Simulation of Water-rock Interaction in the Yellowstone Geothermal System Using TOUGHREACT.

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ISBN 13 :
Total Pages : 13 pages
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Book Synopsis Simulation of Water-rock Interaction in the Yellowstone Geothermal System Using TOUGHREACT. by :

Download or read book Simulation of Water-rock Interaction in the Yellowstone Geothermal System Using TOUGHREACT. written by and published by . This book was released on 2003 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Yellowstone geothermal system provides an ideal opportunity to test the ability of reactive transport models to simulate the chemical and hydrological effects of water-rock interaction. Previous studies of the Yellowstone geothermal system have characterized water-rock interaction through analysis of rocks and fluids obtained from both surface and downhole samples. Fluid chemistry, rock mineralogy, permeability, porosity, and thermal data obtained from the Y-8 borehole in Upper Geyser Basin were used to constrain a series of reactive transport simulations of the Yellowstone geothermal system using TOUGHREACT. Three distinct stratigraphic units were encountered in the 153.4 m deep Y-8 drill core: volcaniclastic sandstone, perlitic rhyolitic lava, and nonwelded pumiceous tuff. The main alteration phases identified in the Y-8 core samples include clay minerals, zeolites, silica polymorphs, adularia, and calcite. Temperatures observed in the Y-8 borehole increase with depth from sub-boiling conditions at the surface to a maximum of 169.8 C at a depth of 104.1 m, with near-isothermal conditions persisting down to the well bottom. 1-D models of the Y-8 core hole were constructed to simulate the observed alteration mineral assemblage given the initial rock mineralogy and observed fluid chemistry and temperatures. Preliminary simulations involving the perlitic rhyolitic lava unit are consistent with the observed alteration of rhyolitic glass to form celadonite.

Simulation of Water-rock Interaction in the Yellowstone Geothermal System Using TOUGHREACT.

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ISBN 13 :
Total Pages : 6 pages
Book Rating : 4.:/5 (316 download)

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Book Synopsis Simulation of Water-rock Interaction in the Yellowstone Geothermal System Using TOUGHREACT. by : P. F. Dobson

Download or read book Simulation of Water-rock Interaction in the Yellowstone Geothermal System Using TOUGHREACT. written by P. F. Dobson and published by . This book was released on 2003 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Yellowstone geothermal system provides an ideal opportunity to test the ability of reactive transport models to accurately simulate water-rock interaction. Previous studies of the Yellowstone geothermal system have characterized water-rock interaction through analysis of rocks and fluids obtained from both surface and downhole samples. Fluid chemistry, rock mineralogy, permeability, porosity, and thermal data obtained from the Y-8 borehole in Upper Geyser Basin were used to constrain a series of reactive transport simulations of the Yellowstone geothermal system using TOUGHREACT. Three distinct stratigraphic units were encountered in the 153.4 m deep Y-8 drill core: volcaniclastic sandstone, perlitic rhyolitic lava, and nonwelded pumiceous tuff. The main alteration phases identified in the Y-8 core samples include clay minerals, zeolites, silica polymorphs, adularia, and calcite. Temperatures observed in the Y-8 borehole increase with depth from sub-boiling conditions at the surface to a maximum of 169.8 C at a depth of 104.1 m, with near-isothermal conditions persisting down to the well bottom. 1-D models of the Y-8 core hole were constructed to determine if TOUGHREACT could accurately predict the observed alteration mineral assemblage given the initial rock mineralogy and observed fluid chemistry and temperatures. Preliminary simulations involving the perlitic rhyolitic lava unit are consistent with the observed alteration of rhyolitic glass to form celadonite.

