ERE4.3 | Understanding the influence of lithospheric, crustal and sedimentary architecture on resource distribution
Understanding the influence of lithospheric, crustal and sedimentary architecture on resource distribution
Convener: Megan HoldtECSECS | Co-conveners: Sabin ZahirovicECSECS, Philip Ball
Orals
| Thu, 18 Apr, 08:30–10:15 (CEST)
 
Room 0.16
Posters on site
| Attendance Thu, 18 Apr, 10:45–12:30 (CEST) | Display Thu, 18 Apr, 08:30–12:30
 
Hall X4
Posters virtual
| Attendance Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
 
vHall X4
Orals |
Thu, 08:30
Thu, 10:45
Thu, 14:00
The transition to net-zero carbon emissions has necessitated a greater focus on energy critical minerals/metals, increased investment in renewable energy (e.g., geothermal, wind, solar), and intensified the focus on technology that can decarbonise industrial processes (e.g., carbon capture and storage, hydrogen). As momentum behind the renewable energy transition builds, it has never been more important to understand the first-order processes that control the distribution of resources on Earth. Resources that are critical to the energy transition include (but are not limited to) base metals (e.g., copper, lead, nickel), precious metals (e.g., gold, silver), rare earth elements and heat flow (e.g., for geothermal energy). In addition, understanding the architecture of sedimentary basins will be important for CCS. This session will explore how large-scale lithospheric, crustal and sedimentary processes influence the formation and present-day distribution of a given resource. By extension, this session will consider how we can enhance our understanding of these processes to improve predictions of resource distribution on a range of scales (i.e., global, regional, prospect scale).

Understanding the spatio-temporal formation of resources and how this influences their present-day distribution relies on the analysis and integration of multiple datasets and methods. We welcome studies that are multidisciplinary in nature, including the incorporation of observational data, numerical models, analogue studies, machine learning approaches and experimental methods. This session will provide an opportunity for attendees to learn from a range of disciplines and methods.

Orals: Thu, 18 Apr | Room 0.16

Chairpersons: Megan Holdt, Sabin Zahirovic, Philip Ball
08:30–08:50
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EGU24-22511
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solicited
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On-site presentation
Karol Czarnota and Exploring for the Future Team

The world is turning to the mining sector to resource the Net Zero transition and meet sustainable development goals. It is generally agreed that global inventories of critical minerals, strategic materials, natural hydrogen, and carbon sequestration sites are insufficient to meet forecast demand thereby necessitating new discovery and development. At the same time exploration success rates are declining across the world as resources become harder to discover and develop. These factors are compounded by the long average lead time from discovery to resource extraction, making the imperative to act now to ensure a sustainable resource pipeline. To reverse this worrying trend Australia has invested heavily into precompetitive geoscience aimed at characterising the geological, geochemical, and geophysical architecture of Australia from the surface to the mantle and across scales from which new insights into the spatiotemporal controls on resource distribution are emerging. Uptake of this information by Australia’s entrepreneurial exploration sector has led to the highest exploration success rate in the world. Here, we will review the value of precompetitive geoscience in Australia within a global context and showcase results arising from the Exploring for the Future program, Australia’s flagship investment in precompetitive geoscience of $225 m over the last eight years.  Specifically, we will highlight new insights into processes controlling the spatiotemporal distribution of sediment and crystalline basement-hosted mineral systems arising from assessments of the predictive power of new national datasets (e.g., passive seismic, magnetotelluric, airborne electromagnetic and isotopic maps). We will conclude with how these insights can be integrated across scale within a systems framework to test the resource potential of frontier region for metals as well as hydrogen and carbon capture and storage.

How to cite: Czarnota, K. and Team, E. F. T. F.: Exploring for the Future – precompetitive geoscience insight for resource discovery and development, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22511, https://doi.org/10.5194/egusphere-egu24-22511, 2024.

Heat Flow / Geothermal Energy
08:50–09:00
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EGU24-15177
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On-site presentation
Sven Fuchs, Ben Norden, Florian Neumann, Elif Balkan-Pazvantoğlu, Samah Elbarbary, Alexej Petrunin, and Global Heat Flow Data Assessment Group

Recently, the International Heat Flow Commission (IHFC), the Task Force VIII of the International Lithosphere Program (ILP) and a global network of geoscientists have jointly developed new standards for the structure and the quality evaluation of heat flow-density data. Heat-flow data are important for understanding the temperature field at shallow depths to the lithospheric scale and thus are fundamental for geodynamic and tectonic processes as well as for geoenergy applications, like geothermal utilizations. It often builds an essential parameter for analytical or numerical models of subsurface thermal models. Since 2021, the Global Heat Flow Database is undergoing an intensive collaborative assessment considering the new defined standards. The new quality scheme, for the first time, will allow a joint classification of data in terms of (i) numerical uncertainty, (ii) methodological evaluation, and (iii) overriding or perturbing effects. On the example of the Global Heat Flow Database Release 2024, we present for a regional example how the assessment changes the data density and detail of information stored and how the new quality standards effect regional heat flow statistics.

