes in the Andes of southwestern Bolivia and northeastern Chile. These ice islands range up to 1.5 kilometers long, stand up to 7 meters above the water surface, and may extend out tens of meters and more beneath the unfrozen lake sediments. The upper surfaces of the islands are covered with dry white sediments, mostly aragonite or calcite. The ice blocks may have formed by freezing of the fresh pore water of lake sediments during the "little ice age." The largest blocks are melting rapidly because of possibly recent increases in geothermal heat flux through the lake bottom and undercutting by warm saline lake water during the summer.

  14. Structural controls on fluid circulation at the Caviahue-Copahue Volcanic Complex (CCVC) geothermal area (Chile-Argentina), revealed by soil CO2 and temperature, self-potential, and helium isotopes

    NASA Astrophysics Data System (ADS)

    Roulleau, Emilie; Bravo, Francisco; Pinti, Daniele L.; Barde-Cabusson, Stéphanie; Pizarro, Marcela; Tardani, Daniele; Muñoz, Carlos; Sanchez, Juan; Sano, Yuji; Takahata, Naoto; de la Cal, Federico; Esteban, Carlos; Morata, Diego

    2017-07-01

    Natural geothermal systems are limited areas characterized by anomalously high heat flow caused by recent tectonic or magmatic activity. The heat source at depth is the result of the emplacement of magma bodies, controlled by the regional volcano-tectonic setting. In contrast, at a local scale a well-developed fault-fracture network favors the development of hydrothermal cells, and promotes the vertical advection of fluids and heat. The Southern Volcanic Zone (SVZ), straddling Chile and Argentina, has an important, yet unexplored and undeveloped geothermal potential. Studies on the lithological and tectonic controls of the hydrothermal circulation are therefore important for a correct assessment of the geothermal potential of the region. Here, new and dense self-potential (SP), soil CO2 and temperature (T) measurements, and helium isotope data measured in fumaroles and thermal springs from the geothermal area located in the north-eastern flank of the Copahue volcanic edifice, within the Caviahue Caldera (the Caviahue-Copahue Volcanic Complex - CCVC) are presented. Our results allowed to the constraint of the structural origin of the active thermal areas and the understanding of the evolution of the geothermal system. NE-striking faults in the area, characterized by a combination of SP, CO2, and T maxima and high 3He/4He ratios (up to 8.16 ± 0.21Ra, whereas atmospheric Ra is 1.382 × 10- 6), promote the formation of vertical permeability preferential pathways for fluid circulation. WNW-striking faults represent low-permeability pathways for hydrothermal fluid ascent, but promote infiltration of meteoric water at shallow depths, which dilute the hydrothermal input. The region is scattered with SP, CO2, and T minima, representing self-sealed zones characterized by impermeable altered rocks at depth, which create local barriers for fluid ascent. The NE-striking faults seem to be associated with the upflowing zones of the geothermal system, where the boiling process

  15. The Cottonwood Lake study area, a long-term wetland ecosystem monitoring site

    USGS Publications Warehouse

    Mushet, David M.; Euliss, Ned H.

    2012-01-01

    The Cottonwood Lake study area is one of only three long-term wetland ecosystem monitoring sites in the prairie pothole region of North America; the other two are Orchid Meadows in South Dakota and St. Denis in Saskatchewan. Of the three, Cottonwood Lake has, by far, the longest continuous data-collection record. Research was initiated at the study area in 1966, and intensive investigations of the hydrology, chemistry, and biology of prairie pothole wetlands continue at the site today. This fact sheet describes the study area, provides an overview of wetland ecology research that has been conducted at the site in the past, and provides an introduction to current work being conducted at the study area by USGS scientists.

  16. Are modern geothermal waters in northwest Nevada forming epithermal gold deposits?

    USGS Publications Warehouse

    Breit, George N.; Hunt, Andrew G.; Wolf, Ruth E.; Koenig, Alan E.; Fifarek, Richard; Coolbaugh, Mark F.

    2010-01-01

    Hydrothermal systems currently are active near some gold deposits in northwestern Nevada. Possible links of these modern systems to gold mineralization were evaluated by chemically and isotopically analyzing water samples from the Brady, Dixie Valley, Humboldt House, San Emidio-Empire, Soda Lake, and Wabuska geothermal areas. In addition, quartz veins from Humboldt House and the adjacent Florida Canyon Mine were analyzed to compare ore and gangue phases with those predicted to form from proximal hydrothermal fluids.Nearly all water samples are alkali-chloride-type. Total dissolved solids range from 800 to 3900 mg/L, and pH varies from 5.6 to 7.8. Geochemical modeling with SOLVEQ, WATCH, and CHILLER predict the precipitation of silica in all systems during cooling. Anhydrite, calcite, barite, pyrite, base-metal sulfides, and alumino-silicates are variably saturated at calculated reservoir temperatures and also precipitate during boiling/cooling of some fluids. Measured dissolved gold concentrations are low (<0.2μg/L), but are generally consistent with contents predicted by equilibrium of sampled solutions with elemental gold at reservoir temperatures.  Although the modern geothermal waters can precipitate ore minerals, the low gold and other ore metal concentrations require very large fluid volumes to form a deposit of economic interest.

  17. 77 FR 30320 - General Management Plan/Environmental Impact Statement, Ross Lake National Recreation Area, North...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-22

    ... Management Plan/Environmental Impact Statement, Ross Lake National Recreation Area, North Cascades National... Impact Statement for the new General Management Plan (GMP) for Ross Lake National Recreation Area, part... Wilderness Act of 1988. The full range of foreseeable environmental consequences from implementing the...

  18. Seasonal and geothermal production variations in concentrations of He and CO2 in soil gases, Roosevelt Hot Springs Known Geothermal Resource Area, Utah, U.S.A.

    USGS Publications Warehouse

    Hinkle, M.E.

    1991-01-01

    To increase understanding of natural variations in soil gas concentrations, CO2, He, O2 and N2 were measured in soil gases collected regularly for several months from four sites at the Roosevelt Hot Springs Known Geothermal Resource Area, Utah. Soil temperature, air temperature, per cent relative humidity, barometric pressure and amounts of rain and snowfall were also monitored to determine the effect of meteorological parameters on concentrations of the measured gases. Considerable seasonal variation existed in concentrations of CO2 and He. The parameters that most affected the soil-gas concentrations were soil and air temperatures. Moisture from rain and snow probably affected the soil-gas concentrations also. However, annual variations in meteorological parameters did not appear to affect measurements of anomalous concentrations in samples collected within a time period of a few days. Production from some of the geothermal wells probably affected the soil-gas concentrations. ?? 1990.

  19. Prediction and discovery of new geothermal resources in the Great Basin: Multiple evidence of a large undiscovered resource base

    USGS Publications Warehouse

    Coolbaugh, M.F.; Raines, G.L.; Zehner, R.E.; Shevenell, L.; Williams, C.F.

    2006-01-01

    Geothermal potential maps by themselves cannot directly be used to estimate undiscovered resources. To address the undiscovered resource base in the Great Basin, a new and relatively quantitative methodology is presented. The methodology involves three steps, the first being the construction of a data-driven probabilistic model of the location of known geothermal systems using weights of evidence. The second step is the construction of a degree-of-exploration model. This degree-of-exploration model uses expert judgment in a fuzzy logic context to estimate how well each spot in the state has been explored, using as constraints digital maps of the depth to the water table, presence of the carbonate aquifer, and the location, depth, and type of drill-holes. Finally, the exploration model and the data-driven occurrence model are combined together quantitatively using area-weighted modifications to the weights-of-evidence equations. Using this methodology in the state of Nevada, the number of undiscovered geothermal systems with reservoir temperatures ???100??C is estimated at 157, which is 3.2 times greater than the 69 known systems. Currently, nine of the 69 known systems are producing electricity. If it is conservatively assumed that an additional nine for a total of 18 of the known systems will eventually produce electricity, then the model predicts 59 known and undiscovered geothermal systems are capable of producing electricity under current economic conditions in the state, a figure that is more than six times higher than the current number. Many additional geothermal systems could potentially become economic under improved economic conditions or with improved methods of reservoir stimulation (Enhanced Geothermal Systems).This large predicted geothermal resource base appears corroborated by recent grass-roots geothermal discoveries in the state of Nevada. At least two and possibly three newly recognized geothermal systems with estimated reservoir temperatures

  20. Exploring geothermal structures in the Ilan Plain, Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, Chien-Ying; Shih, Ruey-Chan; Chung, Chen-Tung; Huang, Ming-Zi; Kuo, Hsuan-Yu

    2017-04-01

    The Ilan Plain in northeast Taiwan is located at the southwestern tip of the Okinawa Trough, which extends westward into the Taiwan orogeny. The Ilan Plain covered by thick sediments is clipped by the Hsuehshan Range in the northern side and the Central Range in the southern side. High geothermal gradients with plenteous hot springs of this area may result from igneous intrusion associated with the back-arc spreading of the Okinawa Trough. In this study, we use reflection seismic survey to explore underground structures in the whole Ilan Plain, especially in SanShin, Wujie, and Lize area. We aim to find the relationship between underground structures and geothermal forming mechanism. The research uses reflection seismic survey to investigate the high geothermal gradient area with two mini-vibrators and 240-channel system. The total length of seismic lines is more than 30 kilometers. The results show that alluvial sediments covering the area about 400 600 meters thick and then thin out to the west in SanShin area. In SanShin , the Taiyaqiao anticline in Hsuehshan Range has entered the plain area and is bounded by the Zhuoshui fault (south) and the Zailian fault (north). In Wujie and Lize , Zhuoshui fault cut through a strong reflector which is the top of the gravel layer near the bottom of the alluvial layer, while the SanShin fault seems to cut near very shallow strata. These two faults are a strike-slip fault with a bit of normal fault component distributing over a range of 600 meters. In Ilan Plain, the geothermal forming mechanism is controlled by anticlines and faults. The hydrothermal solution which migrates upward along these anticline or fault zones to the shallow part causing high geothermal gradients in these areas.

  1. Geothermal Exploration and Resource Assessment | Geothermal Technologies |

    Science.gov Websites

    , drilling, and resource assessments and the widespread adoption of under-utilized low-temperature resources -temperature geothermal resource technologies. Drilling The drilling of wells to find and develop geothermal low-temperature, sedimentary, co-produced, and enhanced geothermal system resources. We also work to

  2. NANA Geothermal Assessment Program Final Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jay Hermanson

    2010-06-22

    In 2008, NANA Regional Corporation (NRC) assessed geothermal energy potential in the NANA region for both heat and/or electricity production. The Geothermal Assessment Project (GAP) was a systematic process that looked at community resources and the community's capacity and desire to develop these resources. In October 2007, the US Department of Energy's Tribal Energy Program awarded grant DE-FG36-07GO17075 to NRC for the GAP studies. Two moderately remote sites in the NANA region were judged to have the most potential for geothermal development: (1) Granite Mountain, about 40 miles south of Buckland, and (2) the Division Hot Springs area in themore » Purcell Mountains, about 40 miles south of Shungnak and Kobuk. Data were collected on-site at Granite Mountain Hot Springs in September 2009, and at Division Hot Springs in April 2010. Although both target geothermal areas could be further investigated with a variety of exploration techniques such as a remote sensing study, a soil geochemical study, or ground-based geophysical surveys, it was recommended that on-site or direct heat use development options are more attractive at this time, rather than investigations aimed more at electric power generation.« less

  3. The Geothermal Potential, Current and Opportunity in Taiwan

    NASA Astrophysics Data System (ADS)

    Song, Sheng-Rong

    2016-04-01

    Located in the west Pacific Rim of Fire, Taiwan possesses rich geothermal resources due to volcanic activities and rapid uplifting of plate collision. Based on available data prior to 1980, Taiwan may have about 1 GWe of potential shallow geothermal energy, which is less than 3% of the national gross power generation. A 3-Mw pilot power plant, therefore, was constructed in 1981 and terminated in 1993 in the Chingshui geothermal field of Ilan, northeastern Taiwan. Recently, one of the National Science & Technology Program (NSTP) projects has been conducting research and reevaluating the island-wide deep geothermal energy. Four hot potential sites have been recognized. They are: (1) Tatun Volcano Group of northern Taiwan; (2) I-Lan Plain of NE Taiwan; (3) Lu-Shan area of Central Taiwan; and (4) Hua-Tung area of eastern Taiwan. We found that the geothermal resource in Taiwan may be as high as 160 GWe, with 33.6 GWe of exploitable geothermal energy. There are no any commercial geothermal power plants until now in Taiwan, although the potential is great. However, geothermal energy has been listed as one of major tasks of National Energy Program, Phase II (NEP-II) in Taiwan. We will conduct more detailed geothermal energy surveys on some proposed hot sites and to construct an EGS pilot geothermal plant with 1 MWe capability in a few years. Currently, there are three nuclear power plants, named No. 1, 2 & 3, in operations, which produce 16.5% gross generation of electricity and one (No. 4) is under construction, but is stopped and sealed now in Taiwan. Furthermore, the life-span of 40-year operation for those three power plants will be close-at hand and retire in 2018-2019, 2021-2023 and 2024-2025, respectively. Therefore, to find alternative energy sources, especially on the clean, renewable and sustainable ones for generating electricity are emergent and important for Taiwan's government in next few years. Among various energy sources, geothermal energy can be as base

  4. Changes in surface area of the Böön Tsagaan and Orog lakes (Mongolia, Valley of the Lakes, 1974-2013) compared to climate and permafrost changes

    NASA Astrophysics Data System (ADS)

    Szumińska, Danuta

    2016-07-01

    The main aim of the study is the analysis of changes in surface area of lake Böön Tsagaan (45°35‧N, 99°8‧E) and lake Orog (45°3‧N, 100°44‧E) taking place in the last 40 years in the context of climate conditions and permafrost degradation. The lakes, located in Central Mongolia, at the borderline of permafrost range are fed predominantly by river waters and groundwater from the surrounding mountain areas, characterized by continuous and discontinuous permafrost occurrence - mostly the Khangai. The analysis of the Böön Tsagaan and Orog lake surface area in 1974-2013 was conducted based on satellite images, whereas climate conditions were analysed using the NOAA climate data and CRU dataset. Principal Component Analysis (PCA) was used to study the relationship patterns between the climatic factors and changes in the surface area of the lakes. A tendency for a decrease in surface area, intermittent with short episodes of resupply, was observed in both studied lakes. Climate changes recorded in the analysed period had both direct and indirect impacts on water supply to lakes. Taking into account the results of PCA analysis, the most significant factors include: fluctuation of annual precipitation, increase in air temperature and thickness of snow cover. The extended duration of snow cover in the last decades of the 20th century may constitute a key factor in relation to permafrost degradation.

  5. Archaeological Investigations in the Gainesville Lake Area of the Tennessee-Tombigbee Waterway. Volume I. The Gainesville Lake Area Excavations.

    DTIC Science & Technology

    1981-01-01

    97 71. Site 1Pi61, Removing Trees ........ .................. . 97 72. Site lPi6l, Testing the Midden ....... ................ . 97 6...the use of plant and animal species changes through time. Volume IV also describes the human skeletal remains from all excavated sites and discusses the...Gainesville Lake area were cultural features. A few 5 features resulted from forces other than human behavior ( tree roots, ro- dent burrows, erosional gullies

  6. Reservoir depletion at The Geysers geothermal area, California, shown by four-dimensional seismic tomography

    USGS Publications Warehouse

    Gunasekera, R.C.; Foulger, G.R.; Julian, B.R.

    2003-01-01

    Intensive geothermal exploitation at The Geysers geothermal area, California, induces myriads of small-magnitude earthquakes that are monitored by a dense, permanent, local seismometer network. Using this network, tomographic inversions were performed for the three-dimensional Vp and Vp/Vs structure of the reservoir for April 1991, February 1993, December 1994, October 1996, and August 1998. The extensive low-Vp/Vs anomaly that occupies the reservoir grew in strength from a maximum of 9% to a maximum of 13.4% during the 7-year study period. This is attributed to depletion of pore liquid water in the reservoir and replacement with steam. This decreases Vp by increasing compressibility, and increases Vs because of reduction in pore pressure and the drying of argillaceous minerals, e.g., illite, which increase the shear modulus. These effects serendipitously combine to lower Vp/Vs, resulting in a strong overall effect that provides a convenient tool for monitoring reservoir depletion. Variations in the Vp and Vs fields indicate that water depletion is the dominant process in the central part of the exploited reservoir, and pressure reduction and mineral drying in the northwest and southeast parts of the reservoir. The rate at which the Vp/Vs anomaly grew in strength in the period 1991-1998 suggests most of the original anomaly was caused by exploitation. Continuous monitoring of Vp, Vs, and Vp/Vs is an effective geothermal reservoir depletion monitoring tool and can potentially provide information about depletion in parts of the reservoir that have not been drilled.

  7. Climatic and lake temperature data for Wetland P1, Cottonwood Lake Area, Stutsman County, North Dakota, 1982-87

    USGS Publications Warehouse

    Parkhurst, Renee S.; Sturrock, A.M.; Rosenberry, D.O.; Winter, T.C.

    1995-01-01

    Research on the hydrology of Wetland P1 and the Cottonwood Lake Area includes the study of evaporation. Presented here in a graphical format are those data collected during the open-water seasons of 1982-87 that were needed for energy- budget and mass-transfer evaporation studies. The data include air temperatures, water surface and lake-bottom temperatures, windspeed, radiation, humidity, and precipitation. Data were collected at a raft station and two land stations.

  8. Complete Mitochondrial and Plastid Genomes of the Green Microalga Trebouxiophyceae sp. Strain MX-AZ01 Isolated from a Highly Acidic Geothermal Lake

    PubMed Central

    Martínez-Romero, Esperanza

    2012-01-01

    We report the complete organelle genome sequences of Trebouxiophyceae sp. strain MX-AZ01, an acidophilic green microalga isolated from a geothermal field in Mexico. This eukaryote has the remarkable ability to thrive in a particular shallow lake with emerging hot springs at the bottom, extremely low pH, and toxic heavy metal concentrations. Trebouxiophyceae sp. MX-AZ01 represents one of few described photosynthetic eukaryotes living in such a hostile environment. The organelle genomes of Trebouxiophyceae sp. MX-AZ01 are remarkable. The plastid genome sequence currently presents the highest G+C content for a trebouxiophyte. The mitochondrial genome sequence is the largest reported to date for the Trebouxiophyceae class of green algae. The analysis of the genome sequences presented here provides insight into the evolution of organelle genomes of trebouxiophytes and green algae. PMID:23104370

  9. Anthropic influences on the sedimentation rates of lakes situated in different geographic areas.

    PubMed

    Simon, Hedvig; Kelemen, Szabolcs; Begy, Róbert-Csaba

    2017-07-01

    The aim of this study is to determine the effects of natural and anthropic events occurring in the last 30 years in the catchment areas of four Romanian lakes (St. Anna Lake, Red Lake, Vârşolţ Lake and Matiţa Lake) originating from four different geomorphologic areas. A total of eleven sediment cores have been processed for age and sedimentation rate determination using the 210 Pb dating method. Total 210 Pb was measured via alpha spectrometry by 210 Po using PIPS detectors, while supported 210 Pb was measured by 226 Ra using HPGe detectors. Ages and sedimentation rates were calculated using the CRS model. The values of the sedimentation rates have grown multiply in the last three decades: 2.66 times in case of the St. Anna Lake (from 0.06 ± 0.01 g/cm 2 y to 0.16 ± 0.02 g/cm 2 y), up to 6.72 times in case of Red Lake (0.36 ± 0.04 g/cm 2 y to 2.42 ± 0.36 g/cm 2 y), 4.02 times in case of Vârşolţ Lake (04 g/cm 2 y to 1.53 ± 0.18 g/cm 2 y) and up to 16.18 times in case of Matiţa Lake (0.27 ± 0.03 g/cm 2 y to 4.37 ± 0.32). Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Cluster analysis as a tool for evaluating the exploration potential of Known Geothermal Resource Areas

    DOE PAGES

    Lindsey, Cary R.; Neupane, Ghanashym; Spycher, Nicolas; ...

    2018-01-03

    Although many Known Geothermal Resource Areas in Oregon and Idaho were identified during the 1970s and 1980s, few were subsequently developed commercially. Because of advances in power plant design and energy conversion efficiency since the 1980s, some previously identified KGRAs may now be economically viable prospects. Unfortunately, available characterization data vary widely in accuracy, precision, and granularity, making assessments problematic. In this paper, we suggest a procedure for comparing test areas against proven resources using Principal Component Analysis and cluster identification. The result is a low-cost tool for evaluating potential exploration targets using uncertain or incomplete data.

  11. Cluster analysis as a tool for evaluating the exploration potential of Known Geothermal Resource Areas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lindsey, Cary R.; Neupane, Ghanashym; Spycher, Nicolas

    Although many Known Geothermal Resource Areas in Oregon and Idaho were identified during the 1970s and 1980s, few were subsequently developed commercially. Because of advances in power plant design and energy conversion efficiency since the 1980s, some previously identified KGRAs may now be economically viable prospects. Unfortunately, available characterization data vary widely in accuracy, precision, and granularity, making assessments problematic. In this paper, we suggest a procedure for comparing test areas against proven resources using Principal Component Analysis and cluster identification. The result is a low-cost tool for evaluating potential exploration targets using uncertain or incomplete data.

  12. Detection of geothermal anomalies in Tengchong, Yunnan Province, China from MODIS multi-temporal night LST imagery

    NASA Astrophysics Data System (ADS)

    Li, H.; Kusky, T. M.; Peng, S.; Zhu, M.

    2012-12-01

    Thermal infrared (TIR) remote sensing is an important technique in the exploration of geothermal resources. In this study, a geothermal survey is conducted in Tengchong area of Yunnan province in China using multi-temporal MODIS LST (Land Surface Temperature). The monthly night MODIS LST data from Mar. 2000 to Mar. 2011 of the study area were collected and analyzed. The 132 month average LST map was derived and three geothermal anomalies were identified. The findings of this study agree well with the results from relative geothermal gradient measurements. Finally, we conclude that TIR remote sensing is a cost-effective technique to detect geothermal anomalies. Combining TIR remote sensing with geological analysis and the understanding of geothermal mechanism is an accurate and efficient approach to geothermal area detection.

  13. 75 FR 6218 - New Melones Lake Area Resource Management Plan, Tuolumne and Calaveras Counties, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-08

    ... DEPARTMENT OF THE INTERIOR Bureau of Reclamation New Melones Lake Area Resource Management Plan...) has made available for public review a Final RMP/EIS for the New Melones Lake Area. The Final RMP/EIS... Dan Holsapple, Acting New Melones Resource Manager, Bureau of Reclamation, at 209-536- 9094...

  14. State-coupled low-temperature geothermal-resource-assessment program, Fiscal Year 1980. Final technical report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Icerman, L.; Starkey, A.; Trentman, N.

    1981-08-01

    Magnetic, gravity, seismic-refraction, and seismic-reflection profiles across the Las Alturas Geothermal Anomaly, New Mexico, are presented. Studies in the Socorro area include the following: seismic measurements of the tertiary fill in the Rio Grande Depression west of Socorro, geothermal data availability for computer simulation in the Socorro Peak KGRA, and ground water circulation in the Socorro Geothermal Area. Regional geothermal exploration in the Truth or Consequences Area includes: geological mapping of the Mud Springs Mountains, hydrogeology of the thermal aquifer, and electrical-resistivity investigation of the geothermal potential. Other studies included are: geothermal exploration with electrical methods near Vado, Chamberino, andmore » Mesquite; a heat-flow study of Dona Ana County; preliminary heat-flow assessment of Southeast Luna County; active fault analysis and radiometric dating of young basalts in southern New Mexico; and evaluation of the geothermal potential of the San Juan Basin in northwestern New Mexico.« less

  15. Long-Term Remote Monitoring of Three Typical Lake Area Variations in the Northwest China Over the Past 40 Years

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Lu, Y.; Li, Y.; Yue, H.

    2018-04-01

    water resources management and sustainable development strategy, but also provide reference for assessing the impact of climate change and human activities. This paper selects three inland lakes in Northwest China, using Landsat MSS/TM/ETM+/OLI data from 1970 to 2015, Normalized Difference Water Index (NDWI) and Modified Normalized Difference Water Index (MNDWI) were used to extract lake area and analysed the dynamic trends. Meteorological station rainfall, evaporation and other meteorological data of the lakes were used to analyse reasons for the area change. The results showed that area of Hongjiannao Lake in the past 40 a was reduced, the groundwater impoundment and underground coal mining are the main cause of area reduction; the area of Bosten Lake in recent 40 a showed a decreasing trend after the first increase, the area was mainly affected by the surface runoff and snowmelt; the area of Qinghai Lake in the past 40 a shows a trend of decreasing first and then increasing, the change of its area is mainly affected by regional precipitation and the inflow.

  16. Coniform stromatolites from geothermal systems, North Island, New Zealand

    USGS Publications Warehouse

    Jones, Brian; Renaut, Robin W.; Rosen, Michael R.; Ansdell, Kevin M.

    2002-01-01

    Coniform stromatolites are found in several sites in the Tokaanu and Whakarewarewa geothermal areas of North Island, New Zealand. At Tokaanu, silicification of these stromatolites is taking place in Kirihoro, a shallow hot springfed pool. At Whakarewarewa, subfossil silicified coniform stromatolites are found on the floor of "Waikite Pool" on the discharge apron below Waikite Geyser, and in an old sinter succession at Te Anarata. The microbes in the coniform stromatolites from Tokaanu, Waikite Pool, and Te Anarata have been well preserved through rapid silicification. Nevertheless, subtle differences in the silicification style induced morphological variations that commonly mask or alter morphological features needed for identification of the microbes in terms of extant taxa. The coniform stromatolites in the New Zealand hotspring pools are distinctive because (1) they are formed of upward tapering (i.e., conical) columns, (2) neighboring columns commonly are linked by vertical sheets or bridges, (3) internally, they are formed of alternating high- and low-porosity laminae that have a conical vertical profile, and (4) Phormidium form more than 90% of the biota. As such, they are comparable to modern coniform mats and stromatolites found in the geothermal systems of Yellowstone National Park and ice-covered lakes in Antarctica. Formation of the coniform stromatolites is restricted to pools that are characterized by low current energy and a microflora that is dominated by Phormidium. These delicate and intricate stromatolites could not form in areas characterized by fast flowing water or a diverse microflora. Thus, it appears that the distribution of these distinctive stromatolites is controlled by biological constraints that are superimposed on environmental needs.

  17. NATIONAL GEOTHERMAL DATA SYSTEM (NGDS) GEOTHERMAL DATA DOMAIN: ASSESSMENT OF GEOTHERMAL COMMUNITY DATA NEEDS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson, Arlene; Blackwell, David; Chickering, Cathy

    2013-01-01

    To satisfy the critical need for geothermal data to ad- vance geothermal energy as a viable renewable ener- gy contender, the U.S. Department of Energy is in- vesting in the development of the National Geother- mal Data System (NGDS). This paper outlines efforts among geothermal data providers nationwide to sup- ply cutting edge geo-informatics. NGDS geothermal data acquisition, delivery, and methodology are dis- cussed. In particular, this paper addresses the various types of data required to effectively assess geother- mal energy potential and why simple links to existing data are insufficient. To create a platform for ready access by allmore » geothermal stakeholders, the NGDS in- cludes a work plan that addresses data assets and re- sources of interest to users, a survey of data provid- ers, data content models, and how data will be ex- changed and promoted, as well as lessons learned within the geothermal community.« less

  18. View of Lake Mead and Las Vegas, Nevada area from Sklyab

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A vertical view of the Lake Mead and Las Vegas, Nevada area as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. Lake Mead is water of the Colorado River impounded by Hoover Dam. Most of the land in the picture is Nevada, however, a part of the northwest corner of Arizona can be seen.

  19. Structural Inventory of Great Basin Geothermal Systems and Definition of Favorable Structural Settings

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    Over the course of the entire project, field visits were made to 117 geothermal systems in the Great Basin region. Major field excursions, incorporating visits to large groups of systems, were conducted in western Nevada, central Nevada, northwestern Nevada, northeastern Nevada, east‐central Nevada, eastern California, southern Oregon, and western Utah. For example, field excursions to the following areas included visits of multiple geothermal systems: - Northwestern Nevada: Baltazor Hot Spring, Blue Mountain, Bog Hot Spring, Dyke Hot Springs, Howard Hot Spring, MacFarlane Hot Spring, McGee Mountain, and Pinto Hot Springs in northwest Nevada. - North‐central to northeastern Nevada: Beowawe, Crescent Valley (Hot Springs Point), Dann Ranch (Hand‐me‐Down Hot Springs), Golconda, and Pumpernickel Valley (Tipton Hot Springs) in north‐central to northeast Nevada. - Eastern Nevada: Ash Springs, Chimney Hot Spring, Duckwater, Hiko Hot Spring, Hot Creek Butte, Iverson Spring, Moon River Hot Spring, Moorman Spring, Railroad Valley, and Williams Hot Spring in eastern Nevada. - Southwestern Nevada‐eastern California: Walley’s Hot Spring, Antelope Valley, Fales Hot Springs, Buckeye Hot Springs, Travertine Hot Springs, Teels Marsh, Rhodes Marsh, Columbus Marsh, Alum‐Silver Peak, Fish Lake Valley, Gabbs Valley, Wild Rose, Rawhide‐ Wedell Hot Springs, Alkali Hot Springs, and Baileys/Hicks/Burrell Hot Springs. - Southern Oregon: Alvord Hot Spring, Antelope Hot Spring‐Hart Mountain, Borax Lake, Crump Geyser, and Mickey Hot Spring in southern Oregon. - Western Utah: Newcastle, Veyo Hot Spring, Dixie Hot Spring, Thermo, Roosevelt, Cove Fort, Red Hill Hot Spring, Joseph Hot Spring, Hatton Hot Spring, and Abraham‐Baker Hot Springs. Structural controls of 426 geothermal systems were analyzed with literature research, air photos, google‐Earth imagery, and/or field reviews (Figures 1 and 2). Of the systems analyzed, we were able to determine the structural settings

  20. [Fleas on small mammals in the surrounding area of Erhai Lake].

