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Ground and infrastructure stability are important for our technologically based civilization. Infrastructure projects take into consideration the risk posed by ground displacement (e.g., seismicity, geological conditions and geomorphology). To address this risk, earth scientists and civil engineers employ a range of measurement technologies, such as optical/laser leveling, GNSS and, lately, SAR interferometry. Currently there is a rich source of measurement information provided in various formats that covers most of the industrialized world. Integration of this information becomes an issue that will only increase in importance in the future. This work describes a practical approach to address and validate integrated stability measurements through the development of a platform that could be easily used by a variety of groups, from geoscientists to civil engineers and also private citizens with no training in this field. The platform enables quick cross-validation between different data sources, easy detection of critical areas at all scales (from large-scale individual buildings to small-scale tectonics) and can be linked to end-users from various monitoring fields and countries for automated notifications. This work is closing the gap between the specialized monitoring work and the general public, delivering the full value of technology for societal benefits in a free and open manner. The platform is calibrated and validated by an application of SAR interferometry data to specific situations in the general area of the Romanian Carpathians and their foreland. The results demonstrate an interplay between anthropogenically induced changes and high-amplitude active tectono–sedimentary processes creating rapid regional and local topographic variations.

Apart from the lithosphere-asthenosphere boundary (LAB), mid-lithospheric discontinuities (MLDs) in thick and old continental lithospheres appear to play an important role in global plate tectonics. Initiation of intra-continental subduction, delamination of the lower continental lithospheric mantle and removal of cratonic roots are likely to occur along MLDs. Here we introduce the ‘pargasosphere’ hypothesis which could account for the origin of both boundaries. The observation that pargasitic amphibole is stable even at very low bulk ‘water’ concentration (~a few hundreds ppm wt.) implies that the solidus of the shallow upper mantle (

Fluvial morphology is affected by a wide range of forcing factors, which can be external, such as faulting and changes in climate, or internal, such as variations in rock hardness or degree of fracturing. It is a challenge to separate internal and external forcing factors when they are co-located or occur coevally. Failure to account for both factors leads to potential misinterpretations. For example, steepening of channel network due to lithologic contrasts could be misinterpreted to be a function of increased tectonic displacements. These misinterpretations are enhanced over large areas, where landscape properties needed to calculate channel steepness (e.g. channel concavity) can vary significantly in space. In this study, we investigate relative channel steepness over the Eastern Carpathians, where it has been proposed that active rock uplift in the Southeastern Carpathians gives way N- and NW-wards to ca. 8 Myrs of post-orogenic quiescence. We develop a technique to quantify relative channel steepness, the relative steepness index, based on a wide range of concavities, and show that the main signal shows an increase in relative steepness index from east to west across the range. Rock hardness measurements and geological studies suggest this difference is driven by lithology. When we isolate channel steepness by lithology to test for ongoing rock uplift along the range, we find steeper channels in the south of the study area compared to the same units in the North. This supports interpretations from longer timescale geological data that active rock uplift is fastest in the southern Southeastern Carpathians.

Reconstructing orogenic systems made up dominantly by sediments accreted in trenches is challenging because of the incomplete lithological record of the subducted oceanic domain and its attached passive continental margin thrusted by collisional processes. In this respect, the remarkable ~600 km long continuity of sediments exposed in the Eastern Carpathian thin-skinned thrust and fold belt and the availability of quantitative reconstructions for adjacent continental units provide excellent conditions for a paleogeographical study by provenance and sedimentological techniques constraining sediment routing and depositional systems. These sediments were deposited in the Ceahl?u-Severin branch of the Alpine Tethys Ocean and over its European passive continental margin. We report sedimentological, paleomagnetic, petrographic, and detrital zircon U-Pb data of Lower Cretaceous sediments from several thin-skinned tectonic units presumably deposited in the Moldavides domain of the Eastern Carpathians. Sedimentological observations in the innermost studied unit demonstrate that deposition took place in a deepwater basin floor sheets to sandy turbidite system. Detrital zircon age data demonstrate sourcing from internal Carpathian basement units. The sediment routing changes in more external units, where black shales basin floor sheets to sandy mud turbidites were sourced from an external, European continental area. Although some degree of mixing between sources located on both margins of the ocean occurred, constraining a relatively narrow width of the deep oceanic basin, these results demonstrate that the internal-most studied unit was deposited near an Early Cretaceous accretionary wedge, located on the opposite internal side relative to the passive continental margin domain of other Moldavides units.

