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This paper discusses recent archaeological fieldwork conducted at El Castillejo, a medieval Islamic settlement in Los Guájares, Granada, southern Spain. Results from combined archaeological excavation and archaeoseismological assessment of standing structures suggest that the site was affected by a destructive earthquake during its occupation. Radiocarbon samples and OSL analysis point to a seismic event in the period CE 1224–1266. The earthquake occurred within an area marked by a 'seismological gap' in terms of historic seismicity and the causative fault has been tentatively identified in the Nigüelas-Padul Fault System which lies north of the settlement. This event is not recorded by national or European seismic catalogues and represents the oldest historic earthquake in the Granada area. Our work stresses the significant impact that targeted archaeological investigations can generate in our understanding of the local historic seismicity, thus providing clear implications for seismic disaster prevention and reduction. [ABSTRACT FROM AUTHOR]

In eastern Crete, several normal faults trend both NNE-SSW and E-W. Most of them form impressive bedrock fault scarps indicating ongoing extension in the Hellenic fore-arc. No earthquakes from historical and instrumental catalogues can be directly associated with these faults. Geomorphologic profiles across five different faults in sites well-preserved from erosion, deposition or human intervention revealed displacements of ∼6.9 m–∼30 m. Following a robust site selection at the Lastros and Orno faults, we mapped different categories of weathered horizontal ribbons along the bedrock fault plane based on colour contrast, lichen colonisation and karstic features that affect fault plane roughness, features that altogether are interpreted as earthquake horizons. The data indicate coseismic displacements of 15–35 cm for the last three earthquakes at the Lastros fault and 10–20 cm for the last two earthquakes at the Orno fault. To constrain the age of these earthquakes and to estimate millennial fault slip rates, we determined cosmogenic 36Cl concentrations from vertical profiles composed of 24 samples from the exposed Lastros fault plane and 7 samples of the Orno fault plane. Bayesian Markov Chain Monte Carlo (MCMC) modelling implies that the last three earthquakes at the Lastros fault, occurred within the last 1.8 ± 1.2 kyr (EQ1 = 1.1 ± 1.1 kyr, EQ2 = 1.4 ± 1.1 kyr, EQ3 = 1.8 ± 1.2 kyr). Furthermore, Lastros' slip rate varied with a rate of 0.6 ± 0.3 mm/yr during the last 1.8 ± 1.2 kyr, preceded by a rate of 1.1 ± 0.4 mm/yr from ∼1.8 to 8 kyr; suggesting periods of earthquake clustering. At the Orno fault, the last two earthquakes occurred within the last ∼3.5 kyr accompanied with a slip rate of 0.16+0.06 -0.02 mm/yr during postglacial times. This confirms for the first time based on absolute dating, that both NNE-SSW and E-W trending neighbouring faults in Crete were active during the Holocene. Most of the 13.2 m high Orno fault scarp was exhumed during glacial times, with an apparent slip rate of 0.28+0.12 -0.07 mm/yr. The upper part of the Lastros fault scarp (9–12 m) and the apparent age of the four Lastros footwall samples (∼17.9 kyr, ∼26.0 kyr, ∼29.9 kyr, ∼37.4 kyr) underline the long preservation throughout glacial times as well. These findings show that the general hypothesis of predominantly postglacial bedrock fault scarps needs to be regarded with caution at lower latitudes and/or low altitudes (<1000 m), since degradation processes are weaker. • Cosmogenic dating on postglacial scarps confirms that both NNW-SSE and E-W trending faults were active during the Holocene. • M∼6.4 palaeoearthquakes have a mean recurrence interval of 200–400 yrs on the Lastros and 600–2000 yrs on theOrno fault. • Postglacial slip rate variability of the Lastros fault between ∼0.6 and ∼1.1 mm/yr. • Uppermost free-faces preserved during glacial times, implying weak degradation in lower latitudes and <1000 m altitude. [ABSTRACT FROM AUTHOR]

Abstract The Asian plate interiors are known to have host strong earthquakes with magnitudes up to M ≈ 8 in recent history, especially around the border area between Mongolia, Kazakhstan, China and Russia (e.g., M7.3 Chuya earthquake, 2003). Their recurrence times seem to be long, because of the relative low slip rates (<1 mm/y) of the faults which caused them. In this study, we focus on a large inherited fault zone (namely the Irtysh Fault Zone) with no historical earthquakes larger than M6, to test whether this structure could have generated surface-rupturing events during the last thousands of years, like some other historically silent similar faults of cratonic southern Kazakhstan did in pre-historic times. To do so, we use tectonic-morphological analyses of satellite images and trenching across several fault portions to detect potential paleoearthquakes. The Irtysh Fault Zone (IFZ) is a 250+ km long basement set of faults that marks a major tectonic block boundary between different units with Paleozoic magmatic rocks and thick deposits of Late Paleozoic age. The formation of the IFZ dates back into the Late Paleozoic times during collision between Siberia-Kazakh cratons and it was repeatedly reactivated in later times (e.g., Oligo-Miocene). The Quaternary activity of the Irtysh Fault Zone has never been addressed in modern studies and, in this study, we document for the first time that the IFZ is an active fault and is a potential source of large earthquakes in easternmost Kazakhstan. Our analyses actually revealed, at different spots along the IFZ, the occurrence of a set of lineaments offsetting lithologies or deflecting streams and other landscape features. Trenching sites across those lineaments eventually confirmed that they were active fault strands and in some trenches, 14C-dated Holocene-Late Pleistocene deposits are clearly faulted. Those recent deposits include organic soils, loess layers and colluvium directly overlying the Paleozoic rocks. Our findings lead to the conclusions that the IFZ is clearly active along several strands of its trace in bedrock. During the Holocene, it hosted earthquakes with surface rupture individual displacements of up to 1.5 m, suggesting events with a magnitude around M ≈ 7. However, our investigations do not allow to confident estimation of slip rates: we propose for one fault section parallel to the main fault a preliminary estimation of ~0.22 mm/y vertical displacement rate, based on a single trench. Based on regional morphoclimatic arguments and landscape features offsets, we also propose a first assessment of the lateral slip rate along the major fault between 0.3 and 0.5 mm/y. Additional investigations should be undertaken to refine surface fault mapping, the paleoearthquake calendar, the slip rate, and potential along-strike evolution, in order to constrain future seismic hazard analyses with fault models in this region of Eastern Kazakhstan. Highlights • We evidence for the first time the Quaternary activity of the Irtysh fault, eastern Kazakhstan. • The morphological signature of the fault in the bedrock involves scarps and drainage deflections and other landscape features. • Several trenches suggest the occurrence of M ~6.5 to 7 surface-rupturing paleoearthquakes during the Holocene. • This fault is typical of a stable continental region, with low slip rates (<1 mm/y) and rare large events. [ABSTRACT FROM AUTHOR]

The coastlines around the Gulf of Cádiz were affected by numerous tsunami events damaging infrastructure and causing countless human losses. A tsunami deposit at Barbate–Zahara de los Atunes, Spain, is located at various heights above mean sea level and shows several characteristics indicative of high-energy event deposition. This study uses sedimentology, foraminifera assemblage, magnetic susceptibility, X-ray fluorescence analysis, ground penetrating radar (GPR) to support an interpretation of high-energy deposition and determine the deposit's transport mechanisms and sediment source. Radiocarbon and optically stimulated luminescence dating of the tsunami deposit reveals ages of ~ 4000 BP and does not support the AD 1755 Lisbon event as suggested in former publications. [ABSTRACT FROM AUTHOR]

Coastal areas are densely populated and therefore vulnerable to the impact of flooding events induced by tsunami waves or storm surges. The flood risk has increased due to global climate change and an accelerated sea-level rise as observed during the most recent geological times (the Anthropocene). At the same time a concentration of settlements along the world's coastlines is observed. Therefore, knowledge of maximum flooding levels during high-energy events is essential to improve the assessment of risk. We utilise wrack lines composed of litter as in situ physical marks made up of durable, solid matter of various compositions to delineate the maximum flooding level. These deposits may enclose information on production dates, used to precisely reconstruct the timing of the flooding. This approach allows an ultra-high resolution dating. We demonstrate the application of this efficient, fast and cheap method for the coastline of Oman bordering the Arabian Sea (Northern Indian Ocean). The area was recently affected by devastating tropical cyclones as well as tsunamis. [ABSTRACT FROM AUTHOR]

