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A quarter of a century ago, during cartographic works using then-known field methods for measuring structural features, on the boundary of the Sudetic and Fore-Sudetic blocks, new phenomena were recognised; these were interpreted to be tectonic in nature and the result of left-lateral strike-slip movement in the subsurface. Grabens, half-grabens, shear zones and seismites in the gold-bearing sands and gravels that form the slopes of the valley of the River Kaczawa, are estimated to be of Pliocene and early Pleistocene age, having been interpreted as deposits of the pre-Kaczawa alluvial fan system. The natural exposures documented 25 years age have now all disappeared. In 2022, these levels became exposed again as a result of renewed gravel exploitation and phenomena described in the past reappeared. Field measurements were made again, this time using modern data-recording techniques, such as photogrammetry and terrestrial laser scanning. This work has enabled a comparison of field measurement methods with those obtained from the point clouds data. The results were found to be highly consistent. At the same time, precise reconstructions of the structures and their connection to the geodetic reference system make it possible to supplement previous geokinematic interpretations for this segment of the Sudetic Marginal Fault Zone (SMFZ). A formerly postulated left-lateral strike-slip regime in this zone was confirmed during the period of formation of the pre-Kaczawa alluvial fan deposits, but also probable is a kinematic inversion that must have occurred during, or just after, the early Pleistocene.

Structural and geophysical indicators of neotectonics in the area of the continental margin of Côte d'Ivoire are represented in three interacting zones: oceanic, continental and transitional. Together with the time-varying gravitational field, they form a system in which neotectonic processes are enhanced due to their equatorial position. Seismicity is represented by dense clusters of events in the areas of junction of the Strakhov, Sao Paulo and Romansh oceanic transform faults with the continent and their overland continuation. Seismicity and gravity variations show the relationship of deep density changes to stress discharge in the area and the effect of volumetric forces on lithospheric blocks. Free air and isostasy anomalies along the shelf are segmented by the effects of vertical motions. Pull-apart depressions near the passive parts of transform faults indicate basement deformations in the interfault blocks and activation of shear displacements of dextral kinematics near the bend of the passive parts of the faults to the northeast from main oceanic azimuth. Segments with isostasy maxima on the shelf correspond to areas with coarser grain size granulometric composition, indicating leaching of fine sedimentary fraction from the bottom material.

ABSTRACTThe Shillong Plateau is the only elevated topography in the Himalayan foreland bounded and crisscrossed by several prominent faults and shear zones. The plateau is situated in a complex tectonic compressional set up, owing to which the fault systems both at the periphery and within tend to be neotectonically active. Due to the elevation difference of the plateau with the Brahmaputra and Meghna River valleys flanking it, coupled with the impervious lithologies present, an intricate network of drainage system has developed in the plateau. In this paper, morphometric and structural analyses of four selected drainage basins from the east-central part of Shillong Plateau have been carried out to comprehend the effects of neotectonic reactivation of fault systems and associated basin tilting which in turn controls the development of drainage pattern. This has led to the understanding of the effects of the ever-evolving fluvial landforms on the anthroposphere in this part of Indian sub-continent, where the agrarian-economy is completely dependent on the intricate fluvial systems.

Abstract The Quadrilátero Ferrífero (QF) is a globally known region for its world-class metallic deposits. Although its Precambrian units have been vastly studied since the 1960s due to economic importance, the Cenozoic geological record represents an upcoming subject of interest. The occurrence of Cenozoic sedimentary deposits has been noticed since the end of the 19th century, but most of them are not yet fully characterized. This paper brings a complete description, mapping, 3D modeling, and simulations of the sedimentary deposit named Bandeira Basin, Serra do Tamanduá, QF. Based on field data, such as mapping and drill core database analysis, three drill cores were selected for further investigation and detailed description. The Bandeira Basin can be characterized and subdivided into three units: Unit A: found only in the southeast area and shows exclusively sediments from the Nova Lima Group; Unit B: intermediate unit that occurs in central and southeast areas, with Rio das Velhas Supergroup as a possible source of the sedimentary material; and Unit C: occurs at the top, and it is essentially colluvial deposits from Minas Supergroup units. The contacts between units are abrupt or erosive, recording successive deposition stages. The basin is thicker on its central and southwest ends and thinner on the east and north, where part of the basement outcrops. Cenozoic tectonic events were probably active in this area, controlling the sedimentary processes, with the NW-SE and NE-SW lineaments reactivated, triggering sediment deposition and migration to the deepest spot of the basin. These sediments were 3D modeled in Leapfrog Geo, the visualization of any given region of interest, in the modeled scale. This methodology allowed an assertive characterization of sedimentary filling and could be applied to other basins. This comprehension is important because these sediments are used indirectly or directly in civil projects.

