Mohamed Gouiza

Lower Carboniferous Limestone (LCL) is a promising geothermal target in Britain, but uncertainty in subsurface structure and permeability limits resource assessment. Here, we use the Welton area of the East Midlands, where legacy hydrocarbon exploration data provide detailed subsurface coverage, to investigate the controls on LCL geothermal prospectivity. We integrate 3D seismic reflection, well, gravity and aeromagnetic data with gravity forward and inverse modelling to characterise the geometry and structural evolution of the LCL. Seismic interpretation reveals a heterogeneous reservoir partitioned into a western rift-bounding fault corridor, an eastern relay system and a northern fault-intersection zone, together with fault-tip and segment-linkage structures. Seismic-stratigraphic relationships record late Carboniferous reactivation of this inherited extensional architecture, expressed by localised LCL doming and erosion, Namurian absence and onlap, and onlap within the lowermost Westphalian. These relationships indicate variable inversion and possible weathering or palaeo-karst development on uplifted LCL highs. Gravity and magnetic lineaments reproduce and extend seismic-scale structural trends, while source-depth estimates indicate that parts of the fault network were localised above deeper inherited fabrics. Gravity modelling shows that plausible LCL density variations alone cannot explain the observed gravity field, requiring deeper or unmodelled density heterogeneity. The integrated results define three conceptual structural geothermal plays: a fault-damage-zone play, a relay/linkage play and a fault-intersection play. These settings may favour secondary permeability through fracturing, augmented by inversion-related deformation and possible palaeokarst development, although present-day transmissivity remains unconstrained. This study demonstrates how legacy seismic and potential-field datasets can support geothermal targeting in structurally complex carbonate reservoirs.

Heat zoning frameworks emerging across Europe assess heat demand and network viability using surface-level indicators but lack subsurface geothermal resource data. Separately, geological assessments of urban geothermal potential are rarely connected to energy planning or stakeholder decision-making. This paper presents a multidisciplinary methodology which bridges these domains, combining geological modelling, geospatial energy analysis, GIS-based spatial integration, and stakeholder co-design through a decision theatre. The methodology translates probabilistic geological estimates into planning-compatible formats, overlays them with building stock, heat demand and development data to identify spatial alignments and mismatches, and tests integrated proposals through structured stakeholder engagement. We applied this integrated approach across three contrasting potential heat network zones in Leeds, UK: an established city centre with existing district heating, a greenfield development area, and a mixed existing settlement. In each case, the integrated methodology generated context-sensitive proposals which no single-domain analysis could provide. In the city centre, it revealed a viable geothermal resource beneath an incumbent network whose commercial model could not accommodate it. This led to proposals for new networks beyond the existing system. In the greenfield zone, overlaying subsurface potential with the development pipeline revealed a closing temporal window, with homes being consented above viable aquifers using incompatible heating systems. In the existing settlement, the methodology identified misclassified anchor loads that altered the viability assessment for network development. These findings demonstrate that integrating subsurface and surface data within planning processes reveals resource opportunities, development conflicts and implementation barriers invisible when geological assessment and energy planning are conducted independently. The integration logic is transferable to contexts where geological and surface-level planning data are available.

Heat network zoning has emerged as a key governance instrument for urban heat decarbonisation. However, its implementation requires integration with spatial planning systems and comprehensive assessment of available heat sources. This paper examines how vertical (cross-scale) and horizontal (cross-sector) governance misalignment shapes prospects for integrating geothermal resources into heat network zones. Through geological modelling, geospatial analysis of planning decisions and stakeholder engagement in Leeds, UK, we identify a pattern of dual exclusion, where open-loop geothermal capacity sufficient to meet over 90% of heat demand mostly falls outside statutorily designated heat network zones, whilst within zones, planning approvals for incompatible heating systems are creating carbon lock-in which rules out future network connection. We find that these outcomes are systematically produced by governance architecture which fragments decision-making across scales and sectors, where national heat zoning proceeds without subsurface resource data whilst lacking statutory weight in local spatial planning. We propose an integrated governance framework and three policy reforms linking heat network zoning, spatial planning and subsurface resource management to address resource exclusion and prevent carbon lock-in in urban heat decarbonisation programmes.

Heat zoning frameworks emerging across Europe assess heat demand and network viability using surface-level indicators but lack subsurface geothermal resource data. Separately, geological assessments of urban geothermal potential are rarely connected to energy planning or stakeholder decision-making. This paper presents a multidisciplinary methodology which bridges these domains, combining geological modelling, geospatial energy analysis, GIS-based spatial integration, and stakeholder co-design through a decision theatre. The methodology translates probabilistic geological estimates into planning-compatible formats, overlays them with building stock, heat demand and development data to identify spatial alignments and mismatches, and tests integrated proposals through structured stakeholder engagement. We applied this across three contrasting zones in Leeds, UK: an established city centre with existing district heating, a greenfield development area, and a mixed existing settlement. In each case, the integrated methodology generated context-sensitive proposals which no single-domain analysis could provide. In the city centre, it revealed a viable geothermal resource beneath an incumbent network whose commercial model could not accommodate it. This led to proposals for new networks beyond the existing system. In the greenfield zone, overlaying subsurface potential with the development pipeline revealed a closing temporal window, with homes being consented above viable aquifers using incompatible heating systems. In the existing settlement, the methodology identified misclassified anchor loads that altered the viability assessment for network development. These findings demonstrate that integrating subsurface and surface data within planning processes reveals resource opportunities, development conflicts and implementation barriers invisible when geological assessment and energy planning are conducted independently. The integration logic is transferable to contexts where geological and surface-level planning data are available.