    PubMed

    Dong, Wen-Ge; Guo, Xian-Guo; Men, Xing-Yuan; Gong, Zheng-Da; Wu, Dian; Zhang, Zheng-Kun; Zhang, Li-Yun

    2009-12-01

    To investigate the distribution pattern, species diversity and community structure of fleas on small mammals in the surrounding area of Erhai Lake, and the relationship between fleas and their hosts. Different geographical areas surrounding the Erhai Lake in Yunnan were selected as investigated spots. Small mammals were captured with baited cages. The cage-traps were examined and re-baited each morning. All fleas on the hosts were collected and identified. The richness (S), evenness (J'), diversity index (H'), dominance index (C'), total ectoparasite infestation rate (Rpt), total ectoparasite infestation index (Ipt), and constituent ratio (Cr) were used to measure the community structure. Altogether, 3,303 small mammals and 3,243 fleas were collected. From the 21 species of small mammal hosts, 13 species of fleas were identified. In southern area of the Lake, the species richness (21 species of small mammals & 12 species of fleas) was highest among the three selected areas. Seventeen species of small mammals and 8 species of fleas were found in eastern area, and only 13 species of small mammals and 7 species of fleas found in the west. This implied the probable influences of ecological environments on the fleas and their corresponding hosts. The community structure of fleas on small mammals was complex. The species diversity, species composition, community structure and distribution pattern of fleas were simultaneously influenced by the hosts' body surface microenvironment and the macroenvironment (habitat). The fleas are commonly distributed in small mammals in the areas and their communities are related to host species and the habitats.

  1. Beowawe Geothermal Area evaluation program. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Iovenitti, J. L

    Several exploration programs were conducted at the Beowawe Geothermal Prospect, Lander and Eureka County, Nevada. Part I, consisting of a shallow temperature hole program, a mercury soil sampling survey, and a self-potential survey were conducted in order to select the optimum site for an exploratory well. Part II consisted of drilling a 5927-foot exploratory well, running geophysical logs, conducting a drill stem test (2937-3208 feet), and a short-term (3-day) flow test (1655-2188 feet). All basic data collected is summarized.

  2. National Surface Water Survey, western wilderness area lakes: environmental assessment. Draft

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1985-03-01

    The US Environmental Protection Agency (EPA) is proposing to sample 498 lakes in federally designated wilderness areas and national parks during the western part of the National Surface Water Survey (NSW). The NSWS has been undertaken to provide high quality data for evaluating the nature and extent of acid deposition throughout the United States. Sampling protocols established for the national survey call for the use of helicopters to gain access to lakes for sampling. Helicopters have already been used in the eastern and midwestern parts of the survey. The US Forest Service (FS) and the National Park Service (NPS) willmore » have to decide which sampling plan for wilderness areas, if any, can be approved under the Wilderness Act of 1964. This Environmental Assessment (EA) has been prepared to evaluate the environmental consequences of alternative means of gaining access to wilderness areas to meet the objectives of the NSWS. Based on this evaluation, EPA has reviewed the possible sampling alternatives and reached a conclusion on the preferred alternative. This assessment is being provided to the FS and the NPS for their use in evaluating the alternatives, including EPA's preferred one. As a result of its evaluation, EPA believes that wilderness area lakes should be included in the survey and that the preferred means of access is using helicopters. 94 references, 14 figures, 18 tables.« less

  3. Geothermal resources and reserves in Indonesia: an updated revision

    NASA Astrophysics Data System (ADS)

    Fauzi, A.

    2015-02-01

    More than 300 high- to low-enthalpy geothermal sources have been identified throughout Indonesia. From the early 1980s until the late 1990s, the geothermal potential for power production in Indonesia was estimated to be about 20 000 MWe. The most recent estimate exceeds 29 000 MWe derived from the 300 sites (Geological Agency, December 2013). This resource estimate has been obtained by adding all of the estimated geothermal potential resources and reserves classified as "speculative", "hypothetical", "possible", "probable", and "proven" from all sites where such information is available. However, this approach to estimating the geothermal potential is flawed because it includes double counting of some reserve estimates as resource estimates, thus giving an inflated figure for the total national geothermal potential. This paper describes an updated revision of the geothermal resource estimate in Indonesia using a more realistic methodology. The methodology proposes that the preliminary "Speculative Resource" category should cover the full potential of a geothermal area and form the base reference figure for the resource of the area. Further investigation of this resource may improve the level of confidence of the category of reserves but will not necessarily increase the figure of the "preliminary resource estimate" as a whole, unless the result of the investigation is higher. A previous paper (Fauzi, 2013a, b) redefined and revised the geothermal resource estimate for Indonesia. The methodology, adopted from Fauzi (2013a, b), will be fully described in this paper. As a result of using the revised methodology, the potential geothermal resources and reserves for Indonesia are estimated to be about 24 000 MWe, some 5000 MWe less than the 2013 national estimate.

  4. Vegetation component of geothermal EIS studies: Introduced plants, ecosystem stability, and geothermal development

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    This paper contributes new information about the impacts from introduced plant invasions on the native Hawaiian vegetation as consequences of land disturbance and geothermal development activities. In this regard, most geothermal development is expected to act as another recurring source of physical disturbance which favors the spread and maintenance of introduced organisms throughout the region. Where geothermal exploration and development activities extend beyond existing agricultural and residential development, they will become the initial or sole source of disturbance to the naturalized vegetation of the area. Kilauea has a unique ecosystem adapted to the dynamics of a volcanically active landscape. Themore » characteristics of this ecosystem need to be realized in order to understand the major threats to the ecosystem and to evaluate the effects of and mitigation for geothermal development in Puna. The native Puna vegetation is well adapted to disturbances associated with volcanic eruption, but it is ill-adapted to compete with alien plant species in secondary disturbances produced by human activities. Introduced plant and animal species have become a major threat to the continued presence of the native biota in the Puna region of reference.« less

  5. Vegetation component of geothermal EIS studies: Introduced plants, ecosystem stability, and geothermal development

    NASA Astrophysics Data System (ADS)

    1994-10-01

    This paper contributes new information about the impacts from introduced plant invasions on the native Hawaiian vegetation as consequences of land disturbance and geothermal development activities. In this regard, most geothermal development is expected to act as another recurring source of physical disturbance which favors the spread and maintenance of introduced organisms throughout the region. Where geothermal exploration and development activities extend beyond existing agricultural and residential development, they will become the initial or sole source of disturbance to the naturalized vegetation of the area. Kilauea has a unique ecosystem adapted to the dynamics of a volcanically active landscape. The characteristics of this ecosystem need to be realized in order to understand the major threats to the ecosystem and to evaluate the effects of and mitigation for geothermal development in Puna. The native Puna vegetation is well adapted to disturbances associated with volcanic eruption, but it is ill-adapted to compete with alien plant species in secondary disturbances produced by human activities. Introduced plant and animal species have become a major threat to the continued presence of the native biota in the Puna region.

  6. Overview of Resources for Geothermal Absorption Cooling for Buildings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Xiaobing; Gluesenkamp, Kyle R; Mehdizadeh Momen, Ayyoub

    2015-06-01

    This report summarizes the results of a literature review in three areas: available low-temperature/coproduced geothermal resources in the United States, energy use for space conditioning in commercial buildings, and state of the art of geothermal absorption cooling.

  7. Aspects of the bottom sediment of Lake Nakaumi and Honjo area ~ featuring with organic matter and the Sulfides ~

    NASA Astrophysics Data System (ADS)

    Shinohara, R.

    2015-12-01

    Lake Nakaumi is a brackish water located at southwest Japan. Seawater from the Sea of Japan inflows through Sakai-strait, and river water flows through the Oohashi River into this lake. Lake Nakaumi is characterized with hypoxic and/or anoxic condition of bottom water derived with the distinct stratification of salinity in summer season. In this lake, a public project had been carried out for land reclamation since 1963. Honjo Area located to the north part of Lake Nakaumi, was semi-separated from Lake Nakaumi by reclamation dikes constructed for this project at 1981. However, this public project was aborted with the change of social conditions. To the effective utilization of the area, the partial removal of dike was carried out. Seawater from Sakai-strait flows directly into Honjo Area again. Environmental change of the lake is expected by this inflow of the seawater in Lake Nakaumi and Honjo Area after this restoration. It is well known that the surface sediment reflects the environment of lake bottom. The organic matter and the sulfides in sediment are good indicators of sedimentation environment. In this study, we analyzed them by several methods and grasped the bottom environment of both areas after the removal of dikes. We examined the impact of the restoration to both areas by comparing the observations with the past data. Surface sediment samples in Lake Nakaumi and Honjo Area were obtained at 77 and 40 stations, respectively. We collected surface sediment (about 1cm) were for each station, and analyzed total organic carbon (TOC) and total nitrogen (TN) as organic matter, and hydrogen sulfide (H2S) in pore water, total sulfide (TS) and acid volatile sulfide (AVS) as sulfides. TOC contents of Lake Nakaumi and Honjo Area range within 0.0-5.1% and 0.2-4.9%, respectively. TN contents range within 0.0-0.6 % and 0.1-0.6 %. TS contents range within 0.1-2.6% and 0.0-2.0 %. H2S contents range within 0.3-119.0 ppm and 0.5-140.4 ppm. AVS contents range within 0

  8. Lake levels, streamflow, and surface-water quality in the Devils Lake area, North Dakota

    USGS Publications Warehouse

    Wiche, Gregg J.

    1996-01-01

    The Devils Lake Basin is a 3,810-square-mile (mi2) closed basin (fig. 1) in the Red River of the North Basin. About 3,320 mi2 of the total 3,810 mi2 is tributary to Devils Lake; the remainder is tributary to Stump Lake.Since glaciation, the lake level of Devils Lake has fluctuated from about 1,457 feet (ft) above sea level (asl), the natural spill elevation of the lake to the Sheyenne River, to 1,400 ft asl (Aronow, 1957). Although no documented records of lake levels are available before 1867, Upham (1895, p. 595), on the basis of tree-ring chronology, indicated that the lake level was 1,441 ft asl in 1830. Lake levels were recorded sporadically from 1867 to 1901 when the U.S. Geological Survey established a gaging station on Devils Lake. From 1867 to the present (1996), the lake level has fluctuated between a maximum of 1,438.4 ft asl in 1867 and a minimum of 1,400.9 ft asl in 1940 (fig. 2). On July 31, 1996, the lake level was 1,437.8 ft asl, about 15.2 ft higher than the level recorded in February 1993 and the highest level in about 120 years.Since 1993, the lake level of Devils Lake (fig. 2) has risen rapidly in response to above-normal precipitation from the summer of 1993 to the present, and 30,000 acres of land around the lake have been flooded. The above-normal precipitation also has caused flooding elsewhere in the Devils Lake Basin. State highways near Devils Lake are being raised, and some local roads have been closed because of flooding.In response to the flooding, the Devils Lake Basin Interagency Task Force, comprised of many State and Federal agencies, was formed in 1995 to find and propose intermediate (5 years or less) solutions to reduce the effects of high lake levels. In addition to various planning studies being conducted by Federal agencies, the North Dakota State Water Commission has implemented a project to store water on small tracts of land and in the chain of lakes (Sweetwater Lake, Morrison Lake, Dry Lake, Mikes Lake, Chain Lake

  9. Execution of deep dipole geoelectrical soundings in areas of geothermal interest. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patella, D.

    It is suggested that deep geoelectrical problems may be resolved by carrying out dipole soundings in the field and applying a quantitative interpretation in the Schlumberger domain. The 'transformation' of original field dipole sounding curves into equivalent Schlumberger curves is outlined for the cases of layered structures and arbitrary underground structures. Theoretical apparent resistivity curves are derived for soundings over bidimensional structures. Following a summary of the geological features of the Travale-Radicondoli geothermal area of Italy, the dipole sounding method employed for this field study and the means of collecting and analyzing the data, are outlined.

  10. Quaternary geology of the Boston area: Glacial events from Lake Charles to Lake Aberjona

    USGS Publications Warehouse

    Stone, Byron D.; Lane, John W.

    2014-01-01

    The multiple-glacial and glaciomarine Quaternary history of the Boston, Massachusetts area has been known generally since the earliest studies of the then newly recognized glacial deposits described by Prof. Louis Agassiz in the late1840’s and fossil marine shells in the drift in the 1850’s. Attention then turned to possible glacial erosional effects on the preglacial bedrock physiography, as related to rock units and structure, and to the challenges of defining useful physical and lithic characteristics of the drift by Prof. W.O. Crosby and others, 1880-1900. The problems of deducing the relative stratigraphic order among such small, fossil-barren surficial sedimentary deposits, and extending knowledge gained from studies of postulated ancient glacial lakes to a regional understanding of the history of many lakes during the retreat of the ice sheet required field work and use of geologic maps. With the advent of modern topographic maps in the 1880’s, the early period of discovery included field studies of glacial lake deposits in local river basins in the Boston region, basins that drain northward, thereby creating glacial lake basins dammed by the ice margin as it retreated to the north. Guided by M.I.T. and Harvard professors W.O. Crosby, N.S. Shaler, J.B. Woodworth, W.M. Davis, and others in the 1880-1920 period, the first Quaternary glacial stratigraphers were students (e.g. Crosby and Grabau, 1896, Clapp, 1905, Fuller 1905, Goldthwaite 1906, Grabau, 1906, Taylor, Tight).

  11. Geothermal direct use in the United States update: 1990-1994

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lienau, P.J.; Lund, J.W.; Culver, G.G.

    1995-02-01

    Geothermal energy is estimated to currently supply approximately 13,885 TJ/yr (13,180 x 10{sup 9} BTU/yr) of heat energy through direct heat applications in the United States. Table 1 summarizes the U.S. geothermal direct heat uses. It should be noted that Table 1 does not contain enhanced oil recovery, which was included in the 1990 update report. In the oil fields of the upper midwest (Montana, North Dakota and Wyoming), thermal waters are not being injected at higher temperatures than the oil producing zones. This means that there is no benefit to reducing oil viscosity, which would have increased production rates;more » therefore, resulting in this use being deleted from direct uses in the table. In the 1990 report two geothermal district heating systems were listed as under construction, Mammoth Lakes and Bridgeport, these systems have not been built although exploratory wells have been drilled. They are not included in the current summary of direct uses. There have been no new geothermal district heating systems started; however, San Bernardino and Klamath Falls have expanded their systems. Annual energy use of direct heat applications reported for both the 1990 and 1994 updates are shown. All of the categories experienced some increase in use, however the largest growth has been in geothermal heat pumps. From 1985 to 1990 the highest growth rate in geothermal heat pumps occurred, then tapered off some from 1990 to 1994. In the other five categories there has been a steady growth with the largest occurring in space heating, greenhouses and industrial plants. Greenhouse development has been significant in New Mexico and Utah and a new onion and garlic dehydration plant was built in Nevada.« less

  12. Geologic map database of the El Mirage Lake area, San Bernardino and Los Angeles Counties, California

    USGS Publications Warehouse

    Miller, David M.; Bedford, David R.

    2000-01-01

    This geologic map database for the El Mirage Lake area describes geologic materials for the dry lake, parts of the adjacent Shadow Mountains and Adobe Mountain, and much of the piedmont extending south from the lake upward toward the San Gabriel Mountains. This area lies within the western Mojave Desert of San Bernardino and Los Angeles Counties, southeastern California. The area is traversed by a few paved highways that service the community of El Mirage, and by numerous dirt roads that lead to outlying properties. An off-highway vehicle area established by the Bureau of Land Management encompasses the dry lake and much of the land north and east of the lake. The physiography of the area consists of the dry lake, flanking mud and sand flats and alluvial piedmonts, and a few sharp craggy mountains. This digital geologic map database, intended for use at 1:24,000-scale, describes and portrays the rock units and surficial deposits of the El Mirage Lake area. The map database was prepared to aid in a water-resource assessment of the area by providing surface geologic information with which deepergroundwater-bearing units may be understood. The area mapped covers the Shadow Mountains SE and parts of the Shadow Mountains, Adobe Mountain, and El Mirage 7.5-minute quadrangles. The map includes detailed geology of surface and bedrock deposits, which represent a significant update from previous bedrock geologic maps by Dibblee (1960) and Troxel and Gunderson (1970), and the surficial geologic map of Ponti and Burke (1980); it incorporates a fringe of the detailed bedrock mapping in the Shadow Mountains by Martin (1992). The map data were assembled as a digital database using ARC/INFO to enable wider applications than traditional paper-product geologic maps and to provide for efficient meshing with other digital data bases prepared by the U.S. Geological Survey's Southern California Areal Mapping Project.

  13. RiverHeath: Neighborhood Loop Geothermal Exchange System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Geall, Mark

    2016-07-11

    The goal of the RiverHeath project is to develop a geothermal exchange system at lower capital infrastructure cost than current geothermal exchange systems. The RiverHeath system features an innovative design that incorporates use of the adjacent river through river-based heat exchange plates. The flowing water provides a tremendous amount of heat transfer. As a result, the installation cost of this geothermal exchange system is lower than more traditional vertical bore systems. Many urban areas are located along rivers and other waterways. RiverHeath will serve as a template for other projects adjacent to the water.

  14. Guidance for Delisting Michigan’s Great Lakes Areas of Concern

    EPA Pesticide Factsheets

    A useful tool for guidance in delisting Michigan’s Areas of Concern. Technical staff in the Michigan Department of Environmental Quality (MDEQ), the Michigan Department of Natural Resources (MDNR), USEPA Great Lakes National Program Office, among others.

  15. Geothermal direct-heat utilization assistance. Quarterly report, January - March 1997

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lienau, P.

    1997-04-01

    This report summarizes geothermal technical assistance, R&D and technology transfer activities of the Geo-Heat Center at Oregon Institute of Technology for the second quarter of FY-97. It describes 176 contacts with parties during this period related to technical assistance with geothermal direct heat projects. Areas dealt with include geothermal heat pumps, space heating, greenhouses, aquaculture, equipment, economics and resources. Research activities are summarized on well pumping in commercial groundwater heat pump systems. A memorandum of understanding between the GHC and EIA is described. Work accomplishments on the Guidebook are discussed. Outreach activities include the publication of a geothermal direct usemore » Bulletin, dissemination of information, geothermal library, technical papers and seminars, and progress monitor reports on geothermal resources and utilization.« less

  16. Geohydrologic reconnaissance of Lake Mead National Recreation Area; Las Vegas Wash to Opal Mountain, Nevada

    USGS Publications Warehouse

    Laney, R.L.

    1981-01-01

    The study is a geohydrologic reconnaissance of about 170 square miles in the Lake Mead National Recreation Area from Las Vegas Wash to Opal Mountain, Nevada. The study is one of a series that describes the geohydrology of the recreation area and that indentifies areas where water supplies can be developed. Precipitation in this arid area is about 5 inches per year. Streamflow is seasonal and extremely variable except for that in the Colorado River, which adjoins the area. Pan evaporation is more than 20 times greater than precipitation; therefore, regional ground-water supplies are meager except near the Colorado River, Lake Mead, and Lake Mohave. Large ground-water supplies can be developed near the river and lakes, and much smaller supplies may be obtained in a few favorable locations farther from the river and lakes. Ground water in most of the areas probably contains more than 1,000 milligrams per liter of dissolved solids, but water that contains less than 1,000 milligrams per liter of dissolved solids can be obtained within about 1 mile of the lakes. Crystalline rocks of metamorphic, intrusive and volcanic origin crop out in the area. These rocks are overlain by conglomerate and mudstone of the Muddy Creek Formation, gravel and conglomerate of the older alluvium, and sand and gravel of the Chemehuevi Formation and younger alluvium. The crystalline rocks, where sufficiently fractured, yield water to springs and would yield small amounts of water to favorably located wells. The poorly cemented and more permeable beds of the older alluvium, Chemehuevi Formation, and younger alluvium are the better potential aquifers, particularly along the Colorado River and Lakes Mead and Mohave. Thermal springs in the gorge of the Colorado River south of Hoover Dam discharge at least 2,580 acre-feet per year of water from the volcanic rocks and metamorphic and plutonic rocks. The discharge is much greater than could be infiltrated in the drainage basin above the springs

  17. Geothermal systems

    NASA Technical Reports Server (NTRS)

    Mohl, C.

    1978-01-01

    Several tasks of JPL related to geothermal energy are discussed. The major task is the procurement and test and evaluation of a helical screw drive (wellhead unit). A general review of geothermal energy systems is given. The presentation focuses attention on geothermal reservoirs in California, with graphs and charts to support the discussion. Included are discussions on cost analysis, systems maintenance, and a comparison of geothermal and conventional heating and cooling systems.

  18. Slip and Dilation Tendency Analysis of the Patua Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes

  19. Geothermal Program Review IV: proceedings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1985-01-01

    The research and development program of DOE's Geothermal Technology Division is reviewed in separate presentations according to program area. Separate abstracts have been prepared for the individual papers. (ACR)

  20. Geothermal Money Book [Geothermal Outreach and Project Financing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Elizabeth Battocletti

    2004-02-01

    Small business lending is big business and growing. Loans under $1 million totaled $460 billion in June 2001, up $23 billion from 2000. The number of loans under $100,000 continued to grow at a rapid rate, growing by 10.1%. The dollar value of loans under $100,000 increased 4.4%; those of $100,000-$250,000 by 4.1%; and those between $250,000 and $1 million by 6.4%. But getting a loan can be difficult if a business owner does not know how to find small business-friendly lenders, how to best approach them, and the specific criteria they use to evaluate a loan application. This ismore » where the Geothermal Money Book comes in. Once a business and financing plan and financial proposal are written, the Geothermal Money Book takes the next step, helping small geothermal businesses locate and obtain financing. The Geothermal Money Book will: Explain the specific criteria potential financing sources use to evaluate a proposal for debt financing; Describe the Small Business Administration's (SBA) programs to promote lending to small businesses; List specific small-business friendly lenders for small geothermal businesses, including those which participate in SBA programs; Identify federal and state incentives which are relevant to direct use and small-scale (< 1 megawatt) power generation geothermal projects; and Provide an extensive state directory of financing sources and state financial incentives for the 19 states involved in the GeoPowering the West (GPW). GPW is a U.S. Department of Energy-sponsored activity to dramatically increase the use of geothermal energy in the western United States by promoting environmentally compatible heat and power, along with industrial growth and economic development. The Geothermal Money Book will not: Substitute for financial advice; Overcome the high exploration, development, and financing costs associated with smaller geothermal projects; Remedy the lack of financing for the exploration stage of a geothermal project; or Solve

  1. Recreation Carrying Capacity Facts and Considerations. Report 2. Benbrook Lake Project Area.

    DTIC Science & Technology

    1980-07-01

    Lake and the representa- tives from the Fort Worth District Office. Their contributions of practical experi- ence and knowledge , along with their...Acceptability of techniques - Table 8 indicates the acceptability of different techniques for solving problems to the boaters and water- skiers surveyed at...boats near swimming areas. Boater/water- Boaters, especially jet e consider lake zoning, e.g. restrict skier conflicts boaters, are sometimes waterskiing

  2. Deep Geothermal Energy for Lower Saxony (North Germany) - Combined Investigations of Geothermal Reservoir Characteristics

    NASA Astrophysics Data System (ADS)

    Hahne, Barbara; Thomas, Rüdiger

    2014-05-01

    In Germany, successful deep geothermal projects are mainly situated in Southern Germany in the Molassebecken, furthermore in the Upper Rhine Graben and, to a minor extend, in the North German Basin. Mostly they are hydrothermal projects with the aim of heat production. In a few cases, they are also constructed for the generation of electricity. In the North German Basin temperature gradients are moderate. Therefore, deep drilling of several thousand meters is necessary to reach temperatures high enough for electricity production. However, the porosity of the sedimentary rocks is not sufficient for hydrothermal projects, so that natural fracture zones have to be used or the rocks must be hydraulically stimulated. In order to make deep geothermal projects in Lower Saxony (Northern Germany) economically more attractive, the interdisciplinary research program "Geothermal Energy and High-Performance Drilling" (gebo) was initiated in 2009. It comprises four focus areas: Geosystem, Drilling Technology, Materials and Technical System and aims at improving exploration of the geothermal reservoir, reducing costs of drilling and optimizing exploitation. Here we want to give an overview of results of the focus area "Geosystem" which investigates geological, geophysical, geochemical and modeling aspects of the geothermal reservoir. Geological and rock mechanical investigations in quarrys and core samples give a comprehensive overview on rock properties and fracture zone characteristics in sandstones and carbonates. We also show that it is possible to transfer results of rock property measurements from quarry samples to core samples or to in situ conditions by use of empirical relations. Geophysical prospecting methods were tested near the surface in a North German Graben system. We aim at transferring the results to the prospection of deep situated fracture zones. The comparison of P- and S-wave measurements shows that we can get hints on a possible fluid content of the

  3. Geothermal Coproduction and Hybrid Systems | Geothermal Technologies | NREL

    Science.gov Websites

    systems. Geothermal and Oil and Gas NREL experts are working to find ways to effectively use renewable resources in combination with fossil energy. Geothermal and oil and gas hybrid systems make use of wells already drilled by oil and gas developers. Using coproduced geothermal fluids for power production from

  4. BEHAVIOR OF ARSENIC AND OTHER REDOX-SENSITIVE ELEMENTS IN CROWLEY LAKE, CA: A RESERVOIR IN THE LOS ANGELES AQUEDUCT SYSTEM. (R826202)

    EPA Science Inventory

    Elevated arsenic concentrations in Crowley Lake derive from upstream geothermal inputs. We examined the water column of Crowley Lake under stratified and unstratified conditions, seeking evidence for algal uptake and transformation of arsenic and its deposition to and release fro...

  5. Halophilic Archaea determined from geothermal steam vent aerosols.

    PubMed

    Ellis, Dean G; Bizzoco, Richard W; Kelley, Scott T

    2008-06-01

    Hydrothermal vents, known as 'fumaroles', are ubiquitous features of geothermal areas. Although their geology has been extensively characterized, little is known about the subsurface microbial ecology of fumaroles largely because of the difficulty in collecting sufficient numbers of cells from boiling steam water for DNA extraction and culture isolation. Here we describe the first collection, molecular analysis and isolation of microbes from fumarole steam waters in Russia (Kamchatka) and the USA (Hawaii, New Mexico, California and Wyoming). Surprisingly, the steam vent waters from all the fumaroles contained halophilic Archaea closely related to the Haloarcula spp. found in non-geothermal salt mats, saline soils, brine pools and salt lakes around the world. Microscopic cell counting estimated the cell dispersal rate at approximately 1.6 x 10(9) cells year(-1) from a single fumarole. We also managed to enrich microbes in high-salt media from every vent sample, and to isolate Haloarcula from a Yellowstone vent in a 20% salt medium after a month-long incubation, demonstrating both salt tolerance and viability of cells collected from high-temperature steam. Laboratory tests determined that microbes enriched in salt media survived temperatures greater than 75 degrees C for between 5 and 30 min during the collection process. Hawaiian fumaroles proved to contain the greatest diversity of halophilic Archaea with four new lineages that may belong to uncultured haloarchaeal genera. This high diversity may have resulted from the leaching of salts and minerals through the highly porous volcanic rock, creating a chemically complex saline subsurface.

  6. Surficial geologic map of the Red Rock Lakes area, southwest Montana

    USGS Publications Warehouse

    Pierce, Kenneth L.; Chesley-Preston, Tara L.; Sojda, Richard L.

    2014-01-01

    The Centennial Valley and Centennial Range continue to be formed by ongoing displacement on the Centennial fault. The dominant fault movement is downward, creating space in the valley for lakes and the deposition of sediment. The Centennial Valley originally drained to the northeast through a canyon now represented by a chain of lakes starting with Elk Lake. Subsequently, large landslides blocked and dammed the drainage, which created Lake Centennial, in the Centennial Valley. Sediments deposited in this late Pleistocene lake underlie much of the valley floor and rest on permeable sand and gravel deposited when the valley drained to the northeast. Cold Pleistocene climates enhanced colluvial supply of gravelly sediment to mountain streams and high peak flows carried gravelly sediment into the valley. There, the lower gradient of the streams resulted in deposition of alluvial fans peripheral to Lake Centennial as the lake lowered through time to the level of the two present lakes. Pleistocene glaciers formed in the high Centennial Range, built glacial moraines, and also supplied glacial outwash to the alluvial fans. Winds from the west and south blew sand to the northeast side of the valley building up high dunes. The central part of the map area is flat, sloping to the west by only 0.6 meters in 13 kilometers (2 feet in 8 miles) to form a watery lowland. This lowland contains Upper and Lower Red Rock Lakes, many ponds, and peat lands inside the “water plane,” above which are somewhat steeper slopes. The permeable sands and gravels beneath Lake Centennial sediments provide a path for groundwater recharged from the adjacent uplands. This groundwater leaks upward through Lake Centennial sediments and sustains wetland vegetation into late summer. Upper and Lower Red Rock Lakes are formed by alluvial-fan dams. Alluvial fans converge from both the south and the north to form outlet thresholds that dam the two shallow lakes upstream. The surficial geology aids in

  7. Geothermal Energy.

    ERIC Educational Resources Information Center

    Bufe, Charles Glenn

    1983-01-01

    Major activities, programs, and conferences in geothermal energy during 1982 are highlighted. These include first comprehensive national assessment of U.S. low-temperature geothermal resources (conducted by U.S. Geological Survey and Department of Energy), map production by U.S. Geological Survey, geothermal plant production, and others. (JN)

  8. Increasing Efficiency by Maximizing Electrical Output

    DTIC Science & Technology

    2016-08-01

    to electricity technology in a few limited areas, one being a geothermal flash plant at Naval Air Weapons Station China Lake. But, there are few...generation c) Increasing the efficiency of portable generators to reduce fuel needs. d) Bottom cycling on a geothermal flash plant like the one at Naval...portable generators to reduce fuel needs. d) Bottom cycling on a geothermal flash plant like the one at Naval Air Weapons Station China Lake

  9. Multi-usages of the Ilan geothermal field, NE Taiwan

    NASA Astrophysics Data System (ADS)

    Lee, C. S.; Tseng, P.; Wang, S.; Chang, C.

    2017-12-01

    The tectonics of Taiwan is very dynamic. The area produces more than 30,000 earthquakes/year; the mountains uplift 4-5 cm/year; the rainfall culminates 3,000 mm/year; there are some 4,000 hot spring operators. One of the two hot geothermal areas is located in NE Taiwan - the Ilan geothermal field. In order to develop the geothermal energy for the electricity need, the Ministry of Science and Technology have provided the fund to drill two 2,500 deep wells. The results are not so encourage for the need of an Enhanced Geothermal System. However, one of the wells has a bottom temperature of 160oC and the water up loading with 60 ton/hr. This can be combined with the near-by wells drilled by the private drilling company and the Cardinal Tien Junior College of Healthcare and Management to develop the multi-usages of the geothermal energy, such as 1 MW of electricity for the college and village, the long-term healthcare and hot spring medicare, aquaculture and agriculture need etc. The universities and private drilling company cooperate together to join the development. Hope this will provide a new model for the need of a self-sufficient community. The geothermal is a clean, renewable, and no pollution energy. Taiwan is in an initial stage of using this green energy.

  10. Crystalline rocks of the Strawberry Lake area, Front Range, Colorado

    USGS Publications Warehouse

    Young, Edward J.

