Assessment of Chaves Low-Temperature CO2-Rich Geothermal System (N-Portugal) Using an Interdisciplinary Geosciences Approach

Geofluids ◽

10.1155/2019/1379093 ◽

2019 ◽

Vol 2019 ◽

pp. 1-24 ◽

Cited By ~ 3

Author(s):

J. M. Marques ◽

P. M. Carreira ◽

L. A. Aires-Barros ◽

F. A. Monteiro Santos ◽

M. Antunes da Silva ◽

...

Keyword(s):

Low Temperature ◽

Geophysical Methods ◽

Interdisciplinary Approach ◽

Mineral Waters ◽

Added Value ◽

Granitic Rocks ◽

Geothermal System ◽

Geothermal Waters ◽

Study Region ◽

Rock Formations

This paper reviews the results of a multi- and interdisciplinary approach, including geological, geomorphological, tectonic, geochemical, isotopic, and geophysical studies, on the assessment of a Chaves low-temperature (77°C) CO2-rich geothermal system, occurring in the northern part of the Portuguese mainland. This low-temperature geothermal system is ascribed to an important NNE-trending fault, and the geomorphology is dominated by the “Chaves Depression,” a graben whose axis is oriented NNE-SSW. The study region is situated in the tectonic unit of the Middle Galicia/Trás-os-Montes subzone of the Central Iberian Zone of the Hesperic Massif comprising mainly Variscan granites and Paleozoic metasediments. Chaves low-temperature CO2-rich geothermal waters belong to the Na-HCO3-CO2-rich-type waters, with pH≈7. Total dissolved solids range between 1600 and 1850 mg/L. Free CO2 is of about 500 mg/L. The results of SiO2 and K2/Mg geothermometers give estimations of reservoir temperature around 120°C. δ18O and δ2H values of Chaves low-temperature CO2-rich geothermal waters indicate a meteoric origin for these waters. No significant 18O-shift was observed, consistent with the results from the chemical geothermometry. δ13CCO2 values vary between −7.2 and −5.1‰ vs. V-PDB, and CO2/3He ratios range from 1×108 to 1×109, indicating a deep (upper mantle) source for the CO2. 3He/4He ratios are of about 0.9 (R/Ra). The Chaves low-temperature CO2-rich geothermal waters present similar 87Sr/86Sr ratios (between 0.728035 and 0.716713) to those of the plagioclases from granitic rocks (between 0.72087 and 0.71261) suggesting that water mineralization is strongly ascribed to Na-plagioclase hydrolysis. Geophysical methods (e.g., resistivity and AMT soundings) detected conductive zones concentrated in the central part of the Chaves graben as a result of temperature combined with the salinity of the Chaves low-temperature CO2-rich geothermal waters in fractured and permeable rock formations. This paper demonstrates the added value of an integrated and multi- and interdisciplinary approach for a given geothermal site characterization, which could be useful for other case studies linking the assessment of low-temperature CO2-rich geothermal waters and cold CO2-rich mineral waters emerging in a same region.

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Geochemical features of the geothermal and mineral waters from Apuseni Mountains, Romania

10.5194/egusphere-egu2020-583 ◽

2020 ◽

Author(s):

Alin-Marius Nicula ◽

Artur Ionescu ◽

Cristian-Ioan Pop ◽

Carmen Roba ◽

Walter D’Alessandro ◽

...

Keyword(s):