How to cite: Fuchs, S., Norden, B., Neumann, F., Balkan-Pazvantoğlu, E., Elbarbary, S., Petrunin, A., and Heat Flow Data Assessment Group, G.: Quality makes a difference: a preliminary update of the global continental heat flow dataset, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15177, https://doi.org/10.5194/egusphere-egu24-15177, 2024.

09:00–09:10
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EGU24-12843
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ECS
|
On-site presentation
Carlos Clemente-Gómez, Javier Fullea, Sergei Lebedev, Megan Holdt, and Helen Doran

Evaluating the geothermal potential of Africa requires a detailed understanding of its crustal and lithospheric structure. A coherent characterization of the geothermal gradient near the surface implies a bottom to top heat flow approach where knowledge of the thermal thickness of the lithosphere, the depth of the crust-mantle boundary, and crustal lithology (thermal conductivity and radiogenic heat production among other things) are essential. Unfortunately, direct measurements of subsurface temperature and local geophysical studies are scarce in most parts of Africa. In this work we present new predicted surface heat flow and crustal subsurface temperature maps, and new crustal structure models in Africa. The new models are obtained from a lithospheric integrated inversion approach using state-of-the-art surface waveform tomography data together with surface heat flow and elevation, crustal p-wave velocity and sedimentary thickness from controlled source seismic data. The inversion is framed within an integrated geophysical-petrological setting where mantle seismic velocities and densities are computed thermodynamically as a function of the in-situ temperature, pressure and compositional conditions. Within the three-layered crystalline crust, we invert for various geophysical parameters linked through lithology using global petrophysical measurements. The results of this work will be integrated into Project InnerSpace’s open-source GeoMap platform (https://projectinnerspace.org/), which aims to accelerate the uptake of geothermal energy by improving our knowledge of the subsurface.

How to cite: Clemente-Gómez, C., Fullea, J., Lebedev, S., Holdt, M., and Doran, H.: Mapping Africa’s geothermal potential: new surface heat flow and crustal temperature models from integrated geophysical-petrological inversion of surface wave and other data, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12843, https://doi.org/10.5194/egusphere-egu24-12843, 2024.

09:10–09:20
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EGU24-14033
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On-site presentation
Play Fairway Analysis for Regional Screening of Multi-Resource Potential in Sedimentary Basins: Evaluating Potential for Geothermal, Carbon Storage, and Lithium in Brines
(withdrawn)
Rand Gardner and Justin Birdwell
09:20–09:30
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EGU24-5899
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ECS
|
On-site presentation
Mohamed Sobh, Rodolfo Christiansen, Magued Al-Aghbary, and Gerald Gabriel

In geothermal resource assessment, terrestrial heat flow is a crucial metric, providing key insights into lithospheric thermal states and energy balance, with significant implications for geology, geophysics, and geodynamics. This study focuses on modeling geothermal heat flow (GHF) in Germany, where direct borehole temperature gradient data is limited, i.e. only 595 unevenly distributed published heat flow points exist.

To address this data scarcity, our approach utilizes indirect methodologies for GHF estimation. We integrate various geophysical and geological datasets, including gravity, magnetics, upper mantle velocity structure, topography, crustal and lithospheric thickness, fault distribution, proximity to volcanoes, and compositional data. This multi-faceted approach allows us to overcome the spatial constraints inherent in single-data reliance and more accurately reconstruct measured heat flow, e.g. in comparison to classical curie depth estimations.

Given the complexities in direct geophysical and geological data representation, our project utilizes a probabilistic, multi-geophysical inversion method. This not only enhances our understanding of Germany's geothermal potential but also allows for a detailed quantification of uncertainties.

We have developed a new heat flow map with a high resolution. This map more accurately and effectively illustrates the terrestrial heat flow distribution in the study area, providing a more detailed depiction than previous interpolation results. Our preliminary results have successfully identified high heat flow zones in regions such as the Rhenish Massif, Molasse Basin, and Upper Rhine Graben.

How to cite: Sobh, M., Christiansen, R., Al-Aghbary, M., and Gabriel, G.: Geothermal Heat Flow Mapping of Germany: Multi-Geophysical and Geological Data Inversion and Associated Uncertainties, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5899, https://doi.org/10.5194/egusphere-egu24-5899, 2024.