    1991-01-01

    This report is a petrographic and geochemical study of the bedrock and a petrologic discussion based on felsic-mafic and silica-saturation ratios of the Strawberry Lake area. This volume is published as chapters A and B. These chapters are not available separatelyThe Strawberry lake area lies between the Continental Divide and Granby, Colorado, just north of Tabernash. It is underlain by Proterozoic rocks composed of biotite gneiss and two plutons-Boulder Creek Granodiorite of the Routt Plutonic Suite and Silver Plume Granite of the Berthoud Plutonic Suite. Relict enclaves of biotite gneiss are not uncommon in the Boulder Creek Granodiorite, in the Silver Plume Granite, and in the granitic enclaves in the biotite gneiss. Granitic and mafic enclaves in the Boulder Creek Granodiorite, granitic enclaves in the Silver Plume Granite and in the biotite gneiss, and a Tertiary andesite porphyry dike complete the rock types.

  11. Modeling and Simulation of the Gonghe geothermal field (Qinghai, China) Constrained by Geophysical

    NASA Astrophysics Data System (ADS)

    Zeng, Z.; Wang, K.; Zhao, X.; Huai, N.; He, R.

    2017-12-01

    The Gonghe geothermal field in Qinghai is important because of its variety of geothermal resource types. Now, the Gonghe geothermal field has been a demonstration area of geothermal development and utilization in China. It has been the topic of numerous geophysical investigations conducted to determine the depth to and the nature of the heat source, and to image the channel of heat flow. This work focuses on the causes of geothermal fields used numerical simulation method constrained by geophysical data. At first, by analyzing and inverting an magnetotelluric (MT) measurements profile across this area we obtain the deep resistivity distribution. Using the gravity anomaly inversion constrained by the resistivity profile, the density of the basins and the underlying rocks can be calculated. Combined with the measured parameters of rock thermal conductivity, the 2D geothermal conceptual model of Gonghe area is constructed. Then, the unstructured finite element method is used to simulate the heat conduction equation and the geothermal field. Results of this model were calibrated with temperature data for the observation well. A good match was achieved between the measured values and the model's predicted values. At last, geothermal gradient and heat flow distribution of this model are calculated(fig.1.). According to the results of geophysical exploration, there is a low resistance and low density region (d5) below the geothermal field. We recognize that this anomaly is generated by tectonic motion, and this tectonic movement creates a mantle-derived heat upstream channel. So that the anomalous basement heat flow values are higher than in other regions. The model's predicted values simulated using that boundary condition has a good match with the measured values. The simulated heat flow values show that the mantle-derived heat flow migrates through the boundary of the low-resistance low-density anomaly area to the Gonghe geothermal field, with only a small fraction

  12. Study on the relationship between the lake area variations of Qinghai-Tibetan Plateau and the corresponding climate change in their basins

    NASA Astrophysics Data System (ADS)

    Guozhuang, Shen; Jingjuan, Liao; Huadong, Guo; Yingkui, Li

    2014-03-01

    Qinghai-Tibetan Plateau is the largest lake area in China, with a total area of existing lakes of 36,900km2, accounting for 52% of the total lake area of China. Lakes on the Tibetan Plateau play critical roles in the water cycle and ecological and environment systems of the Plateau. The global trend of warming up is increasing obviously, which has led to major changes in the climate conditions in China, even in the world. Whereas, when they analyse the relationship they just use the weather station's recording data, without any spatial analysis of the climate data. Here, we will do some researches on the relationship between the 10 selected lakes' area variation and the corresponding climate change in their drainage basin and discuss how the lakes changes in recent 40 years using the climate data processed using the spatial kriging. Thus, the drainage area can be taken into account and a real relationship can be pointed out. In order to study the relationship, Landsat MSS data, Landsat TM, Landsat ETM images, the topographic map have been collected to extract the variation of lake area. The 131 weather stations climate data, including precipitation, temperature, sun shine duration, evaporation are chosen to study the relationship. After extraction of the area of the lakes, a multivariate statistical analysis method was used to test the relationship between the area of the lakes and the global climate change, including the change of the temperature, the precipitation, and other factors. The variation of lakes in Qinghai-Tibetan Plateau is related to the mean temperature, the precipitation and saturation vapour pressure. But the frozen soil may affect the lake area variation to some extent.

  13. Using geothermal energy to heat a portion of a formation for an in situ heat treatment process

    DOEpatents

    Pieterson, Roelof; Boyles, Joseph Michael; Diebold, Peter Ulrich

    2010-06-08

    Methods of using geothermal energy to treat subsurface formations are described herein. Methods for using geothermal energy to treat a subsurface treatment area containing or proximate to hydrocarbons may include producing geothermally heated fluid from at least one subsurface region. Heat from at least a portion of the geothermally heated fluid may be transferred to the subsurface treatment area to heat the subsurface treatment area. At least some hydrocarbon fluids may be produced from the formation.

  14. Cancer mortality and other causes of death in users of geothermal hot water.

    PubMed

    Kristbjornsdottir, Adalbjorg; Rafnsson, Vilhjalmur

    2015-01-01

    Residents of geothermal areas have increased incidence of non-Hodgkin's lymphoma, breast, prostate, and kidney cancers. The aim was to study whether this is also reflected in cancer mortality among the population using geothermal hot water for space heating, washing, and showering. The follow-up was from 1981 to 2009. Personal identifier of those 5-64 years of age was used in record linkage with nationwide death registry. Thus, vital and emigration status was ascertained. The exposed population was defined as inhabitants of communities with district heating generated from geothermal wells since 1972. Reference populations were inhabitants of other areas with different degrees of volcanic/geothermal activity. Hazard ratio (HR) and 95% confidence intervals (CI) were adjusted for age, gender, education, housing, reproductive factors and smoking habits. Among those using geothermal water, the HR for all causes of death was 0.98 (95% CI 0.91-1.05) as compared with cold reference area. The HR for breast cancer was 1.53 (1.04-2.24), prostate cancer 1.74 (1.21-2.52), kidney cancer 1.78 (1.03-3.07), and for non-Hodgkin's lymphoma 2.01 (1.05-3.38). HR for influenza was 3.36 (1.32-8.58) and for suicide 1.49 (1.03-2.17). The significant excess mortality risk of breast and prostate cancers, and non-Hodgkin's lymphoma confirmed the results of similarly designed studies in Iceland on cancer incidence among populations from high-temperature geothermal areas and users of geothermal hot water. The risk is not confined to cancers with good prognosis, but also concerns fatal cancers. Further studies are needed on the chemical and physical content of the water and the environment emissions in geothermal areas.

  15. Geology and Conceptual Model of the Domuyo Geothermal Area, Patagonia, Argentina

    NASA Astrophysics Data System (ADS)

    Fragoso, A. S.; Ferrari, L.; Norini, G.

    2017-12-01

    Cerro Domuyo is the highest mountain in Patagonia and its western slope is characterized by thermal springs with boiling fluids as well as silicic domes and pyroclastic deposits that suggest the existence of a geothermal reservoir. Early studies proposed that the thermal springs were fault-controlled and the reservoir was located in a graben bounded by E-W normal faults. A recent geochemical study estimated a temperature of 220ºC for the fluid reservoir and a thermal energy release of 1.1 GW, one of the world largest advective heat flux from a continental volcanic center. We carried out a geologic survey and U-Pb and U-Th geochronologic study to elaborate an updated conceptual model for the Domuyo geothermal area. Our study indicates that the Domuyo Volcanic Complex (DVC) is a dome complex overlying an older, Middle Miocene to Pliocene volcanic sequence widely exposed to the southwest and to the north, which in turn covers: 1) the Jurassice-Early Creteacoeus Neuquen marine sedimentary succession, 2) silicic ignimbrites dated at 186.7 Ma and, 3) the Paleozoic metamorphic basement intruded by 288 Ma granite bodies. These pre-Cenozoic successions are involved in dominantly N-S trending folds and thrust faults later displaced by E-W striking normal faults with a right lateral component of motion that underlie the DVC. The volcanic cycle forming the DVC is distinctly bimodal with the emplacement of massive silicic domes but also less voluminous olivine basalts on its southern slope. The central dome underwent a major collapse that produced 0.35 km3 of ash and block flow and associated pyroclastic flows that filled the valley to the southwest up to 30 km from the source. This was followed by a voluminous effusive activity that formed silicic domes dated between 254-322 Ky, which is inferred to overlain a partially molten silicic magma chamber. Integrating the geologic model with magnetotelluric and gravity surveys we developed a conceptual model of the geothermal system

  16. Direct utilization of geothermal energy in the Peoples Republic of China

    NASA Astrophysics Data System (ADS)

    Lund, J. W.

    1980-12-01

    A brief review of the direct utilization of geothermal energy in three regions of the Peoples' Republic of China is presented, stressing a development outline for the next five to ten years. The geothermal resource of the Tianjin-Beijing area is mainly to be developed for space heating, whereas along the coastal area of Fujian and Guangdong, it will be developed for agriculture, and industrial and residential use. Electric power generation will be the main concern in the southwest at Tengchong. Most theoretical research will be done on geologic structure interpretation, corrosion of pump shafts and buried pipelines, and heat flow, with some interest in the study of geopressure and hot dry rock systems. Specific examples from the Tianjin area include a wool factory; a wool rug weaving shop; heating of a hotel; public bathing; and well drilling for apartment heating, fish breeding, and greenhouses. Direct use of geothermal energy in the Beijing area includes cotton dyeing, humidifying, medical purposes, and animal husbandry. Experimental geothermal electric power plants are summarized in table form.

  17. Calculation of area and volume for the south part of Great Salt Lake, Utah

    USGS Publications Warehouse

    Baskin, Robert L.

    2005-01-01

    The U.S. Geological Survey, in cooperation with the Utah Department of Natural Resources, Division of Wildlife Resources, collected bathymetric data for the south part of Great Salt Lake during 2002-04 using a single-beam, high-definition fathometer and real-time differential global positioning system. About 7.6 million depth measurements were collected along more than 930 miles (1,690 kilometers) of survey transects. Sound-velocity profiles were obtained in conjunction with the bathymetric data to provide time-of-travel corrections to the depth calculations. Data were processed with commercial hydrographic software and exported into geographic information system (GIS) software for mapping and calculation of area and volume. Area and volume calculations show a maximum area of about 508,000 acres (2,056 square kilometers) and a maximum volume of about 9,257,000 acre-feet (11.42 cubic kilometers) at a water-surface altitude of 4,200 feet (1,280 meters). Minimum water-surface altitude of the south part of Great Salt Lake is just below 4,167 feet (1,279 meters) in the area just south of the Union Pacific railroad causeway halfway between Promontory Point and the western edge of the lake. At this altitude, and continuing up to about 4,176 feet (1,279 meters), the south part of the lake is separated into two areas by a ridge extending from Promontory Point to Hat Island. Calculations for area and volume are based on a low altitude of 4,167 feet (1,279 meters) to a high altitude of 4,200 feet (1,280 meters).

  18. Snohomish County Public Utility District Geothermal Energy Exploration Study Final Technical Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lewis, Adam; Collar, Craig W.

    2012-10-04

    Supported by funds from this award, the District thoroughly explored the feasibility of a hydrothermal geothermal development within its service territory. The District successfully planned and drilled six exploratory geothermal wells and added significantly to the knowledge of the geology of the area. The Straight Creek Fault region, which was the sole location that showed significant potential for hydrothermal development in the District's service territory, was determined not to be feasible for development. The District subsequently expanded its search for geothermal development locations to include all of Washington State. Mount Baker has been identified as the area of the statemore » with the greatest potential for geothermal development. Having gathered additional information about the Mount Baker region with support from this award, the District is actively pursuing exploration and development in the area.« less

  19. Geothermal Impact Analysis | Geothermal Technologies | NREL

    Science.gov Websites

    on potential geothermal growth scenarios, jobs and economic impacts, clean energy manufacturing geothermal resources. We: Perform resource analysis Develop techno-economic models Quantify environmental growth scenarios across multiple market sectors. Learn more about the GeoVision Study. Jobs and Economic

  20. 36 CFR 7.48 - Lake Mead National Recreation Area.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Lake Mead National Recreation Area. 7.48 Section 7.48 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... watercraft at a speed in excess of flat wake speed within 200 feet of any beach occupied by bathers, boats at...

  1. 36 CFR 7.48 - Lake Mead National Recreation Area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Lake Mead National Recreation Area. 7.48 Section 7.48 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... watercraft at a speed in excess of flat wake speed within 200 feet of any beach occupied by bathers, boats at...

  2. 36 CFR 7.48 - Lake Mead National Recreation Area.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Lake Mead National Recreation Area. 7.48 Section 7.48 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... watercraft at a speed in excess of flat wake speed within 200 feet of any beach occupied by bathers, boats at...

  3. 36 CFR 7.48 - Lake Mead National Recreation Area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Lake Mead National Recreation Area. 7.48 Section 7.48 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... watercraft at a speed in excess of flat wake speed within 200 feet of any beach occupied by bathers, boats at...

  4. 36 CFR 7.48 - Lake Mead National Recreation Area.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Lake Mead National Recreation Area. 7.48 Section 7.48 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... watercraft at a speed in excess of flat wake speed within 200 feet of any beach occupied by bathers, boats at...

  5. New geochemical investigations in Platanares and Azacualpa geothermal sites (Honduras)

    NASA Astrophysics Data System (ADS)

    Barberi, Franco; Carapezza, Maria Luisa; Cioni, Roberto; Lelli, Matteo; Menichini, Matia; Ranaldi, Massimo; Ricci, Tullio; Tarchini, Luca

    2013-05-01

    Platanares and Azacualpa geothermal sites of Honduras are located in an inner part of the Caribbean Plate far from the active volcanic front of Central America. Here geology indicates that there are not the conditions for the occurrence of shallow magmatic heat sources for high-enthalpy geothermal resources. Geothermal perspectives are related to the possibility of a deep circulation of meteoric water along faults and the storage of the heated fluid in fractured permeable reservoirs. Geochemical geothermometers indicate a temperature for the deeper part of the geothermal reservoir close to 200 °C for Platanares and of 150-170 °C for Azacualpa. Calcite scaling, with subordinate silica deposition has to be expected in both sites. CO2 soil flux investigations have been carried out in both areas and reveal the presence of positive anomalies likely corresponding to the presence at depth of fractured degassing geothermal reservoirs. Compared with the geothermal areas of Central Italy whose reservoirs are hosted in carbonate rocks, e.g. Latera (Chiodini et al., 2007), the CO2 soil flux measured in Honduras is significantly lower (mean of 17 g/m2day at Platanares and of 163 g/m2day at Azacualpa) probably because of the dominant silicate nature of the deep reservoirs.

  6. 3D Model of the McGinness Hills Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    The McGinness Hills geothermal system lies in a ~8.5 km wide, north-northeast trending accommodation zone defined by east-dipping normal faults bounding the Toiyabe Range to the west and west-dipping normal faults bounding the Simpson Park Mountains to the east. Within this broad accommodation zone lies a fault step-over defined by north-northeast striking, west-dipping normal faults which step to the left at roughly the latitude of the McGinness Hills geothermal system. The McGinness Hills 3D model consists of 9 geologic units and 41 faults. The basal geologic units are metasediments of the Ordovician Valmy and Vininni Formations (undifferentiated in the model) which are intruded by Jurassic granitic rocks. Unconformably overlying is a ~100s m-thick section of Tertiary andesitic lava flows and four Oligocene-to-Miocene ash-flow tuffs: The Rattlesnake Canyon Tuff, tuff of Sutcliffe, the Cambell Creek Tuff and the Nine Hill tuff. Overlying are sequences of pre-to-syn-extensional Quaternary alluvium and post-extensional Quaternary alluvium. 10-15º eastward dip of the Tertiary stratigraphy is controlled by the predominant west-dipping fault set. Geothermal production comes from two west dipping normal faults in the northern limb of the step over. Injection is into west dipping faults in the southern limb of the step over. Production and injection sites are in hydrologic communication, but at a deep level, as the northwest striking fault that links the southern and northern limbs of the step-over has no permeability.

  7. Deep electrical investigations in the Long Valley geothermal area, California

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stanley, W.D.; Jackson, D.B.; Zohdy, A.A.R.

    1976-02-10

    Direct current resistivity and time domain electromagnetic techniques were used to study the electrical structure of the Long Valley geothermal area. A resistivity map was compiled from 375 total field resistivity measurements. Two significant zones of low resistivity were detected, one near Casa Diablo Hot Springs and one surrounding the Cashbaugh Ranch-Whitmore Hot Springs area. These anomalies and other parts of the caldera were investigated in detail with 49 Schlumberger dc soundings and 13 transient electromagnetic soundings. An extensive conductive zone of 1- to 10-..cap omega..m resistivity was found to be the cause of the total field resistivity lows. Drillmore » hole information indicates that the shallow parts of the conductive zone in the eastern part of the caldera contain water of only 73/sup 0/C and consist of highly zeolitized tuffs and ashes in the places that were tested. A deeper zone near Whitmore Hot Springs is somewhat more promising in potential for hot water, but owing to the extensive alteration prevalent in the caldera the presence of hot water cannot be definitely assumed. The resistivity results indicate that most of the past hydrothermal activity, and probably most of the present activity, is controlled by fracture systems related to regional Sierran faulting.« less

  8. Goechemical and Hydrogeochemical Properties of Cappadocia Geothermal Province

    NASA Astrophysics Data System (ADS)

    Furkan Sener, Mehmet; Sener, Mehmet; Uysal, Tonguc

    2016-04-01

    In order to determine the geothermal resource potential of Niǧde, Nevşehir and Aksaray provinces in Central Anatolian Volcanic Province (CAVP), geothermal fluids, surface water, and alteration rock samples from the Cappadocia volcanic zone in Turkey were investigated for their geochemical and stable isotopic characteristics in light of published geological and tectonic studies. Accordingly, the Cappadocia Geothermal Province (CGP) has two different geothermal systems located along tectonic zones including five active and two potential geothermal fields, which are located between Tuzgölü Fault Zone and Keçiboyduran-Melendiz Fault and north of Keçiboyduran-Melendiz Fault. Based on water chemistry and isotope compositions, samples from the first area are characterized by Ca-Mg-HCO3 ve Ca-HCO3 type mineral poor waters and Ca-Na-SO4 and Ca-Mg-SO4 type for the cold waters and the hot waters, respectively, whereas hot waters from the second area are Na-Cl-HCO3 and Ca-Na-HCO3 type mineral poor waters. According to δ18O and δ2H isotope studies, the geothermal waters are fed from meteoric waters. Results of silica geothermometer indicate that the reservoir temperature of Dertalan, Melendiz Mount, Keçiboyduran Mount, Hasan Mount (Keçikalesi), Ziga, Acıgöl, and Derinkuyu geothermal waters are 150-173 oC, 88-117 oC, 91-120 oC, 94-122 oC, 131-156 oC, 157-179 oC; 152-174 oC and 102-130 oC, respectively. The REE composition of geothermal fluids, surface water, and mineral precipitates indicate that temperature has a strong effect on REE fractionation of the sampled fluids. Eu- and Ce- anomalies (Eu/Eu*, Ce/Ce*) are visible in several samples, which are related to the inheritance from the host reservoir rocks and redox-controlled fractionation of these elements during water-rock interactions. REE and Yttrium geochemistry results of altered rock samples and water samples, which were taken from same locations exhibited quite similar features in each system. Hence, it was

  9. Geologic Map and GIS Data for the Patua Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    2011-10-31

    Patua—ESRI Geodatabase (ArcGeology v1.3): - Contains all the geologic map data, including faults, contacts, folds, veins, dikes, unit polygons, and attitudes of strata and faults. - List of stratigraphic units. - Locations of geothermal wells. - Locations of 40Ar/39Ar and tephra samples.

  10. Alaska Geothermal Sites Map and Database: Bringing together legacy and new geothermal data for research, exploration and development

    NASA Astrophysics Data System (ADS)

    Clough, J. G.; Harun, N. T.; Hughes, C. A.; Weakland, J. R.; Cameron, C. E.

    2013-12-01

    Geothermal exploration activities in Alaska from the late 1970s into the 1980s generated vast quantities of scientific data that currently is in unpublished, forgotten and obscure, as well as published formats. Alaska has 61 hot springs (hotter than 50°C) and 34 'warm to cool springs' (cooler than 50°C). Thirty-seven thermal springs are located within the Aleutian and Alaska Peninsula volcanic arc into and are related to elevated heat flows in areas of arc volcanism as well as crustal scale faults associated with accretionary tectonism. The central interior belt that extends from the Seward Peninsula to Circle Hot Springs contains 37 thermal springs that formed due to mostly extensional tectonic forces. An additional 17 thermal springs are in southeast Alaska and 4 are in the Wrangell Mountains. A new cycle of geothermal exploration is underway in Alaska and is producing a wealth of new geothermal data. The Alaska Division of Geological and Geophysical Surveys (ADGGS), funded by the National Geothermal Data System, is compiling both new and legacy geothermal data into a comprehensive database accessible on the ADGGS website. ADGGS has created a new ';Geothermal Sites of Alaska Map' and associated database that includes data on geothermal hot springs, direct use of geothermal resources, volcanic vents, aqueous geochemistry, borehole temperatures, core descriptions, rock chemistry, earthquakes in proximity to hot springs, and active faults. Geothermal hot springs includes locality, temperature, flow rate, sources and related resources. Direct use of geothermal resources contains facilities, capacity, energy use, temperature, flow rate and contact information from geothermal hot springs that are or have recently been used for recreational use, space heating, agricultural or energy use. Volcanic vents records 395 volcanic vents and fumaroles throughout the state that are Holocene or younger. It includes their age, location, elevation, geologic history, composition

  11. Geothermal tomorrow 2008

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None, None

    2009-01-18

    Contributors from the Geothermal Technologies Program and the geothermal community highlight the current status and activities of the Program and the development of the global resource of geothermal energy.

  12. Subsurface temperatures and geothermal gradients on the North Slope, Alaska

    USGS Publications Warehouse

    Collett, Timothy S.; Bird, Kenneth J.; Magoon, Leslie B.

    1989-01-01

    Geothermal gradients as interpreted from a series of high-resolution stabilized well-bore-temperature surveys from 46 North Slope, Alaska, wells vary laterally and vertically throughout the near-surface sediment (0-2,000 m). The data from these surveys have been used in conjunction with depths of ice-bearing permafrost, as interpreted from 102 well logs, to project geothermal gradients within and below the ice-bearing permafrost sequence. The geothermal gradients calculated from the projected temperature profiles are similar to the geothermal gradients measured in the temperature surveys. Measured and projected geothermal gradients in the ice-bearing permafrost sequence range from 1.5??C/100m in the Prudhoe Bay area to 5.1??C/100m in the National Petroleum Reserve in Alaska (NPRA).

  13. Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

    USGS Publications Warehouse

    Jones, Perry M.; Trost, Jared J.; Erickson, Melinda L.

    2016-10-19

    OverviewThis study assessed lake-water levels and regional and local groundwater and surface-water exchanges near northeast Twin Cities Metropolitan Area lakes applying three approaches: statistical analysis, field study, and groundwater-flow modeling.  Statistical analyses of lake levels were completed to assess the effect of physical setting and climate on lake-level fluctuations of selected lakes. A field study of groundwater and surface-water interactions in selected lakes was completed to (1) estimate potential percentages of surface-water contributions to well water across the northeast Twin Cities Metropolitan Area, (2) estimate general ages for waters extracted from the wells, and (3) assess groundwater inflow to lakes and lake-water outflow to aquifers downgradient from White Bear Lake.  Groundwater flow was simulated using a steady-state, groundwater-flow model to assess regional groundwater and surface-water exchanges and the effects of groundwater withdrawals, climate, and other factors on water levels of northeast Twin Cities Metropolitan Area lakes.

  14. Update on subsidence at the Wairakei-Tauhara geothermal system, New Zealand

    USGS Publications Warehouse

    Allis, R.; Bromley, C.; Currie, S.

    2009-01-01

    The total subsidence at the Wairakei field as a result of 50 years of geothermal fluid extraction is 15 ?? 0.5 m. Subsidence rates in the center of the subsidence bowl have decreased from over 450 mm/year during the 1970s to 80-90 mm/year during 2000-2007. The location of the bowl, adjacent to the original liquid outflow zone of the field, has not changed significantly. Subsidence at the Tauhara field due to Wairakei production was not as well documented in the early years but appeared later and has been less intense than at Wairakei. Total subsidence of 2.6 ?? 0.5 m has also occurred close to the original liquid outflow zone of this field, and maximum subsidence rates in this area today are in the 80-100 mm/year range. In the western part of the Wairakei field, near the area of hot upflow, subsidence rates have approximately doubled during the last 20 years to 30-50 mm/year. This increase appears to be have been caused by declining pressure in the underlying steam zone in this area, which is tapped by some production wells. At Tauhara field, two areas of subsidence have developed since the 1990s with rates of 50-65 mm/year. Although less well-determined, this subsidence may also be caused by declining pressure in shallow steam zones. The cause of the main subsidence bowls in the Wairakei-Tauhara geothermal system is locally high-compressibility rocks within the Huka Falls Formation (HFF), which are predominantly lake sediments and an intervening layer of pumice breccia. At Wairakei, casing deformation suggests the greatest compaction is at 150-200 m depth. The cause of the large compressibility is inferred to be higher clay content in the HFF due to intense hydrothermal alteration close to the natural fluid discharge areas. Future subsidence is predicted to add an additional 2-4 m to the Wairakei bowl, and 1-2 m elsewhere, but these estimates depend on the assumed production-injection scenarios.

  15. Fluid-rock geochemical interaction for modelling calibration in geothermal exploration in Indonesia

    NASA Astrophysics Data System (ADS)

    Deon, Fiorenza; Barnhoorn, Auke; Lievens, Caroline; Ryannugroho, Riskiray; Imaro, Tulus; Bruhn, David; van der Meer, Freek; Hutami, Rizki; Sibarani, Besteba; Sule, Rachmat; Saptadij, Nenny; Hecker, Christoph; Appelt, Oona; Wilke, Franziska

    2017-04-01

    Indonesia with its large, but partially unexplored geothermal potential is one of the most interesting and suitable places in the world to conduct geothermal exploration research. This study focuses on geothermal exploration based on fluid-rock geochemistry/geomechanics and aims to compile an overview on geochemical data-rock properties from important geothermal fields in Indonesia. The research carried out in the field and in the laboratory is performed in the framework of the GEOCAP cooperation (Geothermal Capacity Building program Indonesia- the Netherlands). The application of petrology and geochemistry accounts to a better understanding of areas where operating power plants exist but also helps in the initial exploration stage of green areas. Because of their relevance and geological setting geothermal fields in Java, Sulawesi and the sedimentary basin of central Sumatra have been chosen as focus areas of this study. Operators, universities and governmental agencies will benefit from this approach as it will be applied also to new green-field terrains. By comparing the characteristic of the fluids, the alteration petrology and the rock geochemistry we also aim to contribute to compile an overview of the geochemistry of the important geothermal fields in Indonesia. At the same time the rock petrology and fluid geochemistry will be used as input data to model the reservoir fluid composition along with T-P parameters with the geochemical workbench PHREEQC. The field and laboratory data are mandatory for both the implementation and validation of the model results.

  16. Colorado geothermal commercialization program: community development of geothermal energy in Pagosa Springs, Colorado

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Coe, B.A.

    1980-01-01

    A district heating system for the Pagosa Springs central business district is in the planning stage. A detailed analysis of the project is presented. It comprises area and site specific studies and describes in detail the recent, current, anticipated, and postulated geothermal development activities. (MHR)

  17. Geothermal probabilistic cost study

    NASA Technical Reports Server (NTRS)

    Orren, L. H.; Ziman, G. M.; Jones, S. C.; Lee, T. K.; Noll, R.; Wilde, L.; Sadanand, V.

    1981-01-01

    A tool is presented to quantify the risks of geothermal projects, the Geothermal Probabilistic Cost Model (GPCM). The GPCM model was used to evaluate a geothermal reservoir for a binary-cycle electric plant at Heber, California. Three institutional aspects of the geothermal risk which can shift the risk among different agents was analyzed. The leasing of geothermal land, contracting between the producer and the user of the geothermal heat, and insurance against faulty performance were examined.

  18. Hydrology, nutrient concentrations, and nutrient yields in nearshore areas of four lakes in northern Wisconsin, 1999-2001

    USGS Publications Warehouse

    Graczyk, David J.; Hunt, Randall J.; Greb, Steven R.; Buchwald, Cheryl A.; Krohelski, James T.

    2003-01-01

    The effects of shoreline development on water quality and nutrient yields in nearshore areas of four lakes in northern Wisconsin were investigated from October 1999 through September 2001. The study measured surface runoff and ground-water flows from paired developed (sites containing lawn, rooftops, sidewalks, and driveways) and undeveloped (mature and immature woods) catchments adjacent to four lakes in northern Wisconsin. Water samples from surface runoff and ground water were collected and analyzed for nutrients. Coupled with water volumes, loads and subsequent yields of selected constituents were computed for developed and undeveloped catchments. The median runoff from lawn surfaces ranged from 0.0019 to 0.059 inch over the catchment area. Median surface runoff estimates from the wooded catchments were an order of magnitude less than those from the lawn catchments. The increased water volumes from the lawn catchments resulted in greater nutrient loads and subsequent annual nutrient yields from the developed sites. Soil temperature and soil moisture were measured at two sites with mixed lawn and wooded areas. At both of these sites, the area covered with a lawn commonly was warmer than the wooded area. No consistent differences in soil moisture were found. A ground-water model was constructed to simulate the local flow systems at two of the paired catchments. Model simulations showed that much of the ground water delivered to the lake originated from distant areas that did not contribute runoff directly to the lake. Surface runoff and ground-water nutrient concentrations from the lawn and wooded catchments did not have apparent patterns. Some of the median concentrations from lawns were significantly different (at the 0.05 significance level) from those at wooded catchments. Water wells and piezometers were sampled for chemical analyses three times during the study period. Variability in the shallow ground-water chemistry over time in the lawn samples was

  19. Hawaii geothermal project

    NASA Technical Reports Server (NTRS)

    Kamins, R. M.

    1974-01-01

    Hawaii's Geothermal Project is investigating the occurrence of geothermal resources in the archipelago, initially on the Island of Hawaii. The state's interest in geothermal development is keen, since it is almost totally dependent on imported oil for energy. Geothermal development in Hawaii may require greater participation by the public sector than has been true in California. The initial exploration has been financed by the national, state, and county governments. Maximization of net benefits may call for multiple use of geothermal resources; the extraction of by-products and the application of treated effluents to agricultural and aquacultural uses.