A palaeostress analysis of an active bedrock normal fault scarp based on kinematic indicators is reconstructed using terrestrial laser scanning (TLS). For this purpose, three key elements are necessary for a defined region: (i) the orientation of the fault plane, (ii) the orientation of the slickenside lineation or other kinematic indicators, and (iii) the sense of motion of the hanging wall. The paper specifies a workflow in order to obtain stress data from point cloud data using terrestrial laser scanning (TLS) in an active tectonic environment. The entire analysis was performed on a continuous limestone bedrock normal fault scarp on the island of Crete, Greece, at four different locations along the WNW–ESE striking Spili Fault. At each location we collected data with the terrestrial light detection and ranging system (t-LiDAR). We then validated the calculated three-dimensional stress results at three of the locations by comparison with conventional methods using data obtained manually with a compass clinometer. Numerous kinematic indicators for normal faulting were discovered on the fault plane surface using t-LiDAR data. When comparing all reconstructed stress data obtained from t-LiDAR to that obtained through manual compass measurements, the degree of fault plane orientation divergence is ±005/03 for dip direction and dip. The degree of slickenside lineation divergence is ±003/03 for dip direction and dip. Therefore, the percentage threshold error of the individual vector angle at each investigation site is lower than 3% for the dip direction and dip for planes, and lower than 6% for the strike. The maximum mean variation of the complete calculated stress tensors is ±005/03. [ABSTRACT FROM AUTHOR]

The Strait of Gibraltar area is part of the western Eurasian-African convergence zone characterized by a complex pattern of deformation, including thrusting and folding and active normal faulting. Generally, the area is of low-seismicity; only some minor earthquakes have been recorded in the last hundred years. Archaeoseismological data evidences earthquake destruction occurring twice during Roman times. A better neotectonic framework and knowledge on the paleostress evolution of the Strait of Gibraltar area is necessary to find the local sources for those events and to establish an understanding of the recent deformation. Paleoseismic evidence for one moderate earthquake event around 6000-5000 BP along the normal Carrizales Fault is described in this paper. Off-shore high-resolution seismic investigations, structural and paleostress data, high-resolution GPR and geoelectrical resistivity measurements, outcrop investigations and trenching studies are discussed. The data reveal that active faulting takes place along N–S trending normal faults. Hence, N–S directed normal faults in the area are claimed as local candidates for moderate earthquake activity. Return periods of moderate earthquakes in the order of at least 2000–2500 years in the study area may have to be taken into account. Structural data, such a paleostress data and joints are presented and a deformation history for the Strait of Gibraltar area in southern Spain is developed in this study. [ABSTRACT FROM AUTHOR]

A 1,460-m-long profile of a Late Glacial subglacial, glacio-fluvial, glacio-limnic and glacio-deltaic sequence exposed at a cliff section on Usedom Island (SW Baltic Sea coast) is described. The sequence is up to 31 m thick and shows sedimentary structures typical of a glacial setting. Soft-sediment deformation is encountered and is associated with changes in lithology. These deformations include liquefaction, slumping, and faulting. As the most plausible cause, earthquake-induced shaking is discussed. The associated neotectonic activity is seen as a consequence of the postglacial isostatic crustal rebound. As the deglaciation earthquake ratio diminishes with time and as the rebound is phasing out, no large earthquakes are anticipated for northern Germany, although in conclusion the lithosphere of the North German Basin has to be regarded as weakened by repeated ice loading and deloading. [ABSTRACT FROM AUTHOR]

Abstract: During archaeological and geotechnical investigations, the Carolingian part of the Aachen Cathedral (Germany) was excavated. The Aachen Cathedral was the first building in Germany to join the UNESCO World Heritage list. In the rock walls of the fundament and medieval floors, open cracks were found. Subsidence of the mortar floor of about 50 cm with lateral dragging, which was reconstructed during the construction of the Cathedral, can be observed. The main building is founded on Devonian limestones and shales, Pleistocene loess and Roman urban debris. The loess and loamy sediments show angular cracks and fragments, which are not related to permafrost features but are interpreted as shear and extensional fractures. Some of the cracks are filled with black clay from below as they open downwards. These structures are interpreted as injection features caused by thixotropy of clays. Open cracks, lateral spread and injections structures occur usually during earthquakes with a magnitude higher than 5.5. The historical German earthquake catalogues provide three important passages for historical earthquakes in the region of Aachen. Both fall into a relatively short time interval. One occurred in winter 803 AD, another one in 823 AD, and the last one in 829 AD between Ash Wednesday and Easter. Both notes tell of earthquake shaking and significant structural damage and fatalities. This and the constructional history allowed dating of the event, favouring the 803 AD event as the causative damaging earthquake observed in the Aachen Cathedral. [Copyright &y& Elsevier]

Abstract: Lake Ohrid, at the Macedonian/Albanian border, was likely tectonically formed during the Tertiary and therefore is one of the oldest lakes in Europe. However, only a few studies exist concerning the potential of Lake Ohrid sediments for long-term palaeoenvironmental reconstructions within the scope of future potential deep-drilling campaigns. Therefore, as a first step, a transect of short surface sediment cores was investigated for chronology, physical properties, grain size, and biogeochemistry. The results were compared with information derived from a shallow hydro-acoustic seismic survey. The investigations indicate a rather uniform and bioturbated sedimentation in the central part of the lake basin with mean sedimentation rates of ca. 0.5–1 mm/year. The sediment composition is dominated by authigenetic carbonates. Diatom frustules or fragments form the major part of biogenic matter deposits, as indicated by the relatively high contents of biogenic opal and low contents of total organic carbon and total nitrogen. The shallow hydro-acoustic seismic survey indicates that horizons of sediment redeposition occur sporadically. Towards the shore of the lake, the sedimentation rate increases and sedimentation is increasingly influenced by local inflows or mass-movement processes triggered by tectonic activities. Thus Lake Ohrid has a high potential for palaeoenvironmental reconstructions on a multi-decadal scale and provides additional information concerning tectonic activity in the region. [Copyright &y& Elsevier]

Abstract: Paleostress orientations were calculated from fault-slip data of 36 sites located along a traverse through the Central Betic Cordilleras (southern Spain). Heterogeneous fault sets, which are frequent in the area, have been divided into homogeneous subsets by cross-cutting relationships observed in the field and by a paleostress stratigraphy approach applied on each individual fault population. The state of stress was sorted according to main tectonic events and a new chronology is presented of the Miocene to Recent deformation in the central part of the Betic Cordilleras. The deviatoric stress tensors fall into four distinct groups that are regionally consistent and correlate with three Late Oligocene–Aquitanian to Recent major tectonic events in the Betic Cordilleras. The new chronology of the neotectonic evolution includes, from oldest to youngest, the following main tectonic phases: [(1)] Late Oligocene–Aquitanian to Early Tortonian: σ 1 subhorizontal N–S, partly E–W directed, σ 3 subvertical; compressional structures (thrusting of nappes, large-scale folding) and strike-slip faulting in the Alborán Domain and the External Zone of the Betic Cordilleras; [(2)] Early Tortonian to Pliocene–Pleistocene: σ 1 subvertical, σ 3 subhorizontal NW–SE, partly N–S directed or E–W-directed (radial extension); large-scale normal faulting in the Central Betic Cordilleras and in the oldest Neogene formations of the Granada Basin related to the gravitational collapse of the Betic Cordilleras and the exhumation of the intensely metamorphosed rock series of the Internal Zones, at the same time formation of the Alborán Basin and intramontane basins such as the Granada Basin; [(3)] Pleistocene to Recent: (3a) σ 1 subvertical, σ 3 subhorizontal NE–SW with prominent normal faulting, but coevally; (3b) σ 1 subhorizontal NW directed, σ 3 NE–SW subhorizontal with strike-slip faulting. Extensional structures and strike-slip faulting are related to the ongoing convergence of the Eurasian and African Plates and coeval uplift of the Betic Cordilleras. Reactivation of pre-existing fractures and faults was frequently observed. Phase 3 is interpreted as periodic strike-slip and normal faulting events due to a permutation of the principal stress axes, mainly σ 1 and σ 2. [Copyright &y& Elsevier]

