Sven Fuchs

Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences · Geosystems (Section Geoenergy)

Mesozoic sandstone aquifers in the North German Basin offer significant potential to provide green and sustainable geothermal heat as well as large-scale storage of heat or chill. The determination of geothermal and subsurface heat storage potentials is still afflicted with obstacles due to sparse and partly uncertain subsurface data. Relevant data...

The data publication contains the compilation of global heat-flow data by the International Heat Flow Commission (IHFC; www.ihfc-iugg.org) of the International Association of Seismology and Physics of the Earth's Interior (IASPEI). The presented data update 2023 contains data generated between 1939 and 2022 and constitutes the first intermediate up...

A public database of quality assured and vertified terrestrial heat flow measurments maintained by the International Heat Flow Commisison. Accessible at https://ihfc-iugg.org/products/global-heat-flow-database

Das Weltwärmestrom Datenbank Projekt setzt sich als Ziel eine neue Forschungsdateninfrastruktur (Web Portal) für terrestrische Wärmestromdaten zu entwickeln. Über die letzten Jahrzehnte ist eine umfangreiche, globale Datensammlung zum Thema Wärmestrom entstanden, welche über eine zentrale Anlaufstelle im Internet durch Einhaltung der FAIR und OPEN...

The accurate estimation of temperature distribution in the earth's crust and modeling of heat-related processes in geodynamics requires knowledge of the thermal conductivity of plutonic rocks. This study compiled an extensive dataset of 530 representative plutonic rock samples, including thermal conductivity, major oxide composition and (for two su...

Surface Heat flow (HF) can be calculated from the accumulation of radiogenic heat production (RHP) of arbitrarily subdivided thin layers of the crust and the residual HF. However, geothermal studies of scientific drilling projects around the world do not have clear vertical correspondence between HF and RHP, which has created a great controversy fo...

Svalbard is a High Arctic Archipelago at 74-81 • N and 15-35 • E under the sovereignty of Norway. All settlements in Svalbard, including the capital of Longyearbyen (population 2400), currently have isolated energy systems with coal or diesel as the main energy source. Geothermal energy is considered as a possible alternative for electricity produc...

Geothermal Resources and ATES Potential of Mesozoic Reservoirs in the North German Basin

This paper presents the results of a revision of the data on terrestrial heat flow in Germany, termed here as heat-flow density (HFD). The heat-flow values are considered as surface heat flow (qs) sensu stricto. The study is part of the ongoing reassessment of the Global Heat Flow Database organized by the International Heat Flow Commission (IHFC)....

Geothermal heat flow is inferred from the gradient of temperature values in boreholes or short-penetration probe measurements. Such measurements are expensive and logistically challenging in remote locations and, therefore, often targeted to regions of economic interest. As a result, measurements are not distributed evenly. Some tectonic, geologic...

Geothermal heat flow is commonly inferred from the gradient of temperature values in boreholes. Such measurements are expensive and logistically challenging in remote locations and, therefore, often targeted to regions of economic interest. As a result, measurements are not distributed evenly. Some tectonic, geologic and even topographic settings a...

We compile and analyze all available geothermal heat flow measurements collected in and around Greenland into a new database of 419 sites and generate an accompanying spatial map. This database includes 290 sites previously reported by the International Heat Flow Commission (IHFC), for which we now standardize measurement and metadata quality. This...

We compile, analyse and map all available geothermal heat flow measurements collected in and around Greenland into a new database of 419 sites and generate an accompanying spatial map. This database includes 290 sites previously reported by the International Heat Flow Commission (IHFC), for which we now standardize measurement and metadata quality....

This data publication (data download via: http://heatflow.ihfc-iugg.org/data) contains the compilation of global heat-flow data by the International Heat Flow Commission (IHFC; http://www.ihfc-iugg.org/) of the International Association of Seismology and Physics of the Earth's Interior (IASPEI). The presented data release 2021 contains data generat...

International Journal of Terrestrial Heat Flow and Applied Geothermics 4(1), 2021, 1-14; ISSN: 2595-4180 Periodic revisions of the Global Heat Flow Database (GHFD) take place under the auspices of the International Heat Flow Commission (IHFC) of the International Association of Seismology and Physics of the Earth's Interior (IASPEI). A growing numb...