  20. Distribution of native mussel (unionidae) assemblages in coastal areas of Lake Erie, Lake St. Clair, and connecting channels, twenty-five years after a dreissenid invasion

    USGS Publications Warehouse

    Zanatta, David T.; Bossenbroek, Jonathan M.; Burlakova, Lyubov E.; Crail, Todd D.; Szalay, Ferenc de; Griffith, Traci A.; Kapusinski, Douglas; Karatayev, Alexander Y.; Krebs, Robert A.; Meyer, Elizabeth S.; Paterson, Wendy L.; Prescott, Trevor J.; Rowe, Matthew T.; Schloesser, Donald W.; Walsh, Mary C.

    2015-01-01

    Over the past 25 years, unionid mussels in the Laurentian Great Lakes of North America have been adversely impacted by invasive dreissenid mussels, which directly (e.g., by attachment to unionid shells) and indirectly (e.g., by competing for food) cause mortality. Despite the invasion, unionids have survived in several areas in the presence of dreissenid mussels. We investigated current spatial patterns in these native mussel refuges based on surveys for unionid mussels across 48 sampling locations (141 sites) in 2011 and 2012, and documented species abundance and diversity in coastal areas of lakes St. Clair and Erie. The highest-quality assemblages of native mussels (densities, richness, and diversity) appear to be concentrated in the St. Clair delta, where abundance continues to decline, as well as in in Thompson Bay of Presque Isle in Lake Erie and in just a few coastal wetlands and drowned river-mouths in the western basin of Lake Erie. The discovery of several new refuge areas suggests that unionids have a broader distribution within the region than previously thought.

  1. Resistivity imaging of Aluto-Langano geothermal field using 3-D magnetotelluric inversion

    NASA Astrophysics Data System (ADS)

    Cherkose, Biruk Abera; Mizunaga, Hideki

    2018-03-01

    Magnetotelluric (MT) method is a widely used geophysical method in geothermal exploration. It is used to image subsurface resistivity structures from shallow depths up to several kilometers of depth. Resistivity imaging using MT method in high-enthalpy geothermal systems is an effective tool to identify conductive clay layers that cover the geothermal systems and to detect a potential reservoir. A resistivity model is vital for deciding the location of pilot and production sites at the early stages of a geothermal project. In this study, a 3-D resistivity model of Aluto-Langano geothermal field was constructed to map structures related to a geothermal resource. The inversion program, ModEM was used to recover the 3-D resistivity model of the study area. The 3-D inversion result revealed the three main resistivity structures: a high-resistivity surface layer related to unaltered volcanic rocks at shallow depth, underlain by a conductive zone associated with the presence of conductive clay minerals, predominantly smectite. Beneath the conductive layer, the resistivity increases gradually to higher values related to the formation of high-temperature alteration minerals such as chlorite and epidote. The resistivity model recovered from 3-D inversion in Aluto-Langano corresponds very well to the conceptual model for high-enthalpy volcanic geothermal systems. The conductive clay cap is overlying the resistive propylitic upflow zone as confirmed by the geothermal wells in the area.

  2. Calculation of area and volume for the north part of Great Salt Lake, Utah

    USGS Publications Warehouse

    Baskin, Robert L.

    2006-01-01

    The U.S. Geological Survey, in cooperation with the Utah Department of Natural Resources, Division of Forestry, Fire, and State Lands, collected bathymetric data for the north part of Great Salt Lake during the spring and early summer of 2006 using a single-beam, high-definition fathometer and real-time differential global positioning system. About 5.2 million depth measurements were collected along more than 765 miles (1,230 kilometers) of survey transects. Sound-velocity profiles were obtained in conjunction with the bathymetric data to provide time-of-travel corrections to the depth calculations. Data were processed with commercial hydrographic software and exported into geographic information system (GIS) software for mapping and calculation of area and volume. Area and volume calculations show a maximum area of about 385,000 acres (1,560 square kilometers) and a maximum volume of about 5,693,000 acre-feet (about 7 cubic kilometers) at a water-surface altitude of 4,200 feet (1,280 meters). Minimum natural water-surface altitude of the north part of Great Salt Lake is just below 4,167 feet (1,270 meters) in the area just north of the Union Pacific railroad causeway halfway between Saline and the western edge of the lake. The north part of Great Salt Lake generally grades gradually to the west and north and is bounded by steep scarps along its eastern border. Calculations for area and volume are based on a low altitude of 4,167 feet (1,270 meters) to a high altitude of 4,200 feet (1,280 meters).

  3. Tracing Injection Fluids in Engineered Geothermal Systems

    NASA Astrophysics Data System (ADS)

    Rose, P. E.; Leecaster, K.; Mella, M.; Ayling, B.; Bartl, M. H.

    2011-12-01

    The reinjection of produced fluids is crucial to the effective management of geothermal reservoirs, since it provides a mechanism for maintaining reservoir pressures while allowing for the disposal of a toxic byproduct. Tracers are essential to the proper location of injection wells since they are the only known tool for reliably characterizing the flow patterns of recirculated fluids. If injection wells are placed too close to production wells, then reinjected fluids do not have sufficient residence time to extract heat from the reservoir and premature thermal breakthrough results. If injection wells are placed too far away, then the reservoir risks unacceptable pressure loss. Several thermally stable compounds from a family of very detectable fluorescent organic compounds (the naphthalene sulfonates) were characterized and found to be effective for use as geothermal tracers. Through batch-autoclave reactions, their Arrhenius pseudo-first-order decay-rate constants were determined. An analytical method was developed that allows for the laboratory determination of concentrations in the low parts-per-trillion range. Field experiments in numerous geothermal reservoirs throughout the world have confirmed the laboratory findings. Whereas conservative tracers such as the naphthalene sulfonates are effective tools for indicating interwell flow patterns and for measuring reservoir pore volumes, 'reactive' tracers can be used to constrain fracture surface area, which is the effective area for heat extraction. This is especially important for engineered geothermal system (EGS) wells, since reactive tracers can be used to measure fracture surface area immediately after drilling and while the well stimulation equipment is still on site. The reactive properties of these tracers that can be exploited to constrain fracture surface area are reversible sorption, contrasting diffusivity, and thermal decay. Laboratory batch- and flow-reactor experiments in combination with numerical

  4. Basics of applied geothermal engineering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wehlage, E.F.

    1976-01-01

    The following chapters are included: (1) born of fire, (2) milestones with tectonics, (3) a world in geothermal review, (4) simple mechanical and electrical facts for geothermal, (5) elementary hydraulics and pumping, (6) elementary heat, (7) application of steam, (8) geothermal hydroponics, (9) designing for a geothermal diary, (10) review of geothermal prime movers for power production, (11) design procedures-geothermal house heating, (12) cooling with geothermal refrigeration, and (13) geothermal synthesis-new heat for the world. (MOW)

  5. Pronounced chemical response of Subarctic lakes to climate-driven losses in surface area

    USGS Publications Warehouse

    Lewis, Tyler L.; Lindberg, Mark S.; Schmutz, Joel A.; Heglund, Patricia J.; Rover, Jennifer R.; Koch, Joshua C.; Bertram, Mark R.

    2015-01-01

    Losses in lake area have been observed for several Arctic and Subarctic regions in recent decades, with unknown consequences for lake ecosystems. These reductions are primarily attributed to two climate-sensitive mechanisms, both of which may also cause changes in water chemistry: (i) increased imbalance of evaporation relative to inflow, whereby increased evaporation and decreased inflow act to concentrate solutes into smaller volumes; and (ii) accelerated permafrost degradation, which enhances sublacustrine drainage while simultaneously leaching previously frozen solutes into lakes. We documented changes in nutrients [total nitrogen (TN), total phosphorus (TP)] and ions (calcium, chloride, magnesium, sodium) over a 25 year interval in shrinking, stable, and expanding Subarctic lakes of the Yukon Flats, Alaska. Concentrations of all six solutes increased in shrinking lakes from 1985–1989 to 2010–2012, while simultaneously undergoing little change in stable or expanding lakes. This created a present-day pattern, much weaker or absent in the 1980s, in which shrinking lakes had higher solute concentrations than their stable or expanding counterparts. An imbalanced evaporation-to-inflow ratio (E/I) was the most likely mechanism behind such changes; all four ions, which behave semiconservatively and are prone to evapoconcentration, increased in shrinking lakes and, along with TN and TP, were positively related to isotopically derived E/I estimates. Moreover, the most conservative ion, chloride, increased >500% in shrinking lakes. Conversely, only TP concentration was related to probability of permafrost presence, being highest at intermediate probabilities. Overall, the substantial increases of nutrients (TN >200%, TP >100%) and ions (>100%) may shift shrinking lakes towards overly eutrophic or saline states, with potentially severe consequences for ecosystems of northern lakes.

  6. Technical Feasibility Aspects of the Geothermal Resource Reporting Methodology (GRRM)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Badgett, Alex; Young, Katherine R; Dobson, Patrick F.

    This paper reviews the technical assessment of the Geothermal Research Reporting Methodology (GRRM, http://en.openei.org/wiki/GRRM) being developed for reporting geothermal resources and project progress. The goal of the methodology is to provide the U.S. Department of Energy's Geothermal Technologies Office (GTO) with a consistent and comprehensible means of evaluating the impacts of its funding programs. The GRRM is designed to provide uniform assessment criteria for geothermal resource grades and developmental phases of geothermal resource exploration and development. This resource grade system provides information on twelve attributes of geothermal resource locations (e.g., temperature, permeability, land access) to indicate potential for geothermal development.more » The GTO plans to use these Protocols to help quantitatively identify the greatest barriers to geothermal development, develop measureable program goals that will have the greatest impact to geothermal deployment, objectively evaluate proposals based (in part) on a project's ability to contribute to program goals, monitor project progress, and report on GTO portfolio performance. The GRRM assesses three areas of geothermal potential: geological, socio-economic, and technical. Previous work and publications have discussed the work done on the geological aspects of this methodology (Young et al. 2015c); this paper details the development of the technical assessment of the GRRM. Technical development attributes considered include: reservoir management, drilling, logistics, and power conversion.« less

  7. VITELLOGENIN GENE EXPRESSION IN FATHEAD MINNOWS AND PEARL DACE FROM CONTROL (NON-DOSED) AND LAKES DOSED WITH EE2 IN THE CANADIAN EXPERIMENTAL LAKES AREA

    EPA Science Inventory

    A whole-lake endocrine disruption experiment was conducted by Fisheries and Oceans Canada at the Experimental Lakes Area (ELA) in northwestern Ontario for three years beginning in 2001. This experiment examined population, organismal, biochemical and cellular-level effects in la...

  8. Comparison of three methods for long-term monitoring of boreal lake area using Landsat TM and ETM+ imagery

    USGS Publications Warehouse

    Roach, Jennifer K.; Griffith, Brad; Verbyla, David

    2012-01-01

    Programs to monitor lake area change are becoming increasingly important in high latitude regions, and their development often requires evaluating tradeoffs among different approaches in terms of accuracy of measurement, consistency across multiple users over long time periods, and efficiency. We compared three supervised methods for lake classification from Landsat imagery (density slicing, classification trees, and feature extraction). The accuracy of lake area and number estimates was evaluated relative to high-resolution aerial photography acquired within two days of satellite overpasses. The shortwave infrared band 5 was better at separating surface water from nonwater when used alone than when combined with other spectral bands. The simplest of the three methods, density slicing, performed best overall. The classification tree method resulted in the most omission errors (approx. 2x), feature extraction resulted in the most commission errors (approx. 4x), and density slicing had the least directional bias (approx. half of the lakes with overestimated area and half of the lakes with underestimated area). Feature extraction was the least consistent across training sets (i.e., large standard error among different training sets). Density slicing was the best of the three at classifying small lakes as evidenced by its lower optimal minimum lake size criterion of 5850 m2 compared with the other methods (8550 m2). Contrary to conventional wisdom, the use of additional spectral bands and a more sophisticated method not only required additional processing effort but also had a cost in terms of the accuracy and consistency of lake classifications.

  9. Play-fairway analysis for geothermal exploration: Examples from the Great Basin, western USA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Siler, Drew L; Faulds, James E

    2013-10-27

    Elevated permeability within fault systems provides pathways for circulation of geothermal fluids. Future geothermal development depends on precise and accurate location of such fluid flow pathways in order to both accurately assess geothermal resource potential and increase drilling success rates. The collocation of geologic characteristics that promote permeability in a given geothermal system define the geothermal ‘fairway’, the location(s) where upflow zones are probable and where exploration efforts including drilling should be focused. We define the geothermal fairway as the collocation of 1) fault zones that are ideally oriented for slip or dilation under ambient stress conditions, 2) areas withmore » a high spatial density of fault intersections, and 3) lithologies capable of supporting dense interconnected fracture networks. Areas in which these characteristics are concomitant with both elevated temperature and fluids are probable upflow zones where economic-scale, sustainable temperatures and flow rates are most likely to occur. Employing a variety of surface and subsurface data sets, we test this ‘play-fairway’ exploration methodology on two Great Basin geothermal systems, the actively producing Brady’s geothermal system and a ‘greenfield’ geothermal prospect at Astor Pass, NV. These analyses, based on 3D structural and stratigraphic framework models, reveal subsurface characteristics about each system, well beyond the scope of standard exploration methods. At Brady’s, the geothermal fairways we define correlate well with successful production wells and pinpoint several drilling targets for maintaining or expanding production in the field. In addition, hot-dry wells within the Brady’s geothermal field lie outside our defined geothermal fairways. At Astor Pass, our play-fairway analysis provides for a data-based conceptual model of fluid flow within the geothermal system and indicates several targets for exploration drilling.« less

  10. Guidebook to Geothermal Finance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Salmon, J. P.; Meurice, J.; Wobus, N.

    This guidebook is intended to facilitate further investment in conventional geothermal projects in the United States. It includes a brief primer on geothermal technology and the most relevant policies related to geothermal project development. The trends in geothermal project finance are the focus of this tool, relying heavily on interviews with leaders in the field of geothermal project finance. Using the information provided, developers and investors may innovate in new ways, developing partnerships that match investors' risk tolerance with the capital requirements of geothermal projects in this dynamic and evolving marketplace.

  11. Shallow Geothermal Admissibility Maps: a Methodology to Achieve a Sustainable Development of Shallow Geothermal Energy with Regards to Groundwater Resources

    NASA Astrophysics Data System (ADS)

    Bréthaut, D.; Parriaux, A.; Tacher, L.

    2009-04-01

    Implantation and use of shallow geothermal systems may have environmental impacts. Traditionally, risks are divided into 2 categories: direct and indirect. Direct risks are linked with the leakage of the circulating fluid (usually water with anti-freeze) of ground source heat pumps into the underground which may be a source of contamination. Indirect risks are linked with the borehole itself and the operation of the systems which can modify the groundwater flow, change groundwater temperature and chemistry, create bypasses from the surfaces to the aquifers or between two aquifers. Groundwater source heat pumps (GWSHP) may provoke indirect risks, while ground source heat pumps (GSHP) may provoke both direct and indirect risks. To minimize those environmental risks, the implantation of shallow geothermal systems must be regulated. In 2007, more than 7000 GSHP have been installed in Switzerland, which represents 1.5 Mio drilled meters. In the canton of Vaud, each shallow geothermal project has to be approved by the Department of the Environment. Approximately 1500 demands have been treated during 2007, about 15 times more than in 1990. Mapping shallow geothermal systems implantation restrictions due to environmental constrains permits: 1) to optimize the management and planning of the systems, 2) to minimize their impact on groundwater resources and 3) to facilitate administrative procedures for treating implantation demands. Such maps are called admissibility maps. Here, a methodology to elaborate them is presented and tested. Interactions between shallow geothermal energy and groundwater resources have been investigated. Admissibility criteria are proposed and structured into a flow chart which provides a decision making tool for shallow geothermal systems implantation. This approach has been applied to three areas of West Switzerland ranging from 2 to 6 km2. For each area, a geological investigation has been realized and complementary territorial information (e

  12. Aquatic balance in Vegoritis Lake, West Macedonia, Greece, relating to lignite mining works in the area

    NASA Astrophysics Data System (ADS)

    Dimitrakopoulos, D.; Grigorakou, E.; Koumantakis, J.

    2003-04-01

    Vegoritis Lake, which is located at Vegoritis closed Basin in West Macedonia, Greece, is the biggest lake in Greece. In 1994 the area of the lake was 35 Km2 with maximum depth 42 m at the northwestern part of the lake. It is the final receiving body of the surface runoff of the hydrological basin. Moreover, it is the surficial appearance of an enormous and not well-known karstic aquifer. Being a closed hydrological basin any interference in surface or groundwater conditions in every part of its area affects the level of the lake. The level of the lake in 1900 was 525 masl, in 1942 was 542 masl reaching the higher level of 543 masl in 1956. The increase of the level of the lake was due to the drainage of Ptolemais (Sarigiol) swamp through Soulou drain ditches that transfer the water in the lake. Since then, a continuous drawdown took place with small periods of rising of water level. Today, the level of the lake is declined in a smaller rate having reached the level of 510 masl. Water coming from the lake has been used in the past, and in some cases still does, for agricultural, industrial and domestic use, for hydropower generation and for the cooling system of power plants. Moreover, P.P.C. (Public Power Corporation of Greece) develops an intense activity in the area with the exploitation of the lignite deposits of the basin and power generation in several Power Plants. Few years ago significant quantities from Vegoritis Lake were used for hydro power of Agras Power Plant. With the elaboration of the existent data (water level measurements, recharge, discharge) the connection between the lowering of the surface of the lake and the subtracted quantities through the Arnissa Tunel the first years of its use, is obvious. The last twenty years the condition has change. Outflow through the Arnissa Tunnel for hydropower has stopped. The continued lowering of the level of the lake is caused, mainly, by overexploitation due to the intense increase of the irrigating land

  13. Midcontinent microcosm: Geology of the Atkins lake - Marengo falls area (Field trip 2)

    USGS Publications Warehouse

    Bjørnerud, Marcia; Cannon, William F.

    2011-01-01

    Archean and Proterozoic rocks exposed over about 16km2 between Atkins Lake and Coffee Lake in southeastern Bayfield County (Fig. 1) chronicle almost all of the major Precambrian geologic events in the history of the southern Superior Craton. The oldest rocks are part of a locally gneissic quartz monzonite complex, the Puritan Batholith, with an igneous Rb-Sr age of 2710+140 Ma (Sims et al., 1977). At the regional scale, this complex is part of one of the youngest Archean granite-greenstone belts in the Superior Province, and it intrudes greenstones of the Neoarchean Ramsay Formation. In the Atkins Lake – Marengo River area, the Puritan Batholith is nonconformably overlain by the Paleoproterozoic (ca. 2200 Ma) Bad River Dolomite. The Bad River Dolomite is in turn separated by an unconformity from rocks of the ca. 1875 Ma Menominee Group (Palms Formation and Ironwood Iron-formation), which locally contain mafic volcanic rocks and diabase sills (Cannon et al., 2008). These Paleoproterozoic rocks provide insight into climate and biogeochemical cycles during the transition to an oxidizing atmosphere (Bekker et al., 2006) and have deformational fabrics (folds, strong cleavage, local mylonite zones) that record the ca. 1850 Ma Penokean Orogeny. The youngest rocks in the area are Mesoproterozoic basaltic lava flows (Siemens Creek Volcanics, ca. 1110 Ma) and a layered mafic complex (the Mineral Lake Intrusion, also ca. 1100 Ma), both related to the Mid-continent Rift. All of the stratified units show static contact metamorphic textures near their contacts with the Mineral Lake Intrusion. Thus the area constitutes a microcosm of the regional bedrock geology, and the cross-cutting relationships among the units provide clear constraints on the relative timing of different phases of deformation and magmatism (Cannon etal., 2008, Bjørnerud, 2010a).

  14. Bathymetric contour map, surface area and capacity table, and bathymetric difference map for Clearwater Lake near Piedmont, Missouri, 2017

    USGS Publications Warehouse

    Richards, Joseph M.; Huizinga, Richard J.

    2018-06-19

    Clearwater Lake, on the Black River near Piedmont in Reynolds County, Missouri, was constructed in 1948 and is operated by the U.S. Army Corps of Engineers for flood-risk reduction, recreation, and fish and wildlife habitat. The lake area is about 1,800 acres with about 34 miles of shoreline at the conservation pool elevation of 498 feet. Since the completion of the lake in 1948, sedimentation likely has caused the storage capacity of the lake to decrease gradually. The loss of storage capacity can decrease the effectiveness of the lake to mitigate flooding, and excessive sediment accumulation also can reduce aquatic habitat in some areas of the lake. Many lakes operated by the U.S. Army Corps of Engineers have periodic bathymetric and sediment surveys to monitor the status of the lake. The U.S. Geological Survey completed one such survey of Clearwater Lake in 2008 during a period of high lake level using bathymetric surveying equipment consisting of a multibeam echosounder, a singlebeam echosounder, 1/3 arc-second National Elevation Dataset data (used outside the multibeam echosounder survey extent), and the waterline derived from 2008 aerial light detection and ranging (lidar) data. In May 2017, the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, surveyed the bathymetry of Clearwater Lake to prepare an updated bathymetric map and a surface area and capacity table. The 2008 survey was contrasted with the 2017 survey to document the changes in the bathymetric surface of the lake.

  15. Evidence of Lake Trout reproduction at Lake Michigan's mid-lake reef complex

    USGS Publications Warehouse

    Janssen, J.; Jude, D.J.; Edsall, T.A.; Paddock, R.W.; Wattrus, N.; Toneys, M.; McKee, P.

    2006-01-01

    The Mid-Lake Reef Complex (MLRC), a large area of deep (> 40 m) reefs, was a major site where indigenous lake trout (Salvelinus namaycush) in Lake Michigan aggregated during spawning. As part of an effort to restore Lake Michigan's lake trout, which were extirpated in the 1950s, yearling lake trout have been released over the MLRC since the mid-1980s and fall gill net censuses began to show large numbers of lake trout in spawning condition beginning about 1999. We report the first evidence of viable egg deposition and successful lake trout fry production at these deep reefs. Because the area's existing bathymetry and habitat were too poorly known for a priori selection of sampling sites, we used hydroacoustics to locate concentrations of large fish in the fall; fish were congregating around slopes and ridges. Subsequent observations via unmanned submersible confirmed the large fish to be lake trout. Our technological objectives were driven by biological objectives of locating where lake trout spawn, where lake trout fry were produced, and what fishes ate lake trout eggs and fry. The unmanned submersibles were equipped with a suction sampler and electroshocker to sample eggs deposited on the reef, draw out and occasionally catch emergent fry, and collect egg predators (slimy sculpin Cottus cognatus). We observed slimy sculpin to eat unusually high numbers of lake trout eggs. Our qualitative approaches are a first step toward quantitative assessments of the importance of lake trout spawning on the MLRC.

  16. Geothermal energy

    NASA Astrophysics Data System (ADS)

    Manzella, A.

    2015-08-01

    Geothermal technologies use renewable energy resources to generate electricity and direct use of heat while producing very low levels of greenhouse-gas (GHG) emissions. Geothermal energy is stored in rocks and in fluids circulating in the underground. Electricity generation usually requires geothermal resources temperatures of over 100°C. For heating, geothermal resources spanning a wider range of temperatures can be used in applications such as space and district heating (and cooling, with proper technology), spa and swimming pool heating, greenhouse and soil heating, aquaculture pond heating, industrial process heating and snow melting. Geothermal technology, which has focused so far on extracting naturally heated steam or hot water from natural hydrothermal reservoirs, is developing to more advanced techniques to exploit the heat also where underground fluids are scarce and to use the Earth as a potential energy battery, by storing heat. The success of the research will enable energy recovery and utilization from a much larger fraction of the accessible thermal energy in the Earth's crust.

  17. Recent exploration and development of geothermal energy resources in the Escalante desert region, Southwestern Utah

    USGS Publications Warehouse

    Blackett, Robert E.; Ross, Howard P.

    1994-01-01

    Development of geothermal resources in southwest Utah's Sevier thermal area continued in the early 1990s with expansion of existing power-generation facilities. Completion of the Bud L. Bonnett geothermal power plant at the Cove Fort-Sulphurdale geothermal area brought total power generation capacity of the facility to 13.5 MWe (gross). At Cove Fort-Sulphurdate, recent declines in steam pressures within the shallow, vapor-dominated part of the resource prompted field developers to complete additional geothermal supply wells into the deeper, liquid-dominated portion of the resource. At Roosevelt Hot Springs near Milford, Intermountain Geothermal Company completed an additional supply well for Utah Power and Light Company's single-flash, Blundell plant. with the increased geothermal fluid supply from the new well, the Blundell plant now produces about 26 MWe (gross). The authors conducted several geothermal resource studies in undeveloped thermal areas in southwest Utah. Previous studies at Newcastle revealed a well-defined, self-potential minimum coincident with the intersection of major faults and the center of the heatflow anomaly. A detailed self-potential survey at Wood's Ranch, an area in northwest Iron County where thermal water was encountered in shallow wells, revealed a large (5,900 ?? 2,950 feet [1,800 ?? 900 m]) northeast-oriented self-potential anomaly which possibly results from the flow of shallow thermal fluid. Chemical geothermometry applied to Wood's Ranch water samples suggest reservoir temperatures between 230 and 248??F (110 and 120??C). At the Thermo Hot Springs geothermal area near Minersville, detailed self-potential surveys have also revealed an interesting 100 mV negative anomaly possibly related to the upward flow of hydrothermal fluid.

  18. 76 FR 21329 - Humboldt-Toiyabe National Forest; Nevada; Environmental Impact Statement for Geothermal Leasing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-15

    ... Impact Statement for Geothermal Leasing on the Humboldt-Toiyabe National Forest AGENCY: Forest Service... National Forest System (NFS) lands for geothermal leasing availability. The project area includes NFS lands... available for geothermal leasing, and if so, to identify reasonable and necessary conditions to protect...

  19. Institutional and environmental problems in geothermal resource development

    NASA Technical Reports Server (NTRS)

    Maslan, F.; Gordon, T. J.; Deitch, L.

    1974-01-01

    A number of regulatory and institutional impediments to the development of geothermal energy exist. None of these seem likely to prevent the development of this energy source, but in the aggregate they will pace its growth as certainly as the technological issues. The issues are associated with the encouragement of exploration and development, assuring a market for geothermal steam or hot water, and accomplishing the required research and development in a timely manner. The development of geothermal energy in the United States at a high level is apt to cause both favorable and unfavorable, though manageable, impacts in eight major areas, which are discussed.

  20. Spatial heterogeneity in statistical power to detect changes in lake area in Alaskan National Wildlife Refuges

    USGS Publications Warehouse

    Nicol, Samuel; Roach, Jennifer K.; Griffith, Brad

    2013-01-01

    Over the past 50 years, the number and size of high-latitude lakes have decreased throughout many regions; however, individual lake trends have been variable in direction and magnitude. This spatial heterogeneity in lake change makes statistical detection of temporal trends challenging, particularly in small analysis areas where weak trends are difficult to separate from inter- and intra-annual variability. Factors affecting trend detection include inherent variability, trend magnitude, and sample size. In this paper, we investigated how the statistical power to detect average linear trends in lake size of 0.5, 1.0 and 2.0 %/year was affected by the size of the analysis area and the number of years of monitoring in National Wildlife Refuges in Alaska. We estimated power for large (930–4,560 sq km) study areas within refuges and for 2.6, 12.9, and 25.9 sq km cells nested within study areas over temporal extents of 4–50 years. We found that: (1) trends in study areas could be detected within 5–15 years, (2) trends smaller than 2.0 %/year would take >50 years to detect in cells within study areas, and (3) there was substantial spatial variation in the time required to detect change among cells. Power was particularly low in the smallest cells which typically had the fewest lakes. Because small but ecologically meaningful trends may take decades to detect, early establishment of long-term monitoring will enhance power to detect change. Our results have broad applicability and our method is useful for any study involving change detection among variable spatial and temporal extents.

  1. Microearthquakes in the ahuachapan geothermal field, el salvador, central america.

    PubMed

    Ward, P L; Jacob, K H

    1971-07-23

    Microearthquakes occur on a steeply dipping plane interpreted here as the fault that allows hot water to circulate to the surface in the geothermal region. These small earthquakes are common in many geothermal areas and may occur because of the physical or chemical effects of fluids and fluid pressure.

  2. Transported Low-Temperature Geothermal Energy for Thermal End Uses Final Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Zhiyao; Liu, Xiaobing; Gluesenkamp, Kyle R

    2016-10-01

    The use of geothermal energy is an emerging area for improving the nation’s energy resiliency. Conventionally, geothermal energy applications have focused on power generation using high temperature hydrothermal resources or enhanced geothermal systems. However, many low temperature (below 150°C/300°F) geothermal resources are also available but have not been fully utilized. For example, it is estimated that 25 billion barrels of geothermal fluid (mostly water and some dissolved solids) at 176°F to 302°F (80°C to 150°C) is coproduced annually at oil and gas wells in the United States (DOE 2015). The heat contained in coproduced geothermal fluid (also referred as “coproducedmore » water”) is typically wasted because the fluid is reinjected back into the ground without extracting the heat.« less

  3. Lake evolution of the terminal area of Shiyang River drainage in arid China since the last glaciation

    USGS Publications Warehouse

    Shi, Q.; Chen, F.-H.; Zhu, Y.; Madsen, D.

    2002-01-01

    Investigations of geomorphology and sedimentology, and analyses of radiocarbon dates, grain size and carbonate of the sediment at the present-dry closed basin in the terminal area of Shiyang River in arid China were conducted to recover the history of palaeolake change since the last glacial. The terminal area was covered by eolian sand before 13,000 14C BP. Lacustrine deposits covered the eolian sand after 13,000 14C BP, but were succeeded rapidly by eolian or fluvial deposits ca. 11,200-10,000 BP. This fact plus the grain-size distribution and CaCO3 content showed that climate was extremely dry during the last glacial, but wet-dry oscillations characterized the late glacial. A single coalescent lake, over 45 m deep and 2130 km2, formed between 10,000-6400 14C BP in the basin. The lake disintegrated into several shallow carbonate lakes or swamps gradually after 6400 14C BP. Eolian sand reached into the most part of the basin during the period. The lake evolution in the area generally reflects the East Asian summer monsoon history forced by Northern hemisphere insolation. Short time-scale lake fluctuations also existed in the area since the last glacial. ?? 2002 Elsevier Science Ltd and INQUA. All rights reserved.