The region around the town Albstadt, SW Germany, was struck by four damaging earthquakes with magnitudes greater than 5 during the last century. These earthquakes occurred along the Albstadt Shear Zone (ASZ), which is characterized by more or less continuous microseismicity. As there are no visible surface ruptures that may be connected to the fault zone, we study its characteristics by its seismicity distribution and faulting pattern. We use the earthquake data of the state earthquake service of Baden-Württemberg from 2011 to 2018 and complement it with additional phase picks beginning in 2016 at the AlpArray and StressTransfer seismic networks in the vicinity of the ASZ. This extended data set is used to determine new minimum 1-D seismic vp and vs velocity models and corresponding station delay times for earthquake relocation. Fault plane solutions are determined for selected events, and the principal stress directions are derived. The minimum 1-D seismic velocity models have a simple and stable layering with increasing velocity with depth in the upper crust. The corresponding station delay times can be explained well by the lateral depth variation of the crystalline basement. The relocated events align about north–south with most of the seismic activity between the towns of Tübingen and Albstadt, east of the 9 ∘ E meridian. The events can be separated into several subclusters that indicate a segmentation of the ASZ. The majority of the 25 determined fault plane solutions feature an NNE–SSW strike but NNW–SSE-striking fault planes are also observed. The main fault plane associated with the ASZ dips steeply, and the rake indicates mainly sinistral strike-slip, but we also find minor components of normal and reverse faulting. The determined direction of the maximum horizontal stress of 140–149 ∘ is in good agreement with prior studies. Down to ca. 7–8 km depth SHmax is bigger than SV ; below this depth, SV is the main stress component. The direction of SHmax indicates that the stress field in the area of the ASZ is mainly generated by the regional plate driving forces and the Alpine topography. [ABSTRACT FROM AUTHOR]

Seismic characterization of the Albstadt Shear Zone, GermanyThe region around the town of Albstadt, SW Germany, is one of the most seismically active regions in Central Europe. In the last century alone three earthquakes with a magnitude greater than five happened and caused major damage. The ruptures occur along the Albstadt Shear Zone (ASZ), an approx. 20-30 km long, N-S striking fault with left-lateral strike slip. As there is no evidence for surface rupture the nature of the Albstadt Shear Zone can only be studied by its seismicity.To characterize the ASZ we currently complement the earthquake catalog of the earthquake service of the state of Baden-Württemberg with additional seismic phase onsets. For the latter we use the station network of AlpArray as well as five additional recently installed seismic stations from the KArlsruhe BroadBand Array. We use all seismic stations in the region to search for small magnitude earthquakes. In addition, we invert for a new seismic minimum 1D-velocity model of the study region. All this information is used to determine the potential rupture planes and a possible segmentation of the ASZ. We thank the Landeserdbebendienst in Freiburg for using their data (Az. 4784//18_3303). [ABSTRACT FROM AUTHOR]

The RV Meteor M152 expedition mapped and sampled two transects perpendicular to the south coast of the Algarve, off Portugal, in water depths from 60 to 800 meters. The special focus was on the areas to the east of Portimão and the west of Sagres/Martinhal transects, close to the famous Martinhal, Boca do Rio and Salgados AD 1755 onshore sedimentary imprints. This part of the coast was heavily affected by tsunami inundation exactly 263 years ago on All Saints Day 1755 following a strong earthquake offshore. Shortly after the earthquake a tsunami hit the Portuguese coastline. It was one of the most consequential and impressive natural hazards ever reported destroying the Portuguese capital and many villages were destroyed along the south Portuguese coast, with the exception of Faro that was sheltered by sandbanks, whereas in Lagos the waves overtopped the city walls. Deposits of the Lisbon 1755 tsunami have been well studied along the southern Portuguese coast, but the impact of backwash, the retreating flood into the sea has not been well understood and studied. To date, very scarce information on backwash deposits is available from other areas, so this is unknown terrain, especially in these water depths. We focus on the following scientific questions: Do we find variations in thickness and sediment composition, distribution and preservation of the tsunami layer? What effects on benthic life after tsunami deposition can be observed? Can we develop a tool for the identification of historic and prehistoric tsunami deposits on the inner shelf? Can we detect predecessor events along the Algarve coast, and obtain information about timing, frequency and magnitude of these natural hazards thus extending the time-window of observation?We collected pre- and post-tsunami deposits (the background sedimentation) along the transects for comparison, e.g. of the benthic life and its resilience. Other proxies such as geochemistry and physical properties are analyzed as well. Radiocarbon and OSL dating methods are used for establishing a geochronological framework and to estimate ages of preceding events identified macroscopically in the sediment cores. Overall, the lithostratigraphic column can be characterized as a silty-dominated sequence, likely reaching the Younger Dryas. More importantly, we detected a gravelly high-energy layer at a depth of approx. 16-25 cm depth in many cores, characterized by an erosive base, shell debris and well-rounded extra-clasts of fluvial origin. A surprising finding was a second medium to coarse sand layer at depths of around 150-180 cm with clear indications of a high-energy depositional environment (e.g. sharp erosional base, mineralogical diversified composition, macrofossil diversity, etc.). Both of the layers are found within cores of the two transects; they are preliminarily interpreted as two events, the upper is regarded as deposits of the 1755 event, whereas the lower dates younger than 4000 yrs BP. [ABSTRACT FROM AUTHOR]

The prevalence of ancient abandoned fluvial landforms in the northern Chilean Atacama Desert is a testament to both the long-term hyperaridity of this setting and its sensitivity to change. Ascertaining what has driven drainage adaptations has the potential to reveal past environmental changes and whether they were localized or regional in extent. However, it is typically unclear whether processes related to climate, tectonics, or both, are the cause of drainage reorganization. Alternatively, an often overlooked driver of topographic change is the breaching of geomorphic thresholds, whereby abrupt erosional or depositional episodes occur without the need for external causes. Instances of geomorphic thresholds include periods of degradation and aggradation experienced by ephemeral streams, or stream piracy events. In this paper we will discuss the incision history of the Tiliviche River (Quebrada Tiliviche) in northern Chile and unravel the contributions made by climate, tectonics and geomorphic thresholds to the evolution of this drainage.Like most of the rivers in northern Chile that reach the Pacific Ocean, the Tiliviche River has its source in the Andes Mountains (Precordillera) and takes a westward route through the hyperarid Central Depression and Coastal Cordillera. Using a cosmogenic nuclide derived chronology for the formation of a flight of river terraces located in the Central Depression we infer a dramatic increase of the incision rate of the Tiliviche River at around 350 ka ago. The fluvial terraces lie downstream of a subtle, fault-related, upward warping of the surrounding pediment surface for tens of km north and south of our sample site. Explanations for a more rapid rate of river incision over the last ca. 350 ka include: an increase in the amount of water available for discharge, possibly related to more precipitation in the Andean headwaters of the basin, or brought about by a stream capture event increasing the upstream catchment area; base-level drop in response to local fault driven uplift; or a base-level fall resulting from the draining of a paleolake downstream or connection of the Tiliviche River to the sea. The likelihood of each of these explanations is considered in greater detail with reference to characteristics of the local faults, the timing of abandonment of adjacent paleochannels and mapping of other Tiliviche River terraces, the dating of which is currently underway. [ABSTRACT FROM AUTHOR]

Remote sensing techniques, namely Unmanned Aerial Vehicle (UAV) photogrammetry and t-LiDAR (terrestrial Light Detection and Ranging), two well-established techniques, were applied for seven years in a mountainous Mediterranean catchment in Greece (Ilioupoli test site, Athens), following a wildfire event in 2015. The goal was to monitor and quantify soil erosion and sedimentation rates with cm accuracy. As the frequency of wildfires in the Mediterranean has increased, this study aims to present a methodological approach for monitoring and quantifying soil erosion and sedimentation rates in post-fire conditions, through high spatial resolution field measurements acquired using a UAV survey and a t-LiDAR (or TLS—Terrestrial Laser Scanning), in combination with georadar profiles (Ground Penetration Radar—GPR) and GNSS. This test site revealed that 40 m3 of sediment was deposited following the first intense autumn rainfall events, a value that was decreased by 50% over the next six months (20 m3). The UAV–SfM technique revealed only 2 m3 of sediment deposition during the 2018–2019 analysis, highlighting the decrease in soil erosion rates three years after the wildfire event. In the following years (2017–2021), erosion and sedimentation decreased further, confirming the theoretical pattern, whereas sedimentation over the first year after the fire was very high and then sharply lessened as vegetation regenerated. The methodology proposed in this research can serve as a valuable guide for achieving high-precision sediment yield deposition measurements based on a detailed analysis of 3D modeling and a point cloud comparison, specifically leveraging the dense data collection facilitated by UAV–SfM and TLS technology. The resulting point clouds effectively replicate the fine details of the topsoil microtopography within the upland dam basin, as highlighted by the profile analysis. Overall, this research clearly demonstrates that after monitoring the upland area in post-fire conditions, the UAV–SfM method and LiDAR cm-scale data offer a realistic assessment of the retention dam's life expectancy and management planning. These observations are especially crucial for assessing the impacts in the wildfire-affected areas, the implementation of mitigation strategies, and the construction and maintenance of retention dams. [ABSTRACT FROM AUTHOR]