Understanding the thermal behavior of nonsteady state subsurface geosystems, when temperature changes over time, requires knowledge on the speed of heat propagation and, thus, of the rock's thermal diffusivity as essential thermo‐physical parameter. Mixing models are commonly used to describe thermo‐physical properties of polymineralic rocks. A the...

The paper addresses the effects of pressure (P) and temperature (T) on thermal conductivity (λ) applied to crustal geotherms. A subset of the ca. 50 experimentally derived numerical P-T relations available in literature for typical crustal rock types was selected for this purpose. The relations comprise those from physical-contact laboratory method...

Rund die Hälfte der in Deutschland verbrauchten Energie entfällt auf den Wärmebedarf. Ein Großteil davon muss in urbanen Räumen bereitgestellt werden, für welche eine ortsnahe Energiebereitstellung mit geringen Transportverlusten wünschenswert erscheint. Geothermisch gewonnene Energie hat hier das Potential, eine Grundlastversorgung zu gewährleiste...

Precise knowledge of the subsurface thermal field plays a key role in the assessment of geothermal targets. Unfortunately, deep underground temperature data is generally scarce and a matter of research. To achieve first estimates for subsurface temperatures, steady‑state conductive thermal modeling is commonly applied. Thereby the rock thermal cond...

We present a 3D numerical crustal temperature model with inverse optimisation methodology and analyse the present-day conductive thermal field of the Danish onshore subsurface. The model is based on a comprehensive analysis and interpretation of borehole and well-log data for thermal and petrophysical rock properties and their regional variability...

The terrestrial heat flow constitutes one of the most important parameters to understand global geodynamic processes. In addition, it is indispensable for temperature models to assess geothermal resources. The German heat-flow data, which are part of the IHFC global heat flow database, date back to the 1970 years. Besides the fact that newer publis...

Subsurface temperature distributions affect important physical properties and processes. Temperatures depend not only on heat flow, but also on thermal conductivity. We have performed a sensitivity study for two depth scales, to study the effect on subsurface temperature in a compositionally variable crust by applying common p/T corrections to ther...

Paleoclimatic effects may still influence the present day subsurface temperature distribution and therefore the heat flow density calculated in affected depth levels. Cooling of several degrees Celsius into depths of up to 1.5 – 2 km were reported for areas which were strongly affected by the Pleistocene ice ages (e.g. Canada, Poland, and Denmark)....

From the Danish "DSF Geotermi project", we present the results of a 4D numerical crustal temperature model conducted to analyze the present-day temperature and heat-flow field of onshore Denmark, including large parts of the Danish Basin, the northernmost part of the North German Basin and the Sorgenfrei-Tornquist Zone. An extensive analysis of bor...

Genaue Kenntnisse des Verhaltens thermischer Gesteinseigenschaften unter in-situ Temperatur-, Druck-, und Fluidbedingungen sind unabdingbar für eine Reihe von wissenschaftlichen Anwendungen oder technologischen Nutzungen des geologischen Untergrundes (bspw. Geothermie zur Bereitstellung von Wärme-und Strom). In den erbohrbaren und wirtschaftlich nu...

Thermal conductivity (λ) is an essential physical property of minerals and rocks and fundamental in constraining the thermal field of the lithosphere. In case that adequate samples to measure λ are not available, it could be indirectly inferred from calculation. One of the most widely applied indirect methods for rocks involve modal mineralogy and...

Citation This data is freely available under a Creative Commons Attribution 4.0 International (CC-BY 4.0) Licence. When using the data please cite is like: Fuchs, Sven; Förster, Hans-Jürgen; Braune, Kathleen; Förster, Andrea (2018): Calculation of thermal conductivity of low-porous igneous rocks from modal mineralogy. GFZ Data Services. This data s...

Knowledge of the subsurface temperature field is paramount in the exploration of resources, such as hydrocarbons and geothermal energy. The terrestrial heat flow representing the conductive thermal field is a crucial parameter in such a characterization. It is determined from measured borehole temperature (temperature gradient) and rock thermal con...