  4. Glacial lake inventory and lake outburst potential in Uzbekistan.

    PubMed

    Petrov, Maxim A; Sabitov, Timur Y; Tomashevskaya, Irina G; Glazirin, Gleb E; Chernomorets, Sergey S; Savernyuk, Elena A; Tutubalina, Olga V; Petrakov, Dmitriy A; Sokolov, Leonid S; Dokukin, Mikhail D; Mountrakis, Giorgos; Ruiz-Villanueva, Virginia; Stoffel, Markus

    2017-08-15

    Climate change has been shown to increase the number of mountain lakes across various mountain ranges in the World. In Central Asia, and in particular on the territory of Uzbekistan, a detailed assessment of glacier lakes and their evolution over time is, however lacking. For this reason we created the first detailed inventory of mountain lakes of Uzbekistan based on recent (2002-2014) satellite observations using WorldView-2, SPOT5, and IKONOS imagery with a spatial resolution from 2 to 10m. This record was complemented with data from field studies of the last 50years. The previous data were mostly in the form of inventories of lakes, available in Soviet archives, and primarily included localized in-situ data. The inventory of mountain lakes presented here, by contrast, includes an overview of all lakes of the territory of Uzbekistan. Lakes were considered if they were located at altitudes above 1500m and if lakes had an area exceeding 100m 2 . As in other mountain regions of the World, the ongoing increase of air temperatures has led to an increase in lake number and area. Moreover, the frequency and overall number of lake outburst events have been on the rise as well. Therefore, we also present the first outburst assessment with an updated version of well-known approaches considering local climate features and event histories. As a result, out of the 242 lakes identified on the territory of Uzbekistan, 15% are considered prone to outburst, 10% of these lakes have been assigned low outburst potential and the remainder of the lakes have an average level of outburst potential. We conclude that the distribution of lakes by elevation shows a significant influence on lake area and hazard potential. No significant differences, by contrast, exist between the distribution of lake area, outburst potential, and lake location with respect to glaciers by regions. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Geothermal energy

    NASA Astrophysics Data System (ADS)

    Manzella, A.

    2017-07-01

    Geothermal technologies use renewable energy resources to generate electricity and direct use of heat while producing very low levels of greenhouse-gas (GHG) emissions. Geothermal energy is the thermal energy stored in the underground, including any contained fluid, which is available for extraction and conversion into energy products. Electricity generation, which nowadays produces 73.7 TWh (12.7 GW of capacity) worldwide, usually requires geothermal resources temperatures of over 100 °C. For heating, geothermal resources spanning a wider range of temperatures can be used in applications such as space and district heating (and cooling, with proper technology), spa and swimming pool heating, greenhouse and soil heating, aquaculture pond heating, industrial process heating and snow melting. Produced geothermal heat in the world accounts to 164.6 TWh, with a capacity of 70.9 GW. Geothermal technology, which has focused for decades on extracting naturally heated steam or hot water from natural hydrothermal reservoirs, is developing to more advanced techniques to exploit the heat also where underground fluids are scarce and to use the Earth as a potential energy battery, by storing heat. The success of the research will enable energy recovery and utilization from a much larger fraction of the accessible thermal energy in the Earth's crust.

  6. Advanced Geothermal Turbodrill

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    W. C. Maurer

    2000-05-01

    Approximately 50% of the cost of a new geothermal power plant is in the wells that must be drilled. Compared to the majority of oil and gas wells, geothermal wells are more difficult and costly to drill for several reasons. First, most U.S. geothermal resources consist of hot, hard crystalline rock formations which drill much slower than the relatively soft sedimentary formations associated with most oil and gas production. Second, high downhole temperatures can greatly shorten equipment life or preclude the use of some technologies altogether. Third, producing viable levels of electricity from geothermal fields requires the use of largemore » diameter bores and a high degree of fluid communication, both of which increase drilling and completion costs. Optimizing fluid communication often requires creation of a directional well to intersect the best and largest number of fracture capable of producing hot geothermal fluids. Moineau motor stators made with elastomers cannot operate at geothermal temperatures, so they are limited to the upper portion of the hole. To overcome these limitations, Maurer Engineering Inc. (MEI) has developed a turbodrill that does not use elastomers and therefore can operate at geothermal temperatures. This new turbodrill uses a special gear assembly to reduce the output speed, thus allowing a larger range of bit types, especially tri-cone roller bits, which are the bits of choice for drilling hard crystalline formations. The Advanced Geothermal Turbodrill (AGT) represents a significant improvement for drilling geothermal wells and has the potential to significantly reduce drilling costs while increasing production, thereby making geothermal energy less expensive and better able to compete with fossil fuels. The final field test of the AGT will prepare the tool for successful commercialization.« less

  7. Timberland area change in the Lake States: past trends, causes, and projections.

    Treesearch

    Andrew Plantinga; Joseph Buongiorno; Ralph J. Alig; John S. Jr. Spencer

    1989-01-01

    Between the early 1960's and the mid-1980's, the area of timberland in the Lake States declined by about 3 million acres. This study confirms the influences of population, economics, ownership, and trends in other land uses on timberland area. Future declines are expected, but probably at a slower rate.

  8. Geothermic analysis of high temperature hydrothermal activities area in Western plateau of Sichuan province, China

    NASA Astrophysics Data System (ADS)

    Zhang, J.

    2016-12-01

    There is a high temperature hydrothermal activity area in the western plateau of Sichuan. More than 200 hot springs points have been found in the region, including 11 hot spring water temperature above local boiling point. Most of these distribute along Jinshajjiang fracture, Dege-Xiangcheng fracture, Ganzi-Litang fracture as well as Xianshuihe fracture, and form three high-temperature hydrothermal activity strips in the NW-SE direction. Using gravity, magnetic, seismic and helium isotope data, this paper analyzed the crust-mantle heat flow structure, crustal heat source distribution and water heating system. The results show that the geothermal activity mainly controlled by the "hot" crust. The ratio of crustal heat flow and surface heat flow is higher than 60%. In the high temperature hydrothermal activities area, there is lower S wave velocity zone with Vs<3.2 km/s in 15 30 km depth in middle and lower crust. Basing on the S wave velocity inversion temperature of crust-mantle, it has been found that there is a high temperature layer with 850 1000 ° in 20 40 km depth. It is the main heat source of high temperature hydrothermal activity area of western Sichuan. Our argument is that atmospheric precipitation, surface water infiltrated along the fault fracture into the crustal deep, heating by crustal hot source, and circulation to surface become high temperature hot water. Geothermal water mainly reserve in the Triassic strata of the containing water good carbonate rocks, and in the intrusive granite which is along the fault zone. The thermal energy of Surface heat thermal activities mainly comes from the high-temperature hot source which is located in the middle and lower crust. Being in the deep crustal fracture, the groundwater infiltrated to the deep crust and absorbed heat, then, quickly got back to the surface and formed high hot springs.

  9. Simulation and assessment of groundwater flow and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2003 through 2013: Chapter B of Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

    USGS Publications Warehouse

    Jones, Perry M.; Roth, Jason L.; Trost, Jared J.; Christenson, Catherine A.; Diekoff, Aliesha L.; Erickson, Melinda L.

    2017-09-05

    Water levels during 2003 through 2013 were less than mean water levels for the period 1925–2013 for several lakes in the northeast Twin Cities Metropolitan Area in Minnesota. Previous periods of low lake-water levels generally were correlated with periods with less than mean precipitation. Increases in groundwater withdrawals and land-use changes have brought into question whether or not recent (2003–13) lake-water-level declines are solely caused by decreases in precipitation. A thorough understanding of groundwater and surface-water exchanges was needed to assess the effect of water-management decisions on lake-water levels. To address this need, the U.S. Geological Survey, in cooperation with the Metropolitan Council and the Minnesota Department of Health, developed and calibrated a three-dimensional, steady-state groundwater-flow model representing 2003–13 mean hydrologic conditions to assess groundwater and lake-water exchanges, and the effects of groundwater withdrawals and precipitation on water levels of 96 lakes in the northeast Twin Cities Metropolitan Area.Lake-water budgets for the calibrated groundwater-flow model indicated that groundwater is flowing into lakes in the northeast Twin Cities Metropolitan Area and lakes are providing water to underlying aquifers. Lake-water outflow to the simulated groundwater system was a major outflow component for Big Marine Lake, Lake Elmo, Snail Lake, and White Bear Lake, accounting for 45 to 64 percent of the total outflows from the lakes. Evaporation and transpiration from the lake surface ranged from 19 to 52 percent of the total outflow from the four lakes. Groundwater withdrawals and precipitation were varied from the 2003‒13 mean values used in the calibrated model (30-percent changes in groundwater withdrawals and 5-percent changes in precipitation) for hypothetical scenarios to assess the effects of groundwater withdrawals and precipitation on water budgets and levels in Big Marine Lake, Snail Lake

  10. Magnetotelluric and Audio-magnetotelluric measurements in Alasehir Graben for geothermal exploration purposes

    NASA Astrophysics Data System (ADS)

    Tekesin-Cankurtaranlar, Ozge; Tuysuz, Okan; Riza Kilic, Ali

    2017-04-01

    In this study, we present the results of Magnetotelluric (MT) and Audio-magnetotelluric (AMT) soundings over a potential geothermal field. Study area is located in the northeasternmost part of the Alasehir (or Gediz) Graben, Western Anatolia, which is delimited by NW-SE trending fault systems and is filled by Miocene to Recent sediments. Study area is also very close to the Kula Quaternary volcanic region, a possible geothermal heat source for the region, last eruption of which was 12.000 years ago. Relatively thin crust, high heat flow values and intense tectonic activity of the Western Anatolia possibly refers to the high geothermal potential. In fact, along the southern and central part of the graben there are many productive areas reaching up to 300 degrees Celsius. By this motivation, to determine the geothermal potential of the study area MT and AMT measurements had been carried out on a total of 45 stations covering about 8 km2 area. All profiles shows higher resistivity values (>140 ohm.m) at greater depths, possibly indicating a metamorphic basement covered by Miocene to Recent sediments. This metamorphic basement gets shallower towards the North where the geothermally weathered schists and marbles crop out. Furthermore, a normal fault interface between metamorphic basement and Neogene sediments shows high resistivity contrast. Results indicate that the metamorphic basement is a less conductive block located at a depth of 1500 - 2000 m at the south and gets shallower towards the north as normal fault blocks.

  11. Recent Warming of Lake Kivu

    PubMed Central

    Katsev, Sergei; Aaberg, Arthur A.; Crowe, Sean A.; Hecky, Robert E.

    2014-01-01

    Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient. PMID:25295730

  12. Recent warming of lake Kivu.

    PubMed

    Katsev, Sergei; Aaberg, Arthur A; Crowe, Sean A; Hecky, Robert E

    2014-01-01

    Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient.

  13. Geomicrobiology of sublacustrine thermal vents in Yellowstone Lake: geochemical controls on microbial community structure and function

    PubMed Central

    Inskeep, William P.; Jay, Zackary J.; Macur, Richard E.; Clingenpeel, Scott; Tenney, Aaron; Lovalvo, David; Beam, Jacob P.; Kozubal, Mark A.; Shanks, W. C.; Morgan, Lisa A.; Kan, Jinjun; Gorby, Yuri; Yooseph, Shibu; Nealson, Kenneth

    2015-01-01

    Yellowstone Lake (Yellowstone National Park, WY, USA) is a large high-altitude (2200 m), fresh-water lake, which straddles an extensive caldera and is the center of significant geothermal activity. The primary goal of this interdisciplinary study was to evaluate the microbial populations inhabiting thermal vent communities in Yellowstone Lake using 16S rRNA gene and random metagenome sequencing, and to determine how geochemical attributes of vent waters influence the distribution of specific microorganisms and their metabolic potential. Thermal vent waters and associated microbial biomass were sampled during two field seasons (2007–2008) using a remotely operated vehicle (ROV). Sublacustrine thermal vent waters (circa 50–90°C) contained elevated concentrations of numerous constituents associated with geothermal activity including dissolved hydrogen, sulfide, methane and carbon dioxide. Microorganisms associated with sulfur-rich filamentous “streamer” communities of Inflated Plain and West Thumb (pH range 5–6) were dominated by bacteria from the Aquificales, but also contained thermophilic archaea from the Crenarchaeota and Euryarchaeota. Novel groups of methanogens and members of the Korarchaeota were observed in vents from West Thumb and Elliot's Crater (pH 5–6). Conversely, metagenome sequence from Mary Bay vent sediments did not yield large assemblies, and contained diverse thermophilic and nonthermophilic bacterial relatives. Analysis of functional genes associated with the major vent populations indicated a direct linkage to high concentrations of carbon dioxide, reduced sulfur (sulfide and/or elemental S), hydrogen and methane in the deep thermal ecosystems. Our observations show that sublacustrine thermal vents in Yellowstone Lake support novel thermophilic communities, which contain microorganisms with functional attributes not found to date in terrestrial geothermal systems of YNP. PMID:26579074

  14. Molecular carbon isotopic evidence for the origin of geothermal hydrocarbons

    NASA Technical Reports Server (NTRS)

    Des Marais, D. J.; Donchin, J. H.; Nehring, N. L.; Truesdell, A. H.

    1981-01-01

    Isotopic measurements of individual geothermal hydrocarbons that are, as a group, of higher molecular weight than methane are reported. It is believed in light of this data that the principal source of hydrocarbons in four geothermal areas in western North America is the thermal decomposition of sedimentary or groundwater organic matter.

  15. Movements of hatchery-reared lake trout in Lake Superior

    USGS Publications Warehouse

    Pycha, Richard L.; Dryer, William R.; King, George R.

    1965-01-01

    The history of stocking of lake trout (Salvelinus namaycush) in the Great Lakes is reviewed. The study of movements is based on capture of 24,275 fin-clipped lake trout taken in experimental gill nets and trawls and commercial gill nets. Yearling lake trout planted from shore dispersed to 15-fath (27-m) depths in 3A? hr. Most fish remained within 2 miles (3.2 km) of the planting site 2 months, but within 4 months some fish had moved as much as 17 miles (27 km). The highest abundance of planted lake trout was in areas 2-4 miles (3.2-6.4 km) from the planting site even 3 years after release. Distance moved and size of fish were not correlated. Dispersal of lake trout begins at planting and probably continues until the fish are mature. Most movement was eastward in southern Lake Superior and followed the counterclockwise surface currents. Movement is most rapid in areas of strong currents and slowest in areas of weak currents or eddies. Movement to areas west of the Keweenaw Peninsula was insignificant from plantings in Keweenaw Bay and nil from other plantings farther east. Lake trout planted in the eastern third of the lake dispersed more randomly than those planted farther west. Few fish moved farther offshore than the 50-fath (91-m) contour. Lake trout planted in Canadian waters made insignificant contributions to populations in US waters.

  16. Impact of lake breezes on ozone and nitrogen oxides in the Greater Toronto Area

    NASA Astrophysics Data System (ADS)

    Wentworth, G. R.; Murphy, J. G.; Sills, D. M. L.

    2015-05-01

    Meteorological and air quality datasets from summertime (May to September, 2010-2012) were analysed in order to assess the influence of lake-breeze circulations on pollutant levels in the Greater Toronto Area (GTA). While previous estimates of the frequency of summer days experiencing lake breezes range between 25 and 32 % for the GTA, a simple algorithm using surface meteorological observations suggested Lake Ontario breezes occurred on 56% of summer days, whereas a more reliable multiplatform approach yielded a frequency of 74%. Data from five air quality stations across the GTA were used to compare air quality on days during which a lake-breeze circulation formed ("lake breeze days") versus days when one did not ("non-lake breeze days"). Average daytime O3 maxima were 13.6-14.8 ppb higher on lake breeze days relative to non-lake breeze days. Furthermore, the Ontario Ambient Air Quality Criteria (AAQC) for 1-h average O3 (80 ppb) and 8-h average O3 (65 ppb) were exceeded only on lake breeze days and occurred on a total of 30 and 54 days throughout the study period, respectively. A causal link between lake-breeze circulations and enhanced O3 was identified by examining several days in which only some of the air quality sites were inside the lake-breeze circulation. O3 mixing ratios at sites located within the circulation were at least 30 ppb higher than sites outside the circulation, despite similar temperatures, cloud conditions and synoptic regimes across the region. Rapid O3 increases were concurrent with the arrival of the lake-breeze front, suggesting O3-rich air from over the lake is being advected inland throughout the day. Lake-breeze circulations were found to have less impact on nitrogen oxide (NOx) levels. Morning NOx was greater on lake breeze days, probably due to the stagnant conditions favourable for lake breeze formation. During the late afternoon, only inland sites experience increased NOx on lake breeze days, likely as a result of being downwind

  17. Review of historiographic aspects of geothermal energy in the Mediterranean and Mesoamerican areas prior to the Modern Age

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cataldi, R.

    1993-08-01

    This investigation aims not only to gain greater insight into the ancient uses of natural heat and its by-products, but also to gather elements for comprehending what kind of impact the presence of geothermal manifestations and the occurrence of volcanic eruptions may have produced on the ancient inhabitants of the Mediterranean and Mesoamerican regions. The first part of the paper discusses what may have occurred in the time period from the Lower Paleolithic (10[sup 5]--10[sup 6] years ago) until the end of the Neolithic. Throughout this period, the relationship of man with the various manifestations of terrestrial heat and itsmore » associated products was quite close and intense. In addition to the initial development of direct uses, this relationship with geothermal energy also involved man's cultural sphere. The second part of the paper discusses the development of direct uses and the importance that thermal balneology attained in some regions of the Mediterranean area in historical times. The exploitation and processing of hydrothermal products by the Etruscans, the blossoming of balneotherapy and the multiple functions of the spas in Roman times, the decline of all direct uses between the 5th and 6th centuries A.D. following the collapse of the Roman Empire, and the intensive exploitation of the manifestations of Larderello between the 11th and 16th centuries are discussed. The third part of the work refers to the Mesoamerican area (Mexico and neighboring regions) and covers the period extending from several millennia before the Christian era until the time of the voyages of Columbus. The last part of the paper attempts to reconstruct the birth and initial development of scientific thought regarding the various types of geothermal phenomena, starting from the oldest known illustration of a volcanic eruption until the end of the Middle Ages. 2 figs., 1 tab.« less

  18. Sanctuaries for lake trout in the Great Lakes

    USGS Publications Warehouse

    Stanley, Jon G.; Eshenroder, Randy L.; Hartman, Wilbur L.

    1987-01-01

    Populations of lake trout, severely depleted in Lake Superior and virtually extirpated from the other Great Lakes because of sea lamprey predation and intense fishing, are now maintained by annual plantings of hatchery-reared fish in Lakes Michigan, Huron, and Ontario and parts of Lake Superior. The extensive coastal areas of the Great Lakes and proximity to large populations resulted in fishing pressure on planted lake trout heavy enough to push annual mortality associated with sport and commercial fisheries well above the critical level needed to reestablish self-sustaining stocks. The interagency, international program for rehabilitating lake trout includes controlling sea lamprey abundance, stocking hatchery-reared lake trout, managing the catch, and establishing sanctuaries where harvest is prohibited. Three lake trout sanctuaries have been established in Lake Michigan: the Fox Island Sanctuary of 121, 500 ha, in the Chippewa-Ottawa Treaty fishing zone in the northern region of the lake; the Milwaukee Reef Sanctuary of 160, 000 ha in midlake, in boundary waters of Michigan and Wisconsin; and Julian's Reef Sanctuary of 6, 500 ha, in Illinois waters. In northern Lake Huron, Drummond Island Sanctuary of 55, 000 ha is two thirds in Indian treaty-ceded waters in Michigan and one third in Ontario waters of Canada. A second sanctuary, Six Fathom Bank-Yankee Reef Sanctuary, in central Lake Huron contains 168, 000 ha. Sanctuary status for the Canadian areas remains to be approved by the Provincial government. In Lake Superior, sanctuaries protect the spawning grounds of Gull Island Shoal (70, 000 ha) and Devils Island Shoal (44, 000 ha) in Wisconsin's Apostle Island area. These seven sanctuaries, established by the several States and agreed upon by the States, Indian tribes, the U.S. Department of the Interior, and the Province of Ontario, contribute toward solving an interjurisdictional fishery problem.

  19. Geothermal Energy Summary

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    J. L. Renner

    2007-08-01

    Following is complete draft.Geothermal Summary for AAPG Explorer J. L. Renner, Idaho National Laboratory Geothermal energy is used to produce electricity in 24 countries. The United States has the largest capacity (2,544 MWe) followed by Philippines (1,931 MWe), Mexico (953 MWe), Indonesia (797 MWe), and Italy (791 MWe) (Bertani, 2005). When Chevron Corporation purchased Unocal Corporation they became the leading producer of geothermal energy worldwide with projects in Indonesia and the Philippines. The U. S. geothermal industry is booming thanks to increasing energy prices, renewable portfolio standards, and a production tax credit. California (2,244 MWe) is the leading producer, followedmore » by Nevada (243 MWe), Utah (26 MWe) and Hawaii (30 MWe) and Alaska (0.4 MWe) (Bertani, 2005). Alaska joined the producing states with two 0.4 KWe power plants placed on line at Chena Hot Springs during 2006. The plant uses 30 liters per second of 75°C water from shallow wells. Power production is assisted by the availability of gravity fed, 7°C cooling water (http://www.yourownpower.com/) A 13 MWe binary power plant is expected to begin production in the fall of 2007 at Raft River in southeastern Idaho. Idaho also is a leader in direct use of geothermal energy with the state capital building and several other state and Boise City buildings as well as commercial and residential space heated using fluids from several, interconnected geothermal systems. The Energy Policy Act of 2005 modified leasing provisions and royalty rates for both geothermal electrical production and direct use. Pursuant to the legislation the Bureau of Land management and Minerals Management Service published final regulations for continued geothermal leasing, operations and royalty collection in the Federal Register (Vol. 72, No. 84 Wednesday May 2, 2007, BLM p. 24358-24446, MMS p. 24448-24469). Existing U. S. plants focus on high-grade geothermal systems located in the west. However, interest in

  20. Seasonal patterns of seismicity and deformation at the Alutu geothermal reservoir, Ethiopia, induced by hydrological loading

    NASA Astrophysics Data System (ADS)

    Birhanu, Yelebe; Wilks, Matthew; Biggs, Juliet; Kendall, J.-Michael; Ayele, Atalay; Lewi, Elias

    2018-05-01

    Seasonal variations in the seismicity of volcanic and geothermal reservoirs are usually attributed to the hydrological cycle. Here, we focus on the Aluto-Langano geothermal system, Ethiopia, where the climate is monsoonal and there is abundant shallow seismicity. We deployed temporary networks of seismometers and GPS receivers to understand the drivers of unrest. First, we show that a statistically significant peak in seismicity occurred 2-3 months after the main rainy season, with a second, smaller peak of variable timing. Seasonal seismicity is commonly attributed to variations in either surface loading or reservoir pore pressure. As loading will cause subsidence and overpressure will cause uplift, comparing seismicity rates with continuous GPS, enables us to distinguish between mechanisms. At Aluto, the major peak in seismicity is coincident with the high stand of nearby lakes and maximum subsidence, indicating that it is driven by surface loading. The magnitude of loading is insufficient to trigger widespread crustal seismicity but the geothermal reservoir at Aluto is likely sensitive to small perturbations in the stress field. Thus we demonstrate that monsoonal loading can produce seismicity in geothermal reservoirs, and the likelihood of both triggered and induced seismicity varies seasonally.

  1. Molecular carbon isotopic evidence for the origin of geothermal hydrocarbons

    USGS Publications Warehouse

    Des Marais, D.J.; Donchin, J.H.; Nehring, N.L.; Truesdell, A.H.

    1981-01-01

    Previous interest in light hydrocarbons from geothermal systems has focused principally on the origin of the methane1 and the estimation of subsurface temperatures from the carbon isotopic content of coexisting methane and carbon dioxide1-3. Higher molecular weight hydrocarbons were first reported in gases from Yellowstone National Park4, and have since been found to occur commonly in geothermal emanations in the western United States5. Isotopic measurements of individual geothermal hydrocarbons are now reported which help to explain the origin of these hydrocarbons. The thermal decomposition of sedimentary or groundwater organic matter is a principal source of hydrocarbons in four geothermal areas in western North America. ?? 1981 Nature Publishing Group.

  2. Geothermal System Extensions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gunnerson, Jon; Pardy, James J.

    This material is based upon work supported by the Department of Energy under Award Number DE-EE0000318. The City of Boise operates and maintains the nation’s largest geothermal heating district. Today, 91 buildings are connected, providing space heating to over 5.5 million square feet, domestic water heating, laundry and pool heating, sidewalk snowmelt and other related uses. Approximately 300 million gallons of 177°F geothermal water is pumped annually to buildings and institutions located in downtown Boise. The closed loop system returns all used geothermal water back into the aquifer after heat has been removed via an Injection Well. Water injected backmore » into the aquifer has an average temperature of 115°F. This project expanded the Boise Geothermal Heating District (Geothermal System) to bring geothermal energy to the campus of Boise State University and to the Central Addition Eco-District. In addition, this project also improved the overall system’s reliability and increased the hydraulic capacity.« less

  3. Construction, geologic, and hydrologic data for observation wells in the Reelfoot Lake area, Tennessee and Kentucky

    USGS Publications Warehouse

    Bradley, M.W.

    1987-01-01

    Twenty-three observation wells were installed at 12 sites in the Reelfoot Lake area of Kentucky and Tennessee during July 1986. The wells were installed to supplement an existing water level network and to provide additional data on the hydraulic characteristics and vertical hydraulic gradients in the alluvial aquifer near Reelfoot Lake. Well yields ranged from less than 20 gallons per minute to about 140 gallons per minute. The specific capacities of the wells ranged from less than 1 to 17.1 gallons per minute per foot of drawdown. Dissolved-solids concentrations ranged from 153 to 475 milligrams per liter at six wells. Three lithological sequences were encountered during drilling. Deep clay and silty clay occurred near the southwest corner of Reelfoot Lake. Predominantly medium- to coarse-grained sand occurred below about 15 feet of silt and clay near the west and northwest sides of the Lake. Along the western limit of the study area, near Lake No. 9 and the Mississippi River, at least about 50 feet of silt and silty sand occurred below land surface. (USGS)

  4. Geologic map and structure sections of the Clear Lake Volcanics, Northern California

    USGS Publications Warehouse

    Hearn, B.C.; Donnelly-Nolan, J. M.; Goff, F.E.

    1995-01-01

    The Clear Lake Volcanics are located in the California Coast Ranges about 150 km north of San Francisco. This Quaternary volcanic field has erupted intermittently since 2.1 million years ago. This volcanic field is considered a high-threat volcanic system (Ewert and others, 2005) The adjacent Geysers geothermal field, largest power-producing geothermal field in the world, is powered by the magmatic heat source for the volcanic field. This report consists of three sheets that include the geologic map, one table, two figures, three cross sections, description of map units, charts of standard and diagrammatic correlation of map units, and references. This map supersedes U.S. Geological Survey Open-File Report 76-751. Descriptions of map units are grouped by geographic area. Summaries of the evolution, chemistry, structure, and tectonic setting of the Clear Lake Volcanics are given in Hearn and others (1981) and Donnelly-Nolan and others (1981). The geology of parts of the area underlain by the Cache Formation is based on mapping by Rymer (1981); the geology of parts of the areas underlain by the Sonoma Volcanics, Franciscan assemblage, and Great Valley sequence is based on mapping by McLaughlin (1978). Volcanic compositional map units are basalt, basaltic andesite, andesite, dacite, rhyodacite, and rhyolite, based on SiO2 content. Included in this report are maps showing the distribution of volcanic rocks through time and a chart showing erupted volumes of different lava types through time. A table gives petrographic data for each map unit by mineral type, abundance, and size. Most ages are potassium-argon (K/Ar) ages determined for whole-rock samples and mineral separates by Donnelly-Nolan and others (1981), unless otherwise noted. A few ages are carbon-14 ages or were estimated from geologic relationships. Magnetic polarities are from Mankinen and others (1978; 1981) or were determined in the field by B.C. Hearn, Jr., using a portable fluxgate magnetometer

  5. Publications | Geothermal Technologies | NREL

    Science.gov Websites

    Publications Publications NREL publishes a variety of publications related to geothermal energy geothermal energy research. Featured Publications Mexico's Geothermal Market Assessment Report NREL Technical investment in the country's geothermal energy sector. Since 2013, Mexico has enacted comprehensive reforms to

  6. Geothermal Power Potential in the Tatun Volcano Group, Taiwan

    NASA Astrophysics Data System (ADS)

    Tseng, H. H.; Song, S.

    2013-12-01

    Recent energy issues have concentrated the attention on finding alternative ones. National demands for renewable and sustainable energy increase rapidly, especially the geothermal power production, which is viewed as the most potential opportunity. This study attempts to estimate the geothermal powers in the Tatung Volcano Group (TVG), Taiwan and evaluate the possibility to develop the Enhanced Geothermal System. Tatung Volcano Group is located at the northwest part of Taiwan. It has violent volcanism during 0.8-0.20Ma, and is still active with many thermal manifestations. The young volcanic activity provides the TVG with high geothermal gradient and is well suitable for exploiting geothermal resources. Many explorations on geothermal energy have been accomplished in this area during1966-1973. They included resistivity survey, magnetic prospecting, gravity method, seismic prospecting and etc. In this study, we base on previous data and apply the probabilistic volumetric method proposed by Geotherm EX Inc., modified from the approach introduced by the USGS to evaluate the geothermal power potential in TVG. Meanwhile, use a Monte Carlo simulation technique to calculate the probability distribution of potentially recoverable energy reserves. The results show that the mean value is 270Mw, and P50 is 254Mw for 30 years, separately. Furthermore, the power potential of enhanced geothermal system in TVG is also estimated by the quantitative model proposed by Massachusetts Institute of Technology (MIT 2006). The results suggest that the mean value is 3,000 MW and P50 is 2,780 MW for 30 years, separately.

  7. Honey Lake Power Facility under construction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1988-12-01

    Geothermal energy and wood waste are primary energy sources for the 30 megawatt, net, Honey Lake Power Facility, a cogeneration power plant. The facility 60% completed in January 1989, will use 1,300 tons per day of fuel obtained from selective forest thinnings and from logging residue combined with mill wastes. The power plant will be the largest industrial facility to use some of Lassen County's geothermal resources. The facility will produce 236 million kilowatt-hours of electricity annually. The plant consists of a wood-fired traveling grate furnace with a utility-type high pressure boiler. Fluids from a geothermal well will pass throughmore » a heat exchange to preheat boiler feedwater. Used geothermal fluid will be disposed of in an injection well. Steam will be converted to electrical power through a 35.5-megawatt turbine generator and transmitted 22 miles to Susanville over company-owned and maintained transmission lines. The plant includes pollution control for particulate removal, ammonia injection for removal of nitrogen oxides, and computer-controlled combustion systems to control carbon monoxide and hydrocarbons. The highly automated wood yard consists of systems to remove metal, handle oversized material, receive up to six truck loads of wood products per hour, and continuously deliver 58 tons per hour of fuel through redundant systems to ensure maximum on-line performance. The plant is scheduled to become operational in mid-1989.« less

  8. Numerical investigation of the efficiency of emission reduction and heat extraction in a sedimentary geothermal reservoir: a case study of the Daming geothermal field in China.