Hydrothermal Processes Above the Yellowstone Magma Chamber

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Publisher : Geological Society of America
ISBN 13 : 0813724597
Total Pages : 104 pages
Book Rating : 4.8/5 (137 download)

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Book Synopsis Hydrothermal Processes Above the Yellowstone Magma Chamber by : Lisa A. Morgan

Download or read book Hydrothermal Processes Above the Yellowstone Magma Chamber written by Lisa A. Morgan and published by Geological Society of America. This book was released on 2009-01-01 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Home to more than 10,000 thermal features, Yellowstone has experienced over 20 large hydrothermal explosions producing craters from 100 to over 2500 meters in diameter during the past 16,000 years. Using new mapping, sampling, and analysis techniques, this volume documents a broad spectrum of ages and geologic settings for these events and considers additional processes and alternative triggering mechanisms that have not been explored in previous studies. Although large hydrothermal explosions are rare on the human time scale, the potential for future explosions in Yellowstone is not insignificant, and events large enough to create a 100-m-wide crater might be expected every 200 years. This work presents information useful for determining the timing, distribution, and possible causes of these events in Yellowstone, which will aid in the planning of monitoring strategies and the anticipation of hydrothermal explosions."--Publisher's description.

Treatise on Geochemistry

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Publisher : Newnes
ISBN 13 : 0080983006
Total Pages : 14787 pages
Book Rating : 4.0/5 (89 download)

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Book Synopsis Treatise on Geochemistry by :

Download or read book Treatise on Geochemistry written by and published by Newnes. This book was released on 2013-10-19 with total page 14787 pages. Available in PDF, EPUB and Kindle. Book excerpt: This extensively updated new edition of the widely acclaimed Treatise on Geochemistry has increased its coverage beyond the wide range of geochemical subject areas in the first edition, with five new volumes which include: the history of the atmosphere, geochemistry of mineral deposits, archaeology and anthropology, organic geochemistry and analytical geochemistry. In addition, the original Volume 1 on "Meteorites, Comets, and Planets" was expanded into two separate volumes dealing with meteorites and planets, respectively. These additions increased the number of volumes in the Treatise from 9 to 15 with the index/appendices volume remaining as the last volume (Volume 16). Each of the original volumes was scrutinized by the appropriate volume editors, with respect to necessary revisions as well as additions and deletions. As a result, 27% were republished without major changes, 66% were revised and 126 new chapters were added. In a many-faceted field such as Geochemistry, explaining and understanding how one sub-field relates to another is key. Instructors will find the complete overviews with extensive cross-referencing useful additions to their course packs and students will benefit from the contextual organization of the subject matter Six new volumes added and 66% updated from 1st edition. The Editors of this work have taken every measure to include the many suggestions received from readers and ensure comprehensiveness of coverage and added value in this 2nd edition The esteemed Board of Volume Editors and Editors-in-Chief worked cohesively to ensure a uniform and consistent approach to the content, which is an amazing accomplishment for a 15-volume work (16 volumes including index volume)!

Geothermal Power Generation

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Publisher : Elsevier
ISBN 13 : 044324751X
Total Pages : 977 pages
Book Rating : 4.4/5 (432 download)

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Book Synopsis Geothermal Power Generation by : Ronald DiPippo

Download or read book Geothermal Power Generation written by Ronald DiPippo and published by Elsevier. This book was released on 2024-10-11 with total page 977 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geothermal Power Generation, New Developments and Innovations, Second Edition provides an update to the advanced energy technologies that are urgently required to meet the challenges of economic development, climate change mitigation, and energy security. Edited by respected and leading experts in the field, this book provides a comprehensive overview of the major aspects of geothermal power production. Chapters cover resource discovery, resource characterization, energy conversion systems, design, economic considerations, and a range of fascinating and updated case studies from across the world.Geothermal resources are considered renewable and are currently the only renewable source able to generate baseload electricity while producing very low levels of greenhouse gas emissions, thus playing a key role in future energy needs. - Provides readers with a comprehensive and systematic overview of geothermal power generation - Presents an update to advanced energy technologies that are urgently required to meet the challenges of economic development, climate change mitigation, and energy security - Edited by authorities in the field and contributed to by global experts in their areas - Supports sustainability and the United Nations Sustainable Development Goals (UN SDGs) 7, 9, 11 and 13