Heavy Metal ◽

Pannonian Basin ◽

Water Sources ◽

Mineral Waters ◽

Thermal Waters ◽

Geothermal Waters ◽

Study Region ◽

Apuseni Mountains ◽

The North ◽

North Western

Geochemical features of the geothermal and mineral waters from Apuseni Mountains, RomaniaAlin-Marius Nicula1, Artur Ionescu1,2, Cristian-Ioan Pop1, Carmen Roba1, Walter D&#8217;Alessandro3, Ferenc Lazar Forray4, Iancu Oraseanu5, Calin Baciu1&#160;1Babes-Bolyai University, Faculty of Environmental Science and Engineering, Str. Fantanele nr. 30, 400294, Cluj-Napoca, Romania ([email protected])2University of Perugia, Department of Physics and Geology, Via A. Pascoli 06123, Perugia, Italy3Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Palermo, Via Ugo la Malfa, 153,90146 Palermo, Italy4Department of Geology, Babes-Bolyai University, Kogalniceanu 1, 400084 Cluj-Napoca, Romania5Romanian Association of Hydrogeologists, Bucuresti, Romania&#160;The Apuseni Mountains are located in the western part of Romania and separate the Pannonian Basin from the Transylvanian Basin. These mountains are famous and intensely studied for their important non-ferrous metal resources. Few data were published about the geothermal potential of this area. More works have been dedicated to mineral waters, while the geothermal waters are only briefly described, without sufficient emphasis on them. The current research is focusing on the two categories, cold mineral and geothermal water in the Apuseni Mountains, compared to the surrounding areas, in order to better understand their genesis and the general context of the geothermalism in the study region. A preliminary survey of these waters was done in 2019 taking water and gas samples from 41 sources.The pH varies between 6.00 and 9.02 and, the lowest values have been measured in the CO2-rich waters of the Southern Apuseni Mountains. Water temperatures vary between 11.1 &#226;&#151;&#139;C and 81 &#226;&#151;&#139;C. In the southern part of the Apuseni Mountains, the geothermal waters are of the calcium bicarbonate type (Ca-HCO3), while in the north-western part, the sodium bicarbonate type (Na-HCO3) is more common. The water sources from the north-western part are close to the Pannonian Basin and show features comparable to the thermal waters of this basin. Conductivity values show significant variations between 142 and 2040 &#181;S/cm, but regional homogeneities were observed. The highest concentration of bicarbonate was measured in one of the localities of the northern study area (Beiu&#197;&#159; Depression - 3318.4 mg/L). The dissolved heavy metal concentrations (Zn, Pb, Cd, Cr, Ni, Cu, Fe) in the water samples were also measured. For all the investigated waters, the heavy metal content was low. The highest concentrations were recorded for Fe 342.90 &#181;g/L and Zn 86.14 &#181;g/L. The isotopic data (&#948;18O and &#948;2H) demonstrate the meteoric origin of the thermal waters.Some springs and wells release free gases. The gas chromatographic analyses show the prevalence of N2 and CO2, with minor amounts of CH4 in the water sources close to the Pannonian Basin. The isotope composition of Helium shows values between 0.9 and 2.18 R/Ra indicating a prevailing crustal source with a significant mantle component. In the case of &#948;13C-CO2 the values range between -12.7 and -6.1 &#8240; vs.V-PDB, indicating that the CO2 originates possibly from a limestone source.

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Revised hydrogeological model of the hydrothermal system Waiwera (New Zealand)

10.5194/egusphere-egu21-12196 ◽

2021 ◽

Author(s):

Andreas Grafe ◽

Thomas Kempka ◽

Michael Schneider ◽

Michael Kühn

Keyword(s):