    PubMed

    Guo, Xuyang; Song, Hongqing; Killough, John; Du, Li; Sun, Pengguang

    2018-02-01

    The utilization of geothermal energy is clean and has great potential worldwide, and it is important to utilize geothermal energy in a sustainable manner. Mathematical modeling studies of geothermal reservoirs are important as they evaluate and quantify the complex multi-physical effects in geothermal reservoirs. However, previous modeling efforts lack the study focusing on the emission reduction efficiency and the deformation at geothermal wellbores caused by geothermal water extraction/circulation. Emission efficiency is rather relevant in geothermal projects introduced in areas characterized by elevated air pollution where the utilization of geothermal energy is as an alternative to burning fossil fuels. Deformation at geothermal wellbores is also relevant as significant deformation caused by water extraction can lead to geothermal wellbore instability and can consequently decrease the effectiveness of the heat extraction process in geothermal wells. In this study, the efficiency of emission reduction and heat extraction in a sedimentary geothermal reservoir in Daming County, China, are numerically investigated based on a coupled multi-physical model. Relationships between the efficiency of emission reduction and heat extraction, deformation at geothermal well locations, and geothermal field parameters including well spacing, heat production rate, re-injection temperature, rock stiffness, and geothermal well placement patterns are analyzed. Results show that, although large heat production rates and low re-injection temperatures can lead to decreased heat production in the last 8 years of heat extraction, they still improve the overall heat production capacity and emission reduction capacity. Also, the emission reduction capacity is positively correlated with the heat production capacity. Deformation at geothermal wellbore locations is alleviated by smaller well spacing, lower heat production rates, and smaller numbers of injectors in the well pattern, and by

  9. Development of concepts for the management of shallow geothermal resources in urban areas - Experience gained from the Basel and Zaragoza case studies

    NASA Astrophysics Data System (ADS)

    García-Gil, Alejandro; Epting, Jannis; Mueller, Matthias H.; Huggenberger, Peter; Vázquez-Suñé, Enric

    2015-04-01

    In urban areas the shallow subsurface often is used as a heat resource (shallow geothermal energy), i.e. for the installation and operation of a broad variety of geothermal systems. Increasingly, groundwater is used as a low-cost heat sink, e.g. for building acclimatization. Together with other shallow geothermal exploitation systems significantly increased groundwater temperatures have been observed in many urban areas (urban heat island effect). The experience obtained from two selected case study cities in Basel (CH) and Zaragoza (ES) has allowed developing concepts and methods for the management of thermal resources in urban areas. Both case study cities already have a comprehensive monitoring network operating (hydraulics and temperature) as well as calibrated high-resolution numerical groundwater flow and heat-transport models. The existing datasets and models have allowed to compile and compare the different hydraulic and thermal boundary conditions for both groundwater bodies, including: (1) River boundaries (River Rhine and Ebro), (2) Regional hydraulic and thermal settings, (3) Interaction with the atmosphere under consideration of urbanization and (4) Anthropogenic quantitative and thermal groundwater use. The potential natural states of the considered groundwater bodies also have been investigated for different urban settings and varying processes concerning groundwater flow and thermal regimes. Moreover, concepts for the management of thermal resources in urban areas and the transferability of the applied methods to other urban areas are discussed. The methods used provide an appropriate selection of parameters (spatiotemporal resolution) that have to be measured for representative interpretations of groundwater flow and thermal regimes of specific groundwater bodies. From the experience acquired from the case studies it is shown that understanding the variable influences of the specific geological and hydrogeological as well as hydraulic and thermal

  10. Characterization and comparison of phytoplankton in selected lakes of five Great Lakes area national parks

    USGS Publications Warehouse

    Nevers, Meredith Becker; Whitman, Richard L.

    2004-01-01

    Phytoplankton species have been widely used as indicators of lake conditions, and they may be useful for detecting changes in overall lake condition. In an attempt to inventory and monitor its natural resources, the National Park Service wants to establish a monitoring program for aquatic resources in the Great Lakes Cluster National Parks. This study sought to establish baseline information on the phytoplankton and water chemistry of selected lakes in five national parks in a preliminary effort toward establishing a long-term monitoring program. Phytoplankton and water chemistry samples were collected from ten lakes in five national parks over a two-year period. A total of 176 taxa were identified during the study. Northern lakes generally had higher Shannon-Wiener diversity and clustered together in similarity. Lakes exhibited a south to north gradient of many water chemistry variables, with northern lakes having lower hardness, sulfate, turbidity, and temperature and higher dissolved oxygen. Chloride and sulfate concentrations were the variables that best explained variation among phytoplankton in the ten lakes. A monitoring plan will have to incorporate the differences among lakes, but by coordinating the effort, comparisons within and among parks and other regions will prove useful for determining environmental change.

  11. Multidisciplinary research of geothermal modeling

    NASA Astrophysics Data System (ADS)

    -Ing. Ulvi Arslan, Univ., ., Dr. _., Prof.; Heiko Huber, Dipl.-Ing.

    2010-05-01

    KEYWORDS Geothermal sciences, geothermics, research, theory and application, numerical calculation, geothermal modeling, Technical University Darmstadt, Ministry of Economics and Technology (BMWi) INTRODUCTION In times of global warming renewable, green energies are getting more and more important. The development of application of geothermal energy as a part of renewable energies in Germany is a multidisciplinary process of fast growing research and improvements. Geothermal energy is the energy, which is stored below earth's surface. The word geothermal derives from the Greek words geo (earth) and thermos (heat), so geothermal is a synonym to earth heat. Geothermal energy is one of the auspicious renewable energies. In average the temperature increases 3°C every 100 m of depth, which is termed as geothermal gradient. Therefore 99 percent of our planet is hotter than 1.000°C, while 99 percent of that last percent is even hotter than 100°C. Already in a depth of about 1 kilometer temperatures of 35 - 40°C can be achieved. While other renewable energies arise less or more from the sun, geothermal energy sources its heat from the earth's interior, which is caused mostly by radioactive decay of persistent isotopes. This means a possibility of a base-loadable form of energy supply. Especially efficient is the use of deep geothermal energy of high-enthalpie reservoirs, which means a high energy potential in low depths. In Germany no high-enthalpie reservoirs are given. To use the given low-enthalpie potential and to generate geothermal power efficiently inventions and improvements need to be performed. An important part of geothermal progresses is performed by universities with multidisciplinary research of geothermal modeling. Especially in deep geothermal systems numerical calculations are essential for a correct dimensioning of the geothermal system. Therefore German universities and state aided organizations are developing numerical programs for a detailed use of

  12. Use of U and Th Decay-Series Disequilibrium to Characterize Geothermal Systems: An Example from the Coso Geothermal System

    NASA Astrophysics Data System (ADS)

    Leslie, B. W.; Hammond, D.

    2007-12-01

    Uranium and thorium decay series isotopes were measured in fluids and solids in the Coso geothermal system to assess the utility and constrain the limitations of the radioisotopic approach to the investigation of rock-water interaction. Fluid radioisotope measurements indicate substantial kilometer-scale variability in chemistry. Between 1988 and 1990, radium isotope activity ratios indicate temporal variability, which is exhibited by apparent mixing relationships observed as a function of time for single wells. Activity ratios of Ra-224/Ra-226 and Ra- 228/Ra-226, and the processes that contribute and remove these radionuclide to and from the fluids, constrain residence times of fluids and may help constrain fluid velocities in the geothermal system. Activity ratios of Ra- 224/Ra-226 > ten were measured. In groundwater and geothermal systems ratios of Ra-224/Ra-226 > ten are limited to zones of thermal upwelling or very young (days to weeks) waters in mountainous areas. Rn-222 results indicate that radon is also an effective tracer for steam velocities within the geothermal system. Analysis of carbon dioxide and Rn-222 data indicates that the residence time of steam (time since separation from the liquid) is short (probably less than four days). Estimates of fluid velocities derived from Rn-222 and radium isotopic measurements are within an order of magnitude of velocities derived from a fluorescein tracer test. Both Rn-222 and Ra-224 activities are higher in single-phase fluids in the northwest as compared to the southeast, indicating a higher rock-surface-area/water-volume ratio in the northwest. Thus, measurements of short-lived radioisotopes and gaseous phase constituents can constrain processes and characteristics of geothermal systems that are usually difficult to constrain (e.g., surface area/volume, residence times). The NRC staff views expressed herein are preliminary and do not constitute a final judgment or determination of the matters addressed or of

  13. Colorado Potential Geothermal Pathways

    DOE Data Explorer

    Richard E. Zehner

    2012-02-01

    This layer contains the weakened basement rocks. Isostatic gravity was utilized to identify structural basin areas, characterized by gravity low values reflecting weakened basement rocks. Together interpreted regional fault zones and basin outlines define geothermal "exploration fairways", where the potential exists for deep, superheated fluid flow in the absence of Pliocene or younger volcanic units.

  14. Subaqueous hot springs in Köyceğiz Lake, Dalyan Channel and Fethiye-Göcek Bay (SW Turkey): Locations, chemistry and origins

    NASA Astrophysics Data System (ADS)

    Avşar, Özgür; Avşar, Ulaş; Arslan, Şebnem; Kurtuluş, Bedri; Niedermann, Samuel; Güleç, Nilgün

    2017-10-01

    In this study, horizontal temperature measurements along organized grids have been used to detect subaqueous hot springs. The study area, located in the southwest of Turkey and comprised of Köyceğiz Lake, Dalyan Channel and Fethiye-Göcek Bay, was scanned by measuring temperatures horizontally, 2-3 m above the bottom of the lake or sea. After analyzing the temperature data along the grids, the locations with anomalous temperature values were detected, and divers headed here for further verification. Accordingly, among these anomalies, the divers confirmed seven of them as subaqueous hot springs. Three of these hot springs are located in the Köyceğiz Lake, three of them are located in the Dalyan Channel and one hot spring is located in the Fethiye-Göcek Bay. At the locations where temperature anomalies were detected, the divers collected samples directly from the subaqueous hot spring using a syringe-type sampler. We evaluated these water samples together with samples collected from hot and cold springs on land and from local rivers, lakes and the sea, with an aim to generate a conceptual hydrogeochemical model of the geothermal system in the study area. This model predicts that rainwater precipitating in the highlands percolates through fractures and faults into the deeper parts of the Earth's crust, here it is heated and ascends through the sea bottom via buried faults. Pervious carbonate nappes that are underlain and overlain by impervious rocks create a confined aquifer. The southern boundary of the Carbonate-Marmaris nappes is buried under alluvium and/or sea/lake water bodies and this phenomenon determines whether hot springs occur on land or subaqueous. The chemical and isotopic properties of the hot springs point to seawater mixing at deep levels. Thus, the mixing most probably occurs while the water is ascending through the faults and fractures. The gas geochemistry results reveal that the lowest mantle He contributions occur in the samples from K

  15. Exploring elements that influence stewardship in the eastern Lake Ontario dune and wetland area

    Treesearch

    Diane Kuehn; James Smahol

    2010-01-01

    Th e Eastern Lake Ontario Dune and Wetland Area (ELODWA) is a 17-mile stretch of sand dunes, wetlands, and woodlands along the eastern shore of Lake Ontario in New York State. Reductions in negative, visitor-caused impacts on the dunes (e.g., trampling of dune vegetation and sand erosion) are thought to be due in part to the extensive visitor education efforts of...

  16. Geothermal Produced Fluids: Characteristics, Treatment Technologies, and Management Options

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Finster, Molly; Clark, Corrie; Schroeder, Jenna

    2015-10-01

    Geothermal power plants use geothermal fluids as a resource and create waste residuals as part of the power generation process. Both the geofluid resource and the waste stream are considered produced fluids. The chemical and physical nature of produced fluids can have a major impact on the geothermal power industry and can influence the feasibility of geothermal power development, exploration approaches, power plant design, operating practices, and the reuse or disposal of residuals. In general, produced fluids include anything that comes out of a geothermal field and that subsequently must be managed on the surface. These fluids vary greatly dependingmore » on the geothermal reservoir being harnessed, power plant design, and the life cycle stage in which the fluid exists, but generally include water and fluids used to drill geothermal wells, fluids used to stimulate wells in enhanced geothermal systems, and makeup and/or cooling water used during operation of a geothermal power plant. Additional geothermal-related produced fluids include many substances that are similar to waste streams from the oil and gas industry, such as scale, flash tank solids, precipitated solids from brine treatment, hydrogen sulfide, and cooling-tower-related waste. This review paper aims to provide baseline knowledge on specific technologies and technology areas associated with geothermal power production. Specifically, this research focused on the management techniques related to fluids produced and used during the operational stage of a geothermal power plant; the vast majority of which are employed in the generation of electricity. The general characteristics of produced fluids are discussed. Constituents of interest that tend to drive the selection of treatment technologies are described, including total dissolved solids, noncondensable gases, scale and corrosion, silicon dioxide, metal sulfides, calcium carbonate, corrosion, metals, and naturally occurring radioactive material

  17. Geothermal Energy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Steele, B.C.; Harman, G.; Pitsenbarger, J.

    1996-02-01

    Geothermal Energy Technology (GET) announces on a bimonthly basis the current worldwide information available on the technologies required for economic recovery of geothermal energy and its use as direct heat or for electric power production.

  18. Basic overview towards the assessment of landslide and subsidence risks along a geothermal pipeline network

    NASA Astrophysics Data System (ADS)

    Astisiasari; Van Westen, Cees; Jetten, Victor; van der Meer, Freek; Rahmawati Hizbaron, Dyah

    2017-12-01

    An operating geothermal power plant consists of installation units that work systematically in a network. The pipeline network connects various engineering structures, e.g. well pads, separator, scrubber, and power station, in the process of transferring geothermal fluids to generate electricity. Besides, a pipeline infrastructure also delivers the brine back to earth, through the injection well-pads. Despite of its important functions, a geothermal pipeline may bear a threat to its vicinity through a pipeline failure. The pipeline can be impacted by perilous events like landslides, earthquakes, and subsidence. The pipeline failure itself may relate to physical deterioration over time, e.g. due to corrosion and fatigue. The geothermal reservoirs are usually located in mountainous areas that are associated with steep slopes, complex geology, and weathered soil. Geothermal areas record a noteworthy number of disasters, especially due to landslide and subsidence. Therefore, a proper multi-risk assessment along the geothermal pipeline is required, particularly for these two types of hazard. This is also to mention that the impact on human fatality and injury is not presently discussed here. This paper aims to give a basic overview on the existing approaches for the assessment of multi-risk assessment along geothermal pipelines. It delivers basic principles on the analysis of risks and its contributing variables, in order to model the loss consequences. By considering the loss consequences, as well as the alternatives for mitigation measures, the environmental safety in geothermal working area could be enforced.

  19. Analysis, Evaluation and Measures to Reduce Environmental Risk within Watershed Areas of the Eastern Zauralye District Lakes

    NASA Astrophysics Data System (ADS)

    Rasskasova, N. S.; Bobylev, A. V.; Malaev, A. V.

    2017-11-01

    The authors have performed an analysis for the use of watershed areas of the lakes of the Eastern Zauralye district (the territory to the east of Ural) for national economic purposes. The analysis gave a possibility to assess the impact of watersheds depending on the applied technologies on the dump of various runoff into the reservoir waters. The watershed areas of all lakes have been found to be actively used as pastures, farmland and recreational resources. Some of the main sources of solid and liquid industrial waste are cattle farms and agricultural land using outdated equipment and technologies. The study of 26 km of the watershed line areas showed that pollutants (household garbage, fuels and lubricants) and organic substances (phosphorus and nitrogen) got into the waters of the reservoirs. The maximum runoff of solid and liquid waste into the waters of the lakes happens in summer which leads to increased concentrations of organic substances, an increase in productivity of alga and higher aquatic flora determining the degree of eutrophication and trophy in the reservoirs. The average annual trophic status of TSI lakes of the Eastern Zauralye district is 56 which corresponds to the typical phase of eutrophy. The reduced transparency of lakes is also the evidence of an increase in biological productivity of reservoirs, their eutrophication and, as a result, the water quality deterioration. The intensive eutrophication of reservoirs, in its turn, most significantly affects the concentration of the ammonium form of nitrogen, total phosphorus and total nitrogen, increase in pH and deterioration of oxygen condition. The authors have developed various activities to reduce a technogenic risk in the watershed areas of the lakes in the Eastern Zauralye district which can be applied to other areas using the analogy method.

  20. Kenya geothermal private power project: A prefeasibility study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1992-10-01

    Twenty-eight geothermal areas in Kenya were evaluated and prioritized for development. The prioritization was based on the potential size, resource temperature, level of exploration risk, location, and exploration/development costs for each geothermal area. Suswa, Eburru and Arus are found to offer the best short-term prospects for successful private power development. It was found that cost per kill developed are significantly lower for the larger (50MW) than for smaller-sized (10 or 20 NW) projects. In addition to plant size, the cost per kill developed is seen to be a function of resource temperature, generation mode (binary or flash cycle) and transmissionmore » distance.« less

  1. Geothermal Reservoir Temperatures in Southeastern Idaho using Multicomponent Geothermometry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Neupane, Ghanashyam; Mattson, Earl D.; McLing, Travis L.

    Southeastern Idaho exhibits numerous warm springs, warm water from shallow wells, and hot water within oil and gas test wells that indicate a potential for geothermal development in the area. Although the area exhibits several thermal expressions, the measured geothermal gradients vary substantially (19 – 61 ºC/km) within this area, potentially suggesting a redistribution of heat in the overlying ground water from deeper geothermal reservoirs. We have estimated reservoir temperatures from measured water compositions using an inverse modeling technique (Reservoir Temperature Estimator, RTEst) that calculates the temperature at which multiple minerals are simultaneously at equilibrium while explicitly accounting for themore » possible loss of volatile constituents (e.g., CO2), boiling and/or water mixing. Compositions of a selected group of thermal waters representing southeastern Idaho hot/warm springs and wells were used for the development of temperature estimates. The temperature estimates in the the region varied from moderately warm (59 ºC) to over 175 ºC. Specifically, hot springs near Preston, Idaho resulted in the highest temperature estimates in the region.« less

  2. Geothermal fields of China

    NASA Astrophysics Data System (ADS)

    Kearey, P.; HongBing, Wei

    1993-08-01

    There are over 2500 known occurrences of geothermal phenomena in China. These lie mainly in four major geothermal zones: Xizang (Tibet)-Yunnan, Taiwan, East Coast and North-South. Hot water has also been found in boreholes in major Mesozoic-Cenozoic sedimentary basins. This paper presents a summary of present knowledge of these geothermal zones. The geological settings of geothermal occurrences are associated mainly with magmatic activity, fault uplift and depressional basins and these are described by examples of each type. Increased multipurpose utilisation of geothermal resources is planned and examples are given of current usages.

  3. Topographic map analysis to determine Arjuno-Welirang volcanostratigraphy and implication for geothermal exploration

    NASA Astrophysics Data System (ADS)

    Apriani, Lestari; Satriana, Joshua; Aulian Chalik, Citra; Syahputra Mulyana, Reza; Hafidz, Muhammad; Suryantini

    2017-12-01

    Volcanostratigraphy study is used for supporting geothermal exploration on preliminary survey. This study is important to identify volcanic eruption center which shows potential area of geothermal heat source. The purpose of volcanostratigraphy study in research area is going to distinguish the characteristics of volcanic eruption product that construct the volcanic body. The analysis of Arjuno-Welirang volcanostratigraphy identification are based on topographic maps of Malang sheet with 1:100.000 scale, 1:50.000 scale, and a geological map. Regarding to the delineation of ridge and river, we determine five crowns, three hummocks, one brigade and one super brigade. The crowns consist of Ringgit, Welirang, Arjuno, Kawi, and Penanggungan, the hummocks comprise of Kembar III, Kembar II, and Kembar I, the brigade is Arjuno-Welirang, and the super brigade is Tengger. Based on topographic map interpretation and geothermal prospect evaluation method analysis, shows that Arjuno-Welirang prospect area have good geothermal resource potential.

  4. GEOTHERMAL / SOLAR HYBRID DESIGNS: USE OF GEOTHERMAL ENERGY FOR CSP FEEDWATER HEATING

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Craig Turchi; Guangdong Zhu; Michael Wagner

    2014-10-01

    This paper examines a hybrid geothermal / solar thermal plant design that uses geothermal energy to provide feedwater heating in a conventional steam-Rankine power cycle deployed by a concentrating solar power (CSP) plant. The geothermal energy represents slightly over 10% of the total thermal input to the hybrid plant. The geothermal energy allows power output from the hybrid plant to increase by about 8% relative to a stand-alone CSP plant with the same solar-thermal input. Geothermal energy is converted to electricity at an efficiency of 1.7 to 2.5 times greater than would occur in a stand-alone, binary-cycle geothermal plant usingmore » the same geothermal resource. While the design exhibits a clear advantage during hybrid plant operation, the annual advantage of the hybrid versus two stand-alone power plants depends on the total annual operating hours of the hybrid plant. The annual results in this draft paper are preliminary, and further results are expected prior to submission of a final paper.« less

  5. Radon and temperature as tracer of geothermal flow system: application to Arxan geothermal system, Northeastern China

    NASA Astrophysics Data System (ADS)

    Gu, X.; Shao, J.; Cui, Y.

    2017-12-01

    In this work, hydrogeological and hydrochemical investigations were applied to explain geothermal system factors controlling groundwater mineralization in Arxan geothermal system, Northeastern China. Geothermal water samples were collected from different locations (thermal baths and wells). Radon concentrations of water samples representing different water types and depths were controlled using RAD7. In addition to radon concentration, physical parameters such as temperature (T), pH, electrical conductivity (EC) and TDS were measured in situ, while major ions were analyzed in laboratory. Temperature spatial variability in the study area was described using kriging interpolation method. Hydrochemical analysis and thermal parameters suggest two distinct hydrogeological systems. The first type was dominated by a moderate temperature (25 41°C) with a chemical facies Na-HCO3, which characterizes Jurassic deep water. The second water type was characterized by Ca.Na-HCO3 type with a temperature <25 °C and represents the shallow aquifer. Superficial aquifer displays higher radon concentration (37 to 130 Bq/L), while deep groundwater from Jurassic aquifer shows relatively a low radon concentration (6 to 57.4 Bq/L). Seasonal and geographical variations of radon give insight into the processes controlling radon activities in the Arxan groundwater. Radon concentrations along with spatial distribution of water temperature reveal the existence of vertical communication between shallow aquifer and deep Jurassic aquifer through vertical faults and fractures system, the emanation of radon from thermal water and groundwater is controlled by the geological structure of the area. Furthermore, the knowledge and conclusion demonstrates that combined use of radon and temperature as tracers can give insight into the characteristics of geological structure and geothermal flow system.

  6. Ikaite precipitation by mixing of shoreline springs and lake water, Mono Lake, California, USA

    NASA Astrophysics Data System (ADS)

    Bischoff, James L.; Stine, Scott; Rosenbauer, Robert J.; Fitzpatrick, John A.; Stafford, Thomas W., Jr.

    1993-08-01

    Metastable ikaite (CaCO 3·6H 2O) forms abundantly during winter months along the south shoreline of Mono Lake where shoreline springs mix with lake water. Ikaite precipitates because of its decreased solubility at low temperature and because of orthophosphate-ion inhibition of calcite and aragonite. During the spring some of the ikaite is transformed to anhydrous CaCO 3 and is incorporated into tufa, but most is dispersed by wave action into the lake where it reacts to form gaylussite (Na 2Ca(CO 3) 2· 5H 2O). Spring waters have low pH values, are dominantly Ca-Na-HCO 3, have low radiocarbon activities, and are mixtures of deep-seated geothermal and cold groundwaters. Chemical modeling reveals that precipitation of CaCO 3 can occur over a broad range of mixtures of spring and lake water with a maximum production occurring at 96% spring water and 4% lake water. Under these conditions all the Ca and a significant fraction of the CO 3 of the precipitate is spring supplied. A radiocarbon age of 19,580 years obtained on a natural ikaite sample supports this conclusion. With the springs supplying a large and probably variable portion of the carbonate, and with apparent 14C age of the carbonate varying from spring to spring, tufa of similar actual antiquity may yield significantly different 14C dates, making tufa at this location unsuitable for absolute age dating by the radiocarbon method.

  7. Ikaite precipitation by mixing of shoreline springs and lake water, Mono Lake, California, USA

    USGS Publications Warehouse

    Bischoff, J.L.; Stine, S.; Rosenbauer, R.J.; Fitzpatrick, J.A.; Stafford, Thomas W.

    1993-01-01

    Metastable ikaite (CaCO3??6H2O) forms abundantly during winter months along the south shoreline of Mono Lake where shoreline springs mix with lake water. Ikaite precipitates because of its decreased solubility at low temperature and because of orthophosphate-ion inhibition of calcite and aragonite. During the spring some of the ikaite is transformed to anhydrous CaCO3 and is incorporated into tufa, but most is dispersed by wave action into the lake where it reacts to form gaylussite (Na2Ca(CO3)2?? 5H2O). Spring waters have low pH values, are dominantly Ca-Na-HCO3, have low radiocarbon activities, and are mixtures of deep-seated geothermal and cold groundwaters. Chemical modeling reveals that precipitation of CaCO3 can occur over a broad range of mixtures of spring and lake water with a maximum production occurring at 96% spring water and 4% lake water. Under these conditions all the Ca and a significant fraction of the CO3 of the precipitate is spring supplied. A radiocarbon age of 19,580 years obtained on a natural ikaite sample supports this conclusion. With the springs supplying a large and probably variable portion of the carbonate, and with apparent 14C age of the carbonate varying from spring to spring, tufa of similar actual antiquity may yield significantly different 14C dates, making tufa at this location unsuitable for absolute age dating by the radiocarbon method. ?? 1993.

  8. Geothermal systems: Principles and case histories

    NASA Astrophysics Data System (ADS)

    Rybach, L.; Muffler, L. J. P.

    The classification of geothermal systems is considered along with the geophysical and geochemical signatures of geothermal systems, aspects of conductive heat transfer and regional heat flow, and geothermal anomalies and their plate tectonic framework. An investigation of convective heat and mass transfer in hydrothermal systems is conducted, taking into account the mathematical modelling of hydrothermal systems, aspects of idealized convective heat and mass transport, plausible models of geothermal reservoirs, and preproduction models of hydrothermal systems. Attention is given to the prospecting for geothermal resources, the application of water geochemistry to geothermal exploration and reservoir engineering, heat extraction from geothermal reservoirs, questions of geothermal resource assessment, and environmental aspects of geothermal energy development. A description is presented of a number of case histories, taking into account the low enthalpy geothermal resource of the Pannonian Basin in Hungary, the Krafla geothermal field in Northeast Iceland, the geothermal system of the Jemez Mountains in New Mexico, and extraction-reinjection at the Ahuachapan geothermal field in El Salvador.

  9. Diversity and abundance of the arsenite oxidase gene aioA in geothermal areas of Tengchong, Yunnan, China.

    PubMed

    Jiang, Zhou; Li, Ping; Jiang, Dawei; Wu, Geng; Dong, Hailiang; Wang, Yanhong; Li, Bing; Wang, Yanxin; Guo, Qinghai

    2014-01-01

    A total of 12 samples were collected from the Tengchong geothermal areas of Yunnan, China, with the goal to assess the arsenite (AsIII) oxidation potential of the extant microbial communities as inferred by the abundance and diversity of the AsIII oxidase large subunit gene aioA relative to geochemical context. Arsenic concentrations were higher (on average 251.68 μg/L) in neutral or alkaline springs than in acidic springs (on average 30.88 μg/L). aioA abundance ranged from 1.63 × 10(1) to 7.08 × 10(3) per ng of DNA and positively correlated with sulfide and the ratios of arsenate (AsV):total dissolved arsenic (AsTot). Based on qPCR estimates of bacterial and archaeal 16S rRNA gene abundance, aioA-harboring organisms comprised as much as ~15% of the total community. Phylogenetically, the major aioA sequences (270 total) in the acidic hot springs (pH 3.3-4.4) were affiliated with Aquificales and Rhizobiales, while those in neutral or alkaline springs (pH 6.6-9.1) were inferred to be primarily bacteria related to Thermales and Burkholderiales. Interestingly, aioA abundance at one site greatly exceeded bacterial 16S rRNA gene abundance, suggesting these aioA genes were archaeal even though phylogenetically these aioA sequences were most similar to the Aquificales. In summary, this study described novel aioA sequences in geothermal features geographically far removed from those in the heavily studied Yellowstone geothermal complex.

  10. Estimating the Prospectivity of Geothermal Resources Using the Concept of Hydrogeologic Windows

    NASA Astrophysics Data System (ADS)

    Bielicki, Jeffrey; Blackwell, David; Harp, Dylan; Karra, Satish; Kelley, Richard; Kelley, Shari; Middleton, Richard; Person, Mark; Sutula, Glenn; Witcher, James

    2016-04-01

    In this Geothermal Play Fairways Analysis project we sought to develop new ways to analyze geologic, geochemical, and geophysical data to reduce the risk and increase the prospects of successful geothermal exploration and development. We collected, organized, and analyzed data from southwest New Mexico in the context of an integrated framework that combines the data for various signatures of a geothermal resource into a cohesive analysis of the presence of heat, fluid, and permeability. We incorporated data on structural characteristics (earthquakes, geophysical logs, fault location and age, basement depth), topographic and water table elevations, conservative ion concentrations, and thermal information (heat flow, bottom hole temperature, discharge temperature, and basement heat generation). These data were combined to create maps that indicate structural analysis, slope, geothermometry, and heat. We also mapped discharge areas (to constrain elevations where groundwater may be discharged through modern thermal springs or paleo-thermal springs) and subcrops: possible erosionally- or structurally-controlled breaches in regional-scale aquitards that form the basis of our hydrogeologic windows concept. These two maps were particularly useful in identifying known geothermal systems and narrowing the search for unknown geothermal prospects. We further refined the "prospectivity" of the areas within the subcrops and discharge areas by developing and applying a new method for spatial association analysis to data on known and inferred faults, earthquakes, geochemical thermometers, and heat flow. This new methodology determines the relationships of the location and magnitudes of observations of these data with known geothermal sites. The results of each of the six spatial association analyses were weighted between 0 and 1 and summed to produce a prospectivity score between 0 and 6, with 6 indicating highest geothermal potential. The mean value of prospectivity for all

  11. Statistical analysis of lake levels and field study of groundwater and surface-water exchanges in the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015: Chapter A of Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

    USGS Publications Warehouse

    Jones, Perry M.; Trost, Jared J.; Diekoff, Aliesha L.; Rosenberry, Donald O.; White, Eric A.; Erickson, Melinda L.; Morel, Daniel L.; Heck, Jessica M.