Hydrothermal Processes Above the Yellowstone Magma Chamber

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Publisher :
ISBN 13 : 9780813724591
Total Pages : 108 pages
Book Rating : 4.7/5 (245 download)

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Book Synopsis Hydrothermal Processes Above the Yellowstone Magma Chamber by : Lisa A. Morgan

Download or read book Hydrothermal Processes Above the Yellowstone Magma Chamber written by Lisa A. Morgan and published by . This book was released on 2009 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrothermal explosions are violent and dramatic events resulting in the rapid ejection of boiling water, steam, mud, and rock fragments from source craters that range from a few meters up to more than 2 km in diameter; associated breccia can be emplaced as much as 3 to 4 km from the largest craters. Hydrothermal explosions occur where shallow interconnected reservoirs of steam- and liquid-saturated fluids with temperatures at or near the boiling curve underlie thermal fields. Sudden reduction in confining pressure causes fluids to flash to steam, resulting in significant expansion, rock fragmentation, and debris ejection. In Yellowstone, hydrothermal explosions are a potentially significant hazard for visitors and facilities and can damage or even destroy thermal features. The breccia deposits and associated craters formed from hydrothermal explosions are mapped as mostly Holocene (the Mary Bay deposit is older) units throughout Yellowstone National Park (YNP) and are spatially related to within the 0.64-Ma Yellowstone caldera and along the active Norris-Mammoth tectonic corridor.

Use of TOUGHREACT to Simulate Effects of Fluid Chemistry OnInjectivity in Fractured Geothermal Reservoirs with High Ionic StrengthFluids

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ISBN 13 :
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Book Synopsis Use of TOUGHREACT to Simulate Effects of Fluid Chemistry OnInjectivity in Fractured Geothermal Reservoirs with High Ionic StrengthFluids by :

Download or read book Use of TOUGHREACT to Simulate Effects of Fluid Chemistry OnInjectivity in Fractured Geothermal Reservoirs with High Ionic StrengthFluids written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent studies suggest that mineral dissolution/precipitation and clay swelling effects could have a major impact on the performance of hot dry rock (HDR) and hot fractured rock (HFR) reservoirs. A major concern is achieving and maintaining adequate injectivity, while avoiding the development of preferential short-circuiting flow paths. A Pitzer ionic interaction model has been introduced into the publicly available TOUGHREACT code for solving non-isothermal multi-phase reactive geochemical transport problems under conditions of high ionic strength, expected in typical HDR and HFR systems. To explore chemically-induced effects of fluid circulation in these systems, we examine ways in which the chemical composition of reinjected waters can be modified to improve reservoir performance. We performed a number of coupled thermo-hydrologic-chemical simulations in which the fractured medium was represented by a one-dimensional MINC model (multiple interacting continua). Results obtained with the Pitzer activity coefficient model were compared with those using an extended Debye-Hueckel equation. Our simulations show that non-ideal activity effects can be significant even at modest ionic strength, and can have major impacts on permeability evolution in injection-production systems. Alteration of injection water chemistry, for example by dilution with fresh water, can greatly alter precipitation and dissolution effects, and can offer a powerful tool for operating hot dry rock and hot fractured rock reservoirs in a sustainable manner.

Hydrothermal Water-rock Reaction Modeling with Microbial Considerations: Rabbit Creek Area, Yellowstone National Park, WY

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Publisher :
ISBN 13 :
Total Pages : 158 pages
Book Rating : 4.:/5 (17 download)

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Book Synopsis Hydrothermal Water-rock Reaction Modeling with Microbial Considerations: Rabbit Creek Area, Yellowstone National Park, WY by : Shanna Law