Water Management ◽

New Zealand ◽

Water Level ◽

Hot Water ◽

Hydrogeology Journal ◽

Natural State ◽

Geothermal System ◽

Geological Model ◽

Species Transport ◽

Study Region

The geothermal hot water reservoir underlying the coastal township of Waiwera, northern Auckland Region, New Zealand, has been commercially utilized since 1863. The reservoir is complex in nature, as it is controlled by several coupled processes, namely flow, heat transfer and species transport. At the base of the aquifer, geothermal water of around 50&#176;C enters. Meanwhile, freshwater percolates from the west and saltwater penetrates from the sea in the east. Understanding of the system&#8217;s dynamics is vital, as decades of unregulated, excessive abstraction resulted in the loss of previously artesian conditions. To protect the reservoir and secure the livelihoods of businesses, a Water Management Plan by The Auckland Regional Council was declared in the 1980s [1]. In attempts to describe the complex dynamics of the reservoir system with the goal of supplementing sustainable decision-making, studies in the past decades have brought forth several predictive models [2]. These models ranged from being purely data driven statistical [3] to fully coupled process simulations [1]. Our objective was to improve upon previous numerical models by introducing an updated geological model, in which the findings of a recently undertaken field campaign were integrated [4]. A static 2D Model was firstly reconstructed and verified to earlier multivariate regression model results. Furthermore, the model was expanded spatially into the third dimension. In difference to previous models, the influence of basic geologic structures and the sea water level onto the geothermal system are accounted for. Notably, the orientation of dipped horizontal layers as well as major regional faults are implemented from updated field data [4]. Additionally, the model now includes the regional topography extracted from a digital elevation model and further combined with the coastal bathymetry. Parameters relating to the hydrogeological properties of the strata along with the thermophysical properties of water with respect to depth were applied. Lastly, the catchment area and water balance of the study region are considered. The simulation results provide new insights on the geothermal reservoir&#8217;s natural state. Numerical simulations considering coupled fluid flow as well as heat and species transport have been carried out using the in-house TRANSport Simulation Environment [5], which has been previously verified against different density-driven flow benchmarks [1]. The revised geological model improves the agreement between observations and simulations in view of the timely and spatial development of water level, temperature and species concentrations, and thus enables more reliable predictions required for water management planning. [1] K&#252;hn M., St&#246;fen H. (2005): &#160; &#160; &#160; Hydrogeology Journal, 13, 606&#8211;626, &#160; &#160; &#160; https://doi.org/10.1007/s10040-004-0377-6 [2] K&#252;hn M., Altmannsberger C. (2016): &#160; &#160; &#160; Energy Procedia, 97, 403-410, &#160; &#160; &#160; https://doi.org/10.1016/j.egypro.2016.10.034 [3] K&#252;hn M., Sch&#246;ne T. (2017): &#160; &#160; &#160; Energy Procedia, 125, 571-579, &#160; &#160; &#160; https://doi.org/10.1016/j.egypro.2017.08.196 [4] Pr&#228;g M., Becker I., Hilgers C., Walter T.R., K&#252;hn M. (2020): &#160; &#160; &#160; Advances in Geosciences, 54, 165-171, &#160; &#160; &#160; https://doi.org/10.5194/adgeo-54-165-2020 [5] Kempka T. (2020): &#160; &#160; &#160; Adv. Geosci., 54, 67&#8211;77, &#160; &#160; &#160; https://doi.org/10.5194/adgeo-54-67-2020

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Seismic Methods in Geothermal Water Resource Exploration: Case Study from Łódź Trough, Central Part of Poland

Geofluids ◽

10.1155/2019/3052806 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

Tomasz Maćkowski ◽

Anna Sowiżdżał ◽

Anna Wachowicz-Pyzik

Keyword(s):

Estimation Error ◽

Geophysical Methods ◽

Petroleum Industry ◽

Geological Structure ◽

Seismic Survey ◽

Energy Potential ◽

Geothermal Resources ◽

Geothermal Waters ◽

Seismic Methods ◽

Geophysical Surveys

The geothermal waters constitute a specific type of water resources, very important from the point of view of their thermal energy potential. This potential, when utilized, supplies an ecological and renewable energy, which, after effective development, brings many environmental, social, and industrial benefits. The key element of any geothermal investment is the proper location of geothermal installation, which would guarantee the relevant hydrogeothermal parameters of the water intake. Hence, many studies and analyses are carried out in order to characterize the reservoir parameters, including the integrated geophysical methods. For decades, the geophysical surveys have been the trusty recognition methods of geological structure and petrophysical parameters of rock formations. Thus, they are widely applied by petroleum industry in exploration of conventional and unconventional (shale gas/oil, tight gas) hydrocarbon deposits. Advances in geophysical methods extended their applicability to many other scientific and industrial branches as, e.g., the seismic survey used in studies of geothermal aquifers. The following paper presents the opportunities provided by seismic methods applied to studies of geothermal resources in the central Poland where the geothermal waters are reservoired in both the Lower Cretaceous and the Lower Jurassic sedimentary successions. The presented results are obtained from a network of seismic profiles. An important advantage of the seismic survey is that they may support the selection of an optimal location of geothermal investment and determination of the geometry of geothermal aquifer. Furthermore, the application of geophysical methods can significantly contribute to the reduction of estimation error of groundwater reservoir temperature.