The disposal of radioactive waste is a topic with huge social importance. Understanding the complex geological, geophysical and geochemical conditions is indispensable for the long-term stability and the safe operation of subsurface nuclear waste repositories, regardless whether they are in salt rock, clay or granitoids. In this context, the subsur...

Detailed knowledge of in situ formation thermal properties is a prerequisite for accurate temperature predictions from geothermal models of sedimentary basins. The value and regional variability of such formation thermal properties generally receive little attention: very few attention in petrophysical and even less in modelling studies. Consequent...

Accurate knowledge of in-situ thermal rock properties typical for the conditions in the Earth subsurface is indispensable for many applications in Earth science. At drillable depth, the pressure and temperature and thus its effect on rock thermal properties diverge strongly from those measured under ambient conditions in the laboratory. As the majo...

The Danish subsurface provides a large potential for the use of low-enthalpy geothermal heat and thereby to change the national district heating structure by providing a base load to the system. In the past decade, new exploration and research campaigns have been performed to remove geological, technical and commercial obstacles for a significant u...

Die Aussagekraft geohydraulischer Berechnungen hängt direkt von der genauen Kenntnis der hydraulischen Gesteinseigenschaften und deren Verteilung im Untergrund ab. Der Porenraum eines Lockergesteins bestimmt mit seinen unterschiedlich wirkenden Anteilen maßgeblich die wirksamen Grundwasserströmungsprozesse. Zur analytischen oder modellgestützten Be...

We performed a thermal-modelling scenario analysis in which we demonstrate how the use of both different parameter input type (from literature, lithology and well logs) and parameter input style (constant or spatially varying layer values) affects model temperature predictions in sedimentary basins. To conduct the scenario analysis, rock thermal pr...

Calculation of geotherms, reflecting steady-state heat conduction, is dependent on surface heat flow, the compositional model of the crust, and its thermo-physical properties, such as thermal conductivity (k) and radiogenic heat production (H). Available global geotherms are afflicted with uncertainties associated with the simplification of the cru...

Focus on the utilization of geothermal energy as a sustainable energy source has resulted in extensive geothermal exploration activities with a demand for procedures for obtaining reliable information on subsurface temperatures and thermal resources. Subsurface thermal information is basically obtained from two different sources: direct observation...

The calculation of temperature and heat-flow-density profiles in boreholes requires reliable values of rock thermal conductivity with depth. We developed a new approach for the indirect determination of thermal conductivity from standard geophysical well logs, which massively enlarges the available databases of subsurface rock conductivities beyond...

Translated title: 'Estimation of porosity from hydraulic conductivity and uniformity coefficient: a review' ### This paper comprises a review of the 13 studies that have been proposed for the derivation of porosity, effective porosity and/or specific yield from grain size distributions (Lejbenson 1947; Istomina 1957; Beyer 1964; Hennig 1966; Golf...

We present a 3D numerical crustal temperature model and analyze the present-day geothermal field of onshore Den-mark, including parts of the Danish Basin, the northernmost part of the North German Basin and the Sorgenfrei-Tornquist Zone. An extensive analysis of borehole and well-log data on a basin scale is conducted to derive the model parameteri...

Knowledge of structural, hydraulic and thermal conditions of the subsurface is fundamental for the planning and use of hydrothermal energy. In the framework of a project under the Danish Research program 'Sustainable Energy and Environment' funded by the 'Danish Agency for Science, Technology and Innovation', fundamental geological and geophysical...

Die Aussagekraft numerischer Temperaturmodelle für geodynamische oder nutzungsbezogenen Analysen der Erdkruste hängt direkt von der genauen Kenntnis der thermischer Gesteinseigenschaften im Untergrund ab. Üblicherweise werden diese an Gesteinsproben im Labor bestimmt, was die Verfügbarkeit der Messergebnisse auf wenige gekernte Bohrungsabschnitte b...

We present a 3D numerical crustal temperature model and analyse the present-day conductive thermal field of the Danish-German border region. The model region covers the northernmost part of the North German Basin, a transition zone between the deep-reaching sedimentary rocks of the Glückstadt Graben (including complex salt structures) and the shall...

The subsurface temperature field and the geothermal conditions in sedimentary basins are frequently examined by using numerical thermal models. For those models, detailed knowledge of rock thermal properties are paramount for a reliable parameterization of layer properties and boundary conditions. Despite the state-of-the-art in other research fiel...

