Carbonate rocks can control how strong the Earth’s crust is in places. They are often described in simple terms as calcite or dolomite, but they are more complicated. At the atomistic level different amounts of elements, like magnesium and calcium, are incorporated at different temperatures and at the microscopic level carbonates can have different internal structures. We review 50 years of experimental data to provide equations that can describe the strength of most kinds of carbonates.

We have studied the stress conditions at the Decatur CO₂ storage site that would induce the observed microseismicity. Initial estimates suggested that faults required higher pressure to slip than the injection pressure, but refining pressure and friction assumptions led to more realistic scenarios. Our study highlights the importance of accurate stress state measurements and high-quality data to better predict reservoir response to injection and improve the safety and reliability of CO₂ storage.

A novel modeling approach of crustal seismics is developed for deep crustal structure and velocity model using localized phantom horizons. We model two boundary thrusts at margins of Cuddapah basin and Eastern Ghats Belt formed over the Indian shield during the Rodinia and Columbia supercontinental episodes (1.1 Ga and 1.8 Ga).The results are significant to continental evolution. Imprints of collisional orogeny revealed as two thrust faults on the margins of the structures involved are modelled.

Traditional methods for investigating the subsurface cannot properly investigate fractures between 1m and 100–200m. Digital outcrop models (DOMs) provide a framework for the collection of extensive datasets in outcrop analogues. Here we present a comprehensive workflow, with a solid statistical foundation, for the characterization of all the fracture network parameters that can be obtained from this type of support, including best practices for an optimal outcrop selection and data acquisition.

Geodynamic significance of the tholeiitic series of the Paleoproterozoic greenstone Mako belt (eastern Senegal, West African Craton) has been emigmatic for long time. Using geochemical and isotopic data on minerals and rocks obtained with electron microprobe and ICP-MS, laser ICP-MS and TIMS techniques, we provide evidence for the existence of two tholeiitic and one calc-alkaline series evolving from an oceanic plateau domain to an island arc domain.

The Wufeng to Longmaxi (WF-LMX) Formations are the most important shale gas play in China. Here, we present a feasible approach using nanoindentation to characterize the mechanical properties of the WF-LMX Formations. Mechanical properties varied synchronously with mineral and organic content across the vertical drilling profile, reflecting changes in lithology and sedimentary facies. The effect of shale constituents on micromechanics is essentially controlled by the sedimentary environment.

Passive seismic data were acquired along a 2.8 km long profile in the Sudret area of Gotland, Sweden, as part of a feasibility study for storage of CO₂ below the Baltic Sea. Virtual shot gathers were retrieved by seismic interferometry. Both the body waves and surface waves provide high-quality images of the top of the Ordovician formation and have a good consistency with the borehole section. Our results show that passive data can be used for mapping some general geological features in Gotland.

We propose a new method to map faults automatically in DEMs and measure long-term crustal deformation in rift contexts. By combining our data with rock ages, we reconstruct rift evolution in Afar during the last 4.5 Myrs. We show that the rift axis is most active, with rifting propagating northwest over time. Here magma promotes crustal deformation and faulting caused by dike opening. In the southern sector Afar, two fault systems respond to different motions of diverging tectonic plates.

We used computer models to study how mountains formed by the collision of tectonic plates can later affect the breakup of these same plates. Our results show that in large, warm mountain belts, new faults form due to the orogen being overall weak, while in smaller, colder belts, breakup follows old fault zones. Microcontinents that were accreted during collision can create new continental fragments during extension. These findings help explain how past geological events shape continent margins.

In Germany, claystones are studied for their suitability as host-rocks for the disposal of high-level radioactive waste. The MATURITY project systematically investigates how gradual burial affects key barrier properties in the Lower Jurassic Amaltheenton Formation of the Lower Saxony Basin (Germany). Understanding these changes helps assess claystone suitability for long-term waste isolation, improving site selection for deep geological repositories.

This study applied fat ray travel time tomography to image the geothermal testbed at the BedrettoLab. An active seismic crosshole survey provided a dataset of 42'843 manually picked first breaks. The complex major fault zone was successfully imaged by a 3D velocity model and validated with wireline logs and geological observations. Seismic events from hydraulic stimulation correlated with velocity structures, "avoiding" very high and low velocities, speculatively due to stress gradients.

Reflection seismic data can provide high resolution images of the Earth's crust and allow a better understanding of crustal structure on all continents. In this paper we revisit reflection seismic data that were acquired previously across the central part of the Scandinavian peninsula. Merging of individual components of the data set in a more optimal manner resulted in a new image of the crust below the Scandinavian Caledonides with a revised interpretation of the crustal structure in the west.

Geological storage of CO₂ has emerged again in recent years as a complement to reducing CO₂ emissions to the atmosphere. The Swedish government recently gave the task of further studying the potential for CO₂ storage within Swedish territory to the Geological Survey of Sweden. We report here on results from investigations on southern Gotland island. We find that we can map several geological formations of interest and that the rock is seismically anisotropic.

This study presents a new geological model of the Fano-Pesaro offshore area, refining its tectonic framework. We identified multiple fault detachments at different depths, influencing thrust system dynamics and deformation. This work highlights the importance of integrating seismic and borehole data, even legacy, to build reliable subsurface models. These findings contribute to improved seismic hazard assessment and support offshore energy development and carbon storage projects.

To improve current knowledge of deep geological structures in Hainaut (SW Belgium), a new detailed regional gravity anomaly map has been produced. This has involved the integration and harmonisation of legacy and new non-standardised cross-border gravity data achieved by developing an adaptive and open-source gravimetric workflow. Resulting map shows the correlation between the anomaly and the Meso-Cenozoic thickness deposits but also new anomalies that may be due to deep-seated structures.

Two reflection seismic (semi-)regional profiles were acquired to map the regional reflectivity of the Koillismaa Layered Igneous Complex in north-eastern Finland. Several reflections up to a depth of 5–6 km are mapped. The top of the magma conduit associated with KLIC is successfully revealed and it is interpreted that there might be a second magma conduit below the exposed intrusion. The study helped in better understanding of the regional structural geology of the area.

The manuscript re-analyses seismic data from the UPPLAND profile in the Fennoscandian Shield, focusing on Vp and Vs velocity models. Significant differences between prior and present models emerge in the lower crust and mantle and in the Moho depth. The new model suggests Vp of 7.05–7.17 km/s in the lower crust and 8.05 km/s in the upper mantle, with Moho at 43–50 km. Two tectonic interpretations are proposed to explain these findings, emphasizing the complexities of seismic data interpretation.

We analyse the drainage network in a depressed area in the southern Spain. To do that, we analyzed streams and endorheic basins together with fold and faults. Results showed that the Atlantic-Mediterranean water divide in the study area will probably move NW-ward and the endorheic basins will still endure, hosted in a depressed area located between two active mountain ranges. Our results confirm that active tectonics have reshaped the area more intensively than previously considered.