Critical Minerals / Metals
09:30–09:40
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EGU24-4835
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ECS
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Highlight
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On-site presentation
Ben Mather, Dietmar Müller, Christopher Alfonso, Nicky Wright, and Maria Seton

The oceanic seafloor is scarred by fracture zones, seamounts, and large igneous provinces (LIPs) which record tectonic deformation and plume impingement through deep time. The subduction of these seafloor anomalies has been speculated to localise slab tearing, enrich the mantle wedge in volatile elements, or trigger flat slab subduction. However, the association between these subducting seafloor anomalies and the emplacement of mineral deposits in the overriding plate is poorly understood. Using a tectonic plate reconstruction of the last 170 million years paired with a machine learning model trained on the location and age of known porphyry copper deposits, we find that the subduction of seafloor anomalies is highly predictive of mineral emplacement, particularly along the American Cordillera. The subduction of fracture zones and seamounts are consistently within the top 10 highest ranked features after the crustal thickness of the overriding plate and the plate convergence velocity. We propose that fracture zones, seamounts, and LIPs have higher degrees of hydrothermal alternation and serpentinization compared to regular seafloor which oxygenates the sub-arc mantle upon their subduction, leading to more fertile conditions for porphyry copper emplacement in the overriding plate. These findings have significant implications for the discovery of new porphyry copper deposits to power the renewable energy transition.

How to cite: Mather, B., Müller, D., Alfonso, C., Wright, N., and Seton, M.: Subducting seafloor anomalies promote porphyry copper emplacement, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4835, https://doi.org/10.5194/egusphere-egu24-4835, 2024.

09:40–09:50
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EGU24-6806
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On-site presentation
Stephen Foley, Isra Ezad, and Marco Fiorentini

As many critical metals are initially locked up in the volatile-bearing mantle, the first critical stage to any mineralizing process requires their liberation by partial melting of the mantle source, followed by the onset of an effective upward transport mechanism into the overlying crust. The initial melts of volatile-bearing mantle lithologies are incipient melts rich in volatile and incompatible components, which are effective transport agents at low mantle temperatures. This means that understanding the formation, composition, and migration of these melts is crucial to constraining metal transport in the mantle.

The incipient melts of peridotite usually solidify in the mantle to form dykes rich in hydrous minerals such as amphibole and mica. These assemblages commonly also contan abundant clinopyroxene and are known as “hydrous pyroxenites”, and may also contain several other accessory phases including apatite, ilmenite, and rutile.  We have recently gained abundant experimental information on the melting conditions and compositions of these hydrous pyroxenites, which can be viewed as second-stage melts. Although volumetrically minor in the lithosphere as a whole, these hydrous pyroxenites all produce melts at lower temperatures than peridotite, rapidly exhausting hydrous minerals such as amphibole, which have been discovered to host large concentrations of critical metals  [1].

Our results for trace element analyses of melts and residual minerals indicate that hydrous minerals such as phlogopite, amphiboles and apatite all have high partition coefficients for Ni (3-20) and other transition elements, meaning that the formation of hydrous pyroxenites during first-stage melting processes may lead to the formation of important repositories for Ni in the mantle sources of igneous rocks. The contribution of hydrous pyroxenites to the metal endowment of mantle melts may have been underestimated or overlooked in the past [1] due to the traditional association of magmatic Ni-sulfide ore deposits with basaltic to komatiitic rocks that originate by partial melting of uniform four-phase peridotite. The lower melting temperatures of hydrous pyroxenites (≈300˚C less than dry peridotite) also means that the generation of magmatic ore deposits may not require a major thermal perturbation such as a plume. Hydrous pyroxenites are commonly associated with continental regions, where their melting may be accentuated by erosion by edge-driven convection [2] or lateral advection of solids [3] at craton edges, thus explaining the association of both volatile-rich magmatism [4] and metal deposits [5] with craton edges. Thus, predictive exploration models should consider domains of the lithospheric mantle where hydrous pyroxenites may be localised and concentrated, as they may have been episodically melted throughout the long-lived geological evolution of cratonic blocks.

[1] Ezad IS et al. (2024) Mineralium Deposita. doi: 10.1007/s00126-023-01238.

[2] Davies DR and Rawlinson N (2014) Geology 42, 1031-1034.

[3] Muirhead JD et al. (2020) Nature 582, 67-72.

[4] Foley SF and Fischer TP (2017) Nature Geoscience 10, 897-902.

[5] Hoggard MJ et al. (2020) Nature Geoscience 13, 504-510.

How to cite: Foley, S., Ezad, I., and Fiorentini, M.: Metal endowment at craton edges controlled by amphibole-rich pyroxenites dykes and incipient melts in the mantle, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6806, https://doi.org/10.5194/egusphere-egu24-6806, 2024.