Download or read book Hydrothermal Water-rock Reaction Modeling with Microbial Considerations: Rabbit Creek Area, Yellowstone National Park, WY written by Shanna Law and published by . This book was released on 2018 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water-rock reactions at depth are the main control on aqueous hydrothermal chemistries of hot springs and other thermal features. Thermophilic microbes living in the hydrothermal system are a secondary control on aqueous hydrothermal chemistries and are expected to have increasing influence as spring temperatures decrease. The Rabbit Creek area of Yellowstone National Park (YNP) is an ideal case study for investigating the geologic and biologic controls on aqueous hydrothermal chemistries due to the proximity of the drill core Y-5 to geochemically diverse hydrothermal features (17.3°C to 92.2°C ± 0.1°C; field pH values 6.50 to 9.60 ± 0.05). The modeling program EQ3/6 was used to compare expected and predicted hydrothermal aqueous chemical speciations of hydrothermal features in the Rabbit Creek area. The expected aqueous chemical speciations were found using EQ3 to speciate initial measured concentrations of dissolved major ions and trace elements from each thermal feature. EQ3/6 was used to predict local water-rock reactions by interacting local meteoric water with the summarized mineralogy of the altered rhyolitic tuff of drill core Y-5. The EQ3/6 model was cooled, depressurized, and calibrated to the aqueous chemistry of a proximal, near boiling spring expected to have negligible microbial activity (based on low extracted DNA yields of ~5 ng DNA/g of sediment). The calibrated EQ3/6 water-rock reaction model was further cooled to the measured temperature of each hydrothermal feature analyzed to predict changes in aqueous chemical speciation. Speciated chemistries of springs were generally similar to predictions from modeled water-rock interactions, but differences increased as temperatures cooled. The EQ3/6 predictions for most springs showed deficiencies in silica, aluminum, and sulfur compared to EQ3 speciations, which could be improved by adding H2S (g) to the system and allowing for supersaturation in the models. Variations in calcium in the thermal features were expected to be a function of plagioclase remaining unsaturated and being more variable in the Y-5 subsurface than the other minerals. Discrepancies in pH between field measurements, EQ3 speciated pH, and EQ3/6 predicted pH values for each feature represent disequilibrium. Part of the disequilibrium in cooler features (

Using Toughreact to Model Reactive Fluid Flow and Geochemical Transport in Hydrothermal Systems

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ISBN 13 :
Total Pages : 12 pages
Book Rating : 4.:/5 (684 download)

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Book Synopsis Using Toughreact to Model Reactive Fluid Flow and Geochemical Transport in Hydrothermal Systems by :

Download or read book Using Toughreact to Model Reactive Fluid Flow and Geochemical Transport in Hydrothermal Systems written by and published by . This book was released on 2003 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The interaction between hydrothermal fluids and the rocks through which they migrate alters the earlier formed primary minerals and leads to the formation of secondary minerals, resulting in changes in the physical and chemical properties of the system. We have developed a comprehensive numerical simulator, TOUGHREACT, which considers nonisothermal multi-component chemical transport in both liquid and gas phases. A variety of subsurface thermo-physical-chemical processes is considered under a wide range of conditions of pressure, temperature, water saturation, and ionic strength. The code can be applied to problems in fundamental analysis of the hydrothermal systems and in the exploration of geothermal reservoirs including chemical evolution, mineral alteration, mineral scaling, changes of porosity and permeability, and mineral recovery from geothermal fluids.

Rock-water Interactions in Hot Dry Rock Geothermal Systems

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Publisher :
ISBN 13 :
Total Pages : 270 pages
Book Rating : 4.:/5 (114 download)

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Book Synopsis Rock-water Interactions in Hot Dry Rock Geothermal Systems by : Charles Owen Grigsby

Download or read book Rock-water Interactions in Hot Dry Rock Geothermal Systems written by Charles Owen Grigsby and published by . This book was released on 1983 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Yellowstone as an Analog for Thermal-Hydrological-Chemical Processes at Yucca Mountain

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ISBN 13 :
Total Pages : 2 pages
Book Rating : 4.:/5 (684 download)

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Book Synopsis Yellowstone as an Analog for Thermal-Hydrological-Chemical Processes at Yucca Mountain by :