Abstract On February 6, 2023, two earthquakes shook the southern and central Türkiye causing significant loss of human life and devastating many cities. These are related to the active East Anatolian Fault (EAF). In this study, the digital image correlation (DIC) technique is applied to map the coseismic displacements. For that, a pair of scenes from the Sentinel-2 satellite acquired before and after the seismic events was used. The results showed that the methodological approach can be effectively used to map and monitor large-scale geological phenomena and can assist in seismic risk assessment.

Caves serve as time capsules, preserving significant markers of tectonic activity and offering insights into geological history. Fault geometries and past activations found in caves can be correlated with known deformational events in the broader area, temporally delimiting the speleogenesis. More specifically, cave passage formation is suggested to be affected by the regional stress-field. The Asprorema Cave in Northern Greece is a typical example of a fracture guided cave, with passage geometry influenced by relative sidewall movements, revealing these discontinuities as faults. This study constructs the timeframe and conceptual model of speleogenesis in relation to tectonic events, geomorphological evolution and hydrological zones, and verifies its relation to the stress-field. Active tectonics, mineralogy and cave geomorphology are investigated. Results suggest syntectonic speleogenesis under phreatic and epiphreatic conditions. The absence of corrosion on fault slip surfaces implies recent activations post cave’s shift to the vadose zone. Structural analysis identifies three main neotectonic phases: NNW-SSE striking faults (oldest group of structures), NE-SW striking faults with dextral strike-slip movement (post-middle Miocene), and NE-SW striking normal faults indicating extensional stress-regime (Quartenary). The last two phases affect cave passage shape causing wall displacement, highlighting passage formation along discontinuities perpendicular to the horizontal minimum stress axis.

Active faults are generally defined as faults that have moved in the past and will continue to be active in the future. They are expected to cause deformation and potential disasters if they are localized close to human activities. The definition and classification of active faults are important bases for evaluating the risk. This paper summarizes and compares the history, status, and progress of their definition and classification schemes used in representative countries and regions, as well as in some relevant standards, in active fault mapping, in the construction of spatial databases, and in some other aspects. It is concluded that the current geodynamic setting, existing technical means, geological operability, application purpose, and social acceptability of active faulting hazard in a specific area comprehensively determine the selection of the definition and classification. The key parameter in defining active faults is the time limit. It usually involves four time scales, i.e., Neotectonic (post-Neogene), Quaternary, Late Quaternary, and Holocene. The definition using a short time scale, such as Late Quaternary and Holocene, is usually suitable for the plate boundary zone, which has a high strain rate, but active faults in the intraplate deformation region and stable continental region should be defined with a long time scale, such as the Quaternary and Neotectonics. In addition, the magnitude standard can determine the activity intensity of active faults, which most generally includes three classes, namely, M ≥ 5.0 damaging earthquakes, M ≥ 6.0 strong earthquakes, and M ≥ 6.5 earthquakes that may produce surface displacement or deformation. The M ≥ 5.0 earthquake is generally applicable to regional earthquake prevention and risk mitigation in many countries or regions, but the M ≥ 6.5 earthquake magnitude benchmark is generally used as the standard in rules or regulations regarding active fault avoidance. The most common classification schemes in many countries or regions are based on fault activity, which is reflected mainly by the fault slip rate and fault recurrence interval (FRI), as well as by the last activation time. However, when determining the specific quantitative parameters of the different activity levels of faults, it is necessary to comprehensively consider the differences in activity and ages of the faults in the study region, as well as the amount and validity of existing data for the purpose of classifying different active levels of faults effectively.