    2016-10-19

    Water levels declined from 2003 to 2011 in many lakes in Ramsey and Washington Counties in the northeast Twin Cities Metropolitan Area, Minnesota; however, water levels in other northeast Twin Cities Metropolitan Area lakes increased during the same period. Groundwater and surface-water exchanges can be important in determining lake levels where these exchanges are an important component of the water budget of a lake. An understanding of groundwater and surface-water exchanges in the northeast Twin Cities Metropolitan Area has been limited by the lack of hydrologic data. The U.S. Geological Survey, in cooperation with the Metropolitan Council and Minnesota Department of Health, completed a field and statistical study assessing lake-water levels and regional and local groundwater and surface-water exchanges near northeast Twin Cities Metropolitan Area lakes. This report documents the analysis of collected hydrologic, water-quality, and geophysical data; and existing hydrologic and geologic data to (1) assess the effect of physical setting and climate on lake-level fluctuations of selected lakes, (2) estimate potential percentages of surface-water contributions to well water across the northeast Twin Cities Metropolitan Area, (3) estimate general ages for waters extracted from the wells, and (4) assess groundwater inflow to lakes and lake-water outflow to aquifers downgradient from White Bear Lake. Statistical analyses of lake levels during short-term (2002–10) and long-term (1925–2014) periods were completed to help understand lake-level changes across the northeast Twin Cities Metropolitan Area. Comparison of 2002–10 lake levels to several landscape and geologic characteristics explained variability in lake-level changes for 96 northeast Twin Cities Metropolitan Area lakes. Application of several statistical methods determined that (1) closed-basin lakes (without an active outlet) had larger lake-level declines than flow-through lakes with an outlet; (2

  12. Geothermal Maps | Geospatial Data Science | NREL

    Science.gov Websites

    presented in these maps was aggregated from the Geothermal Energy Association 2014 Annual U.S. and Global Geothermal Maps Geothermal Maps Our geothermal map collection covers U.S. geothermal power plants , geothermal resource potential, and geothermal power generation. If you have difficulty accessing these maps

  13. Philippine geothermal resources: General geological setting and development

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Datuin, R.T.; Troncales, A.C.

    1986-01-01

    The Phillippine Archipelago has a composite geologic structure arising from the multi-stage development of volcanic-tectonic events evidenced by volcanism and seismic activity occurring along the active blocks of the major structural lines which traverse most of the major islands of the Phillipines. The widespread volcanic activity located along the active tectonic block has generated regions of high heat flow, where a vast number of potential rich geothermal resources could be exploited as an alternative source of energy. As part of a systematic geothermal development program launched by the Philippine government after the successful pilot study at the Tiwi geothermal fieldmore » in 1967 by the Commission on Volcanology (now called the Philippine Institute of Volcanology-PIV), the Philippines developed four geothermal fields in the period 1972-84. These four areas, Tiwi in Albay, Mak-Ban in Laguna, Tongonan in Leyte, and Palinpinon in Southern Negros, have already contributed 891 MW installed capacity to the total electrical power supply of the country, which is mainly dependent on oil resources. The Philippines envisaged that, with its accelerated geothermal energy programme, it would be able to achieve its target of reducing the country's dependence on imported fossil fuel by about 20% within the next decade through the utilization of its vast geothermal energy resources.« less

  14. Fracture Characterization in the Astor Pass Geothermal Field, Nevada

    NASA Astrophysics Data System (ADS)

    Walsh, D. C.; Reeves, D. M.; Pohll, G.; Lyles, B. F.; Cooper, C. A.

    2011-12-01

    The Astor Pass geothermal field, near Pyramid Lake, NV, is under study as a site of potential geothermal energy production. Three wells have been completed in the graben of this typical Basin and Range geologic setting. Lithologies include a layer of unconsolidated sediment (basin fill) underlain by various tertiary volcanic units and granodiorite and metavolcanic basement rock. Characterization of fractures within the relatively impermeable rock matrix is being conducted for the three wells. Statistical analysis of fracture orientation, densities, and spacing obtained from borehole imaging logs is used to determine stress orientation and to generate a statistically equivalent Discrete Fracture Network (DFN) model. Fractures at depth are compared to fracture data collected in nearby outcrops of the same lithologic stratigraphy. Fracture geometry and density is correlated to mechanically discrete layers within the stratigraphy to test whether variations in fracturing can be attributed to variations in Young's modulus. Correlation of fracture geometry and densities with spinner flowmeter logs and distributed temperature sensor records are made in an effort to identify potential flowing fracture zones intersecting the borehole. Mean fracture aperture is obtained from open fracture counts and reservoir-scale transmissivity values (computed from a 30 day pump test) in the absence of readily available aperture data. The goal of this thorough fracture characterization is to create a physically relevant model which may be coupled with a multipurpose fluid flow and thermal simulator for investigation of geothermal reservoir behavior, particularly at the borehole scale.

  15. Helium and Neon in the Accreted Ice of the Subglacial Antarctic Lake Vostok

    NASA Astrophysics Data System (ADS)

    Jean-Baptiste, P.; Fourré, E.; Petit, J. R.; Lipenkov, V.; Bulat, S.; Chetverikov, Y.; Raynaud, D.

    2018-05-01

    We analyzed helium and neon in 24 samples from between 3,607 and 3,767 m (i.e., down to 2 m above the lake-ice interface) of the accreted ice frozen to the ceiling of Lake Vostok. Within uncertainties, the neon budget of the lake is balanced, the neon supplied to the lake by the melting of glacier ice being compensated by the neon exported by lake ice. The helium concentration in the lake is about 12 times more than in the glacier ice, with a measured 3He/4He ratio of 0.12 ± 0.01 Ra. This shows that Lake Vostok's waters are enriched by a terrigenic helium source. The 3He/4He isotope ratio of this helium source was determined. Its radiogenic value (0.057 × Ra) is typical of an old continental province, ruling out any magmatic activity associated with the tectonic structure of the lake. It corresponds to a low geothermal heat flow estimated at 51 mW/m2.

  16. Landslide susceptibility in the Tully Valley area, Finger Lakes region, New York

    USGS Publications Warehouse

    Jager, Stefan; Wieczorek, Gerald E.

    1994-01-01

    As a consequence of a large landslide in the Tully Valley, Onondaga County, New York, an investigation was undertaken to determine the factors responsible for the landslide in order to develop a model for regional landslide susceptibility. The April 27, 1993 Tully Valley landslide occurred within glacial lake clays overlain by till and colluvium on gentle slopes of 9-12 degrees. The landslide was triggered by extreme climatic events of prolonged heavy rainfall combined with rapid melting of a winter snowpack. A photoinventory and field checking of landslides within a 415 km2 study area, including the Tully Valley, revealed small recently-active landslides and other large dormant prehistoric landslides, probably Pleistocene in age. Similar to the larger Tully Valley landslide, the smaller recently-active landslides occurred in red, glacial lake clays very likely triggered by seasonal rainfall. The large dormant landslides have been stable for long periods as evidenced by slope denudational processes that have modified the landslides. These old and ancient landslides correspond with proglacial lake levels during the Pleistocene, suggesting that either inundation or rapid drainage was responsible for triggering these landslides. A logistic regression analysis was performed within a Geographic Information System (GIS) environment to develop a model of landslide susceptibility for the Tully Valley study area. Presence of glacial clays, slope angle, and glacial lake levels were used as explanatory variables for landslide incidence. The spatial probability of landsliding, categorized as low, moderate and high, is portrayed within 90-m square cells on the susceptibility map.

  17. Geothermal Energy Basics | NREL

    Science.gov Websites

    Geothermal Energy Basics Geothermal Energy Basics Many technologies have been developed to take advantage of geothermal energy-the heat from the earth. This heat can be drawn from several sources: hot hot spring. The Earth's heat-called geothermal energy-escapes as steam at a hot springs in Nevada

  18. Geothermal Energy.

    ERIC Educational Resources Information Center

    Reed, Marshall J.

    1979-01-01

    During 1978, exploration for geothermal energy continued at the same moderately low level of the past few years in most countries. The U.S. is the only country where the development of geothermal energy depends on private industry. (BB)

  19. The NSF/RANN FY 1975 program for geothermal resources research and technology

    NASA Technical Reports Server (NTRS)

    Kruger, P.

    1974-01-01

    The specific goal of the NSF geothermal program is the rapid development by industry of the nation's geothermal resources that can be demonstrated to be commercially, environmentally and socially acceptable as alternate energy sources. NSF, as the lead agency for the federal geothermal energy research program, is expediting a program which encompasses the objectives necessary for significant utilization. These include: acceleration of exploration and assessment methods to identify commercial geothermal resources; development of innovative and improved technology to achieve economic feasibility; evaluation of policy options to resolve environmental, legal, and institutional problems; and support of experimental research facilities for each type of geothermal resource. Specific projects in each of these four objective areas are part of the NSF program for fiscal year 1975.

  20. Market study for direct utilization of geothermal resources by selected sectors of economy

    NASA Astrophysics Data System (ADS)

    1980-08-01

    A comprehensive analysis is presented of industrial markets potential for direct use of geothermal energy by a total of six industry sectors: food and kindred products; tobacco manufactures; textile mill products; lumber and wood products (except furniture); chemicals and allied products; and leather and leather products. Location determinants and potential for direct use of geothermal resources are presented. The data was gathered through interviews with 30 senior executives in the six sectors of economy selected for study. Probable locations of plants in geothermal resource areas and recommendations for geothermal resource marketing are presented.

  1. Geothermal research and development program of the US Atomic Energy Commission

    NASA Technical Reports Server (NTRS)

    Werner, L. B.

    1974-01-01

    Within the overall federal geothermal program, the Atomic Energy Commission has chosen to concentrate on development of resource utilization and advanced research and technology as the areas most suitable to the expertise of its staff and that of the National Laboratories. The Commission's work in geothermal energy is coordinated with that of other agencies by the National Science Foundation, which has been assigned lead agency by the Office of Management and Budget. The objective of the Commission's program, consistent with the goals of the total federal program is to facilitate, through technological advancement and pilot plant operations, achievement of substantial commercial production of electrical power and utilization of geothermal heat by the year 1985. This will hopefully be accomplished by providing, in conjunction with industry, credible information on the economic operation and technological reliability of geothermal power and use of geothermal heat.

  2. The Impact of Eutrophication on Mercury Cycling in Lake 227 at the Experimental Lakes Area in Northwestern Ontario

    NASA Astrophysics Data System (ADS)

    Kirk, J.; Lehnherr, I.; Gleason, A.; St. Louis, V. L.; Muir, D.

    2012-12-01

    Mercury (Hg) is a pollutant of global concern as concentrations of methyl mercury (MeHg), the toxic and bioaccumulative form of Hg, are often present in fish at levels high enough to pose health risks to consumers. Although we are beginning to understand the factors controlling MeHg production in freshwater lakes, the impacts of environmental disturbances, such as eutrophication, on Hg cycling are not known. As part of a larger project examining controls on eutrophication, we are studying Hg cycling and MeHg production in the artificially eutrophied Lake 227 at the Experimental Lakes Area in northwestern Ontario. In addition to 40 years of ancillary data, Lake 227 is ideal for this study as it has an anoxic hypolimnion which may be an important zone of microbial MeHg production. To determine sources and losses of inorganic Hg(II) and MeHg from the lake, we are using a mass balance approach including: detailed lake profiles to determine the water column pools of Hg(II) and MeHg, Hg(II) and MeHg inputs via precipitation, and losses of Hg(II) and MeHg from the lake via gaseous elemental Hg(0) evasion and MeHg photodemethylation, respectively. Rates of water column MeHg production are also being determined using Hg stable isotope tracer experiments. 2010-2011 water column profiles demonstrated that although total Hg (THg) and MeHg concentrations were fairly low in Lake 227 surface waters (2.42 ± 0.64 and 0.11 ± 0.06 ng/L, respectively), MeHg concentrations (1.08 ± 0.39 ng/L) and the % THg that was MeHg (16 ± 5%) were high in deep regions of the water column (6-9 m). The zone of elevated water column MeHg expanded throughout summers 2010-2011, closely following the zone of anoxia, suggesting MeHg is produced in the anoxic hypolimnion. The zone of high particulate-bound THg (62 ± 6%) also migrated with the zone of anoxia over the summer suggesting that particle sinking and sediment resuspension, which are controlled by the timing of algal blooms, are important

  3. Novel approaches for an enhanced geothermal development of residential sites

    NASA Astrophysics Data System (ADS)

    Schelenz, Sophie; Firmbach, Linda; Shao, Haibing; Dietrich, Peter; Vienken, Thomas

    2015-04-01

    An ongoing technological enhancement drives an increasing use of shallow geothermal systems for heating and cooling applications. However, even in areas with intensive shallow geothermal use, planning of geothermal systems is in many cases solely based on geological maps, drilling databases, and literature references. Thus, relevant heat transport parameters are rather approximated than measured for the specific site. To increase the planning safety and promote the use of renewable energies in the domestic sector, this study investigates a novel concept for an enhanced geothermal development of residential neighbourhoods. This concept is based on a site-specific characterization of subsurface conditions and the implementation of demand-oriented geothermal usage options. Therefore, an investigation approach has been tested that combines non-invasive with minimum-invasive exploration methods. While electrical resistivity tomography has been applied to characterize the geological subsurface structure, Direct Push soundings enable a detailed, vertical high-resolution characterization of the subsurface surrounding the borehole heat exchangers. The benefit of this site-specific subsurface investigation is highlighted for 1) a more precise design of shallow geothermal systems and 2) a reliable prediction of induced long-term changes in groundwater temperatures. To guarantee the financial feasibility and practicability of the novel geothermal development, three different options for its implementation in residential neighbourhoods were consequently deduced.

  4. Lake surface area variation and its responses to climatic change in Yamzhog Yumco Basin, South Tibet during 1970-2010

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Tian, Y.; Sun, R.

    2015-12-01

    The research on lake extraction from multi-source and multi-temporal satellite images and the lake size variation can provide reliable method and indispensable information to deepen the understanding about alpine lake changes with the accelerating warming. With field survey experience in the Yamzhog Yumco Basin, South Tibet, the outlines of five lakes (i.e., Yamzhog Yumco, Chen Co, Kongmu Co, Bajiu Co and Puma Yumco) were delineated by the adoption of 42 scenes of satellite images from Landsat, CBERS and HJ from 1970 to 2010, basing on which the responses of alpine lakes to climate change at different timescales were explored. The results are summarized as follows. (1) The seasonal fluctuation of lake surface area was similar with different trend for the five alpine lakes. As for the last 41 years, the annual variation of lake surface area exhibited two kinds of patterns for the five alpine lakes. And the Yamzhog Yumco declined by 9.41%, while the rest four lakes expanded. (2) The responses of alpine lakes to climate change rely on different timescale and water replenishment types. On the one hand, the precipitation change was the predominant driving forces for the seasonal fluctuation and variation trend of lake size, and the rising temperature accounted for the inter-annual lake surface variation. On the other hand, the two kinds of alpine lakes behaviors were well correspondent with the warming temperature over the Qinghai-Tibetan Plateau. The lakes supplied mainly by precipitation shrunk as a result of increased evaporation, and lakes supplied mainly by glacier and snow meltwater, however, expanded because of the remarkable glacier recession. (3) The quantification of hydrological components would hopefully be improved, according to uncertainties analysis, with the adoption of microwave satellite images and higher resolution ones to disclose the interaction mechanism among climate, glacier, and lake in alpine regions.

  5. Preliminary tephra-fall records from three lakes in the Anchorage, Alaska area: advances towards a regional tephrochronostratigraphic framework

    NASA Astrophysics Data System (ADS)

    Wallace, K. L.; Kaufman, D. S.; Schiff, C. J.; Kathan, K.; Werner, A.; Hancock, J.; Hagel, L. A.

    2010-12-01

    Sediment cores recovered from three kettle lakes, all within 10 km of Anchorage, Alaska contain a record of tephra fall from major eruptive events of Cook Inlet volcanoes during the past 11250 yr. Prominent tephra layers from multiple cores within each lake were first correlated within each basin using physical properties, major-oxide glass geochemistry, and constrained by bracketing radiocarbon age. Distinct tephra from each lake were then correlated among all three lakes using the same criteria to develop a composite tephrostratigraphic framework for the Anchorage area. Lorraine Lake, the northern-most lake contains 17 distinct tephra layers; Goose Lake, the eastern most lake contains 10 distinct tephra layers; and Little Campbell Lake, to the west, contains 7 distinct tephra layers. Thinner, less-prominent tephra layers, reflecting smaller or more distant eruptions, also occur but are not included as part of this study. Of the 33 tephra layers, only two could be confidently correlated among all three lakes, and four other correlative deposits were recognized in two of the three lakes. The minimum number of unique major tephra-fall events in the Anchorage area is 22 in the past 11200 years, or about 1 event every 500 years. This number underestimates the actual number of eruptions because not attempt was made to locate crypto-tephra. All but perhaps one tephra deposit originated from Cook Inlet volcanoes with the most prolific source being Mount Spurr/Crater Peak, which is accountable for at least 8 deposits. Combining radiocarbon ages to produce an independent age model for each lake is in progress and will aid in confirming correlations and assigning detailed modeled-tephra age and uncertainty to each tephra layer.

  6. Holocene pollen and sediment record from the tangle lakes area, central Alaska

    USGS Publications Warehouse

    Ager, Thomas A.; Sims, John D.

    1981-01-01

    Pollen and sediments have been analyzed from a 5.5 meter‐length core of lacustrine sediments from Tangle Lakes, in the Gulkana Upland south of the Alaska Range (63 ° 01 ‘ 46”; N. latitude, 146° 03 ‘ 48 “ W. longitude). Radiocarbon ages indicate that the core spans the last 4700 years. The core sediments are sandy silt and silty clay; the core shows distinct rhythmic laminations in the lower 398 cm. The laminae appear to be normally graded; peat fibers and macerated plant debris are more abundant near the tops of the laminae. Six volcanic‐ash layers are present in the upper 110 cm of the core.Present‐day vegetation of the Tangle Lakes area is mesic shrub tundra and open spruce woodland, with scattered patches of shrub willow (Salix), balsam poplar (P. balsamifera), spruce (Picea), paper birch (Betula papyrifera), and alder (Alnus). Pollen analysis of 27 core samples suggests that this vegetation type has persisted throughout the past 4700 years, except for an apparently substantial increase in Picea beginning about 3500 years B.P. Percentages of Picea pollen are very low (generally 1–3 percent) in the lower 2 meters of core (ca. 4700 to 3500 years B.P.), but rise to 13–18 percent in the upper 3.4 meters (ca. 3500 years B.P. to present). Previously reported data from this area indicate that Picea trees initially arrived in the Tangle Lakes area about 9100 years B.P., at least 2.5 to 3 thousand years after deglaciation of the region. The present investigation suggests that Picea trees became locally scarce or died out sometime after about 9000 years B.P. but before 4700 years B.P., then reinvaded the area about 3500 years B.P. If this extrapolated age for the Picea reinvasion is accurate it suggests that local expansion of the Picea population coincides with the onset of a Neoglacial interval of cooler, moister climate. This is an unexpected result, because intervals of cooler climate generally coincide with lowering of the altitudinal limit of

  7. "Assistance to States on Geothermal Energy"

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Linda Sikkema; Jennifer DeCesaro

    2006-07-10

    This final report summarizes work carried out under agreement with the U.S. Department of Energy, related to geothermal energy policy issues. This project has involved a combination of outreach and publications on geothermal energy—Contract Number DE-FG03-01SF22367—with a specific focus on educating state-level policymakers. Education of state policymakers is vitally important because state policy (in the form of incentives or regulation) is a crucial part of the success of geothermal energy. State policymakers wield a significant influence over all of these policies. They are also in need of high quality, non-biased educational resources which this project provided. This project provided outreachmore » to legislatures, in the form of responses to information requests on geothermal energy and publications. The publications addressed: geothermal leasing, geothermal policy, constitutional and statutory authority for the development of geothermal district energy systems, and state regulation of geothermal district energy systems. These publications were distributed to legislative energy committee members, and chairs, legislative staff, legislative libraries, and other related state officials. The effect of this effort has been to provide an extensive resource of information about geothermal energy for state policymakers in a form that is useful to them. This non-partisan information has been used as state policymakers attempt to develop their own policy proposals related to geothermal energy in the states. Coordination with the National Geothermal Collaborative: NCSL worked and coordinated with the National Geothermal Collaborative (NGC) to ensure that state legislatures were represented in all aspects of the NGC's efforts. NCSL participated in NGC steering committee conference calls, attended and participated in NGC business meetings and reviewed publications for the NGC. Additionally, NCSL and WSUEP staff drafted a series of eight issue briefs published by the

  8. GEOTHERM user guide

    USGS Publications Warehouse

    Swanson, James R.

    1977-01-01

    GEOTHERM is a computerized geothermal resources file developed by the U.S. Geological Survey. The file contains data on geothermal fields, wells, and chemical analyses from the United states and international sources. The General Information Processing System (GIPSY) in the IBM 370/155 computer is used to store and retrieve data. The GIPSY retrieval program contains simple commands which can be used to search the file, select a narrowly defined subset, sort the records, and output the data in a variety of forms. Eight commands are listed and explained so that the GEOTHERM file can be accessed directly by geologists. No programming experience is necessary to retrieve data from the file.

  9. Geothermal energy program overview

    NASA Astrophysics Data System (ADS)

    1991-12-01

    The mission of the Geothermal Energy Program is to develop the science and technology necessary for tapping our nation's tremendous heat energy sources contained within the Earth. Geothermal energy is a domestic energy source that can produce clean, reliable, cost-effective heat and electricity for our nation's energy needs. Geothermal energy - the heat of the Earth - is one of our nation's most abundant energy resources. In fact, geothermal energy represents nearly 40 percent of the total U.S. energy resource base and already provides an important contribution to our nation's energy needs. Geothermal energy systems can provide clean, reliable, cost-effective energy for our nation's industries, businesses, and homes in the form of heat and electricity. The U.S. Department of Energy's (DOE) Geothermal Energy Program sponsors research aimed at developing the science and technology necessary for utilizing this resource more fully. Geothermal energy originates from the Earth's interior. The hottest fluids and rocks at accessible depths are associated with recent volcanic activity in the western states. In some places, heat comes to the surface as natural hot water or steam, which have been used since prehistoric times for cooking and bathing. Today, wells convey the heat from deep in the Earth to electric generators, factories, farms, and homes. The competitiveness of power generation with lower quality hydrothermal fluids, geopressured brines, hot dry rock, and magma (the four types of geothermal energy), still depends on the technical advancements sought by DOE's Geothermal Energy Program.

  10. Attenuation and source properties at the Coso Geothermal area, California

    USGS Publications Warehouse

    Hough, S.E.; Lees, J.M.; Monastero, F.

    1999-01-01

    We use a multiple-empirical Green's function method to determine source properties of small (M -0.4 to 1.3) earthquakes and P- and S-wave attenuation at the Coso Geothermal Field, California. Source properties of a previously identified set of clustered events from the Coso geothermal region are first analyzed using an empirical Green's function (EGF) method. Stress-drop values of at least 0.5-1 MPa are inferred for all of the events; in many cases, the corner frequency is outside the usable bandwidth, and the stress drop can only be constrained as being higher than 3 MPa. P- and S-wave stress-drop estimates are identical to the resolution limits of the data. These results are indistinguishable from numerous EGF studies of M 2-5 earthquakes, suggesting a similarity in rupture processes that extends to events that are both tiny and induced, providing further support for Byerlee's Law. Whole-path Q estimates for P and S waves are determined using the multiple-empirical Green's function (MEGF) method of Hough (1997), whereby spectra from clusters of colocated events at a given station are inverted for a single attenuation parameter, ??, with source parameters constrained from EGF analysis. The ?? estimates, which we infer to be resolved to within 0.01 sec or better, exhibit almost as much scatter as a function of hypocentral distance as do values from previous single-spectrum studies for which much higher uncertainties in individual ?? estimates are expected. The variability in ?? estimates determined here therefore suggests real lateral variability in Q structure. Although the ray-path coverage is too sparse to yield a complete three-dimensional attenuation tomographic image, we invert the inferred ?? value for three-dimensional structure using a damped least-squares method, and the results do reveal significant lateral variability in Q structure. The inferred attenuation variability corresponds to the heat-flow variations within the geothermal region. A central low

  11. Three-dimensional Q -1 model of the Coso Hot Springs Known Geothermal Resource Area

    NASA Astrophysics Data System (ADS)

    Young, Chi-Yuh; Ward, Ronald W.

    1980-05-01

    Observations of teleseismic P waves above geothermal systems exhibit travel time delays and anomalously high seismic attenuation, which is extremely useful in estimating the thermal regime and the potential of the system. A regional telemetered network of sixteen stations was operated by the U.S. Geological Survey in the Coso Hot Springs Known Geothermal Resources Area (KGRA) for such studies from September 1975 to October 1976. Subsequently, they deployed a portable Centipede array of 26 three-component stations near the center of the anomaly. The seismograms of 44 events recorded by the telemetered array and nine events by the Centipede array were analyzed using the reduced spectral ratio technique to determine the differential attenuation factor δt* for the events recorded with the highest signal-to-noise ratio. The δt* variation observed across the Coso Hot Springs KGRA were small (<0.2 s). A three-dimensional generalized linear inversion of the δt* observations was performed using a three-layer model. A shallow zone of high attenuation exists within the upper 5 km in a region bounded by Coso Hot Springs, Devils Kitchen, and Sugarloaf Mountain probably corresponding to a shallow vapor liquid mixture or `lossy' near surface lithology. No zones of significantly high attenuation occur between 5- and 12- km depth. Between the depth of 12-20 km a thick zone of high attenuation (Q <50) exists, offset toward the east from the surface anomaly.

  12. Principal facts for a gravity survey of the Double Hot Springs Known Geothermal Resource Area, Humboldt County, Nevada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peterson, D.L.; Kaufmann, H.E.

    1978-01-01

    During July 1977, forty-nine gravity stations were obtained in the Double Hot Springs Known Geothermal Resource Area and vicinity, northwestern Nevada. The gravity observations were made with a Worden gravimeter having a scale factor of about 0.5 milligal per division. No terrain corrections have been applied to these data. The earth tide correction was not used in drift reduction. The Geodetic Reference System 1967 formula (International Association of Geodesy, 1967) was used to compute theoretical gravity.

  13. Geothermal system boundary at the northern edge of Patuha Geothermal Field based on integrated study of volcanostratigraphy, geological field mapping, and cool springs contamination by thermal fluids

    NASA Astrophysics Data System (ADS)

    Suryantini; Rachmawati, C.; Abdurrahman, M.

    2017-12-01

    Patuha Geothermal System is a volcanic hydrothermal system. In this type of system, the boundary of the system is often determined by low resistivity (10 ohm.m) anomaly from Magnetotelluric (MT) or DC-Resistivity survey. On the contrary, during geothermal exploration, the system boundary often need to be determined as early as possible even prior of resistivity data available. Thus, a method that use early stage survey data must be developed properly to reduce the uncertainty of the geothermal area extent delineation at the time the geophysical data unavailable. Geological field mapping, volcanostratigraphy analysis and fluid chemistry of thermal water and cold water are the data available at the early stage of exploration. This study integrates this data to delineate the geothermal system boundary. The geological mapping and volcanostratigraphy are constructed to limit the extent of thermal and cold springs. It results that springs in the study area are controlled hydrologically by topography of Patuha Volcanic Crown (complex) or so called PVC, the current geothermal field and Masigit Volcanic Crown (complex) or so called MVC, the dormant volcano not associated with active geothermal system. Some of the cold springs at PVC are contaminated by subsurface steam heated outflow while others are not contaminated. The contaminated cold springs have several characteristics such as higher water temperature than ambient temperature at the time it was measured, higher total disolved solid (TDS), and lower pH. The soluble elements analysis support the early contamination indication by showing higher cation and anion, and positive oxygen shifting of stable isotope of these cool springs. Where as the uncontaminated spring shows similar characteristic with cool springs occur at MVC. The boundary of the system is delineated by an arbitrary line drawn between distal thermal springs from the upflow or contaminated cool springs with the cool uncontaminated springs. This boundary is

  14. Assessment of the geothermal resources of the Socialist Republic of Vietnam

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Flynn, T.; Tien, Phan Cu; Schochert, D.

    1997-12-31

    More than 125 thermal springs, with temperatures greater than 30{degrees}C have been identified and catalogued by the General Department of Geology of Vietnam. Subsurface data are limited and fewer than 10 areas have been identified, on the basis of chemical geothermometers, as capable of supporting electric power production. Six sites in south-central Vietnam have recently been selected for exploration to determine their development potential for electrical power generation. Selected criteria included surface features, chemical geothermometers, proximity to regional faults trends, and regional requirements for electric power. Site visits were conducted to a total of eight areas in south central Vietnammore » where collateral economic developments suggest the need for a local, reliable source of electricity. Physical and visual information on geothermal springs and wells in Vietnam was compared to Nevada`s geothermal resources. Surface geothermal manifestations in Vietnam appear remarkably similar to those in Nevada. Outcrops adjacent to the geothermal areas indicate that Mesozoic-age granites are the most likely basement rocks. Quaternary basalts mapped throughout the study area may be responsible for the thermal anomaly. Initial exploration efforts will focus on three of the six sites, which together may be able to produce 40 to 60 MWe. A cooperative research program with selected Vietnamese governmental agencies includes geologic mapping, surface geophysical and geochemical surveys, and a graduated schedule of drilling programs, ranging in depth from 100 to 1,000 m. Results will be used to define a detailed, deep drilling and testing program at the three prime sites. Development of geothermal power in this region will boost local economic recovery and add stability to the national electric grid.« less

  15. Geomagnetic Survey to Explore High-Temperature Geothermal System in Blawan-Ijen, East Java, Indonesia

    NASA Astrophysics Data System (ADS)

    Daud, Yunus; Rosid, Syamsu; Fahmi, Fikri; Yunus, Faris Maulana; Muflihendri, Reza

    2018-02-01

    Ijen geothermal area is high-temperature geothermal system located in Bondowoso regency, East Java. It is categorized as caldera-hosted geothermal system which is covered by quaternary andesitic volcanic rocks with steep topography at the surrounding. Several surface thermal manifestations are found, such as altered rocks near Mt. Kukusan and a group of Blawan hotsprings in the northern part of the caldera. Geomagnetic survey was conducted at 72 stations which is distributed inside the caldera to delineate the existence of hydrothermal activity. Magnetic anomaly was obtained by reducing total magnetic measured on the field by IGRF and diurnal variation. Reduction to pole (RTP) method was applied with geomagnetic inclination of about -32°. In general, the result shows that high magnetic anomaly is distributed at the boundary of study area, while low magnetic anomaly is observed in the centre. The low anomaly indicates demagnetized rock that probably caused by hydrothermal activity. It has a good correlation with surface alteration observed close to Mt. Kukusan as well as high temperature reservoir drilled in the centre of caldera. Accordingly, the low magnetic anomaly also presents the possibility of geothermal reservoir in Ijen geothermal area.