Download or read book Yellowstone as an Analog for Thermal-Hydrological-Chemical Processes at Yucca Mountain written by and published by . This book was released on 2001 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt: Enhanced water-rock interaction resulting from the emplacement of heat-generating nuclear waste in the potential geologic repository at Yucca Mountain, Nevada, may result in changes to fluid flow (resulting from mineral dissolution and precipitation in condensation and boiling zones, respectively). Studies of water-rock interaction in active and fossil geothermal systems (natural analogs) provide evidence for changes in permeability and porosity resulting from thermal-hydrological-chemical (THC) processes. The objective of this research is to document the effects of coupled THC processes at Yellowstone and then examine how differences in scale could influence the impact that these processes may have on the Yucca Mountain system. Subsurface samples from Yellowstone National Park, one of the largest active geothermal systems in the world, contain some the best examples of hydrothermal self-sealing found in geothermal systems. We selected core samples from two USGS research drill holes from the transition zone between conductive and convective portions of the geothermal system (where sealing was reported to occur). We analyzed the core, measuring the permeability, porosity, and grain density of selected samples to evaluate how lithology, texture, and degree of hydrothermal alteration influence matrix and fracture permeability.

Water-rhyolite Interaction in the Yellowstone Hydrothermal System

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ISBN 13 :
Total Pages : 430 pages
Book Rating : 4.:/5 (15 download)

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Book Synopsis Water-rhyolite Interaction in the Yellowstone Hydrothermal System by : Jeffrey Todd Cullen

Download or read book Water-rhyolite Interaction in the Yellowstone Hydrothermal System written by Jeffrey Todd Cullen and published by . This book was released on 2018 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: In caldera-hosted rhyolitic hydrothermal systems, thermal waters, which are expelled to the surface through geysers and hot springs, provide a window into the conditions of water-rock interaction and element source/transport pathways of the dissolved components. By conducting hydrothermal experiments, we can constrain element behaviors during water-rock (W-R) interaction which enhances our ability to accurately interpret natural thermal waters and thus gain insights into processes occurring at depth in the hydrothermal system. This dissertation focuses on constraining elemental and isotopic behaviors during water rock interactions under conditions appropriate of continental, rhyolitic-caldera-hosted hydrothermal systems; more specifically the Yellowstone Hydrothermal System. In Chapter 2, I conduct water-rhyolite experiments over a temperature range of 150°C-350°C to constrain element leaching behaviors at each temperature, the secondary minerals formed, and how the secondary minerals control the concentrations of certain essential proxy fluid-mobile trace elements (Cl, F, Br, Li, and B). The experiments show rhyolite obsidian is stable at T ≤ 250°C. No alteration occurs and F is mobilized readily out of the rock by hydration exchange reactions. Cl and B are not leached from the rock. At T ≥ 275 °C, the rhyolite is completely broken down and recrystallized to the zeolite, ferrierite. Fluorine has affinity for the zeolite and is removed from solution into this phase, whereas Cl and B are completely leached from the rock and remain in solution. Li is moderately fluid mobile over the entire temperature range. In Chapter 3, I investigate the Cl, Li, and B stable isotope behaviors of the experimental materials in order to determine whether these isotopes fractionate during water rock interaction. The experimental results are compared with natural Yellowstone thermal waters from Upper Geyser Basin (UGB). The results indicate that Cl and B isotopes fractionate negligibly during leaching and during precipitation of ferrierite at T ≥ 275 °C. 7Li is only preferentially released into solution during leaching at T ≤ 250°C. The Cl, Li, and B isotope compositions of Upper Geyser Basin (UGB) waters reflect the leaching from host rhyolites with little to no fractionation. Elemental ratios suggest a small fraction of Cl and perhaps Li are derived from a magmatic source. In Chapter 4, I generate aqueous geochemical data from an extensive suite of Yellowstone thermal waters we collected between 2014 and 2016 (n = 141) from 11 separate geyser basins/thermal areas in the Yellowstone Hydrothermal System to uncover chemical correlations between thermal areas and water types across the entire system. Data are in good agreement with the experimental results. delta37Cl, values are relatively uniform throughout, and indicate leaching from host rhyolites. In alkaline-chloride dominant thermal areas, delta7Li, and delta11B values indicate leaching of host rhyolites with minimal fractionation and/or interaction with preciously altered rhyolites. In acid-SO4 and mixed SO4-Cl areas, delta7Li, and delta11B values are consistent with fractionation due to interaction with secondary clay minerals. Higher resolution investigation of UGB thermal waters reveals spatial correlations with compositions and inferred reservoir equilibrium temperatures.