We provide lithological, sedimentological and micropalaeontological descriptions of 39 sections and boreholes crossing the upper Miocene deposits of the Rifian Corridor. These deposits represent the sedimentary remnants of the marine gateway that connected the Atlantic to the Mediterranean in the late Miocene. Results from these 39 sites were adopted to reconstruct the palaeogeographic evolution of the gateway presented in the associated research article (Capella et al., 2018) [1]. For each outcrop we present a synthesis of field observations, lithofacies, key sedimentological features, planktic and benthic assemblages.

Recent studies imply that the formation and evolution of many SE Asian basins was driven by extensional detachments or systems of low-angle normal faults that created significant crustal exhumation in their footwalls. In this context, the architecture of the Triassic Indosinian orogen presently exposed in Peninsular Malaysia is compatible with significant extension post-dating the orogenic event. In this study we performed a kinematic analysis based on fieldwork and microstructural observations in the Taku Schist, Kemahang granite and the surrounding Gua Musang sediments of northern Peninsular Malaysia in order to shed light on processes related to the build-up and subsequent demise of the Indosinian orogen. The first three phases of deformation were related to an overall period of E–W oriented contraction and burial metamorphism. These phases of deformation are characterized by isoclinal folding with flat lying axial plane cleavages (D1), asymmetrical folding, top-to-the-W–SW shearing (D2) and upright folding (D3). All are in general agreement with observations of the previously inferred Permo–Triassic Indosinian orogeny. During these times, the Taku Schist, a sequence of Paleozoic clastic sediments with mafic intercalations was metamorphosed to amphibolite facies. These rocks are most likely equivalent to the ones exposed in the Bentong–Raub suture zone. Structural relations suggest that the Triassic Kemahang pluton is syn-kinematic, which provides important constraints for the timing of these contractional events. We demonstrate that the overall shortening was followed by a hitherto undescribed extension in NW–SE direction resulting in the formation of a large-scale detachment, the Taku detachment, in northern Peninsular Malaysia. Extension probably reactivated the former subduction plane as a detachment and exhumed previously buried and metamorphosed rocks of similar lithological composition to the neighboring Bentong–Raub suture zone. Such a mechanism is similar to that observed in other regions, such as the Aegean, Apennines, Dinarides or the Betics–Rif system, where exhumation of (high-pressure) metamorphic rocks is largely controlled by detachments or low angle normal shear/fault systems.

Extensional basins often show along-strike variability in terms of fault geometries, basement structures, subsidence, and thermal evolution. This is particularly pronounced when extension reactivates preexisting suture zones with opposing dip directions, that is, opposite polarities, which creates wide strike-slip transfer zones. We have studied this extensional variability by means of thermomechanical lithospheric-scale 3-D numerical modeling. We conducted a series of experiments to model the extension of a thick lithosphere simulating a young orogenic area containing segmented suture zones inherited from former opposing subduction polarities, implemented as rheologically weak inclined layers with opposite dips. Numerical experiments demonstrate that the initial subduction sutures are reactivated by two long-lived lithospheric-scale detachment faults, which remain active until the onset of oceanic spreading. The opposite polarity of these faults causes their migration toward each other by asymmetric mantle lithosphere extension and thermal accretion. Crustal kinematics shows the formation of extensional detachment faults and high-offset listric normal faults. These structures undergo gradual tilting during their footwall exhumation, while the rheological weak suture layers are redistributed beneath the crust. The results demonstrate an active interaction along the strike of the system between the two opposite dipping weak zones, where fault segments mechanically interact. During extension, the maximum horizontal fault offset switches the apparent sense of shear in the separating strike-slip transfer zone. This kinematics explain the rapid change in the sense of shear in major strike-slip transfer zones or transform faults, such as observed during the extension of the Pannonian back-arc basin.