Numerical temperature models generated for geodynamic studies as well as for geothermal energy solutions heavily depend on rock thermal properties. Best practice for the determination of those parameters is the measurement of rock samples in the laboratory. Given the necessity to enlarge databases of subsurface rock parameters beyond drill core mea...

We present a regional 3D numerical crustal temperature model and analyze the present-day conductive thermal field of the Danish-German border region located in the North German Basin. A comprehensive analysis of borehole and well-log data on a regional scale is conducted to derive both the model parameterization with a spatial distribution of rock...

Information on both hydraulic and thermal conditions of the subsurface is fundamental for the planning and use of hydrothermal energy. This is paramount in particular for densely populated international border regions, where different subsurface applications may introduce conflicts of use and require reliable cross-border management and planning to...

In this study, equations are developed that predict for synthetic sedimentary rocks (clastics, carbonates and evapourates) thermal properties comprising thermal conductivity, specific heat capacity and thermal diffusivity. The rock groups are composed of mineral assemblages with variable contents of 15 major rock-forming minerals and porosities of...

Das INTERREG IVa Projekt GeoPower hatte zum Ziel, Planungsgrundlagen für die Nutzung hydrothermaler Energie für das nördliche Schleswig-Holstein und das südliche Jütland (Dänemark) zu schaffen. Projektpartner waren die Geologischen Dienste von Dänemark und Grönland (GEUS) und Schleswig Holstein (LLUR) sowie die geowissenschaftlichen Institute der U...

The bulk thermal conductivity (TC) of 26 rock samples representing felsic, intermediate and mafic granulites, from the Southern Granulite Province, India, is measured at dry and saturated conditions with the optical-scanning method. Thermal conductivity is also calculated from modal mineralogy (determined by XRD and EPMA), applying mixing models co...

Temperature-depth models developed in geothermal exploration are usually constrained by values of observed surface heat flow and the thermal conductivity of rocks. In several areas, in particular in the northern hemisphere, regional geothermal studies have shown that the subsurface temperatures and temperature gradients may be overprinted by the lo...

Most of the Danish area is characterized by deep sedimentary basins with a great potential for exploitation of geothermal energy. Geothermal reservoirs are present at various depths and temperatures. Currently, three geother-mal plants are operating producing warm water for district heating purposes. Information of subsurface temperature distributi...

Thermal modelling is used to examine the subsurface temperature field and geothermal conditions at various scales (e.g. sedimentary basins, deep crust) and in the framework of different problem settings (e.g. scientific or industrial use). In such models, knowledge of rock thermal properties is prerequisites for the parameterisation of boundary con...

Fuchs, S. (2015): Kommentar zu „Ableitung von Korngrößenverteilungen aus textbasierten petrografischen Bohrgutbeschreibungen“ von Michael Naumann, Anja Waldeck, Wolfgang Poßin, Carsten Schwarz & Joachim Fritz (Z. Dt. Ges. Geowiss., 165/2: 275?286). [Comment on “Deduction of grain size distributions based on petrographic borehole descriptions” by Mi...

In this study, the bulk thermal conductivity (TC) of 26 rock samples representing different types of granulite-facies rocks, i.e., felsic, intermediate and mafic granulites, from the Southern Granulite Province, India, is measured at dry and saturated conditions with the optical-scanning method. Thermal conductivity is also calculated from modal mi...

Ziel des Projektes GeoPower ist es, verbesserte geologische Planungsgrundlagen für die Nutzung geothermischer Energie in der INTERREG-Region Südjütland - Schleswig zu erstellen und öffentlich verfügbar zu machen. Die effektivste Nutzung der Erdwärme erfolgt hydrothermal, d.h. durch die Förderung von heißem Tiefenwasser. Geologische Voraussetzung is...

Information of subsurface temperature distribution in the Danish area originates from direct measurements in boreholes and from indirect theoretical modelling. “Point observations” of varying quality are available as industrially measured “Bottom Hole Temperatures” from deep exploration boreholes, and accurate continuous equilibrium temperature log...