In tectonically active areas, such as the Italian peninsula, studying the faults responsible for strong earthquakes is often challenging, especially when the earthquakes occurred in historical times. In such cases, geoscientists need to integrate all the available information from historical reports, surface geology, and geophysics to constrain the faults responsible for the earthquakes from a seismotectonic point of view. In this paper, we update and review, according to the EMS-98 scale, the macroseismic fields of the five main events of the 1783 Calabria sequence (5, 6, and 7 February, 1 and 28 March, Mw 5.9 to 7.1), two other destructive events within the same epicentral area of the 1783 sequence (1791, Mw 6.1 and 1894, Mw 6.1), plus the Messina Strait 1908 earthquake (Mw 7.1). For the 1783 seismic sequence, we also elaborate an updated and new catalog of coseismic effects. The new macroseismic fields were analyzed using a series of MATLAB algorithms to identify (1) the unitarity of the field or its partitioning in sub-sources and (2) the field and sub-fields' main elongation. A collection of earthquake scale laws from literature was used to compute the average source parameters (length, width, and area) with their range of variability, and an elliptical map-view representation of the source geometry was calculated and made available. The analyses of such data allow us to speculate on the earthquakes/faults association, as well as propose new interpretations and reconstruct the space–time evolution of the significant southern Calabria seismic sequences in the last five centuries. [ABSTRACT FROM AUTHOR]

Within Eastern Ukraine, in the course of previous studies, neotectonic movements were established, caused by both salt tectonics and Attic (post-Miocene - pre-Pliocene) thrust dislocations of northeastern vergence. They are partially displayed in modern relief. The aim of the study was to reveal the structural results of the interaction of post-Pliocene fold-thrust deformations and modern salt tectonics of Eastern Ukraine. Research methodology. The base of the Cenozoic deposits of Eastern Ukraine was chosen as an indicator surface reflecting both those and other movements. Its initial orientation is horizontal. Deviations from the horizontal reflect the direction and amplitude of deformations. The morphology of this surface was depicted by isolines with a vertical step of 20 m. To build a map of the supporting surface, state geological maps and data from more than 2,100 wells drilled in this area were used. Research results. A map of the shape of the Cenozoic base in tectonic blocks between the Attic thrusts and beyond their development has been constructed. Uplifts of this surface, which are not associated with thrust movements, have been revealed. The dimensions of such uplifts are 8÷30 × 6÷15 km with vertical amplitude of 40 - 100 m or more. The uplifts are usually contoured by ring or arc compensation troughs a few kilometers wide and 20-100 m deep. Some of these uplifts are associated with the known salt domes of the area. Other uplifts do not contain such domes. It is possible that they formed over salt "pillows", which did not have enough salt reserves to form salt diapirs. The area of distribution of such uplifts approximately corresponds to the area of distribution of Devonian salt deposits at a depth of 5-10 km or more. Scientific novelty. Neotectonic uplifts were discovered, similar in shape and size to those caused by salt tectonics, but located outside the areas of distribution of known salt-bearing strata. It is hypothesized that this is related to the older Hercynian overthrusts. The uplifts are located above the hanging blocks of the Hercynian overthrusts in the north and south of the study area. These thrusts were formed on the northern and southern sides of the former Dnieper-Donetsk depression during its destruction by the Hercynian folding. It is possible that the nappes over thrusts the Devonian salt-bearing deposits with metamorphic rocks of the crystalline basement. The decrease in the level of the World Ocean in the Quaternary period further increased the lithostatic load on the salt-bearing strata. This activated the isostatic upwelling of salt and the formation of gently sloping neotectonic uplifts. Practical significance. These results clarify the geological structure of the territory and make it possible to expand the area of hydrocarbon prospecting.

Hypsometric integral (HI) has been widely used in Geomorphology study as an index to depict the recent and active structures for its sensitivity to the influence of tectonic and different lithology. The traditional methods to study HI often use drainage basins, this may be dependent on basin geometry and drainage area. To avoid this influence, HIs using two digital elevation models of 30 and 90 m of pixels resolution were calculated in Bailongjiang basin. The relations between relief amplitude, mean elevation and HI are also analysed in different analytical window. Meanwhile, spatial pattern analysis using Global Moran's index and Getis-Ord Gi* index was applied to measure the spatial autocorrelation of HI and the distribution of hot spots. It can be concluded that spatial distributions of HI do not show clear spatial patterns and correlation with mean elevation and relief amplitude. HI are independent of the resolution of DEM and lithology but are scale influenced. The hot spots define the upliftment of the region and active faults in the upstream of Bailongjiang basin, the cold spots define tectonic inactivity or subsidence in the downstream of Bailongjiang and some river valley regions. [ABSTRACT FROM AUTHOR]

