Recent  

Plume–ridge interaction is an intriguing geological process in plate tectonics. In this paper, we address the respective role of ridgeward vs. plate-drag plume flow in 2D thermomechanical models and compare the results with a compilation of observations on Earth. From a geophysical and geochemical analysis of Earth plumes and in combination with the model results, we propose that the absence of plumes interacting with ridges in the Pacific is largely caused by the presence of plate drag.

We discuss collapse sinkholes occuring since 2004 on the sports field of Münsterdorf, a village north of Hamburg. The sinkholes, 2–5 m in size and about 3–5 m deep, develop in peri-glacial sand, with a likely origin in the Cretaceous chalk, present at about 20 m depth. The area has been analyzed with geophysical and direct-push-based methods, from which material properties of the subsurface have been derived. The properties have been used for mechanical models, predicting the subsidence.

Analogue models of tectonic processes rely on the reproduction of their geometry, kinematics and dynamics. An important property is fault behaviour, which is linked to the frictional characteristics of the fault gouge. This is represented by granular materials, such as quartz sand. In our study we investigate the time-dependent frictional properties of various analogue materials and highlight their impact on the suitability of these materials for analogue models focusing on fault reactivation.

The physical processes leading to the kilometre-scale thermal anomaly in faulted tight sandstones are numerically investigated. The fluid-flow pathways, heat-transfer types and interactions among different convective and advective flow modes are systematically identified. The methodologies and results can be applied to interpret hydrothermal convection-related geological phenomena and to draw implications for future petroleum and geothermal exploration and exploitation in analogous settings.

We analysed Zechstein salt with microscopes and observed specific microstructures that indicate much faster deformation in rock salt with fine halite grains when compared to salt with larger grains. This is important because people build large cavities in the subsurface salt for energy storage or want to deposit radioactive waste inside it. When engineers and scientists use grain-size data and equations that include this mechanism, it will help to make better predictions in geological models.

A THMC multi-field rock resistivity test system is developed, which has the functions of rock triaxial and resistivity testing under the conditions of high and low temperature, high pressure, and high salinity water seepage. A sealing method to prevent the formation of a water film on the side of the specimen is proposed based on the characteristics of the device. The device is suitable for studying the relationship between rock mechanical properties and resistivity in complex environments.

Our study focuses on the correlation of two geophysical parameters (electrical resistivity and density) with geological units. We use this computer-aided correlation to improve interpretation of the Earth’s formation history along the Namibian coast and the associated formation of the South Atlantic Ocean. It helps to distinguish different types of sediment cover and varieties of oceanic crust, as well as to identify typical features associated with the breakup of continents.

Progression of orogenic wedges over pre-existing extensional structures is common in nature, but deciphering the spatio-temporal evolution of deformation from the geological record remains challenging. Our laboratory experiments provide insights on how horizontal stresses are transferred across a heterogeneous crust, constrain which pre-shortening conditions can either favour or hinder the reactivatation of extensional structures, and explain what implications they have on critical taper theory.

By making a change to the way we solve the flexure equation that describes how the Earth's outer layer bends when it is subjected to loading by ice sheets or mountains, we develop new ways of using an old method from geodynamics. This lets us study the Earth's outer layer by measuring a parameter called the elastic thickness, effectively how stiff and springy the outer layer is when it gets loaded and also how the Earth's outer layer gets broken around its edges and in its interior.

Investigation of the global Earth's structure benefits from the analysis of ocean bottom seismometer (OBS) data that allow an improved seismic illumination of dark spots of crustal and mantle structures in the oceanic regions of the Earth. However, recordings from the ocean bottom are often highly contaminated by noise. We developed an OBS noise reduction algorithm, which removes much of the oceanic noise while preserving the earthquake signal and does not introduce waveform distortion.

We study the construction of the Ukrainian Carpathians with LT thermochronology (AFT, AHe, and ZHe) and stratigraphic analysis. QTQt thermal models are combined with burial diagrams to retrieve the timing and magnitude of sedimentary burial, tectonic burial, and subsequent exhumation of the wedge's nappes from 34 to ∼12 Ma. Out-of-sequence thrusting and sediment recycling during wedge building are also identified. This elucidates the evolution of a typical wedge in a roll-back subduction zone.

Submarine landslides commonly appear as low-amplitude zones in seismic data. Previous studies have attributed this to a lack of preserved internal structure. We use seismic modelling to show that an amplitude reduction can be generated even when there is still metre-scale internal structure, by simply deforming the bedding. This has implications for interpreting failure type, for core-seismic correlation and for discriminating landslides from other "transparent" phenomena such as free gas.

The mantle thermal conductivity's dependencies on temperature, pressure, and composition are often suppressed in numerical models. We examine the effect of these dependencies on the long-term evolution of lower-mantle thermochemical structure. We propose that depth-dependent conductivities derived from mantle minerals, along with moderate temperature and compositional correction, emulate the Earth's mean lowermost-mantle conductivity values and produce a stable two-pile configuration.

In this work, a gravity inversion method that can produce compact and sharp images is presented. An auto-adaptive regularization parameter estimation method, improved error-weighting function and combined stopping rule are the contributions incorporated into the presented inversion method. The method is tested by synthetic and real gravity data, and the obtained results confirmed the potential practicality of the method.

In this study, the modelling results are used to help understand the performance of a helically wound fibre (HWC) from a field study at the New Afton mine, British Columbia. We introduce the numerical 3D model to model strain values in HWC to design more effective HWC system. The DAS dataset at New Afton, interpreted in the context of our modelling, serves as a practical demonstration of the extreme effects of surrounding media and coupling on HWC data quality.

Infrequent eruptions of acidic magma are one of the most dangerous natural phenomena, but almost none of them have been witnessed by modern science. We present the first systematic characterization of seismicity recorded near an erupting acidic volcano (Cordón Caulle 2011). We define different phases of unrest and eruption, which combined with previous findings allows us to discuss the main processes associated with this type of violent eruption, with implications for their volcanic hazard.