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Low Temperature Alterations in Granitic Rocks from the Siljan Ring Structure, Central Sweden

Deep Drilling in Crystalline Bedrock - Exploration of the Deep Continental Crust ◽

10.1007/978-3-642-73452-6_19 ◽

1988 ◽

pp. 209-216 ◽

Cited By ~ 2

Author(s):

A. A. Aldahan ◽

K. Ramseyer ◽

S. Morad ◽

B. Collini

Keyword(s):

Low Temperature ◽

Ring Structure ◽

Granitic Rocks

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Hydrogeochemical Characteristics and Genesis of Geothermal Water from the Ganzi Geothermal Field, Eastern Tibetan Plateau

Water ◽

10.3390/w11081631 ◽

2019 ◽

Vol 11 (8) ◽

pp. 1631

Author(s):

Fan ◽

Pang ◽

Liao ◽

Tian ◽

Hao ◽

...

Keyword(s):

High Temperature ◽

Tibetan Plateau ◽

Heat Source ◽

Chloride Concentration ◽

Geothermal Field ◽

Geothermal Water ◽

Helium Isotope ◽

Geothermal System ◽

The Tibetan Plateau ◽

Geothermal Waters

The Ganzi geothermal field, located in the eastern sector of the Himalayan geothermal belt, is full of high-temperature surface manifestations. However, the geothermal potential has not been assessed so far. The hydrochemical and gas isotopic characteristics have been investigated in this study to determine the geochemical processes involved in the formation of the geothermal water. On the basis of δ18O and δD values, the geothermal waters originate from snow and glacier melt water. The water chemistry type is dominated by HCO3-Na, which is mainly derived from water-CO2-silicate interactions, as also indicated by the 87Sr/86Sr ratios (0.714098–0.716888). Based on Cl-enthalpy mixing model, the chloride concentration of the deep geothermal fluid is 37 mg/L, which is lower than that of the existing magmatic heat source area. The estimated reservoir temperature ranges from 180–210 °C. Carbon isotope data demonstrate that the CO2 mainly originates from marine limestone metamorphism, with a fraction of 74–86%. The helium isotope ratio is 0.17–0.39 Ra, indicating that the He mainly comes from atmospheric and crustal sources, and no more than 5% comes from a mantle source. According to this evidence, we propose that there is no magmatic heat source below the Ganzi geothermal field, making it a distinctive type of high-temperature geothermal system on the Tibetan Plateau.

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Insights from the Sustainability Monitoring Tool SUMINISTRO Applied to a Case Study System of Prospective Wood-Based Industry Networks in Central Germany

Sustainability ◽

10.3390/su12093896 ◽

2020 ◽

Vol 12 (9) ◽

pp. 3896

Author(s):

Jakob Hildebrandt ◽

Alberto Bezama ◽

Daniela Thrän

Keyword(s):

Value Added ◽

Life Cycle Management ◽

Positive Influence ◽

Added Value ◽

Monitoring Tool ◽

Study Region ◽

Central Germany ◽

Stakeholder Perspectives ◽

Integrative Assessment

Bioeconomy regions are a young concept representing emerging amalgamation points for the implementation of cross-sectoral value-added chains. When sustainable bioeconomy strategies are rolled out, their proof-of-concept implies that industrial R&D activities should lead to impact decoupling and that the valorization of locally available lignocellulosic biomass has to contribute to an increase in added value. Furthermore, regional co-benefits for society and a positive influence on local environmental and socioeconomic conditions are major factors. The fulfillment of these strategic goals would be a milestone achievement when progressing from the blueprint development and the road-mapping stage towards socially accepted and sustainable wood-based bioeconomy strategies. For regional industrial and science stakeholders who run pilot facilities for process upscaling and for energy and material flow integration, this requires well-orchestrated integrative processes, which go beyond conventional “Life Cycle Management” approaches. It is obvious that assessing and monitoring such integrative systems will have to account for different stakeholder perspectives and for detailed technology deployment and resource conversion scenarios. Applying a sustainability index methodology in a case study region must include an evaluation of the whole supply chain and the process networks associated with the characteristic products of the evaluated region. To date, no such integrative assessment methods exist in the literature. Therefore, the aim of this paper is to lay out, on the basis of a practical example in the case study region of Central Germany, an assessment of the sustainability level of wood-based bioeconomy networks by applying the Sustainability Monitoring Tool -SUMINISTRO”- to examine regional bio-based industry networks.