The Rifian Corridor was one of the Mediterranean–Atlantic seaways that progressively restricted and caused the Messinian Salinity Crisis (MSC). Many key questions concerning the controls on the onset, progression and termination of the MSC remain unanswered mainly because the evolution of these seaways is poorly constrained. Uncertainties about the age of restriction and closure of the Rifian Corridor hamper full understanding of the hydrological exchange through the MSC gateways: required connections to sustain transport of salt into the Mediterranean for the primary-lower gypsum and halite stages. Here we present integrated surface-subsurface palaeogeographic reconstructions of the Rifian Corridor with improved age-control. Information about age and timing of the closure have been derived from high-resolution biostratigraphy, palaeoenvironmental indicators, sediment transport directions, and the analysis of published onshore subsurface (core and seismic) datasets. We applied modern taxonomic concepts to revise the biostratigraphy of the Rifian Corridor and propose astronomically-tuned, minimum-maximum ages for its successions. Finally, we summarise the palaeogeographic evolution in four time slices corresponding to the middle Tortonian (10.57–8.37), late Tortonian (8.37–7.25 Ma), early Messinian (7.25–6.35 Ma), and late Messinian (6.35–5.33 Ma). Several successions record the closure of the corridor via a continuous marine to continental-lacustrine transition. The youngest dated marine sediments represent a good approximation of the age of seaway closure. The closure of the South Rifian Corridor is constrained to 7.1–6.9 Ma; that of the North Rifian Corridor is more uncertain and ranges from 7.35 to ca. 7 Ma. We conclude that the Rifian Corridor was already closed in the early Messinian and did not contribute to the restriction events that resulted in the MSC. Because the Betic Corridor is also closed by the early Messinian, the modern Gibraltar Straits remain the sole option in the Western Mediterranean as last Messinian seaway that was open during the MSC. Our results imply that the Gibraltar Straits could have been established as the exclusive Mediterranean-Atlantic portal already in the late Miocene, and therefore we suggest that future field and drilling campaigns should target the Alboran Sea and the Gibraltar region to investigate water exchange before and during the Messinian Salinity Crisis and its impact on Atlantic circulation and global climate.

Fragmentation of large continental areas by post-orogenic extension requires favourable geodynamic conditions and frequently occurs along pre-existing suture zones or nappe contacts, as exemplified by the Stong and Taku magmatic and metamorphic complexes of northern Peninsular Malaysia. For this case, we have employed a field and microstructural kinematic study combined with low temperature thermo-chronology to analyse the tectonic and exhumation history. The results show that the Late Palaeozoic - Triassic Indosinian orogeny created successive phases of burial related metamorphism, shearing and contractional deformation. This orogenic structure was subsequently dismembered during a Cretaceous thermal event that culminated in the formation of a large scale Late Santonian - Early Maastrichtian extensional detachment, genetically associated with crustal melting, the emplacement of syn-kinematic plutons and widespread migmatisation. The emplacement of these magmatic rocks led to an array of simultaneously formed structures that document deformation conditions over a wide temperature range, represented by amphibolite- and greenschist- facies mylonites and as well as brittle structures, such as cataclastic zones and normal faults that formed during exhumation in the footwall of the detachment. The formation of this detachment and a first phase of Late Cretaceous cooling was followed by renewed Eocene - Oligocene exhumation, as evidenced from our fission track ages. We infer that an initial Cretaceous thermal anomaly was responsible for the formation of an extensional gneiss dome associated with simple shear and rotation of normal faults. These Cretaceous processes played a critical role in the establishment of the presently observed crustal structure of Peninsular Malaysia.