The region around the town Albstadt, SW Germany, was struck by four damaging earthquakes with magnitudes greater than five during the last century. Those earthquakes occurred along the Albstadt Shear Zone (ASZ) which is characterized by more or less continuous microseismicity. As there are no surface ruptures visible which may be connected to the fault zone, its characteristics can only be studied by its seismicity. We use the earthquake data of the state earthquake service of Baden-Württemberg from 2011 to 2018 and complement it with additional phase picks beginning 2016 at the AlpArray and StressTransfer seismic networks in the vicinity of the ASZ. This extended dataset is used to determine new minimum 1-D seismic vp and vs velocity models and corresponding station delay times for earthquake relocation. Fault plane solutions are determined for selected events and the direction of the maximum horizontal stress is derived. The minimum 1-D seismic velocity models have a simple and stable layering with increasing velocity with depth in the upper crust. The corresponding station delay times can be well explained by the lateral depth variation of the crystalline basement. The relocated events align north-south with most of the seismic activity between the towns of Tübingen and Albstadt east of the 9° E meridian. The events can be separated into several subclusters which indicate a segmentation of the ASZ. The majority of the 36 determined fault plane solutions features a NNE-SSW strike, but also NNW-SSE striking fault planes are observed. The main fault plane associated with the ASZ is dipping steeply and the rake indicates mainly sinistral strike-slip, but we also find minor components of normal and reverse faulting. The determined direction of the maximum horizontal stress of 147° is in good agreement with prior studies. This result indicates that the stress field in the area of the ASZ is mainly generated by the regional plate driving forces as well as the Alpine topography. [ABSTRACT FROM AUTHOR]

Abstract Bending moment normal faults (BMF) form during outer-arc extension of a folding layer. These faults, observed in contractional and extensional tectonic environments, can represent the only tectonic features potentially available for paleoseismological investigations (i.e., trenching) in order to date the movement of deeper structures. Yet, the reliability of BMF as a paleoseismological feature is debated in terms of its potential to continuously record coseismic deformation and their relationship with progressive flexure. We made use of analogue modeling in order to explore a simple model of progressive orthogonal flexure and the development of BMF. We collected data on mode of BMF inception and growth by analyzing time-series of cross section deformation, measuring dip-parallel BMF displacement profiles, and constructing a three-dimensional model of fault architecture by slicing of the experiment. Our results point to a model of BMF development typical of mechanically constrained faults, where limits on self-similar growth of faults is imposed once a maturity stage of displacement accumulation is attained. The BMF can accumulate displacement until the structure reaches a maturity stage when further slip is inhibited. This could result in an incomplete paleoseismological record of further fold movements. However, this fault stage can be recognized by the D-shaped displacement profile, typical of mature BMF. A simple two-dimensional constant-area balancing model is proposed, allowing us to derive incremental changes in flexuring, given the area of the collapsed sector with BMF and the thickness of the faulted layer. These results support the use of BMF as a paleoseismological proxy for deeper structures. [ABSTRACT FROM AUTHOR]

As part of the annual conference of the German Geological Society - Geological Association (DGGV) in 2023, various personalities were honored. Dr. Victor A. Ramos received the Leopold von Buch plaque for his work in Andean geology. Prof. Dr. Donald B. Dingwell was awarded the Gustav Steinmann Medal for his contributions to volcanology. Prof. Dr. Ralf Littke also received the Gustav Steinmann Medal for his outstanding achievements in the geosciences. Dr. habil. Frank W. Junge was honored with the Serge von Bubnoff Medal, and Dr. Stefanie Tofelde received the Hermann Credner Prize for her research on the dynamics of rivers and their impact on sediment transport. [Extracted from the article]

The Arabian Peninsula is surrounded by seismically highly active plate margins, while the interior seems to be free from destructive earthquakes. We report two historical earthquakes in Qalhat, Oman, >300 km from any plate boundary and provide archaeoseismological analysis of ruined buildings. The first quake hit the city in 1497 AD with an intensity VII at most; the community survived and damage was repaired. The second event caused total devastation (intensity X-XI), sometime between 1580 and 1592. The city never recovered from the latter; it has been a field of ruins ever since. ShakeMap modeling yielded magnitude Mw 5.5 for the first and Mw 6.5–7.0 for the second earthquake. We suggest that the strike-slip Tiwi Fault or the reverse Qalhat Fault caused the first, while the reverse Qalhat Fault might have caused the second earthquake. [ABSTRACT FROM AUTHOR]

Since the publication of Paleoseismology (2nd Edition) in 2009, there has been no comprehensive survey of new trends in Quaternary tectonics. This paper seeks to remedy that situation, by describing the new technologies and interpretations that arose over the past decade. The major technological advances have been in remote sending, e.g., unpiloted aerial vehicles (drones); airborne laser scanning (lidar); terrestrial laser scanning; 3D topographic surveys from Structure-from-Motion; and satellite geodesy such as D-InSAR. Advances have also been made in dating Quaternary deposits, including single-grain luminescence dating (in the laboratory), and portable optically-stimulated luminescence dating (in the field). Geophysical surveys are now a common component of neotectonic investigations, permitting a more formal, 3D integration of subsurface data with surface data. These techniques have lowered the threshold of recognition to smaller and smaller earthquakes, and allowed detection of off-fault deformation such as distributed faulting and folding. We are now collecting so much data that quality control of coseismic field measurements has become an issue, especially when assembling data sets made of old and new data. Soon this data problem will force a reassessment of our time-honored interpretive paradigms, most of which originated in the 1970s and 80s in the early days of neotectonics. [ABSTRACT FROM AUTHOR]

Passive seismic analyses are a key technology for the exploration and monitoring of subsurface reservoirs. Searching for alternative resources in the framework of the energy transition is creating a surge for identifying as many potential sites as possible suitable for geothermal exploitation. The Lower Rhine Embayment, at the western border of North Rhine-Westphalia in Germany, is an extensional system with a very high potential for geothermal exploitation. The area experiences moderate but continuous natural seismicity. Here, we report on a passive seismic dataset recorded with 48 seismic stations centred at and around Eschweiler–Weisweiler (10.14470/MO7576467356, Finger et al., 2022). Background seismic noise levels are high at this site due to high levels of anthropogenic noise and thick unconsolidated sedimentary layers. The final station layout is a compromise between targeted network design and suitably quiet locations. We show that the network design allows for the application of state-of-the-art methods including waveform-based source location methods and ambient-noise velocity imaging methods. [ABSTRACT FROM AUTHOR]

The Kalabagh Fault forms a lateral offset in the Main Frontal Thrust in the Sub-Himalayan area of Pakistan, forming a push-up block within the stepover zone of its segments. Deformed sediments along the frontal part of this push-up block have cross cutting relations with morphotectonic and paleoseismic features. These sediments are dated using luminescence dating methods. The post-infrared infrared stimulated luminescence (post-IR IRSL) of K-feldspar was used for samples representing these sedimentary units. For stratigraphically younger sediments with partially-bleached pIRIR signal, optically stimulated luminescence (OSL) of quartz was applied with the minimum age model (MAM). These ages are used to illustrate the timing of development of the push-up block, the westward diversion of the Indus River and Holocene earthquakes along the Kalabagh Fault (KBF). The deformed sediments from the mountain front at Larkakki are older than those of Khairabad and Ghundi. These age estimates are consistent with the chronological order of the tectonic deformations in the stepover zone of the Kalabagh Fault. Age estimates and correlation of the sedimentary units suggest the emergence of the push-up block in the stepover zone during the past ∼0.5 Ma. Active faulting and development of the ramp along the Kalabagh Fault has diverted the course of the Indus River towards the west at a displacement rate of 12–15 cm/a during last ∼140 ka. Luminescence data indicate Holocene timing for the earthquakes along the Kalabagh Fault, which are diachronous and suggest differential movements along the segments of the fault. The earthquake recurrence interval at Khairabad is 10 ± 2 ka on average. The younger earthquakes at the foreland in the south of the stepover indicate seismically active zone. [ABSTRACT FROM AUTHOR]