As cities across the UK seek to decarbonise heat and achieve net-zero targets, shallow geothermal energy presents an underutilised yet promising resource. In this study, we evaluate the geothermal potential of the upper 1,000 m of the subsurface beneath Leeds, a major urban centre underlain by Carboniferous sandstone aquifers and abandoned coal mine workings. Using geological maps and legacy borehole data, we construct a 3D subsurface model to carry out a stochastic calculation of the volumetric Heat-in-Place (HIP). Four geothermal targets were assessed: the Elland Flags, Upper and Lower Millstone Grit formations, and flooded mine workings. Our results reveal a substantial median geothermal resource exceeding 1,833,333 GWh of thermal energy, with a total recoverable heat output of over 700 MW (>500,000 home equivalent). The Lower Millstone Grit was identified as the most significant reservoir due to its depth and elevated temperatures, while the shallower Elland Flags and mine water systems offer localised low-temperature potential suitable for near-surface heating schemes. Spatial mapping of HIP indicates favourable alignment between zones of high energy potential and areas of heat demand, supporting the integration of geothermal resources into future heat networks. Our work also highlights key geoscientific and regulatory barriers to deployment and outlines the data needed to reduce uncertainty and enable investment. Overall, this work demonstrates the strategic role of urban geothermal energy in supporting Leeds’ transition to a low-carbon heat system and offers a transferable methodology for application in other cities in the UK and beyond.

The Atlas fold and thrust belt extend from the Atlantic rifted margin of Morocco to Tunisia over a distance of 2500km. Before its inversion in the Cenozoic to the present, the Atlas system evolved initially as a rift basin that opened simultaneously with the Atlantic rift in the west and the Tethys in the north, during the upper Triassic-Jurassic period.The Western High Atlas is believed to be influenced by the Atlantic Ocean (also known as the Atlantic domain), where the Triassic to Early Jurassic strata are considered to be syn-rift, while the Middle Jurassic to Cretaceous deposits are labelled as post-rift. In contrast, the Marrakech High Atlas (MHA), Central High Atlas (CHA), Middle Atlas (MA), and the Eastern High Atlas (EHA) are assumed to be influenced by the Tethys Ocean (also known as Tethyan domain), where the Triassic to Jurassic sediments are considered to be syn-rift. This implies that the Mesozoic rifting along the Atlas was diachronous, making it difficult to determine the exact timing and kinematic of crustal stretching. Constraining the extensional phases in the Atlas system is crucial for understanding how the Atlas crust was stretched and thinned. Our work aims to quantify the magnitude and regional kinematic of stretching in the Atlas system using various methods, namely, thickness variation method, subsidence analysis and palinspatic reconstruction of 2D cross-sections.Our preliminary results indicate that the maximum stretching factor (beta factor) in the Atlas is β = 1.25; and that crustal thinning did not exceed 20%, based on tectonic subsidence analysis. While the palinspatic restoration suggest that the Moroccan Atlas system underwent approximately a uniform stretching with β = 1.11 in EHA (Midelt-Errachidia area), β = 1.08 in CHA (Imilchil area), and β = 1.12 in the East Marrakech High Atlas (EMHA: Demnat area). These values indicate that the Moroccan Atlas crustal thickness has been thinned by 9% in EHA, 8% in CHA, and 11% in EMHA. In addition, the geological context of the High and Middle Atlas regions, where the estimated shortening is reported to be less than 20%, the stretching factor (β) was calculated based on the crust thickness. The initial crustal thickness (IC) of the Meseta block, which constitutes one of the Atlasic rift shoulders, considered an undeformed area, served as a reference. Accounting for the observed shortening, the final crustal thickness was deduced by subtracting the reported shortening value representing 7.8 km from the observed crustal thickness (39 km), resulting in a β value of 1.25, which is consistent with the result obtained from the subsidence analysis.Keywords: Atlas system, extension, stretching factor, Thinning factor,

Artificial intelligence (AI), mostly in the form of chatbots based on large language models (LLM), now permeates society at large, whether for positive, negative, trivial or even toxic purposes. AI is also increasingly used in various aspects of scientific research, from large-scale data analysis to manuscript preparation. At Tektonika, the Executive Editor’s group and the Core members engaged in discussions while drafting our guidelines on the use of AI. These exchanges revealed a divide between those who see AI as bringing significant positive contributions and those who are more skeptical, fearing a loss of expertise and a decline in cognitive skills. Some of the key questions that emerged about the benefits of AI are: Do we accept or even encourage the use of AI? At what stages of the research process? What is acceptable or not for manuscript preparation or reviewing? Conversely, several challenges were also identified prompting questions such as: do we just see the use of AI as inevitable, placing us on a damage-limitation exercise? Are we concerned about laziness in research and writing, about false information? Are we able to discern whether or not a manuscript is AI-generated, partially or totally?

Rifting and continental break-up are major research topics within geosciences, and a thorough understanding of the processes involved as well as of the associated natural hazards and natural resources is of great importance to both science and society. As a result, a large body of knowledge is available in the literature, with most of this previous research being focused on tectonic and geodynamic processes and their links to the evolution of rift systems. We believe that the key task for researchers is to make our knowledge of rift systems available and applicable to face current and future societal challenges. In particular, we should embrace a system analysis approach and aim to apply our knowledge to better understand the links between rift processes, natural hazards, and the geo-resources that are of critical importance to realise the energy transition and a sustainable future. The aim of this paper is therefore to provide a first-order framework for such an approach by providing an up-to-date summary of rifting processes, hazards, and geo-resources, followed by an assessment of future challenges and opportunities for research. We address the varied terminology used to characterise rifting in the scientific literature, followed by a description of rifting processes with a focus on the impact of (1) rheology and stain rates, (2) inheritance in three dimensions, (3) magmatism, and (4) surface processes. Subsequently, we describe the considerable natural hazards that occur in rift settings, which are linked to (1) seismicity, (2) magmatism, and (3) mass wasting, and provide some insights into how the impacts of these hazards can be mitigated. Moreover, we classify and describe the geo-resources occurring in rift environments as (1) non-energy resources, (2) geo-energy resources, (3) water and soils, and (4) opportunities for geological storage. Finally, we discuss the main challenges for the future linked to the aforementioned themes and identify numerous opportunities for follow-up research and knowledge application. In particular, we see great potential in systematic knowledge transfer and collaboration between researchers, industry partners, and government bodies, which may be the key to future successes and advancements.

Rifting and continental break-up is a key research topic within geosciences, and a thorough understanding of the processes involved, as well as of the associated natural hazard and natural resources is of great importance to both science and society. As a result, a large body of knowledge is available in the literature, yet most of previous research focuses on tectonic and geodynamic processes and their links to the evolution of rift systems. However, we believe that the key challenge for researchers is to make our knowledge of rift systems available and applicable to face new societal challenges. In particular, we should embrace a system analysis approach, and aim to apply our knowledge to better understand the links between rift processes, natural hazards, and the geo-resources that are of critical importance to realize the energy transition and a sustainable future. The aim of this paper is therefore to provide a first-order framework for such an approach, by providing an up-to-date summary of rifting processes, hazards, and geo-resources, followed by an assessment of future challenges and opportunities for research. We address the varied terminology used to characterise rifting in the scientific literature, followed by a description of rifting processes with a focus on the impact of (1) rheology and stain rates, (2) inheritance in three dimensions, (3) magmatism, and (4) surface processes. Subsequently, we address the considerable natural hazards and risks that occur in rift settings, which are linked to (I) seismicity, (II) magmatism, and (III) mass wasting, and provide some insights in how the impacts of these hazards can be mitigated. Moreover, we classify and describe the geo-resources occurring in rift environments as (a) non-energy resources, (b) geo-energy resources, (c) water and soils, and (d) opportunities for geological storage. Finally, we discuss the key challenges for the future linked to the aforementioned themes, and identify numerous opportunities for follow-up research and knowledge application. In particular, we see great potential in systematic knowledge transfer and collaboration between researchers, industry partners and government bodies, which may be the key to future successes and advancements.

Rifting and continental break-up is a key research topic within geosciences, and a thorough understanding of the processes involved, as well as of the associated natural hazard and natural resources is of great importance to both science and society. As a result, a large body of knowledge is available in the literature, yet most of previous research focuses on tectonic and geodynamic processes and their links to the evolution of rift systems. However, we believe that the key challenge for researchers is to make our knowledge of rift systems available and applicable to face new societal challenges. In particular, we should embrace a system analysis approach, and aim to apply our knowledge to better understand the links between rift processes, natural hazards, and the geo-resources that are of critical importance to realize the energy transition and a sustainable future. The aim of this paper is therefore to provide a first-order framework for such an approach, by providing an up-to-date summary of rifting processes, hazards, and geo-resources, followed by an assessment of future challenges and opportunities for research. We address the varied terminology used to characterise rifting in the scientific literature, followed by a description of rifting processes with a focus on the impact of (1) rheology and stain rates, (2) inheritance in three dimensions, (3) magmatism, and (4) surface processes. Subsequently, we address the considerable natural hazards and risks that occur in rift settings, which are linked to (I) seismicity, (II) magmatism, and (III) mass wasting, and provide some insights in how the impacts of these hazards can be mitigated. Moreover, we classify and describe the geo-resources occurring in rift environments as (a) non-energy resources, (b) geo-energy resources, (c) water and soils, and (d) opportunities for geological storage. Finally, we discuss the key challenges for the future linked to the aforementioned themes, and identify numerous opportunities for follow-up research and knowledge application. In particular, we see great potential in systematic knowledge transfer and collaboration between researchers, industry partners and government bodies, which may be the key to future successes and advancements.