An overview on the tectono-stratigraphic framework of the Arabian plate indicates obvious differences between two distinct areas: the hydrocarbon-prolific sector and non-hydrocarbon-prolific sector. These differences resulted from the interplay of a variety of factors; some of which are related to the paleo-geographic configuration (eustatic sea level fluctuations, climatic conditions, and salt Basins), others to differential subsidence (burial) and structural inversions. During the Paleozoic, the regional compression was caused by far field effects of the Hercynian orogeny. This led to major folded structures in central and eastern Saudi Arabia (e.g. Ghawar anticline). During the Mesozoic, the most important tectonic factor was the stretching of the crust (extension), accompanied with the increase in temperature, resulting in an increase of the accommodation space, and thicker sedimentary successions. Regional unconformities are mostly found where folded structures are dominant, and they acted as a carrier systems for the accumulation of hydrocarbon and groundwater. A good understanding of the stratigraphy and tectonic evolution is, thus, required to develop carbon capture and storage (CCS) and to design efficiently enhanced oil recovery (EOR) in both sectors. Oil and gas reservoirs offer geologic storage potential as well as the economic opportunity of better production through CO2-EOR. The world greatest hydrocarbon reservoirs mainly consist of Jurassic carbonate rocks, and are located around the Arabian Basin (including the eastern KSA and the Arabian Gulf). The Cretaceous reservoirs, which mainly consist of calcarenite and dolomite, are located around the Gotnia salt Basin (northeast of KSA). Depleted oil and gas fields, which generally have proven as geologic traps, reservoirs and seals, are ideal sites for storage of injected CO2. Each potential site for CO2-EOR or CCS should be evaluated for its potential storage with respect to the containment properties, and to ensure that conditions for safe and effective long term storage are present. The secured deep underground storage of CO2 implies appropriate geologic rock formations with suitable reservoir rocks, traps, and impermeable caprocks. Proposed targets for CCS, in the non-hydrocarbon-prolific sector, are Kharij super-aquifer (Triassic), Az-Zulfi aquifer (Middle Jurassic), Layla aquifer (Late Jurassic), and Wasia aquifer (Middle Cretaceous). Proposed targets for EOR are Safaniya oil field (Middle Cretaceous) (Safaniya, Wara and Khafji reservoirs), Manifa oil field (Las, Safaniya and Khafji reservoirs) (Late Jurassic), and Khuff reservoir (Late Permian-Early Triassic) in central to eastern KSA.

The architecture of sedimentary basins reflects the relationship between accommodation space and sediment supply, their rates and localization being variable during basin evolution. The mechanisms driving the interplay between tectonics and sedimentation in extensional back-arc basins overlying rheological weak zones inherited from an earlier orogenic evolution are less understood. A typical example is the Pannonian back-arc basin of Central Europe. It is floored by continental lithosphere and was affected by large amounts of extension driven by the subduction rollback that took place in the Carpathians and/or Dinarides. A novel kinematic and seismic sequence stratigraphic interpretation calibrated by wells allows the quantification of the link between the formation of half grabens and coeval sedimentation in the Great Hungarian Plain part of the basin. While the lower order tectonic-induced cycles characterize the main phases of extension in various subbasins, the higher-order cyclicity and associated unconformities define individual moments of fault (re)activation. Our novel interpretation of a temporal and spatial migration of extension during Miocene times explains the contrasting present-day strike of various subbasins as a result of their gradual clockwise rotation. Incorporating the observed asymmetry, in particular the associated footwall exhumation, infers that the amount of extension is much larger than previously thought. The quantitative link between tectonics and sedimentation has allowed the definition of a novel model of sedimentation in asymmetric basins that can be ported to other natural scenarios of similarly hyperextended back-arc basins observed elsewhere.

The tectonic evolution of sedimentary basins is the intrinsic result of the interplay between lithospheric stresses, lithospheric rheology, and thermal perturbations of the lithosphere–upper mantle system. The thermomechanical structure of the lithosphere exerts a prime control on its response to basin-forming mechanisms, in both extension and compression. Tectonic reactivation has strongly affected the structure and fill of many sedimentary basins. The long-lasting rheological memory of the lithosphere appears to play a far more important role in basin reactivation than hitherto assumed. The temporal evolution of the strength of continents and the spatial variations in stress and strength at continental margins, rifts, and orogenic belts govern the mechanics of basin development in time and space. Polyphase deformation is a common feature of many sedimentary basin systems. Compressional reactivation of extensional basins during their postrift phase appears to occur in many intraplate rifts and passive margins, reflecting temporal and spatial changes in the orientation and magnitude of the intraplate stress regime. Similarly, foreland basins are frequently characterized by preorogenic extension. The actual subsidence patterns of these polyphase systems are often more complex than predicted by end-member models that only consider the basin formation mechanism. Folding of the lithosphere, involving positive and negative deflections, appears to be of more importance in the large-scale deformation of intraplate domains than hitherto realized. In the intraplate domain of continental Europe that was thermally perturbed by Cenozoic upper mantle plume activity, lithospheric folding, for instance, plays an important role and strongly affects the pattern of vertical motions, in terms of both the basin subsidence and the uplift of broad arches. Tectonic processes operating during basin formation and during the subsequent deformation of basins can generate significant differential topography in basin systems. In view of the close link between erosion of topographic highs and sedimentation in subsiding areas, constraints are needed on uplift and coeval subsidence to validate quantitative process-oriented models for the evolution of sedimentary basins. Integration of analog and numerical modeling provides a novel approach to assess the feedback mechanisms between deep mantle, lithospheric, and surface processes.