This study presents results from two sediment cores collected on the southern Portuguese shelf attempting to, partially, fill the knowledge gap of the offshore record of high-energy events. The results were obtained based on description of cores, microtextural analysis of quartz grains, and foraminiferal taphonomy. The lithostratigraphy corresponds to Late Holocene sedimentation, with interesting intercalations of medium sand rich with bioclastic fragments and erosive basal contact. In terms of microtextures, a high degree of mechanical marks on the grains associated with tsunami deposition was observed and reflects the high-energy hydrodynamic processes. In compositional terms, the higher presence of quartz grains in these units favors the increase of mechanical marks because grain-to-grain contact is more intense. Additionally, the geomorphological setting of the coring sites controlled the degree and type of mechanical microtextures observed. Furthermore, post-depositional changes and characteristics of the original sediment source contribute to explain the occurrence of dissolution in units of GeoB23513-02. The foraminiferal taphonomy displayed a predominance of dissolution alteration in the test surfaces that was more evident in the silty layers. On the other hand, similar to quartz grain microtextural signature, the sandy high-energy units exhibit a slight predominance of physical processes despite the still strong presence of dissolution. The sole presence of foraminifera species from the middle to the outer shelf in some units is an indication that there was little reworking of specimens. This work aims to increase the understanding of dynamics during Holocene high-energy events and to characterize their backwash phases through the different imprints left in the sedimentary offshore record of the Portuguese Algarve shelf. [ABSTRACT FROM AUTHOR]

Passive seismic datasets are a key technology for exploration and monitoring of subsurface reservoirs. Searching for alternative resources in the framework of the energy transition creates a surge for identifying as many potential sites as possible suitable for geothermal exploitation. The Lower Rhine Embayment, at the western border of North Rhine-Westphalia in Germany, is an extensional system with a very high potential for geothermal exploitation. The area experiences moderate but continuous natural seismicity. Here, we report on a passive seismic dataset recorded with 48 seismic stations centred at and around Eschweiler-Weisweiler. Background seismic noise levels are high at this site due to high levels of anthropogenic noise and thick unconsolidated sedimentary layers. The final station layout is a compromise between targeted network design and suitably quiet locations. We show that the network design allows the application of state-of-the-art methods including waveform-based source location methods and ambient noise velocity imaging methods. [ABSTRACT FROM AUTHOR]

Knowledge of tsunami risk and vulnerability is essential to establish a well-adapted Multi Hazard Early Warning System, land-use planning and emergency management. As the tsunami risk for the coastline of Oman is still under discussion and remains enigmatic, various scenarios based on historical tsunamis were created. The suggested inundation and run-up heights were projected onto the modern infrastructural setting of the Muscat Capital Area. Furthermore, possible impacts of the worst-case tsunami event for Muscat are discussed. The approved Papathoma Tsunami Vulnerability Assessment Model was used to model the structural vulnerability of the infrastructure for a 2 m tsunami scenario, depicting the 1945 tsunami and a 5 m tsunami in Muscat. Considering structural vulnerability, the results suggest a minor tsunami risk for the 2 m tsunami scenario as the flooding is mainly confined to beaches and wadis. Especially traditional brick buildings, still predominant in numerous rural suburbs, and a prevalently coast-parallel road network lead to an increased tsunami risk. In contrast, the 5 m tsunami scenario reveals extensively inundated areas and with up to 48% of the buildings flooded, and therefore consequently a significantly higher tsunami risk. We expect up to 60000 damaged buildings and up to 380000 residents directly affected in the Muscat Capital Area, accompanied with a significant loss of life and damage to vital infrastructure. The rapid urbanization processes in the Muscat Capital Area, predominantly in areas along the coast, in combination with infrastructural, demographic and economic growth will additionally increase the tsunami risk and therefore emphasizes the importance of tsunami risk assessment in Oman. [ABSTRACT FROM AUTHOR]

The Lower Rhine Embayment in Central Europe hosts a rift system that has very low deformation rates. The faults in this area have slip rates of less than 0.1 mm yr-1, which does not allow to investigate ongoing tectonic deformation with geodetic techniques, unless they cover very long time spans. Instrumental seismicity does only cover a small fraction of the very long earthquake recurrence intervals of several thousands of years. Palaeoseismological studies are needed to constrain slip rates and the earthquake history of such faults. Destructive earthquakes are rare in the study area, but did occur in historic times. In 1755/1756, a series of strong earthquakes caused significant destruction in the city of Düren (Germany) and the surrounding areas. In this study we document palaeoseismological data from the nearby Rurrand Fault. In contrast to earlier studies on the same fault, we found evidence for a surface rupturing earthquake in the Holocene, and we identified at least one more surface rupturing event. Our study shows that the Rurrand Fault currently accommodates deformation in earthquakes rather than by creeping. The coseismic offsets were determined to be between less than 0.5 m per event.We assign maximum possible magnitudes of Mw 5.9-6.8 for the Rurrand Fault and a slip rate of at least 0.02-0.03 mm yr-1 for the last ∼130-50 kyr. The surface ruptures did not occur at the main fault trace that has a clear morphological expression due to older tectonic motions, but on a younger fault strand in the hanging wall of the main fault. Terrain analyses based on 1 m resolution airborne LiDAR data have been used to image the subtle morphological expression of this young fault zone. Georadar and electric resistivity tomography were applied to image the fault zone at depth and to test if these shallow geophysical methods can be used to identify and trace the fault zone. Georadar failed to produce reliable results, but geoelectrics were successfully applied and allowed us to retrieve slip rate estimates. Our results indicate that the Düren 1755/1756 earthquakes did not produce surface ruptures at the Rurrand Fault, either because they did not rupture the surface at all, or because they occurred at another, neighbouring fault. [ABSTRACT FROM AUTHOR]

The Arabian Sea is regarded as one of the least studied regions in terms of coastal hazards such as tropical cyclones and tsunamis. Parts of the coastline are developing rapidly, especially in Oman. This calls for a proper understanding of the natural processes that act on and affect it. This can be done by investigating the magnitude and impact of past events, in particular on human settlements. By doing this, future risks may not only be scientifically predicted and evaluated, but the damage caused by future events might even be mitigated. Evidence of past extreme wave events is preserved in the onshore stratigraphic record. In addition to this, the coastal zone of Oman is rich in archaeological remains. Presented here are the results of comprehensive mapping and analysis of extreme wave deposits of an archaeological site near Ras al-Hadd, suggesting that the Early Bronze Age site HD-6 was inundated at 4450 cal. BP. An event layer is identified between two settlement phases within the archaeological excavation. A contemporaneous sand bed with a maximum thickness of 0.4 m was mapped in the vicinity of the settlement. Ground penetrating radar surveys allow measurement of the thickness as well as identification of the internal facies architecture of the deposit. A high resolution digital elevation model reveals the coastal geomorphology. It is concluded that the causative event must have been a tsunami that was most likely generated within the Makran Subduction Zone. This interpretation does however, remain tentative at the moment. Archaeological evidence indicates that the site was immediately re-occupied after the event, which attests to a certain resiliences of the Early Bronze Age coastal communities in the region. [ABSTRACT FROM AUTHOR]