Natural Hydrogen
09:50–10:00
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EGU24-7867
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ECS
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On-site presentation
Frank Zwaan, Sascha Brune, Anne Glerum, Dylan A. Vasey, John Naliboff, Gianreto Manatschal, and Eric C. Gaucher

Naturally occurring hydrogen gas (H2) represents a potentially major source of clean energy. It has been relatively overlooked so far but has gained more attention recently. The most promising mechanism for large-scale generation of such natural H2 is the serpentinization of mantle material as it reacts with water while it is brought into the “serpentinization window” (i.e., T = 200-350˚C) during mantle exhumation. We study such serpentinization-related natural H2 generation during rifting and subsequent rift inversion by means of numerical geodynamic models. In these numerical models we trace how, when, and where mantle material enters the serpentinization window, as well as when active, large-scale faults penetrate exhumed mantle bodies allowing for water circulation and serpentinization to occur.

Although serpentinization-related natural H2 generation is a phenomenon best known from magma-poor rifted margins and slow spreading ridges, we find that volumes of natural H2 generated during inversion may be up to 20 times higher than during rifting, due to the colder thermal regime in rift-inversion orogenic environments. Moreover, suitable reservoirs and seals required for natural H2 accumulation are readily available in rift-inversion orogens, whereas they may not be present when serpentinization occurs in rift or drift settings. Our model results thus provide a first-order motivation to turn to rift-inversion orogens, rather than rifts and rifted margins, for natural H2 exploration. These model-derived insights are supported by indications of natural H2 generation in rift-inversion orogens such as the Western Alps, Pyrenees, and Caucasus.

How to cite: Zwaan, F., Brune, S., Glerum, A., Vasey, D. A., Naliboff, J., Manatschal, G., and Gaucher, E. C.: Rift-inversion orogens are the place to be for natural hydrogen gas (H2) exploration, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7867, https://doi.org/10.5194/egusphere-egu24-7867, 2024.

10:00–10:10
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EGU24-4264
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ECS
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On-site presentation
Investigation of natural hydrogen and helium in the Bohai Bay Basin, China: insights from Earth's spheres interactions
(withdrawn)
Yongbo Wei and Quanyou Liu
10:10–10:15

Posters on site: Thu, 18 Apr, 10:45–12:30 | Hall X4

Display time: Thu, 18 Apr 08:30–Thu, 18 Apr 12:30
Chairpersons: Megan Holdt, Sabin Zahirovic, Philip Ball
Heat Flow / Geothermal Energy
X4.180
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EGU24-16952
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Highlight
Florian Neumann, Sven Fuchs, Ben Norden, Elif Balkan-Pazvantoğlu, Alexej Petrunin, Samah Elbarbary, Samuel Jennings, Kirsten Elger, Simone Frenzel, Nikolas Ott, Stephan Maes, and Global Heat Flow Data Assessment Group

Since its establishment in 1963, the International Heat Flow Commission (IHFC) has fostering and curating the Global Heat Flow Database (GHFDB). The dynamic nature of techniques and methodologies used in heat-flow density determination has necessitated regular updates to the database. Despite its widespread utility, the GHFDB faces challenges arising from variations in measurement techniques and data quality. Ongoing efforts are dedicated to overcoming these challenges, aiming to elevate the database's accuracy and reliability, thus solidifying its value within the scientific community. Multiple iterations of the GHFDB exist, primarily focused on characterizing the quality of individual heat-flow data points. However, the establishment of a new, authenticated GHFDB demanded the development of a fresh reporting standards for heat-flow data submitted to the IHFC. This new framework, derived from a collaborative global initiative, incorporates 62 metadata fields. This comprehensive approach became imperative due to the escalating volume of data and the diverse methodologies employed, necessitating a standardized scheme to evaluate the quality of heat-flow density determinations consistently. This update provides insights into the community-driven initiative initiated in 2021, targeting the reassessment of approximately 1,414 publications containing 73,033 global heat-flow data points. A noteworthy aspect of this initiative is the introduction of a novel quality scheme, unifying three independent criteria into a combined score. This score encompasses quantified uncertainty, methodological quality, and the status of overruling effects. The integration of these criteria facilitates a swift comparison of heat-flow data, instantly revealing any missing data or inadequately documented information. The introduction of this quality scheme empowers users to efficiently select reliable heat-flow values tailored to their specific research purposes.

How to cite: Neumann, F., Fuchs, S., Norden, B., Balkan-Pazvantoğlu, E., Petrunin, A., Elbarbary, S., Jennings, S., Elger, K., Frenzel, S., Ott, N., Maes, S., and Data Assessment Group, G. H. F.: The heat flow data assessment project: Transformation of the global heat flow database, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16952, https://doi.org/10.5194/egusphere-egu24-16952, 2024.