Comparing FRACHEM and TOUGHREACT for Reactive Transport Modelingof Brine-rock Interactions in Enhanced Geothermal Systems (EGS).

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (316 download)

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Book Synopsis Comparing FRACHEM and TOUGHREACT for Reactive Transport Modelingof Brine-rock Interactions in Enhanced Geothermal Systems (EGS). by : K. Pruess

Download or read book Comparing FRACHEM and TOUGHREACT for Reactive Transport Modelingof Brine-rock Interactions in Enhanced Geothermal Systems (EGS). written by K. Pruess and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Coupled modelling of fluid flow and reactive transport ingeothermal systems is challenging because of reservoir conditions such ashigh temperatures, elevated pressures and sometimes high salinities ofthe formation fluids. Thermal hydrological-chemical (THC) codes, such asFRACHEM and TOUGHREACT, have been developed to evaluate the long-termhydrothermal and chemical evolution of exploited reservoirs. In thisstudy, the two codes were applied to model the same geothermal reservoir, to forecast reservoir evolution using respective thermodynamic andkinetic input data. A recent (unreleased) TOUGHREACT version allows theuse of either an extended Debye-Hu?ckel or Pitzer activity model forcalculating activity coefficients, while FRACHEM was designed to use thePitzer formalism. Comparison of models results indicate that differencesin thermodynamic equilibrium constants, activity coefficients andkinetics models can result in significant differences in predictedmineral precipitation behaviour and reservoir-porosity evolution. Differences in the calculation schemes typically produce less differencein model outputs than differences in input thermodynamic and kineticdata, with model results being particularly sensitive to differences inion-interaction parameters for highsalinity systems.

Modeling Brine-rock Interactions in an Enhanced Geothermal Systemdeep Fractured Reservoir at Soultz-Sous-Forets (France)

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ISBN 13 :
Total Pages : pages
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Book Synopsis Modeling Brine-rock Interactions in an Enhanced Geothermal Systemdeep Fractured Reservoir at Soultz-Sous-Forets (France) by : Karsten Pruess