We describe two 5–7 km long normal fault scarps (NFSs) occurring atop fault-related anticlines in the coastal ranges of the Dinarides fold-and-thrust belt in southern Montenegro, a region under predominant contraction. Both NFSs show well-exposed, 6–9 m high, striated, and locally polished fault surfaces, cutting uniformly northeastward-dipping limestone beds at high angles and documenting active faulting. Sharply delimited ribbons on free rock faces show different colors, varying karstification, and lichen growth and suggest stepwise footwall exhumation, which is typical of repeated normal faulting during earthquake events. Displacements, surface rupture lengths, and geometries of the outcropping fault planes imply paleoearthquakes with Mw≈6 ± 0.5 and slip rates of ∼ 0.5–1.5 mm yr -1 since the Last Glacial Maximum. This is well in line with (more reliable, higher-resolution) slip rates based on cosmogenic 36 Cl data from the scarps for which modeling suggests 1.5 ± 0.1 mm yr -1 and 6–15 cm slip every 35–100 years during the last ∼ 6 kyr. The total throw on both NFSs – although poorly constrained – is estimated to ∼ 200 m and offsets the basal thrust of a regionally important tectonic unit. The NFSs are incipient extensional structures cutting (and postdating emplacement of) the uppermost Dinaric thrust stacks down to an unknown depth. To explain their existence in a region apparently under pure contraction, we consider two possibilities: (i) syn-convergent NFS development or – less likely – (ii) a hitherto undocumented propagation of extensional tectonics from the hinterland. Interestingly, the position of the extensional features documented here agrees with geodetic data, suggesting that our study area is located broadly at the transition from NE–SW-directed shortening in the northwest to NE–SW-directed extension to the southeast. While the contraction reflects ongoing Adria–Europe convergence taken up along the frontal portions of the Dinarides, the incipient extensional structures might be induced by rollback of the Hellenic slab in the southeast, whose effects on the upper plate appear to be migrating along-strike of the Hellenides towards the northwest. In that sense, the newly found NFSs possibly provide evidence for a kinematic change of a thrust belt segment over time. However, with a significantly higher probability, they can be regarded as second-order features accommodating geometrical changes in the underlying first-order thrust faults to which they are tied genetically. [ABSTRACT FROM AUTHOR]

The Kalabagh Fault Zone in the western Sub-Himalayas is a dextral strike slip fault zone that exhibits a push-up block in the stepover zone of the two fault segments. The inception of the push-up block occurred along the restraining faults that form two morphotectonic bends along the mountain front at Zaluch and in the South of Thathi. The landform was further developed by en-echelon fold and thrust sequence up to Khairabad in the North and Ghundi village in the South. The aseismically moving fault zone has experienced earthquakes during late Quaternary forming surface expressions in the West of the push-up block at Khairabad, Larkakki and Ghundi. The Khairabad and Ghundi sections are the active tectonic fronts of the stepover zone. Displacements caused by these seismic activities has deformed Quaternary sediments creating stream deflections, surface ruptures, pressure ridges, uplifted sediments at the mountain front, foreland ridges and uplifted alluvial fan. Offsets in the late Quaternary sediments indicate the Kalabagh Fault is active and seismic events of M w ≥ 6 has formed these ground effects. Furthermore, stratigraphic correlations of fluvial sediments indicate the Indus River has been flowing in the NS direction along the northern segment of the Kalabagh Fault. Uplift of the push-up block in the Kalabagh Fault Zone and subsequent deposition of the alluvial fans has caused westward diversion of the Indus River. [ABSTRACT FROM AUTHOR]

Abstract: Charlemagne (Charles the Great) placed the centre of his kingdom during Carolingian times in Aachen, Germany (Aquisgrana). This medieval period and his regency are associated with a period of extensive constructions in Aachen, including the Carolingian part of the Aachen cathedral. The cathedral was the first building in Germany to join the UNESCO World Heritage list. The foundations and construction ground of the cathedral were excavated during recent archaeological and geotechnical investigations. The cathedral is founded on pillars and piles in Devonian blue limestone and shale, covered by Pleistocene loess sediments. Remains of Roman buildings, such as thermae, are situated below this part of the cathedral. The pillars are connected by up to 5 m deep foundation walls and are up to 2.4 m thick. Even though information about the construction site is important for the assessment of structural health and remediation measures, it is often rare for old historical buildings. Documentations from construction time concentrate on the construction progress and financial aspects. Detailed descriptions on the foundation ground and techniques are usually not preserved. This information is of relevance for assessment of earthquake related structural damages and site effects on construction. Investigations in the course of remediation measures or archaeological surveys fill this information gap. They provide insights in the ancient foundation techniques and can be used for identifying earthquake related phenomena in the construction site. Furthermore, a direct insight into potential seismic effects associated with the ground and building response on seismic shaking becomes possible. In the case of the Aachen cathedral, typical geotechnical investigation methods including drilling and laboratory tests were applied together with GPR measurements to evaluate the construction ground and evaluate potential seismological effects. [Copyright &y& Elsevier]

Abstract: We analyse the deformation pattern along the south-western margin of the Central European Basin System (CEBS) where Upper Carboniferous–Mesozoic rocks are uplifted due to the Late Cretaceous basin inversion. The geometry of mesoscale faults and associated striae are used to calculate the stress state(s) responsible for the observed deformation. Each reduced stress tensor obtained comprises (i) the directions of the principal stress axes σ 1, σ 2, and σ 3 (σ 1 ≥ σ 2 ≥ σ 3) and (ii) the ratio of principal stress differences R =(σ 2 − σ 3)/(σ 1 − σ 3). We present a stress inversion technique that allows each stress state inherent in a heterogeneous fault population to be identified by integrating the results of the PBT-Method [Turner, F.J., 1953. Nature and dynamic interpretation of deformation lamellae in calcite of three marbles. American Journal of Sciences, 251(4): 276–298; Sperner, B., Ratschbacher, L. and Ott, R., 1993. Fault-striae analysis: a Turbo Pascal program package for graphical presentation and reduced stress tensor calculation. Computers & Geosciences, 19: 1361–1388] and the Multiple Inverse Method [Yamaji, A., 2000. The multiple inverse method; a new technique to separate stresses from heterogeneous fault-slip data. Journal of Structural Geology, 22(4): 441–452]. This comprehensive approach not only facilitates the separation of complex data sets into homogeneous subsets but also guarantees that each stress state derived fulfils both the criteria of low-misfit angles (Wallace–Bott hypothesis) and high shear-to-normal-stress ratios (Mohr–Coulomb criterion). The reliability of our technique is confirmed by the fact that irrespective of (i) the number of fault-slip data from an outcrop, (ii) the number of subsets they represent and (iii) the proportion of newly formed and reactivated faults, we obtain consistent results from outcrops of variously aged rocks. This consistency concerns both calculated stress states as well as locally observed deformation sequences. Such local chronologies are derived from cross-cutting relationships and superimposition of different fault-slip data which individually are assigned to a consistent stress state. A synthesis of results from different locations of the study area argues for the superposition of two main deformation events. Most prominently, the area was affected by a stress state with a horizontal N–S- to NE–SW-directed maximum compression (σ 1) and a low stress ratio which induced reverse and strike-slip faulting. A pure strike-slip regime of E–W- to NW–SE-directed compression with moderate stress ratios is less prevalent and probably younger. The age of the youngest rocks documenting these two phases proves the stress fields to correspond to the polyphase Late Cretaceous–Tertiary basin inversion of the CEBS during post-Cenomanian times. The youngest tectonic imprints detected in the study area correspond to locally appearing extensional stress states with varying directions of σ 3. At many sites, the youngest derived paleostress state coincides with the present-day stress field in terms of the direction of the maximum horizontal stress axis, S Hmax. The only stress state detected which pre-dates the basin inversion corresponds to an extensional regime with an WNW-ESE- to NW–SE-directed σ 3-axis observed only locally in the N–S striking Leine Graben and its prolongation to the North. The fact that the majority of variously aged rocks exhibit only the traces of the latest deformation phases indicates a high degree of fault plane reactivation in the study area. [Copyright &y& Elsevier]

The Dinaric Fault System in western Slovenia, consisting of NW–SE-trending, right-lateral strike-slip faults, accommodates the northward motion of Adria with respect to Eurasia. These active faults show a clear imprint in the morphology, and some of them hosted moderate instrumental earthquakes. However, it is largely unknown if the faults also had strong earthquakes in the late Quaternary. This hampers our understanding of the regional tectonics and the seismic hazard. Geological evidence of co-seismic surface ruptures only exists for one historical event, the 1511 Idrija earthquake with a magnitude of ∼ M 6.8, but the causative fault is still disputed. Here we use geomorphological data, near-surface geophysical surveys, and paleoseismological trenching to study two of these faults: the Predjama Fault and the Idrija Fault. In a paleoseismological trench across the Predjama Fault we found deformation features that may have been caused by an earthquake between 13–0.7 ka, very likely not earlier than 8.4 ka. At the Idrija Fault, a surface-rupturing earthquake happened around 2.5 ka. We show that instrumental and historical seismicity data do not capture the strongest events in this area. [ABSTRACT FROM AUTHOR]