X4.181
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EGU24-16175
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ECS
Elif Balkan-Pazvantoglu, Florian Neumann, Ben Norden, and Sven Fuchs

Terrestrial heat-flow determinations are crucial for understanding the thermal structure of the lithosphere. This study presents the results of a revision of the heat flow database in Türkiye contributing to the Global Heat Flow Data Assessment Project conducted by the International Heat Flow Commission (IHFC). The database includes 750 heat flow determinations reported in Türkiye between 1991 and 2023, and are reassessed according to the new IHFC specific structure documented by Fuchs et al. (2023). The data are gathered from the original literature and examined to ensure complete documentation of relevant metadata. The quality score is assigned based on the uncertainty, methodology and environmental disturbances. The new national wide database shows that heat-flow determinations are predominantly distributed in the western part of the country. However, the eastern part of the country has been poorly investigated to date. Despite numerous exploration-based studies conducted in the region concerning its substantial geothermal potential, a noteworthy portion of thermal data remains archived and is not accessible. The study reveals a significant demand for additional heat flow determinations to allow the drawing of a substantially revised and robust heat-flow map. However, the ongoing update of the Türkiye Heat Flow Database already allows a more transparent identification of areas with thermal anomalies.

How to cite: Balkan-Pazvantoglu, E., Neumann, F., Norden, B., and Fuchs, S.: Assessment of the Türkiye Heat Flow Database 2023, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16175, https://doi.org/10.5194/egusphere-egu24-16175, 2024.

X4.182
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EGU24-10134
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ECS
Lucas Medeiros Bofill, Gerhard Schäfer, Guilherme Bozetti, Mathieu Schuster, Jean-François Ghienne, Philippe Ackerer, Claiton Scherer, Ezequiel Souza, and Garibaldi Armelenti

Sedimentary processes govern fluid-flow heterogeneities in porous media in several scales, therefore, their understanding is a common practice in the petroleum industry. However, hydrogeologists have lagged behind when it comes to discretising porous sedimentary aquifers in flow, heat and transport models. At the Upper Rhine Graben, in Eastern France, the Lower Triassic Buntsandstein Group serves as an important reservoir for groundwater and lithium-rich geothermal brines. The main objective of this study is to assess the architecture of the Lower Grès Vosgien Formation (LGV), Middle Buntsandstein, and how sedimentological processes, at different scales, generate significant permeability heterogeneities. It is implemented a high-resolution sedimentological characterisation, through vertical profile descriptions, digital outcrop model, and petrographic analysis. Subsequently, permeability measurements are coupled with sedimentological data, to identify different scales of sedimentary controls on permeability distribution. Finally, a realistic 2D hydrostratigraphic conceptual model is generated as a reference, allowing the evaluation of how different scenarios of heterogeneity simplification impact fluid-flow modelling, concerning particle residence time, macro-dispersivity, and upscaled anisotropy.

Results indicate that 93% of the LGV is composed of sandstones deposited by a braided fluvial system, with evidence suggesting that discharge variability was a main depositional controlling factor of sedimentary facies and heterogeneity distribution. The LGV stacking pattern reveals periods when fluvial processes were absent, and aeolian processes dominated sediment transport and deposition, comprising 7% of the total LGV thickness. The aeolian deposits record signs of persistent water in the system, either due to water table rise, or ephemeral floods, primarily contributing to the sedimentary facies association with the lowest permeabilities of the LGV, exceeding 3 orders of magnitude lower than the fluvial deposits. Despite representing only 7% of the LGV total thickness, the aeolian deposits exhibit lateral extensions that extrapolate outcrop scales (hundreds of metres), representing significant vertical flow baffle zones.

Fluid-flow simulations demonstrate that model simplifications, whether through assigning deterministic permeability values (mean), or stochastically distributing permeabilities, unconstrained by realistic sedimentary architectures, have a direct impact on macro-dispersivity (both vertical and horizontal), vertical mean residence time, and upscaled anisotropy results. Nevertheless, the results for horizontal mean residence time show no significant effect when simplifying the observed sandstone heterogeneities.

How to cite: Medeiros Bofill, L., Schäfer, G., Bozetti, G., Schuster, M., Ghienne, J.-F., Ackerer, P., Scherer, C., Souza, E., and Armelenti, G.: Sedimentological control on permeability heterogeneity, and its effects in fluid-flow modelling: a case study of the Middle Buntsandstein sandstones, Upper Rhine Graben, Eastern France, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10134, https://doi.org/10.5194/egusphere-egu24-10134, 2024.

Critical Minerals / Metals
X4.183
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EGU24-7869
Imma Palomeras, Puy Ayarza, Juan Gomez-Barreiro, David Martí, José Ramón Martínez-Catalán, Yolanda Sánchez-Sánchez, Kelvin Dos Santos, Mariano Yenes, Irene Pérez-Cáceres, Santos Barrios, Javier Élez, and Irene DeFelipe

During the late stages of the Variscan orogeny, generalized gravitational collapse with coeval magmatism took place in the Central Iberian Zone, in Iberia. This event is getting the attention of the scientific community due to its likely role in the generation of strategic mineral resources (i.e. Sn, W, Nb, Ta, Sc, Au, Sb). In this regard, to study how the Variscan orogenic architecture controls the generation of mineral deposits the GOLDFINGER project was born. As part of the project, the Martinamor gneissic dome (Salamanca), which presents several mineral deposits, was covered by 31 short-period (2 Hz) 3-component seismic stations. Through applying techniques of ambient noise seismic interferometry, we have constructed a 3D S-wave velocity model of the extensional dome, allowing us to extend in depth the geometry of igneous rocks, their host rocks, and some of the structures. Among the most relevant results, we have identified the depth configuration of a granitic body outcropping discontinuously east of the study area, and whose upper boundary has been interpreted as the extensional dome detachment level. This structure may have provided a pathway for mineralizing fluids. This work demonstrates that the seismic noise interferometry technique has sufficient resolution to interpret medium-scale structures and to discern different lithologies with moderately contrasted physical properties.

Funding: grant PID2020-117332GB-C21 funded by MCIN/ AEI /10.13039/501100011033; EIT-Raw Materials project 17024 (SIT4ME: Seismic Imaging Techniques for Mineral Exploration); SA084P20 from the JCyL government, and TED2021-130440B-I00 funded by MCIN/AEI/10.13039/501100011033 and European Union NextGenerationEU/PRTR.

How to cite: Palomeras, I., Ayarza, P., Gomez-Barreiro, J., Martí, D., Martínez-Catalán, J. R., Sánchez-Sánchez, Y., Dos Santos, K., Yenes, M., Pérez-Cáceres, I., Barrios, S., Élez, J., and DeFelipe, I.: Imagining the Deep Structure of a Mineralized Extensional Dome in the Variscan Central Iberian Zone (Spain) using Ambient Noise Seismic Data., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7869, https://doi.org/10.5194/egusphere-egu24-7869, 2024.

X4.184
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EGU24-11471
Paolo Nimis, Nasser Aminizadkovij, Christine Meyzen, Luca Toffolo, Irina Melekestseva, Omar Paccagnella, and Clifford Patten

Seafloor massive sulfide (MS) deposits on oceanic spreading centers have variable concentrations of base metals (mostly Cu, Zn), precious metals (Au, Ag), critical metals (Co, Ni), and other trace elements. The geological factors that control this geochemical variability are still a matter of debate. In particular, the role of the composition of substrate rocks (specifically mafic vs. ultramafic) has been variably considered to be decisive or subordinate. In a previous study (Toffolo et al., 2020, Earth Sci. Rev.), we have investigated these factors by means of robust principal component and factor analysis of chemical data for MS samples from mid-ocean ridges worldwide. We found that a large part of the observed variability is produced by a combination of three independent factors, interpreted to reflect (in order of importance): (1) the temperature of deposition, which controls the relative enrichments in (Cu, Se, Co) vs. (Pb, Sb, Zn, Ag), (2) the ridge spreading rate, which influences the oceanic basement structure and the rock-to-water ratios, leading to opposite behaviors of (Au, Ag) vs. Ni, and (3) zone refining. Unexpectedly, the composition of the substrate did not emerge as a statistically significant independent factor. An important limit of our previous investigation was that literature data were often incomplete, thus limiting the number of samples and of chemical elements for the multivariate statistical analysis. We have now addressed this problem by using statistical imputation techniques and by integrating the database with additional literature and in-house data for present-day deposits on mid-ocean ridges and ancient deposits in ophiolites from different settings (supra-subduction-zone, mid-ocean ridge, ocean-continent transition). As a result, undersampling of ultramafic-hosted deposits was significantly reduced and the number of elements was raised to 11, including Cu, Zn, Pb, Au, Ag, Co, Ni, Se, Sb, Mo and the previously excluded As. The integrated database essentially confirms our previous findings. In addition, deposits in supra-subduction-zone ophiolites show factor scores typical of high deposition temperatures and high rock-to-water ratios, consistent with their formation on infant-arc, slow-spreading centers. The potential influence of other local geological factors will be discussed.