Download or read book Modeling Brine-rock Interactions in an Enhanced Geothermal Systemdeep Fractured Reservoir at Soultz-Sous-Forets (France) written by Karsten Pruess and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The modeling of coupled thermal, hydrological, and chemical (THC) processes in geothermal systems is complicated by reservoir conditions such as high temperatures, elevated pressures and sometimes the high salinity of the formation fluid. Coupled THC models have been developed and applied to the study of enhanced geothermal systems (EGS) to forecast the long-term evolution of reservoir properties and to determine how fluid circulation within a fractured reservoir can modify its rock properties. In this study, two simulators, FRACHEM and TOUGHREACT, specifically developed to investigate EGS, were applied to model the same geothermal reservoir and to forecast reservoir evolution using their respective thermodynamic and kinetic input data. First, we report the specifics of each of these two codes regarding the calculation of activity coefficients, equilibrium constants and mineral reaction rates. Comparisons of simulation results are then made for a Soultz-type geothermal fluid (ionic strength {approx}1.8 molal), with a recent (unreleased) version of TOUGHREACT using either an extended Debye-Hueckel or Pitzer model for calculating activity coefficients, and FRACHEM using the Pitzer model as well. Despite somewhat different calculation approaches and methodologies, we observe a reasonably good agreement for most of the investigated factors. Differences in the calculation schemes typically produce less difference in model outputs than differences in input thermodynamic and kinetic data, with model results being particularly sensitive to differences in ion-interaction parameters for activity coefficient models. Differences in input thermodynamic equilibrium constants, activity coefficients, and kinetics data yield differences in calculated pH and in predicted mineral precipitation behavior and reservoir-porosity evolution. When numerically cooling a Soultz-type geothermal fluid from 200 C (initially equilibrated with calcite at pH 4.9) to 20 C and suppressing mineral precipitation, pH values calculated with FRACHEM and TOUGHREACT/Debye-Hueckel decrease by up to half a pH unit, whereas pH values calculated with TOUGHREACT/Pitzer increase by a similar amount. As a result of these differences, calcite solubilities computed using the Pitzer formalism (the more accurate approach) are up to about 1.5 orders of magnitude lower. Because of differences in Pitzer ion-interaction parameters, the calcite solubility computed with TOUGHREACT/Pitzer is also typically about 0.5 orders of magnitude lower than that computed with FRACHEM, with the latter expected to be most accurate. In a second part of this investigation, both models were applied to model the evolution of a Soultz-type geothermal reservoir under high pressure and temperature conditions. By specifying initial conditions reflecting a reservoir fluid saturated with respect to calcite (a reasonable assumption based on field data), we found that THC reservoir simulations with the three models yield similar results, including similar trends and amounts of reservoir porosity decrease over time, thus pointing to the importance of model conceptualization. This study also highlights the critical effect of input thermodynamic data on the results of reactive transport simulations, most particularly for systems involving brines.

Geochemical Modelling of Water-rock Interactions in Hot Dry Rock Geothermal Reservoirs

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ISBN 13 :
Total Pages : 227 pages
Book Rating : 4.:/5 (122 download)

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Book Synopsis Geochemical Modelling of Water-rock Interactions in Hot Dry Rock Geothermal Reservoirs by : R. A. McCartney

Download or read book Geochemical Modelling of Water-rock Interactions in Hot Dry Rock Geothermal Reservoirs written by R. A. McCartney and published by . This book was released on 1988 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Simulation of Fluid-rock Interactions in a Geothermal Basin. Final Report. [QUAGMR (quasi-active Geothermal Reservoir)].

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ISBN 13 :
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Book Synopsis Simulation of Fluid-rock Interactions in a Geothermal Basin. Final Report. [QUAGMR (quasi-active Geothermal Reservoir)]. by :

Download or read book Simulation of Fluid-rock Interactions in a Geothermal Basin. Final Report. [QUAGMR (quasi-active Geothermal Reservoir)]. written by and published by . This book was released on 1975 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: General balance laws and constitutive relations are developed for convective hydrothermal geothermal reservoirs. A fully interacting rock-fluid system is considered; typical rock-fluid interactions involve momentum and energy transfer and the dependence of rock porosity and permeability upon the fluid and rock stresses. The mathematical model also includes multiphase (water/steam) effects. A simple analytical model is employed to study heat transfer into/or from a fluid moving in a porous medium. Numerical results show that for fluid velocities typical of geothermal systems (Reynolds number much less than 10), the fluid and the solid may be assumed to be in local thermal equilibrium. Mathematical formalism of Anderson and Jackson is utilized to derive a continuum species transport equation for flow in porous media; this method allows one to delineate, in a rigorous manner, the convective and diffusive mechanisms in the continuum representation of species transport. An existing computer program (QUAGMR) is applied to study upwelling of hot water from depth along a fault; the numerical results can be used to explain local temperature inversions occasionally observed in bore hole measurements.

Simulation of Fluid-rock Interactions in a Geothermal Basin

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ISBN 13 :
Total Pages : 128 pages
Book Rating : 4.:/5 (28 download)

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Book Synopsis Simulation of Fluid-rock Interactions in a Geothermal Basin by : S. K. Garg

Download or read book Simulation of Fluid-rock Interactions in a Geothermal Basin written by S. K. Garg and published by . This book was released on 1975 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: