We used laboratory experiments to simulate the early evolution of rift systems, and the influence of structural weaknesses left over from previous tectonic events that can localize new deformation. We find that the orientation and type of such weaknesses can induce complex structures with different orientations during a single phase of rifting, instead of requiring multiple rifting phases. These findings provide a strong incentive to reassess the tectonic history of various natural examples.

Two time-lapse borehole ground penetrating radar (GPR) surveys were conducted during saline tracer experiments in weakly fractured crystalline rock with sub-millimeter fractures apertures, targeting electrical conductivity changes. The combination of time-lapse reflection and transmission GPR surveys from different boreholes allowed monitoring the tracer flow and reconstructing the flow path and its temporal evolution in 3D and provided a realistic visualization of the hydrological processes.

Vertical incidence seismic profiling on the Iberian Massif images a mid-crustal-scale discontinuity at the top of the reflective lower crust. This feature shows that upper- and lower-crustal reflections merge into it, suggesting that it has often behaved as a detachment. The orogen-scale extension of this discontinuity, present in Gondwanan and Avalonian affinity terranes into the Iberian Massif, demonstrates its relevance, leading us to interpret it as the Conrad discontinuity.

In partially molten regions within the Earth, the melt is able to move separately from the surrounding rocks. This allows for the emergence of so-called solitary porosity waves, driven by compaction and decompaction due to the melt with higher buoyancy. Our numerical models can predict whether a partially molten region will ascend dominated by solitary waves or diapirism. Even in diapiris-dominated regions, solitary waves will build up and ascend as a swarm when the ascend time is long enough.

In our study, we show the results of a passive seismic interferometry application for mapping the uppermost crust in the area of active mineral exploration in northern Finland. The obtained velocity models agree well with geological data and complement the results of reflection seismic data interpretation.

The construction of tunnels leads to substantial alterations of the surrounding rock, which can be critical concerning safety aspects. We use different mobile methods to assess the hydromechanical properties of an excavation damaged zone (EDZ) in a claystone. We show that long-term exposure and dehydration preserve a notable fracture permeability and significantly increase strength and stiffness. The methods are suitable for on-site monitoring without any further disturbance of the rock.

As the travel time of seismic waves depends on the Earth's interior properties, seismic tomography uses it to infer the distribution of velocity anomalies, similarly to what is done in medical tomography. We propose analysing the outputs of those models using varimax principal component analysis, which results in a compressed objective representation of the model, helping analysis and comparison.

Using the AlpArray seismic network, we have determined highly accurate travel times of P waves from over 370 major global earthquakes between 2015 and 2019, which shall be used for a tomography of the mantle beneath the greater Alpine region. Comparing with theoretical travel times of a standard reference earth model, we receive very stable patterns of travel-time differences across the network which provide evidence of varying subduction behaviour along the strike of the Alpine orogen.

This work features the highest-resolution seismic stress and strain fields available at the present time for the analysis of the active crustal deformation of the Western Alps. In this paper, we address a large dataset of newly computed focal mechanisms from a statistical standpoint, which allows us to suggest a joint control from far-field forces and from buoyancy forces on the present-day deformation of the Western Alps.

The localization of an earthquake is affected by many uncertainties. To correctly propagate these uncertainties into an estimate of the earthquake coordinates and their associated errors, many simulations of seismic waves are needed. This operation is computationally very intensive, hindering the feasibility of this approach. In this paper, we present a series of deep-learning methods to produce accurate seismic traces in a fraction of the time needed with standard methods.