This paper presents new data on Oligocene–Quaternary deposits, recent (Neogene–Quaternary) structures, and active faults of the northern side of the Ubsunur Basin at its boundary with the Tannu-Ola Ridge, based on structural interpretation of remote sensing (RSD) and field data (2020–2021), including trenching of active faults. Two parageneses of faults of different geological natures and structural and relief-forming significance were identified in the north of the Ubsunur Basin. The first paragenesis presented by the covered North Ubsunur thrust and related deformations that developed during Neogene–Quaternary and which formed the boundary of the depression and the mountain uplift. The second paragenesis includes the South Tannuol and Erzin-Agardag faults, which cut structures of the first paragenesis; these faults were being active in the Late Pleistocene and Holocene. [ABSTRACT FROM AUTHOR]

This paper aims to present a new neotectonic perspective concordant with the seismic activities in Turkey and surrounding regions. The neotectonic structures have been re-evaluated mainly by using focal mechanism solutions and high-resolution satellite (Google Earth) images. The Southeast Anatolian Wedge explains thrust/blind thrust and asymmetrical folding relationship in SE Turkey, Syria, and Northern Iraq. The neotectonic structures of the Turkish-Iranian Plateau are enlightened by the rhomboidal cell model which creates a base to determine multiple intersection points between the region-wide left- and right-lateral shear zones. The releasing stepover between the North Anatolian Fault Zone and Southeast Anatolian-Zagros Fault Zone plus their connections with the Northeast Anatolian Fault Zone and the East Anatolian Fault Zone are described in a more meaningful way with the Anatolian Diagonal concept. It also clarifies the role of left-lateral shear zone in the west-southwest movement of Anatolian plate and its relationship with the Aegean and Cyprus arcs. A neotectonic region under the influence of NW-SE contraction is determined between the North Anatolian, Eskişehir, and Kırıkkale-Erbaa fault zones in which the Elmadağ-Eldivan and Abdüsselam pinched crustal wedges and the Beypazarı Blind Thrust Zone are developed. A new route for the southern branch of the North Anatolian Fault Zone is determined between Bolu and Değirmenlik (Milos) Island in the Aegean Sea via Mudurnu, Bursa, Balıkesir, and İzmir. All main neotectonic structures mentioned in this paper are evaluated by the elastic dislocation modelling and new neotectonic provinces are suggested.

The investigation of deformations in Quaternary deposits holds primary importance in understanding recent geological history and natural hazards in highly populated areas, such as the Po Plain. While civil excavations and trenches possess the potential to be pivotal in identifying and characterizing these deformations, they often remain underused due to the stringent regulation framework and timetables governing civil construction works. In this study, we demonstrate how digital photogrammetry and digital outcrop modelling (DOM) are useful techniques for obtaining a permanent digital representation of a trench situated in Castelletto Ticino (Po Plain–Southern Alps transition). This trench exhibits Holocene deformational structures: (i) an overall tilting of sedimentary deposits towards the SW; (ii) folds with a NE–SW trend; (iii) slumping and other soft-sediment deformations structures; and (iv) reverse faults with NE–SW and NW–SE directions. Using radiocarbon and archeological dating, we are able to confidently constrain the age of these deformations to between 8760 and 400 years BC, suggesting recent tectonic activity related to buried thrust faults.

The basic questions of the methodology of geological and geomorphological study (ore geomorphology, morphostructural analysis, morphotectonics, neotectonics) of ore-bearing territories are considered. The concepts of "geomorphologic systems organization element" as the smallest particle of matter preserving the structure and properties of a mineral, as well as "objectives", "objects" and "subjects" of morphostructural and morphotectonic studies for solving problems of metallogeny have been formulated. In areas with complex geological structure, it is recommended to carry out complex of morphostructural and morphotectonic works with repeated solution of direct and inverse problems: relief and geological environment, geological environment relief. This will make it possible to establish the totality of available deterministic and chronological relations between landforms and structural elements of the lithosphere. Along with the solution of traditional problems of ore geomorphology, it is proposed to use the developed original complex of morphostructural and morphotectonic studies.