How to cite: Nimis, P., Aminizadkovij, N., Meyzen, C., Toffolo, L., Melekestseva, I., Paccagnella, O., and Patten, C.: Multivariate statistical analysis of mafic- and ultramafic-hosted seafloor massive sulfides, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11471, https://doi.org/10.5194/egusphere-egu24-11471, 2024.

X4.185
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EGU24-9006
Taija Torvela, Rob Chapman, James Shaw, Georgian Manuc, and Lucia Savastano

The Caledonian-Appalachian Belt (CAB) hosts several economic and sub-economic polymetallic vein systems and is, therefore, an excellent natural laboratory to study the variations in the characteristics of ore deposit and the timing of their formation, within an orogenic belt. We present some of the preliminary outcomes of a large-scale study on the variability of the vein-hosted mineralisation within the CAB, covering c. 20 different polymetallic vein systems within the Grampian Terrane and its equivalents in Scotland, Northern Ireland, Ireland and Newfoundland.

The multi-disciplinary study combines structural data, age determinations, vein textural mapping and paragenetic interpretation, gold geochemical characterisation, and stable isotope data to show that although the occurrences show many superficial structural and mineralogical similarities, there are significant differences between the structural styles, mineralogy and timing of the mineralisation in different areas (see [1] and [2] for the first publications coming from this work). At least three, possibly four, distinct mineralisation stages are identified between Ordovician and Early Devonian, each associated with a characteristic structural style that can be linked to the overall tectonic evolution of the Grampian Terrane. The tectonic evolution of the orogen in time and space therefore greatly influenced both the timing and the style of mineralisation.

References:

[1] Shaw J, Torvela T, Cooper M, Leslie G, Chapman R (2022). A progressive model for the Cavancaw Au-Ag-Pb vein deposit, Northern Ireland, and implications to the metallogeny and evolution of the Grampian Terrane. J. Struct. Geol. 161, https://doi.org/10.1016/j.jsg.2022.104637.

[2] Chapman R., Torvela T, Savastano L (2023).  Insights into regional metallogeny from detailed compositional studies of alluvial gold: An example from the Loch Tay area, central Scotland. Minerals 13, doi.org/10.3390/min13020140.

How to cite: Torvela, T., Chapman, R., Shaw, J., Manuc, G., and Savastano, L.: Relationships between the tectonic evolution of an orogen and the formation of polymetallic vein deposits , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9006, https://doi.org/10.5194/egusphere-egu24-9006, 2024.

Sedimentary Basins
X4.186
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EGU24-8097
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ECS
Lithologic prediction of strata based on hierarchical Bayesian modeling: an example of Carboniferous strata in the northern Junggar Basin
(withdrawn after no-show)
Yujian Hou, Zhanxiang He, Fangda Song, Yibo Zhai, and Qiyun Jiang
X4.187
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EGU24-4824
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ECS
Shuai Hou and Youlu Jiang

There are two sets of petroliferous strata developed in the Huoshiling Formation volcano in the Longfengshan area of the Changling fault Depression. The oil and gas have the characteristics of "near source gas, far source oil rich", the abundance of oil and gas decreases from the depression zone to the western tectonic belt, and is enriched in the top and middle of volcanic rocks in longitudinal direction, and widely distributed along faults in plane. In this paper, the controlling factors of hydrocarbon distribution in volcanic rocks are discussed from the perspectives of source rock development condition, reservoir physical property and transport condition by means of seismic, well logging and geochemical data, cores and microsections observation, CT scanning and inclusion analysis. The results show that the oil and gas distribution in the volcanic rock mass in Longfengshan area is mainly affected by the following factors: the thermal evolution degree of the source rock controls the oil and gas phase distribution, and the source and reservoir configuration determines the oil and gas capture probability; The distribution characteristics of high-quality volcanic rock reservoir can control the distribution range of oil and gas, and the vertical development difference of primary, secondary dissolution and fracture high-quality reservoirs determines the vertical accumulation of oil and gas. The fault and unconformity control the migration of oil and gas from the depression zone to the slope zone and the western tectonic zone, and its transport performance and the micro-transport structure of internal fractures ultimately determine the location of oil and gas accumulation. The distribution of overlying layers in and above volcanic rocks, the type of reservoir-cap combination and the configuration of broken cap prevent the oil and gas loss and control the oil and gas enrichment horizon. Based on the differences of main controlling factors of hydrocarbon accumulation in volcanic rocks, the effective source rock thickness, volcanic reservoir physical properties, reservoir-cap combination characteristics and transport conditions are taken as indicators to evaluate the hydrocarbon charging capacity of volcanic rocks, and the measured values of the above factors are divided into several intervals. According to the distribution range of the evaluation index, each interval is evaluated. Finally, according to the calculation results of the established oil and gas charging capacity evaluation formula, the evaluation results have a good correspondence with the current oil and gas distribution, and the results have certain guiding significance for determining the direction of oil and gas exploration in the later period.