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Unveiling the 3D undercover structure of a Precambrian intrusive complex by integrating airborne magnetic and gravity gradient data into 3D quasi-geology model building

Interpretation ◽

10.1190/int-2019-0273.1 ◽

2020 ◽

Vol 8 (4) ◽

pp. SS15-SS29 ◽

Cited By ~ 1

Author(s):

Jiajia Sun ◽

Aline Tavares Melo ◽

Jae Deok Kim ◽

Xiaolong Wei

Keyword(s):

High Resolution ◽

Model Building ◽

Country Rock ◽

Joint Inversion ◽

Sedimentary Cover ◽

Geophysical Methods ◽

Added Value ◽

Gravity Gradient ◽

Airborne Magnetic

Mineral exploration under a thick sedimentary cover naturally relies on geophysical methods. We have used high-resolution airborne magnetic and gravity gradient data over northeast Iowa to characterize the geology of the concealed Precambrian rocks and evaluate the prospectivity of mineral deposits. Previous researchers have interpreted the magnetic and gravity gradient data in the form of a 2D geologic map of the Precambrian basement rocks, which provides important geophysical constraints on the geologic history and mineral potentials over the Decorah area located in the northeast of Iowa. However, their interpretations are based on 2D data maps and are limited to the two horizontal dimensions. To fully tap into the rich information contained in the high-resolution airborne geophysical data, and to further our understanding of the undercover geology, we have performed separate and joint inversions of magnetic and gravity gradient data to obtain 3D density contrast models and 3D susceptibility models, based on which we carried out geology differentiation. Based on separately inverted physical property values, we have identified 10 geologic units and their spatial distributions in 3D which are all summarized in a 3D quasi-geology model. The extension of 2D geologic interpretation to 3D allows for the discovery of four previously unidentified geologic units, a more detailed classification of the Yavapai country rock, and the identification of the highly anomalous core of the mafic intrusions. Joint inversion allows for the classification of a few geologic units further into several subclasses. We have demonstrated the added value of the construction of a 3D quasi-geology model based on 3D separate and joint inversions.

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Geophysical mapping of palsa peatland permafrost

The Cryosphere ◽

10.5194/tc-9-465-2015 ◽

2015 ◽

Vol 9 (2) ◽

pp. 465-478 ◽

Cited By ~ 26

Author(s):

Y. Sjöberg ◽

P. Marklund ◽

R. Pettersson ◽

S. W. Lyon

Keyword(s):

Geophysical Methods ◽

Permafrost Zone ◽

Added Value ◽

Spatial Distributions ◽

Resistivity Tomography ◽

Discontinuous Permafrost ◽

Ice Content ◽

Ground Penetrating ◽

Biogeochemical Hotspots ◽

Geophysical Mapping

Abstract. Permafrost peatlands are hydrological and biogeochemical hotspots in the discontinuous permafrost zone. Non-intrusive geophysical methods offer a possibility to map current permafrost spatial distributions in these environments. In this study, we estimate the depths to the permafrost table and base across a peatland in northern Sweden, using ground penetrating radar and electrical resistivity tomography. Seasonal thaw frost tables (at ~0.5 m depth), taliks (2.1–6.7 m deep), and the permafrost base (at ~16 m depth) could be detected. Higher occurrences of taliks were discovered at locations with a lower relative height of permafrost landforms, which is indicative of lower ground ice content at these locations. These results highlight the added value of combining geophysical techniques for assessing spatial distributions of permafrost within the rapidly changing sporadic permafrost zone. For example, based on a back-of-the-envelope calculation for the site considered here, we estimated that the permafrost could thaw completely within the next 3 centuries. Thus there is a clear need to benchmark current permafrost distributions and characteristics, particularly in under studied regions of the pan-Arctic.