Sedimentary basins are affected by a large number of forcing factors during their evolution and as a result, it is often difficult to isolate the contribution of each individual factor. Many forcing factors are temporally and spatially heterogeneous; they do not affect all parts of the basin in the same way and at the same time. We show that this heterogeneity can be used to identify the contributions of forcing factors by comparing various parts of a basin. This approach is applied to the Pannonian Basin, a back-arc basin located in Central Europe. In the basin, the amounts of crustal extension, tectonic inversion and sediment influx varied in space and time, while the connection with the marine realm fluctuated. In this study we focus on two currently unresolved issues: firstly, we establish by what processes and from what directions the basin was filled in, and secondly, we investigate whether the basin was affected by the Messinian Salinity Crisis. The analysis of seismic and well data in the previously less studied SE part of the basin demonstrate that progradation occurred from the southern and eastern basin margins, complementing the previously described progradation from the northwestern and northern basin margins. Elsewhere in the basin, an unconformity observed in the progradational basin infill is intensely debated to be the result of either the Messinian Salinity Crisis (MSC) or basin inversion. Having the advantage of minor Pliocene–Quaternary amounts of inversion in the studied part of the basin we show that no regional unconformity is present in the studied stratigraphic interval, which implies that the effects of the MSC on the basin were minor. We infer that being aware of the fact that the effects of relative sea/lake-level fluctuations may vary significantly across a basin is critical for understanding the evolution of semi-enclosed basins.

Understanding the interactions between surface and deep Earth processes is important for research in many diverse scientific areas including climate, environment, energy, georesources and biosphere. The TOPO-EUROPE initiative of the International Lithosphere Program serves as a pan-European platform for integrated surface and deep Earth sciences, synergizing observational studies of the Earth structure and fluxes on all spatial and temporal scales with modelling of Earth processes. This review provides a survey of scientific developments in our quantitative understanding of coupled surface-deep Earth processes achieved through TOPO-EUROPE. The most notable innovations include (1) a process-based understanding of the connection of upper mantle dynamics and absolute plate motion frames; (2) integrated models for sediment source-to-sink dynamics, demonstrating the importance of mass transfer from mountains to basins and from basin to basin; (3) demonstration of the key role of polyphase evolution of sedimentary basins, the impact of pre-rift and pre-orogenic structures, and the evolution of subsequent lithosphere and landscape dynamics; (4) improved conceptual understanding of the temporal evolution from back-arc extension to tectonic inversion and onset of subduction; (5) models to explain the integrated strength of Europe's lithosphere; (6) concepts governing the interplay between thermal upper mantle processes and stress-induced intraplate deformation; (7) constraints on the record of vertical motions from high-resolution data sets obtained from geo-thermochronology for Europe's topographic evolution; (8) recognition and quantifications of the forcing by erosional and/or glacial-interglacial surface mass transfer on the regional magmatism, with major implications for our understanding of the carbon cycle on geological timescales and the emerging field of biogeodynamics; and (9) the transfer of insights obtained on the coupling of deep Earth and surface processes to the domain of geothermal energy exploration. Concerning the future research agenda of TOPO-EUROPE, we also discuss the rich potential for further advances, multidisciplinary research and community building across many scientific frontiers, including research on the biosphere, climate and energy. These will focus on obtaining a better insight into the initiation and evolution of subduction systems, the role of mantle plumes in continental rifting and (super)continent break-up, and the deformation and tectonic reactivation of cratons; the interaction between geodynamic, surface and climate processes, such as interactions between glaciation, sea level change and deep Earth processes; the sensitivity, tipping points, and spatio-temporal evolution of the interactions between climate and tectonics as well as the role of rock melting and outgassing in affecting such interactions; the emerging field of biogeodynamics, that is the impact of coupled deep Earth – surface processes on the evolution of life on Earth; and tightening the connection between societal challenges regarding renewable georesources, climate change, natural geohazards, and novel process-understanding of the Earth system.