The nrotectonic structure of the Kerch-Taman folded zone, the southern deformed part of the Azov-Kuban piedmont trough, has a number of structural features and a history of deformation development. The authors divide the zone into five transverse segments, differing in the age of the main phase of folding. In the central Taman segment, folding is still going on, while in the framing segments, the main phases of folding took place in the Pliocene. In the peripheral segments, the main phase of folding is older - Early-Middle Miocene. The boundaries of the Kerch-Taman zone, as well as its youngest, the Taman segment, coincide with the transverse fault (fault-flexure) zones. It is shown that the southern frame of the Kerch-Taman folded zone is the continuation of the structures of the Crimean Mountains and the Northwestern Caucasus. The correlation of mud volcanism manifestations with tectonic elements of the Taman segment is noted to be ambiguous.

This investigation deals with the delineation of neotectonics and its connection to the regional surface deformation in the Katwaz region (KR) located in the north of Quetta along the Pakistan-Afghan border. It consists of rocks dominated by silicates and carbonates, were uplifted due to regional tectonics. In this study, SRTM DEM (90m spatial resolution) based Surface Dynamics (SDMs) of KR is analyzed to investigate the Isobase level (IBL), Relative relief (RR), Topographic surface roughness (TSR) and topographic Slope (TS) map to constrain the active surface deformation due to regional neotectonics. It gives complete information regarding the lithology based erosional margins and demarcation of neotectonic scarps and established the relationship between Strahler order streams and neotectonic settings in an actively deformed KR. This study aims to delineate margins for geomorphological variations and to find the effects of neotectonics. Another purpose is to examine the geomorphic parameters and to map active tectonics development due to transform sinistral movement of the Chaman Fault system (CFS) in the context of the ongoing collision of India-Eurasia. The resultant and generated surface dynamic maps (SDMs) were due to neotectonic developments, progressions and orientations along with CFS and Suleman fold, and thrust belts (SFTBs). The results obtained revealed that IBL values are higher in the NNE, SSW, and central parts along with the CFS, and partially in the NW corner of the KR due to uplifted SFTBs. The active tectonic nature of SFTBs and TSR values are lower in the central and northern parts of KR. The TSR values are higher along SFTBs and CFS due to greater vertical dissection between these two active faults system. The DEM based SDMs are time-efficient and cost-effective for easy identification and delineation of neotectonically active zones using remote sensing and GIS techniques.

On the north side of the Hexi Corridor, two active faults, which belong to two different fault systems, have been discovered on the southern margin of Beishan, namely the Jiujing-Bantan fault and the Ebomiao fault. The NE-trending (40°~50°) Jiujing-Bantan fault with a NW-trending dip angle of 60°~70° is ~28 km long and ~55 km away from Yumen City. It consists of 4 branches and presents a complex Y-shaped distribution, controlling the development of the two late Pleistocene basins on its west side. The nearly EW-trending Ebomiao fault with a NW-trending dip angle of 60°~80° is ~18 km long and ~50 km away from Jinta County. Base on results from the satellite image interpretation, offset geomorphological survey, trench excavation and optical luminescence dating, we discovered a series of ridges, gullies and terraces offset by the Jiujing-Bantan fault which has been active since ~20 ka ago mostly with normal left-lateral strike-slips. The northward thrusting of the Ebomiao fault formed a clear linear scarp and offset the gullies with left-lateral strike-slips. This fault has been active since ~30 ka ago, mainly with reverse left-lateral strike-slips. The neotectonic activities of these two faults evidences that the long-range strain transmission from the northern margin of the Tibetan Plateau has entered into the southern margin of the Beishan orogenic belt since the late Cenozoic.