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Integration of geophysical methods and fractures study for the Vallès geothermal system characterization (NE Spain)

10.5194/egusphere-egu2020-6769 ◽

2020 ◽

Author(s):

Gemma Mitjanas ◽

Juanjo Ledo ◽

Pilar Queralt ◽

Gemma Alías ◽

Perla Piña ◽

...

Keyword(s):

Fluid Flow ◽

Geophysical Methods ◽

Normal Fault ◽

Hot Water ◽

Fault System ◽

Geothermal System ◽

Thin Sections ◽

Main Structure ◽

Geological Map ◽

Ne Spain

The Vall&#232;s geothermal system is located in the Catalan Coastal Ranges (CCR) (NE Spain). The CCR are formed by horst and graben structures limited by NE-SW and ENE-WSW striking normal faults, developed during the opening of the Valencia Trough (northwestern Mediterranean) (Gaspar-Escribano et al., 2004). In the Vall&#232;s Basin area, the thermal anomaly is located in the northeastern horst-graben limit, where a highly fractured Hercynian granodiorite is in contact with Miocene rocks by a major normal fault. This main structure seems to control the heat and the hot-water flow, nevertheless, the geological structure of this area, as well as the role of the Vall&#232;s normal fault, is poorly understood.Magnetotellurics and gravity methods together with a detailed geological map have been applied in this area to understand the main structure. Although the geophysical part makes up most of the study, we are also elaborating a detailed geological map of the area, making a fractures study at different scales. We are working with DEM alignments analysis, and fractures study from outcrops and thin sections.Our preliminary results in gravity show a strong gravity gradient in the NE-SW Vall&#232;s half-graben system and the recent MT profiles image the main fault of that system (Vall&#232;s normal fault). These results show a basin geometry with the major thickness of the basin towards the depocenter, disagreeing with the roll-over geometry assumed in previous works.Interpretations of the fractures study, together with geophysical data and models, have allowed a preliminary characterization of damage zones associated with the fault system, which are directly related to the fluid flow and the hot springs. The nature of this damage zones could be related to relay ramps, commonly regarded as efficient conduits for fluid flow (Fossen and Rotevatn, 2016).

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EXPERIENCING HERITAGE DYNAMIC THROUGH VISUALIZATION

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-2-w11-715-2019 ◽

2019 ◽

Vol XLII-2/W11 ◽

pp. 715-719

Author(s):

N. Lecci ◽

F. Prodi ◽

F. Trovatelli ◽

A. Vezzi

Keyword(s):

3D Model ◽

New Technologies ◽

Spatial Perception ◽

Interdisciplinary Approach ◽

Written Language ◽

Reference Points ◽

Added Value ◽

General View ◽

The Public ◽

Neutral Base

Abstract. The present article aims to consider the added value attached to the usage of new technologies in a project aimed to study heritage. Indeed, multimedia devices could be used to create representations useful to develop and disseminate information integrating the architectural and territorial framework and to reach a general understanding.The processed data come from a research project, based on an interdisciplinary approach, address to the study of medieval buildings in Armenia, Vayots Dzor region, with the aim of studying and understanding the cultural heritage.Three different technologies are used to visualize and disseminate the results of the analyses carried out: the video, the hologram, and the virtual reality. These digital visualization methods enable experts to make the topics investigated accessible and comprehensible to a wider general public with a didactic and informative aim.The solid 3D-model of the site allows to virtually reproduce the reality and to provide a spatial perception of the site. Indeed, it is a neutral base, represents the morphological conformation and settlements, a landscape whose reference points are easily identified with the historical architectures, helping the public and spectators to get oriented inside the territory. These methods of representation allow to move from general view to particular, or to a different frame appropriate to the addressed topic. Thus, it binds the scientific research with the visual part, and enable communication, even in a context where it is difficult to use a common spoken or written language.

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