Die Erstellung eines hydrogeologischen Models ausschließlich auf Basis von Bohrungsinformationen ist ein gleichermaßen häufig anzutreffende, wie auch besondere Herausforderung hinsichtlich der hydraulischen Parametrisierung der Modelschichten (i.e. bei fehlenden hydraulischen Testdaten). Am Beispiel des Naturschutzgebietes „Heiliges Meer“, welches...

The calculation of heat-flow density in boreholes requires reliable values for the change of temperature and rock thermal conductivity with depth. As rock samples for laboratory measurements of thermal conductivity (TC) are usually rare geophysical well logs are used alternatively to determine TC. A common procedure in the latter approach is the us...

Temperature-depth distributions are pivotal in subsurface studies in academia as well as in georesources applications. In this regard, high-resolution temperature profiles, logged under equilibrium thermal borehole conditions, are the ultimate measure. However there are circumstances in which these measurements are not available or only measured to...

Data on rock thermal conductivity (TC) are important for the quantification of the subsurface temperature regime and for the determination of heat flow. If drill core is not retrieved from boreholes and thus no laboratory measurement of TC can be made, other methods are desired to determine TC. One of these methods is the prediction of TC from well...

URN: urn:nbn:de:kobv:517-opus-67801 URL: http://opus.kobv.de/ubp/volltexte/2013/6780/ In sedimentary basins, rock thermal conductivity can vary both laterally and vertically, thus altering the basin’s thermal structure locally and regionally. Knowledge of the thermal conductivity of geological formations and its spatial variations is essential, no...

Rock thermal conductivity (TC) is paramount for the determination of heat flow and the calculation of temperature profiles. Due to the scarcity of drill cores compared to the availability of petrophysical well logs, methods are desired to indirectly predict TC in sedimentary basins. Most of the well-log-based approaches published require informatio...

This study predicts the subsurface temperature distribution of Germany’s capital Berlin. For this purpose, a data-based lithosphere-scale 3D structural model is developed incorporating 21 individual geological units. This model shows a horizontal grid resolution of (500 × 500) m and provides the geometric base for two different approaches of 3D the...

The thermal conductivity (TC) of a rock is, in collaboration with the temperature gradient, the basic parameter to determine the heat flow from the Earth interior. Moreover, it forms the input into models targeted on temperature prognoses for geothermal reservoirs at those depths not yet reached by boreholes. Thus, rock TC is paramount in geotherma...

To characterize the temperature regime in a sedimentary basin, knowledge of the rock thermal conductivity (TC) is vital. This also pertains to temperature prognosis for geothermal target reservoirs based on modelling, which in turn requires an assignment of TC values to model units. Those model units can consist of single lithotypes but are mostly...

In the light of an aspired reduction of CO2 emissions for Germany’s capital Berlin, one possible alternative for meeting the city’s growing energy demands lies in deep geothermal energy. To minimise exploration risks, a profound knowledge about the subsurface temperature distribution is indispensable. We present a 3D structural model that is used f...

In order to show the impacts of natural internal fault zones and well design on geothermal energy production, two main deep geothermal reservoir sites in Germany, Groß Schönebeck (GrSk) and Berlin Tempelhof which are part of the North German Basin (NGB) are investigated. Groß Schönebeck is located at about 40km away from the Berlin centre whereas B...

Different numerical models can be deployed to calculate the matrix thermal conductivity of a rock from the bulk thermal conductivity (BTC), if the effective porosity of the rock is known. Vice versa, using these parameters, the BTC can be determined for saturation fluids of different thermal conductivity (TC). In this paper, the goodness-of-fit bet...

Die geothermische Wärme des Tiefengesteins stellt ein großes Energiepotential dar, welches in Deutschland heute noch weitgehend unerschlossen ist. Dieser Beitrag behandelt Fragestellungen zur Erschließung dieses Potentials speziell im Nord-Ostdeutschen Becken. In den Gesteinporen der Tiefengesteine dieses Gebiets liegt heißes Thermalwasser vor, des...

Original research article: Matthes et al. (2012) http://link.springer.com/article/10.1007/s00767-012-0191-3 My comment: Fuchs et al. (2013) http://link.springer.com/article/10.1007%2Fs00767-012-0216-y Response to comment: Vienken et al. (2013) http://link.springer.com/article/10.1007/s00767-012-0215-z