Soil changes, including landslides and erosion, are some of the most prominent post-fire effects in Mediterranean ecosystems. Landslide detection and monitoring play an essential role in mitigation measures. We tested two different methodologies in five burned sites with different characteristics in Central Greece. We compared Unmanned Aerial Vehicles (UAV)-derived highresolution Digital Surface Models and point clouds with terrestrial Light Detection and Ranging (LiDAR)-derived point clouds to reveal new cracks and monitor scarps of pre-existing landslides. New cracks and scarps were revealed at two sites after the wildfire, measuring up to 27 m in length and up to 25 - 5 cm in depth. Pre-existing scarps in both Kechries sites appeared to be active, with additional vertical displacements ranging from 5-15 - 5 cm. In addition, the pre-existing landslide in Magoula expanded by 8%. Due to vegetation regrowth, no changes could be detected in the Agios Stefanos pre-existing landslide. This high-spatial-resolution mapping of slope deformations can be used as landslide precursor, assisting prevention measures. Considering the lack of vegetation after wildfires, UAV photogrammetry has great potential for tracing such early landslide indicators and is more efficient for accurately recording soil changes. [ABSTRACT FROM AUTHOR]

We describe two previously unreported, 5-7 km long normal fault scarps (NFS) occurring atop fault-related anticlines in the coastal ranges of the Dinarides fold-and-thrust belt in southern Montenegro, a region under predominant contraction. Both NFS show well-exposed, 6-9 m high, striated and locally polished fault surfaces in limestones, documenting active faulting during the Holocene. Sharply delimited ribbons on free rock faces show different color, varying karstification and lichen growth and suggest stepwise footwall exhumation, typical of repeated normal faulting earthquake events. Displacements, surface rupture lengths and geometries of the outcropping fault planes imply paleoearthquakes with Mw ~ 6 ± 0.5 and slip rates of c. 0.3-0.5 mm/yr since the Last Glacial Maximum. Slip rates based on cosmogenic 36Cl data from the scarps are significantly higher: modeling suggests 1.5 ± 0.1 mm/yr and 6-15 cm slip every c. 35-100 yrs, commencing c. 6 kyr ago. The total throw on both NFS - although poorly constrained - is estimated to max. 200 m, and offsets the basal thrust of a regionally important tectonic unit. Both NFS are incipient extensional structures that postdate growth of the fault-related anticlines on top of which they occur. Interestingly, the position of the extensional features agrees with recent geodetic data, suggesting that our study area is located exactly at the transition from NE-SW-directed shortening in the northwest to NE-SW-directed extension to the southeast. While the contraction reflects ongoing Adria-Europe convergence taken up along the frontal portions of the Dinarides, the incipient extensional structures might be induced by rollback of the Hellenic slab in the SE, whose effects on the upper plate appear to be migrating along-strike the Hellenides towards the northwest. The newly found NFS provide evidence for a kinematic change of a thrust belt segment over time. Alternatively, the NFS might be regarded as second-order features accommodating changes in dip of the underlying first-order thrust faults to which they are tied genetically. [ABSTRACT FROM AUTHOR]

In southern Iberia, the surroundings of the Strait of Gibraltar are known as a crossroad for population movements, cultural exchanges, and trade from Late Prehistory to modern times. However, questions remain about the impact of this historical development on the environment. The settlement of La Silla del Papa, an important hillfort in southern Andalusia (Cádiz), was occupied during the entire Iron Age, replaced by the coastal town Baelo Claudia during Roman times, and re‐occupied during Early Medieval times. As such, La Silla del Papa and its territory represent an ideal location for long‐term studies on human‐environment interactions. Within the framework of the interdisciplinary project "Archeostraits," geoarchaeological investigations in the surroundings of La Silla del Papa aimed at constraining ecological conditions and human‐environment interactions during the mid‐ and late Holocene and during major human occupation phases. Our results document an early mid‐Holocene marine embayment in the lower floodplain of the Río del Cachón, rapidly turning into a coastal lagoon and later into freshwater‐dominated wetlands. After approximately 2100 BP (c. 150 BC), fluvial and alluvial deposition i600ing a high anthropogenic impact on the local landscape during Roman or post‐Roman times. Palynological results reveal fluctuating agricultural and pastoral activities and distinct periods of landscape opening during the Neolithic and Iron Age. [ABSTRACT FROM AUTHOR]

With a minimum of three reported waves, the 2011 Tohoku-oki tsunami's destructive force caused massive damage along the northern Japanese Aomori coast. At Misawa the coastal control area was inundated up to 550 m inland and sandy sediment remnants can be traced to c. 350 m (c. 61–63% of the maximum inundation) from the shoreline. Linking the discovery of floatable plastic objects within a woody and organic layer to our analytical data lead to the detection of a yet undocumented woody-organic tsunami deposit first appearing on top of the sandy deposit but then reaching even further inland (approx. 69–72% of the max. inundation). By this observation our understanding of the documented part of the tsunami inundation may be improved. As a consequence, sand sheets of historic and paleo-tsunamis represent minimum estimates for the coastal inundation and underestimation may be reduced by addressing the woody and organic fraction of a tsunami's inundation. [ABSTRACT FROM AUTHOR]

The Dinaric Fault System in western Slovenia, consisting of NW-SE trending, right-lateral strike-slip faults, accommodates the northward motion of Adria with respect to Eurasia. These active faults show a clear imprint in the morphology and some of them hosted moderate instrumental earthquakes. However, it is largely unknown if the faults also had strong earthquakes in the Late Quaternary. This hampers our understanding of the regional tectonics and the seismic hazard. Geological evidence of co-seismic surface ruptures only exists for one historical event, the 1511 Idrija Earthquake with a magnitude of ~M6.8, but the causative fault is still disputed. Here we use geomorphological data, near-surface geophysical surveys, and paleoseismological trenching to show that two of these faults, the Predjama Fault and the Idrija Fault ruptured in strong earthquakes in the Holocene. In a paleoseismological trench across the Predjama Fault we found at least one earthquake with a minimum magnitude of MW6.1 that occurred between 13-0.7 ka, very likely not earlier than 8.4 ka. At the Idrija Fault, a surface-rupturing earthquake with a magnitude of at least MW6.1 happened in the last ~2.1 ka. This event could correspond to the 1511 Idrija earthquake. Our results show that the faults rupture in rare, but strong earthquakes, which dominate the seismic moment release. We show that instrumental and historical seismicity data do not capture the strongest events in this area. The fact that many of the NW-SE trending, parallel faults are active implies that the deformation in western Slovenia is distributed, rather than focussed on one major structure. [ABSTRACT FROM AUTHOR]

Organic geochemistry is commonly used in environmental studies. In tsunami research, however, its applications are in their infancy and it is still rarely used. We present results for two types of organic geochemical markers, biomarkers and anthropogenic markers, present in deposits left by 2011 Tohoku-oki tsunami on the Sendai Plain, Japan. As the tsunami inundated the coastal lowland up to 4.85 km inland, sediments from various sources were eroded, transported and deposited. This led to the distribution of biomarkers from different sources across the Sendai Plain creating a unique geochemical signature in the tsunami deposits. The tsunami also caused destruction along the Sendai coastline, leading to the release of large quantities of environmental pollutants (e.g., fossil fuels, tarmac, pesticides, plastics, etc.) that were distributed across the inundated area. These anthropogenic markers, represented by three main compound groups (polycyclic aromatic hydrocarbons, pesticides, and halogenated compounds), were preserved in tsunami deposits (at least until 2013, prior to land clearing). Their concentrations differed significantly from the pre- and post-tsunami background contamination levels. Organic proxy concentrations can differ for sand and mud deposits due to various factors (e.g., preservation, dilution, microbial alteration). However, it can be concluded that anthropogenic markers and biomarkers have the potential to be a valuable proxy for future studies of recent tsunami deposits because of their high source specificity and relatively good preservation potential providing information about sediment sources and transport pathways (e.g., marine source, evidence of backwash). • Study testing the application of anthropogenic markers and biomarkers for identification of tsunami deposits. • Organic-geochemical investigation of 2011 Tohoku-oki tsunami deposits from the Sendai Plain, Japan. • Distinct differentiation of tsunami deposits geochemical signature from pre- and post-tsunami deposits. • Identification of compound groups (i.a., polycyclic aromatic hydrocarbons, n -alkanes, pesticides, halogenated compounds). • Verification of prior research results from the Sendai Plain with results from organic-geochemical analysis. [ABSTRACT FROM AUTHOR]