How to cite: Hou, S. and Jiang, Y.: Main controlling factors of volcanic oil and gas distribution and charging capacity evaluation of Huoshiling Formation in Longfengshan area, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4824, https://doi.org/10.5194/egusphere-egu24-4824, 2024.

X4.188
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EGU24-9047
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ECS
Controls of multi-stage strike-slip faults on migration and accumulation of hydrocarbon: Ordovician reservoirs in the north slope of Tazhong, Tarim Basin, China
(withdrawn after no-show)
Siqi Ouyang and Xiuxiang Lyu
Natural Hydrogen
X4.189
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EGU24-19882
Understanding Tectonic and Sedimentary Controls for the Reconstruction of the Hydrothermal History in Magma-poor Rifted Margins
(withdrawn after no-show)
Javier García-Pintado and Marta Pérez-Gussinyé
X4.190
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EGU24-7674
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ECS
Rodolfo Christiansen, Mohamed Sobh, and Gerald Gabriel

Natural hydrogen, emerging as a clean and abundant energy source, holds significant promise for advancing sustainable energy solutions. Its production offers a carbon-neutral alternative to fossil fuels, aligning with global efforts to mitigate climate change. This research focuses on developing a methodology to estimate the rates of natural hydrogen generation in serpentinization areas; in this case a local area in Eastern Morocco. It employs a multilevel approach that encompasses the modeling and analysis of the surface, near-surface, and deep components of the natural hydrogen system. At the surface level, potential hydrogen seeps are identified as semi-circular structures and surface faults are examined using high-resolution geophysical data. For the near-surface component or seal of the potential reservoir, which can extend thousands of meters deep, a full 3D geological model is constructed. The deep component, representing the source rock, is analyzed through the inversion of potential field data. These inversion results allow estimating the degree of serpentinization of the rocks, their volumes, and the affected surfaces. Subsequently, these volumes of rock are compared with temperature estimates to determine which part of the rock is capable of generating hydrogen. Laboratory-based hydrogen generation values from rock samples are then scaled up to the model, facilitating the calculation of hydrogen generation rates from the detected ultramafic rocks.

How to cite: Christiansen, R., Sobh, M., and Gabriel, G.: Assessing Natural Hydrogen Generation in Serpentinization Environments: A Workflow Based on a Comprehensive Case Study Analysis from the HyAfrica Project, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7674, https://doi.org/10.5194/egusphere-egu24-7674, 2024.

Posters virtual: Thu, 18 Apr, 14:00–15:45 | vHall X4

Display time: Thu, 18 Apr 08:30–Thu, 18 Apr 18:00
Chairpersons: Megan Holdt, Sabin Zahirovic, Philip Ball
vX4.43
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EGU24-2426
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ECS
KaiQi Sheng

Extensive lacustrine carbonate-rich shale intervals including upper fourth member (Es4s shale) and lower third member (Es3x shale) of the Paleogene Shahejie Formation have been deposited in the Boxing Sag, Dongying depression, Bohai Bay Basin, East China. These two representative shale members are considered to be good exploration prospects in the study area. In order to clarify the diagenetic process and exploration significance of sparry calcite in lacustrine calcareous shales, we take calcareous shale in Es4s to Es3x members in Boxing Sag as the research object, By means of thin section identification method, EDS line scan, Scanning Electron Microscopy, Fluid Inclusion Analysis, carbon and oxygen isotope and other methods, sparry calcite is classified, and then the genesis and diagenetic fluid of various types of sparry calcite are studied, so as to clarify the formation mechanism of sparry calcite, and finally discuss the influence of sparry calcite on reservoir. Finally, the influence of sparry calcite on the development of reservoir pores was discussed. The results show that the types of sparry calcite in the study area include granular calcite, porphyritic calcite and fibrous calcite, which are mainly caused by biological oxidation and thermal evolution of organic matter. Biogenic calcite has the characteristics of rich Mg and δ13C, and the organic matter makes the crystal more enriched with Fe and deficient δ13C. The formation of three kinds of sparry calcite has different effects on pore development, which is probably beneficial to improve reservoir physical properties.

How to cite: Sheng, K.: Early Diagenesis In Carbonate Sediments, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2426, https://doi.org/10.5194/egusphere-egu24-2426, 2024.

vX4.44
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EGU24-12704
Potential lithium enrichment above Hercynian migmatite terrains in Europe
(withdrawn)
Leo Kriegsman, Elisa da Costa, and Barbara Kunz