  16. Geologic map of the Bartlett Springs Fault Zone in the vicinity of Lake Pillsbury and adjacent areas of Mendocino, Lake, and Glenn Counties, California

    USGS Publications Warehouse

    Ohlin, Henry N.; McLaughlin, Robert J.; Moring, Barry C.; Sawyer, Thomas L.

    2010-01-01

    The Lake Pillsbury area lies in the eastern part of the northern California Coast Ranges, along the east side of the transform boundary between the Pacific and North American plates (fig. 1). The Bartlett Springs Fault Zone is a northwest-trending zone of faulting associated with this eastern part of the transform boundary. It is presently active, based on surface creep (Svarc and others, 2008), geomorphic expression, offset of Holocene units (Lienkaemper and Brown, 2009), and microseismicity (Bolt and Oakeshott, 1982; Dehlinger and Bolt, 1984; DePolo and Ohlin, 1984). Faults associated with the Bartlett Springs Fault Zone at Lake Pillsbury are steeply dipping and offset older low to steeply dipping faults separating folded and imbricated Mesozoic terranes of the Franciscan Complex and interleaved rocks of the Coast Range Ophiolite and Great Valley Sequence. Parts of this area were mapped in the late 1970s and 1980s by several investigators who were focused on structural relations in the Franciscan Complex (Lehman, 1978; Jordan, 1975; Layman, 1977; Etter, 1979). In the 1980s the U.S. Geological Survey (USGS) mapped a large part of the area as part of a mineral resource appraisal of two U.S. Forest Service Roadless areas. For evaluating mineral resource potential, the USGS mapping was published at a scale of 1:62,500 as a generalized geologic summary map without a topographic base (Ohlin and others, 1983; Ohlin and Spear, 1984). The previously unpublished mapping with topographic base is presented here at a scale of 1:30,000, compiled with other mapping in the vicinity of Lake Pillsbury. The mapping provides a geologic framework for ongoing investigations to evaluate potential earthquake hazards and structure of the Bartlett Springs Fault Zone. This geologic map includes part of Mendocino National Forest (the Elk Creek Roadless Area) in Mendocino, Glenn, and Lake Counties and is traversed by several U.S. Forest Service Routes, including M1 and M6 (fig. 2). The study

  17. Application effectiveness of the microtremor survey method in the exploration of geothermal resources

    NASA Astrophysics Data System (ADS)

    Tian, Baoqing; Xu, Peifen; Ling, Suqun; Du, Jianguo; Xu, Xueqiu; Pang, Zhonghe

    2017-10-01

    Geophysical techniques are critical tools of geothermal resource surveys. In recent years, the microtremor survey method, which has two branch techniques (the microtremor sounding technique and the two-dimensional (2D) microtremor profiling technique), has become a common method for geothermal resource exploration. The results of microtremor surveys provide important deep information for probing structures of geothermal storing basins and researching the heat-controlling structures, as well as providing the basis for drilling positions of geothermal wells. In this paper, the southern Jiangsu geothermal resources area is taken as a study example. By comparing the results of microtremor surveys and drilling conclusions, and analyzing microtremor survey effectiveness, and geological and technical factors such as observation radius and sampling frequency, we study the applicability of the microtremor survey method and the optimal way of working with this method to achieve better detection results. A comparative study of survey results and geothermal drilling results shows that the microtremor sounding technique effectively distinguishes sub-layers and determines the depth of geothermal reservoirs in the area with excellent layer conditions. The error of depth is generally no more than 8% compared with the results of drilling. It detects deeper by adjusting the size of the probing radius. The 2D microtremor profiling technique probes exactly the buried structures which display as low velocity anomalies in the apparent velocity profile of the S-wave. The anomaly is the critical symbol of the 2D microtremor profiling technique to distinguish and explain the buried geothermal structures. 2D microtremor profiling results provide an important basis for locating exactly the geothermal well and reducing the risk of drilling dry wells.

  18. Geothermal Risk Reduction via Geothermal/Solar Hybrid Power Plants. Final Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wendt, Daniel; Mines, Greg; Turchi, Craig

    There are numerous technical merits associated with a renewable geothermal-solar hybrid plant concept. The performance of air-cooled binary plants is lowest when ambient temperatures are high due to the decrease in air-cooled binary plant performance that occurs when the working fluid condensing temperature, and consequently the turbine exhaust pressure, increases. Electrical power demand is generally at peak levels during periods of elevated ambient temperature and it is therefore especially important to utilities to be able to provide electrical power during these periods. The time periods in which air-cooled binary geothermal power plant performance is lowest generally correspond to periods ofmore » high solar insolation. Use of solar heat to increase air-cooled geothermal power plant performance during these periods can improve the correlation between power plant output and utility load curves. While solar energy is a renewable energy source with long term performance that can be accurately characterized, on shorter time scales of hours or days it can be highly intermittent. Concentrating solar power (CSP), aka solar-thermal, plants often incorporate thermal energy storage to ensure continued operation during cloud events or after sunset. Hybridization with a geothermal power plant can eliminate the need for thermal storage due to the constant availability of geothermal heat. In addition to the elimination of the requirement for solar thermal storage, the ability of a geothermal/solar-thermal hybrid plant to share a common power block can reduce capital costs relative to separate, stand-alone geothermal and solar-thermal power plant installations. The common occurrence of long-term geothermal resource productivity decline provides additional motivation to consider the use of hybrid power plants in geothermal power production. Geothermal resource productivity decline is a source of significant risk in geothermal power generation. Many, if not all, geothermal

  19. Perylene in Lake Biwa sediments originating from Cenococcum geophilum in its catchment area

    NASA Astrophysics Data System (ADS)

    Itoh, Nobuyasu; Sakagami, Nobuo; Torimura, Masaki; Watanabe, Makiko

    2012-10-01

    Perylene, which is composed of five benzene rings, is commonly found in sediments throughout the world at concentrations and distributions that are different from those of other polycyclic aromatic hydrocarbons. The only information available on the origin of perylene comes from 4,9-dihydroxyperylene-3,10-quinone (DHPQ), which originates from fungal component symbiosis or from parasites on plants; however, there is no direct evidence of a mechanism of perylene formation. In this study, we examined the relationship between sedimentary perylene and Cenococcum geophilum (C. geophilum) in a catchment area at Lake Biwa. Sclerotium grains of C. geophilum containing DHPQ were found in this catchment area (approximately 40 balls kg-1 dried soil for >1 mm-ϕ), and small sclerotium grains were frequently found in the sediment. In the sediment sample, we also found broken particles containing perylene, and they had a porous structure characteristic of sclerotium grains. Furthermore, the particles contained DHPQ in different transformation stages to perylene via 3,10-perylenequinone (3,10-PQ). This finding was consistent with results from elemental analysis (oxygen/carbon). Because a remarkable amount of DHPQ originating from C. geophilum also exists in the humic acids of soils and because the inputs of compounds to the lake depend strongly on the rivers, perylene in the Lake Biwa sediment originates mainly from the DHPQ of C. geophilum in its catchment area.

  20. Geothermal energy - Ready for use

    NASA Astrophysics Data System (ADS)

    Miskell, J. T.

    1980-11-01

    The use of geothermal energy in the United States for heating applications is discussed. The three major forms of geothermal energy, hydrothermal, pertrothermal and geopressured, are briefly reviewed, with attention given to the types of energy available from each. Federally supported projects demonstrating the use of geothermal hot water to heat homes in Boise, Idaho, and hot dry rocks in Fenton Hill, New Mexico to produce electricity are presented. Data available from existing geothermal energy applications are presented which show that geothermal is cost competitive with conventional energy sources using existing technology, and government economic incentives to the producers and users of geothermal energy are indicated. Finally, advanced equipment currently under development for the generation of electricity from geothermal resources at reduced costs is presented.

  1. Geothermal Data | Geospatial Data Science | NREL

    Science.gov Websites

    Identified Onshore Geopressured Geothermal Energy in Texas and Louisiana provides additional information on Geothermal Data Geothermal Data These datasets detail the geothermal resource available in the Metadata Geothermal Zip 5.4 MB 03/05/2009 geothermal.xml This dataset is a qualitative assessment of

  2. Cancer incidence among population utilizing geothermal hot water: a census-based cohort study.

    PubMed

    Kristbjornsdottir, Adalbjorg; Rafnsson, Vilhjalmur

    2013-12-15

    The aim of the study was to assess whether utilization of geothermal hot-water is associated with risk of cancer. The cohort from census was followed from 1981 to 2010 in nation-wide death and cancer registries. The moving apart of American-Eurasian tectonic plates, observed in Iceland, results in high volcanic activity. The definition of the study populations was based on geological information. The target population was inhabitants of communities located on bedrock younger than 3.3 million years, utilizing hot-water supply generated from geothermal wells since 1972. The two reference populations were inhabitants of communities without this hot-water supply located on areas with less volcanic/geothermal activity, and bedrock older than 3.3 million years. Hazard ratio (HR), and 95% confidence intervals (CI) were adjusted for age, gender, education, housing, reproductive factors and smoking. HR in the geothermal hot-water supply areas for all cancer was 1.15 (95% CI 1.05-1.25) as compared with nongeothermal areas. The HR for breast cancer was 1.40 (1.12-1.75), prostate cancer 1.61 (1.29-2.00), kidney cancer 1.64 (1.11-2.41), lymphatic and haematopoietic tissue cancers 1.45 (1.08-1.95), and for basal cell carcinoma (BCC) of the skin 1.46 (1.16-1.82). Positive exposure-response relations were observed between the risk of these cancers and the degree of volcanic/geothermal activity in the reference areas. Increased incidence of all cancers, breast, prostate, kidney cancer and BCC of the skin was found among the population utilizing geothermal hot-water for decades. More precise information on exposure is needed in future studies. Copyright © 2013 UICC.

  3. Lake Powell

    NASA Image and Video Library

    2007-09-20

    The white ring around Lake Powell tells the story. The surface is down 98 feet. This is critical, because Powell, Lake Mead, and other lakes along the Colorado River provide water for millions of people in five states. We are in the eighth year of a drought on the Colorado River. This year was the driest year ever reported in Southern California, and there is a severe drought in Northern California, down to less than 30-percent of snow pack. This ASTER image of part of Lake Powell was acquired in 2001. The gray area depicts the shrunken, reduced 2007 lake extent compared to the extended, larger black area in 2001. The image covers an area of 24 x 30 km, and is centered near 37.1 degrees north latitude, 111.3 degrees west longitude. This image from NASA Terra satellite. http://photojournal.jpl.nasa.gov/catalog/PIA10614

  4. Mapping ecosystem service indicators in a Great Lakes estuarine Area of Concern

    EPA Science Inventory

    Estuaries provide multiple ecosystem services from which humans benefit. Currently, thirty-six Great Lakes estuaries in the United States and Canada are designated as Areas of Concern (AOCs) due to a legacy of chemical contamination, degraded habitat, and non-point-source polluti...

  5. Heat‐tolerant Flowering Plants of Active Geothermal Areas in Yellowstone National Park

    PubMed Central

    STOUT, RICHARD G.; AL‐NIEMI, THAMIR S.

    2002-01-01

    A broad survey of most of the major geyser basins within Yellowstone National Park (Wyoming, USA) was conducted to identify the flowering plants which tolerate high rhizosphere temperatures (≥40 °C) in geothermally heated environments. Under such conditions, five species of monocots and four species of dicots were repeatedly found. The predominant flowering plants in hot soils (>40 °C at 2–5 cm depth) were grasses, primarily Dichanthelium lanuginosum. Long‐term (weeks to months) rhizosphere temperatures of individual D. lanuginosum above 40 °C were recorded at several different locations, both in the summer and winter. The potential role of heat shock proteins (HSPs) in the apparent adaptation of these plants to chronically high rhizosphere temperatures was examined. Antibodies to cytoplasmic class I small heat shock proteins (sHSPs) and to HSP101 were used in Western immunoblot analyses of protein extracts from plants collected from geothermally heated soils. Relatively high levels of proteins reacting with anti‐sHSP antibodies were consistently detected in root extracts from plants experiencing rhizosphere temperatures above 40 °C, though these proteins were usually not highly expressed in leaf extracts from the same plants. Proteins reacting with antibodies to HSP101 were also present both in leaf and root extracts from plants collected from geothermal soils, but their levels of expression were not as closely related to the degree of heat exposure as those of sHSPs. PMID:12197524

  6. Geothermal exploration in Indonesia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Radja, V.T.

    1984-03-01

    Indonesia is blessed with geothermal resources. This fortunate aspect is directly related to the fact that the archipelago is an island arc created by a subduction zone. Evidence of geothermal activity is common throughout the Islands. Among the islands' many active volcanos are numerous geothermal phenomena. Almost half of the volcanic centers in Indonesia (88 out of 177 centers) contain fumarole and sulfatare features. A brief history of the exploration for geothermal energy in Indonesia is presented.

  7. Time-lapse Joint Inversion of Geophysical Data and its Applications to Geothermal Prospecting - GEODE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Revil, Andre

    2015-12-31

    The objectives of this project were to develop new algorithms to decrease the cost of drilling for geothermal targets during the exploration phase of a hydrothermal field and to improve the monitoring of a geothermal field to better understand its plumbing system and keep the resource renewable. We developed both new software and algorithms for geothermal explorations (that can also be used in other areas of interest to the DOE) and we applied the methods to a geothermal field of interest to ORMAT in Nevada.

  8. The origin of the geothermal anomaly identified in the Barcelona underground (Spain): Future perspectives of this urban geothermal resource

    NASA Astrophysics Data System (ADS)

    Ángel Marazuela, Miguel; Vázquez-Suñé, Enric; Criollo-Manjarrez, Rotman; García-Gil, Alejandro

    2017-04-01

    During the drilling of line 9 of the Barcelona underground (Spain), a geothermal anomaly was detected, in which groundwater temperature was found to be up to 50°C. Previously, during the construction of the Fondo station in Santa Coloma de Gramanet (SCG), temperatures up to 37°C were already detected in this area. To study the feasibility of a future energy exploitation of the geothermal anomaly, a local and regional study is being undertaken. We present the first results of the new study. The objectives of this study were (1) to understand the flux regime of the hydrothermal system on both, local and large scale, (2) to explain the origin of the identified geothermal anomaly in SCG, and (3) to know the quality of the geothermal potential of the underground resources. To achieve these goals, different numerical models of groundwater flow and heat transport were performed. The area of study is constituted mainly of low permeability Palaeozoic granodiorites strongly weathered towards the top (lehm). These materials are affected by two sets of faults: the first one consists of porphyrýs dikes with a SW-NE direction and the second fault family which presents a NW-SE direction (Vázquez-Suñé et al., 2016). In the southeast area, the Quaternary deposits of the Besós River delta overlap these Palaeozoic materials. In spite of being a regional model, all these geological features have been incorporated in a complex mesh with more than 2.5 million finite elements. The results obtained suggest that in the case of SCG, the thermal anomaly found on the surface would have its origin in the rapid ascent of the hot water through these fracturing planes. Understanding the hydrogeothermal operation of the SCG system in detail and its possible temporal evolution will be of great interest for future evaluation, monitoring and management of the geothermal resources found, as well as to understand the interaction of these systems with urban infrastructures. REFERENCES V

  9. A multidisciplinary approach for the characterisation of fault zones in geothermal areas in central Mexico

    NASA Astrophysics Data System (ADS)

    Comina, Cesare; Ferrero, Anna Maria; Mandrone, Giuseppe; Vinciguerra, Sergio

    2017-04-01

    There are more than 500 geothermal areas in the Trans-Mexican Volcanic Belt of central Mexico. Of these, two are presently object of a transnational project between EU and Mexico (GEMex): Acoculco, where there is already a commercial exploitation, and Los Humeros, at present not developed yet. The GEMex project aims to improve the resource assessment and the reservoir characterization using novel geophysical and geological methods and interpretations. One of the main issues controlling the geothermal system is the presence of pervasive fracture systems affecting the carbonatic basements underlying the volcanic complex (basalts and andesites). We propose the characterization of rock masses (rock and fractures) using a multiscale analysis, from the field to the outcrop up to the micro scale integrating a number of techniques. In detail, the University of Torino unit will take care of: 1) Technical field studies aimed to the characterization of the mechanical transitions throughout brittle deformation zones, from the intact rock, to the damage zone to the shear/slip zone; moreover, key geophysical parameters (seismic and electrical properties) will be measured; 2) Petrophysical and minero-petrographic detailed studies on representative samples will be performed at room temperature; verification of the mechanical properties of the samples subjected to cycles of heating up to the temperatures of the reservoir (> 400 °C) will be done; measurements of the geophysical properties of the samples will be done in comparison with the measures in place. 3) Numerical modeling to estimate the petrophysical, geophysical and geomechanical properties of the rock mass under the P and T conditions of the reservoir (i.e., using Comsol, VGeST, UDEC, 3DEC, ...). Detailed geological field studies and photogrammetry/laser scanner imaging of studied outcrops are supposed to be available soon: multiscale analysis will benefis from these new data. Results will be shared between EU and Mexican

  10. Geothermal Resource Reporting Metric (GRRM) Developed for the U.S. Department of Energy's Geothermal Technologies Office

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Young, Katherine R.; Wall, Anna M.; Dobson, Patrick F.

    This paper reviews a methodology being developed for reporting geothermal resources and project progress. The goal is to provide the U.S. Department of Energy's (DOE) Geothermal Technologies Office (GTO) with a consistent and comprehensible means of evaluating the impacts of its funding programs. This framework will allow the GTO to assess the effectiveness of research, development, and deployment (RD&D) funding, prioritize funding requests, and demonstrate the value of RD&D programs to the U.S. Congress and the public. Standards and reporting codes used in other countries and energy sectors provide guidance to develop the relevant geothermal methodology, but industry feedback andmore » our analysis suggest that the existing models have drawbacks that should be addressed. In order to formulate a comprehensive metric for use by the GTO, we analyzed existing resource assessments and reporting methodologies for the geothermal, mining, and oil and gas industries, and sought input from industry, investors, academia, national labs, and other government agencies. Using this background research as a guide, we describe a methodology for evaluating and reporting on GTO funding according to resource grade (geological, technical and socio-economic) and project progress. This methodology would allow GTO to target funding, measure impact by monitoring the progression of projects, or assess geological potential of targeted areas for development.« less

  11. Integrated Riparian Area Management on the Tule Lake Allotment, Lassen County

    Treesearch

    Bill Flournoy; Don Lancaster; Paul Roush

    1989-01-01

    The Bureau of Land Management, Alturas Resource Area with the cooperation of the Tule Lake Allotment permittees and private landowners has embarked on a riparian enhancement program for the allotment which crosses many traditional boundaries and barriers in land management and land management planning. Currently in the plan development stages the concept provides for a...

  12. Thin, Conductive Permafrost Surrounding Lake Fryxell Indicates Salts From Past Lakes, McMurdo Dry Valleys, Antarctica

    NASA Astrophysics Data System (ADS)

    Foley, N.; Tulaczyk, S. M.; Gooseff, M. N.; Myers, K. F.; Doran, P. T.; Auken, E.; Dugan, H. A.; Mikucki, J.; Virginia, R. A.

    2017-12-01

    In the McMurdo Dry Valleys (MDV), permafrost should be thick and liquid water rare. However, despite the well below zero mean annual temperature in this cryospheric desert, liquid water can be found in lakes, summer melt streams, subglacial outflow, and - recent work has shown - underneath anomalously thin permafrost. In part, this niche hydrosphere is maintained by the presence of salts, which depress the freezing point of water to perhaps as cold as -10° Celsius. We detected widespread salty water across the MDV in lakes and at depth using a helicopter-borne Time Domain Electromagnetic (TDEM) sensor. By using the presence of brines to mark the transition from frozen permafrost (near the surface) to unfrozen ground (at depth), we have created a map of permafrost thickness in Lower Taylor Valley (LTV), a large MDV with a complex history of glaciation and occupation by lakes. Our results show that permafrost is thinner ( 200m) than would be expected based on geothermal gradient measurements (up to 1000m), a result of the freezing point depression caused by salt and potentially enhanced by an unfinished transient freezing process. Near Lake Fryxell, a large, brackish lake in the center of LTV, permafrost is very thin (about 30-40m) and notably more electrically conductive than more distal permafrost. This thin ring of conductive permafrost surrounding the lake basin most likely reflects the high presence of salts in the subsurface, preventing complete freezing. These salts may be a remnant of the salty bottom waters of a historic larger lake (LGM glacially dammed Lake Washburn) or the remnant of salty basal water from a past advance of Taylor Glacier, which now sits many km up-valley but is known to contain brines which currently flow onto the surface and directly into the subsurface aquifer.

  13. Effects of lake trout refuges on lake whitefish and cisco in the Apostle Islands Region of Lake Superior

    USGS Publications Warehouse

    Zuccarino-Crowe , Chiara M.; Taylor, William W.; Hansen, Michael J.; Seider, Michael J.; Krueger, Charles C.

    2016-01-01

    Lake trout refuges in the Apostle Islands region of Lake Superior are analogous to the concept of marine protected areas. These refuges, established specifically for lake trout (Salvelinus namaycush) and closed to most forms of recreational and commercial fishing, were implicated as one of several management actions leading to successful rehabilitation of Lake Superior lake trout. To investigate the potential significance of Gull Island Shoal and Devils Island Shoal refuges for populations of not only lake trout but also other fish species, relative abundances of lake trout, lake whitefish (Coregonus clupeaformis), and cisco (Coregonus artedi) were compared between areas sampled inside versus outside of refuge boundaries. During 1982–2010, lake trout relative abundance was higher and increased faster inside the refuges, where lake trout fishing was prohibited, than outside the refuges. Over the same period, lake whitefish relative abundance increased faster inside than outside the refuges. Both evaluations provided clear evidence that refuges protected these species. In contrast, trends in relative abundance of cisco, a prey item of lake trout, did not differ significantly between areas inside and outside the refuges. This result did not suggest indirect or cascading refuge effects due to changes in predator levels. Overall, this study highlights the potential of species-specific refuges to benefit other fish species beyond those that were the refuges' original target. Improved understanding of refuge effects on multiple species of Great Lakes fishes can be valuable for developing rationales for refuge establishment and predicting associated fish community-level effects.

  14. White Lake AOC

    EPA Pesticide Factsheets

    White Lake is in Muskegon County along the eastern shore of Lake Michigan. It was named an Area of Concern on the Great Lakes under the Great Lakes Water Quality Agreement of 1987 and delisted in 2014.

  15. Play-fairway analysis for geothermal resources and exploration risk in the Modoc Plateau region

    USGS Publications Warehouse

    Siler, Drew; Zhang, Yingqi; Spycher, Nicolas F.; Dobson, Patrick; McClain, James S.; Gasperikova, Erika; Zierenberg, Robert A.; Schiffman, Peter; Ferguson, Colin; Fowler, Andrew; Cantwell, Carolyn

    2017-01-01

    The region surrounding the Modoc Plateau, encompassing parts of northeastern California, southern Oregon, and northwestern Nevada, lies at an intersection between two tectonic provinces; the Basin and Range province and the Cascade volcanic arc. Both of these provinces have substantial geothermal resource base and resource potential. Geothermal systems with evidence of magmatic heat, associated with Cascade arc magmatism, typify the western side of the region. Systems on the eastern side of the region appear to be fault controlled with heat derived from high crustal heat flow, both of which are typical of the Basin and Range. As it has the potential to host Cascade arc-type geothermal resources, Basin and Range-type geothermal resources, and/or resources with characteristics of both provinces, and because there is relatively little current development, the Modoc Plateau region represents an intriguing potential for undiscovered geothermal resources. It remains unclear however, what specific set(s) of characteristics are diagnostic of Modoc-type geothermal systems and how or if those characteristics are distinct from Basin and Range-type or Cascade arc-type geothermal systems. In order to evaluate the potential for undiscovered geothermal resources in the Modoc area, we integrate a wide variety of existing data in order to evaluate geothermal resource potential and exploration risk utilizing ‘play-fairway’ analysis. We consider that the requisite parameters for hydrothermal circulation are: 1) heat that is sufficient to drive circulation, and 2) permeability that is sufficient to allow for fluid circulation in the subsurface. We synthesize data that indicate the extent and distribution of these parameters throughout the Modoc region. ‘Fuzzy logic’ is used to incorporate expert opinion into the utility of each dataset as an indicator of either heat or permeability, and thus geothermal favorability. The results identify several geothermal prospects, areas that

  16. Mapping of the total magnetic field in the area of Lake Balaton

    NASA Astrophysics Data System (ADS)

    Visnovitz, Ferenc; Hegyi, Betti; Raveloson, Andrea; Rozman, Gábor; Lenkey, László; Kovács, Péter; Csontos, András; Heilig, Balázs; Horváth, Ferenc

    2017-04-01

    The Lake Balaton with 600 km2 area represents the largest lake in Central Europe and a blank spot on the magnetic anomaly map of Hungary. It is because the construction of the Hungarian magnetic anomaly map dates back to the 1960s and relied mainly on classical vertical-field balance surveys. To fill the gap, we initiated a systematic mapping using modern magnetometers and positioning system in the framework of a complex geophysical study of Lake Balaton (National Research Project 109255 K). The main goal of this study has been to identify subvolcanic bodies and tectonic structures below the lake and correlate them with well-known features mapped onshore in the vicinity of Balaton. During the magnetic survey an Overhauser field magnetometer (GEM System, GSM-19) was mounted on a plastic boat and towed behind a motorboat in a distance of 20 m with a speed of 6 to 16 km/h depending on weather conditions. Tests measurements showed that at this distance the magnetic noise generated by the motorboat was negligible. We measured total field values with a sampling interval of 1 to 2 s. As a result, the whole lake has been covered by magnetic profiles in an orthogonal grid with spacing of 1 km. During data interpretation we applied for correction of temporal variation of magnetic field registered in the Tihany Geophysical Observatory and normal field correction from a regional model. The final anomaly map in the western part of the lake shows anomalies with amplitudes of 20 to 60 nT and a half wavelength of 0.5 to 1 km. A larger feature was recognized related to the Badacsony Hill a major basaltic bute at the northern shore of the lake. In the middle part of the lake the total field is rather smooth, no significant anomaly has been revealed. However, slight disturbances can be noticed in the proximity of a neotectonic fault zone mapped by high resolution seismic data. In the eastern part of the lake few low amplitude (5-20 nT) anomalies have been observed that are associated

  17. GeothermalLCOE_NoExclusionsforAtlas

    Science.gov Websites

    a qualitative assessment of geothermal potential (Enhanced Geothermal System EGS) for the US based from 3 to 10 km provided by Southern Methodist University Geothermal Laboratory (Blackwell & ;http://www.nrel.gov/gis/cfm/data/GIS_Data_Technology_Specific/United_States/Geothermal

  18. New geothermal site identification and qualification. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    2004-04-01

    This study identifies remaining undeveloped geothermal resources in California and western Nevada, and it estimates the development costs of each. It has relied on public-domain information and such additional data as geothermal developers have chosen to make available. Reserve estimation has been performed by volumetric analysis with a probabilistic approach to uncertain input parameters. Incremental geothermal reserves in the California/Nevada study area have a minimum value of 2,800 grosss MW and a most-likely value of 4,300 gross MW. For the state of California alone, these values are 2,000 and 3,000 gross MW, respectively. These estimates may be conservative to themore » extent that they do not take into account resources about which little or no public-domain information is available. The average capital cost of incremental generation capacity is estimated to average $3,100/kW for the California/Nevada study area, and $2,950/kW for the state of California alone. These cost estimates include exploration, confirmation drilling, development drilling, plant construction, and transmission-line costs. For the purposes of this study, a capital cost of $2,400/kW is considered competitive with other renewable resources. The amount of incremental geothermal capacity available at or below $2,400/kW is about 1,700 gross MW for the California/Nevada study area, and the same amount (within 50-MW rounding) for the state of California alone. The capital cost estimates are only approximate, because each developer would bring its own experience, bias, and opportunities to the development process. Nonetheless, the overall costs per project estimated in this study are believed to be reasonable.« less

  19. Comparison of hyperspectral transformation accuracies of multispectral Landsat TM, ETM+, OLI and EO-1 ALI images for detecting minerals in a geothermal prospect area

    NASA Astrophysics Data System (ADS)

    Hoang, Nguyen Tien; Koike, Katsuaki

    2018-03-01

    Hyperspectral remote sensing generally provides more detailed spectral information and greater accuracy than multispectral remote sensing for identification of surface materials. However, there have been no hyperspectral imagers that cover the entire Earth surface. This lack points to a need for producing pseudo-hyperspectral imagery by hyperspectral transformation from multispectral images. We have recently developed such a method, a Pseudo-Hyperspectral Image Transformation Algorithm (PHITA), which transforms Landsat 7 ETM+ images into pseudo-EO-1 Hyperion images using multiple linear regression models of ETM+ and Hyperion band reflectance data. This study extends the PHITA to transform TM, OLI, and EO-1 ALI sensor images into pseudo-Hyperion images. By choosing a part of the Fish Lake Valley geothermal prospect area in the western United States for study, the pseudo-Hyperion images produced from the TM, ETM+, OLI, and ALI images by PHITA were confirmed to be applicable to mineral mapping. Using a reference map as the truth, three main minerals (muscovite and chlorite mixture, opal, and calcite) were identified with high overall accuracies from the pseudo-images (> 95% and > 42% for excluding and including unclassified pixels, respectively). The highest accuracy was obtained from the ALI image, followed by ETM+, TM, and OLI images in descending order. The TM, OLI, and ALI images can be alternatives to ETM+ imagery for the hyperspectral transformation that aids the production of pseudo-Hyperion images for areas without high-quality ETM+ images because of scan line corrector failure, and for long-term global monitoring of land surfaces.

  20. Lake Powell

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The white ring around Lake Powell tells the story. The surface is down 98 feet. This is critical, because Powell, Lake Mead, and other lakes along the Colorado River provide water for millions of people in five states. We are in the eighth year of a drought on the Colorado River. This year was the driest year ever reported in Southern California, and there is a severe drought in Northern California, down to less than 30-percent of snow pack. This ASTER image of part of Lake Powell was acquired in 2001. The gray area depicts the shrunken, reduced 2007 lake extent compared to the extended, larger black area in 2001.

    The image covers an area of 24 x 30 km, and is centered near 37.1 degrees north latitude, 111.3 degrees west longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.