The 100 000 m 2 wave-cut pavement in the Bristol Channel near Lilstock, UK, is a world-class outcrop, perfectly exposing a very large fracture network in several thin limestone layers. We present an analysis based on manual interpretation of fracture generations in selected domains and compare it with automated fracture tracing. Our dataset of high-resolution aerial photographs of the complete outcrop was acquired by an unmanned aerial vehicle, using a survey altitude optimized to resolve all fractures. We map fractures and identify fracture generations based on abutting and overprinting criteria, and we present the fracture networks of five selected representative domains. Each domain is also mapped automatically using ridge detection based on the complex shearlet transform method. The automatic fracture detection technique provides results close to the manually traced fracture networks in shorter time but with a bias towards closely spaced Y over X nodes. The assignment of fractures into generations cannot yet be done automatically, because the fracture traces extracted by the automatic method are segmented at the nodes, unlike the manual interpretation in which fractures are traced as a path from fracture tip to fracture tip and consist of several connected segments. This segmentation makes an interpretation of relative age impossible, because the identification of correct abutting relationships requires the investigation of the complete fracture trace by following a clearly defined set of rules. Generations 1 and 2 are long fractures that traverse all domains. Generation 3 is only present in the southwestern domains. Generation 4 follows an ENE–WSW striking trend, is suborthogonal to generations 1 and 2, and abuts on them and generation 3, if present. Generations 5 is the youngest fracture set with a range of orientations, creating polygonal patterns by abutting at all other fracture generations. Our mapping results show that the northeastern domains only contain four fracture generations; thus, the five generations of the outcrop identified in the southwestern domains are either not all present in each of the five domains or vary locally in their geometry, preventing the interpreter from linking the fractures to their respective generation over several spatially separate mapping domains. Fracture intensities differ between domains where the lowest is in the NE with 7.3 m -1 and the highest is in the SW with 10 m -1 , coinciding with different fracture orientations and distributions of abutting relationships. Each domain has slightly different fracture network characteristics, and greater connectivity occurs where the development of later shorter fractures is not affected by the stress shadowing of pre-existing longer fractures. [ABSTRACT FROM AUTHOR]

The 100,000 m² wave-cut pavement in the Bristol Channel near Lilstock, UK, is a world-class outcrop, perfectly exposing a very large fracture network in several thin limestone layers. We present an analysis based on manual interpretation of fracture generations in selected domains and compare this with automated fracture tracing. Our dataset of high-resolution aerial photographs of the complete outcrop was acquired by unmanned aerial vehicle, using a survey altitude optimized to resolve all fractures. We map fractures and identify fracture generations based on abutting and overprinting criteria and present the fracture networks of five selected representative domains. Each domain is also mapped automatically using ridge detection based on the complex shearlet transform method. The automatic fracture detection technique provides results close to the manually mapped fracture networks, however, with a bias towards closely spaced Y over X nodes. The assignment of fractures into generations cannot be done automatically yet. Generations one and two are long fractures that traverse our domains. Generation three is only present in the southwestern domains. Generation four follows an ENE-WSW striking trend, is sub-orthogonal to generations one and two and abuts on them and generation 3 if present. Generations five is the youngest fracture set with diffuse orientation, creating polygonal patterns by abutting on all older fracture generations. Our mapping results show that the northeastern domains only contain four fracture generations, thus the five generations of the outcrop identified in the southwestern domains are either not all present in each of the five domains or vary locally in their geometry, preventing the interpreter to link the fractures to their respective generation over several spatially separate mapping domains. The domains have different P21 fracture intensities which is lowest in the NE with 7.31 m/m² and highest in the SW with 10.01 m/m², coinciding with different fracture orientations, and distributions of abutting relationships. Each domain has slightly different fracture network characteristics. The network analysis shows that connectivity increases, depending on the evolving fracture generations. [ABSTRACT FROM AUTHOR]

Far‐field tsunami deposits observed in the Kahana Valley, O'ahu, Hawai'i (USA), were investigated for their organic‐geochemical content. During short high‐energy events, (tsunamis and storms) organic and chemical components are transported with sediment from marine to terrestrial areas. This study investigates the use of anthropogenic based organic geochemical compounds (such as polycyclic aromatic hydrocarbons, pesticides and organochlorides) as a means to identify tsunami deposits. Samples were processed by solid–liquid extraction and analyzed using gas chromatography–mass spectrometry. A total of 21 anthropogenic marker compounds were identified, of which 11 compounds were selected for detailed analysis. Although the tsunami deposits pre‐date industrial activity in Hawai'i by several hundred years, distinct changes were found in the concentrations of anthropogenic marker compounds between sandy tsunami deposits and the surrounding mud/peat layers, which may help in identifying tsunami deposits within cores. As expected, low overall concentrations of anthropogenic markers and pollutants were observed due to the lack of industrial input‐sources and little anthropogenic environmental impact at the study site. This geochemical characterization of tsunami deposits shows that anthropogenic markers have significant potential as another high‐resolution, multi‐proxy method for identifying tsunamis in the sedimentary record. [ABSTRACT FROM AUTHOR]

The western Peloponnese was repeatedly hit by major tsunami impacts during historical times as reported by historical accounts and recorded in earthquake and tsunami catalogues. Geological signatures of past tsunami impacts have also been found in many coastal geological archives. During the past years, abundant geomorphological and sedimentary evidence of repeated Holocene tsunami landfall was found between Cape Katakolo and the city of Kyparissia. Moreover, neotectonic studies revealed strong crust uplift along regional faults with amounts of uplift between 13 m and 30 m since the mid‐Holocene. This study focuses on the potential of direct push in situ sensing techniques to detect tsunami sediments along the Gulf of Kyparissia. Direct push measurements were conducted on the landward shores of the Kaiafa Lagoon and the former Mouria Lagoon from which sedimentary and microfaunal evidence for tsunami landfall are already known. Direct push methods helped to decipher in situ high‐resolution stratigraphic records of allochthonous sand sheets that are used to document different kinds of sedimentological and geomorphological characteristics of high‐energy inundation, such as abrupt increases in grain size, integration of muddy rip‐up clasts and fining upward sequences which are representative of different tsunami inundation pulses. These investigations were completed by sediment coring as a base for local calibration of geophysical direct push parameters. Surface‐based electrical resistivity tomography and seismic data with highly resolved vertical direct push datasets and sediment core data were all coupled in order to improve the quality of the geophysical models. Details of this methodological approach, new in palaeotsunami research, are presented and discussed, especially with respect to the question of how the obtained results may help to facilitate tracing tsunami signatures in the sedimentary record and deciphering geomorphological characteristics of past tsunami inundation. Using direct push techniques and based on sedimentary data, sedimentary signatures of two young tsunami impacts that hit the Kaiafa Lagoon were detected. Radiocarbon age control allowed the identification of these tsunami layers as candidates for the ad 551 and ad 1303 earthquake and tsunami events. For these events, there is reliable historical data on major damage on infrastructure in western Greece and on the Peloponnese. At the former Mouria Lagoon, corroborating tsunami traces were found; however, in this case it is difficult to decide whether these signatures were caused by the ad 551 or the ad 1303 event. [ABSTRACT FROM AUTHOR]

Lake Medina is a small, shallow and endorheic salt lake sensitive to climate variation in south-western Spain, close to Cádiz in western Andalusia. It is located in an evaporitic and karstic environment, and a saline lake affected by highly seasonal precipitation and evaporation. Geochemical and mineralogical data of core CO1313 combined with a robust age model show variation that contributes to the understanding of palaeoenvironmental and palaeoclimatic change. This study shows a pollen record that has been conducted on core CO1313, together with charcoal and non-pollen palynomorph analyses. The environmental and climatological history reconstruction of Lake Medina starts in early Holocene times (at 9.5 cal. ka BP) and shows intensified pasture and land use during middle-Holocene times as well as the 8.2 and 4.2 cal. ka BP abrupt climate events. Oxidation of plant remnants and resulting non-preservation at certain times reinforces the hypothesis of intense climate effects on vegetation during the 4.2 cal. ka BP climate event. Yet, oxidation of plant residues during other episodes shows other periods that were also affected by reduced precipitation. From around 2 cal. ka BP onwards, a recent trend towards aridification and enforced seasonality was detected. [ABSTRACT FROM AUTHOR]