This research is focused on the dolines of Dobrá Voda Karst, which is situated in the Brezovské Karpaty Mts. (northeastern part of the Malé Karpaty Mts) near the villages of Chtelnica and Dobrá Voda. 263 dolines were identified here and measured in the field, which is presumably the final count. The measured parameters of the dolines were used for morphometric analyses, as well as for finding out the relationships with the geology of the area. The karst is formed in Triassic carbonates of the Považie and Dobrá Voda nappes of the Hronic Unit. Dolines were identified in Neogene basal carbonatic conglomerates (Dobrá Voda Formation) as well. The area of karst rocks is approximately 87.2 km2. Dolines often tend to be formed in lines with tectonical or lithological predisposition. The most significant lines in the Dobrá Voda Karst are Hlboký Dol, Chtelnické Uhliská, and Cínovec. The origin of dolines can be assumed to the Quaternary Period and related to neotectonics, the development of the relief, and the formation of the river network. This is also confirmed by the trends of the maximum axes of the extension of dolines in the direction N-S, NE-SW and WNW-ESE, which partially correspond to the regional faults. New faults (Hlboký Dol, Cínovec, Bzová) were also identified on the basis of dolines in the lines. [ABSTRACT FROM AUTHOR]

The research area is located on the boundary between two Paleozoic structural units: the Radom–Kraśnik Block and the Mazovian–Lublin Basin in the southeastern Poland. The tectonic structures are separated by the Ursynów–Kazimierz Dolny fault zone. The digital terrain model obtained by the ALS (Airborne Laser Scanning) method was used. Classification and filtration of an elevation point cloud were performed. Then, from the elevation points representing only surfaces, a digital terrain model was generated. The model was used to visually interpret the course of topolineaments and their automatic extraction from DTM. Two topolineament systems, trending NE–SW and NW–SE, were interpreted. Using the kernel density algorithm, topolineament density models were generated. Using the Empirical Bayesian Kriging, a thickness model of quaternary deposits was generated. A relationship was observed between the course of topolineaments and the distribution and thickness of Quaternary formations. The topolineaments were compared with fault directions marked on tectonic maps of the Paleozoic and Mesozoic. Data validation showed consistency between topolineaments and tectonic faults. The obtained results are encouraging for further research.

The Campos do Jordão Plateau, situated in the Serra da Mantiqueira – western flank of the Continental Rift of Southeastern Brazil, presents several morphological features that are indicative of neotectonic activity. This paper presents a morphotectonic map of the southeastern front of the plateau (scale 1:25,000), based on detailed photointerpretation, with structural data obtained during field surveys and also supported by morphometric analysis. The map illustrates morphotectonic features (triangular and trapezoidal facets, rectilinear escarpments, low drainage divides, shutter ridges and drainage captures) and their relationship with brittle structures and lithotypes. Triangular and trapezoidal facets and rectilinear escarpments are commonly associated with normal faults, whereas low divides and shutter ridges are associated with strike-slip ones. The map provides insights into the neotectonic activity and its influence on the landforms in southeast Brazil.

Using ground penetrating radar (GPR) we investigate the near surface (~0–10 m depth) geophysical structure of neotectonic fault-propagation folds and thrust faults in south-central Australia in varying stages of fold and fault growth. Variations in neotectonic fold scarp heights are interpreted to reflect variations in accumulated slip on the underlying reverse faults. Fold scarps on the Nullarbor and Roe Plains are characterized by broad, asymmetric morphologies with vertical displacements of ~5 to ~40 m distributed over 1 to 2 km widths (~0.5 to ~4 m per 100 m). Within increasing scarp height there is an increase in the frequency and spatial density of strong reflector packages in the hanging wall that are attributed to material contrasts imposed by co-seismic fracturing and associated lithological and weathering variations. No evidence for discrete faulting is found at scarp heights up to 40 m (maximum relief of 4 m per 100 m). Where the principal slip zone of a fault ruptures to the surface, scarp morphologies are characterized by steep gradients (ca. 10 m per 100 m). Discrete faulting is imaged in GPR as structural lineaments, abrupt changes in the thickness of reflector packages with variations of amplitude, and/or hyperbolic diffraction packages indicative of the disturbance of reflector packages. Geophysical imaging of subtle changes in the shallow geological structure during growth of fault-propagation folds can be conducted using GPR informing the identification of locations for invasive investigations (e.g., trenching).

The modern drainage systems of the fold and thrust belt of the external Hellenide orogen of NW Greece are principally orogen-parallel. Late Quaternary changes in river courses have resulted from neotectonic deformation associated with the Katouna–Stamna fault and with footwall uplift in developing transverse grabens. This study assesses the impact of neotectonic deformation on river patterns and basin deposition. River sands show differences in modal abundance and varietal geochemistry of heavy minerals and fine sand lithic clasts, determined by scanning electron microscope, that allow identification of past river supply to raised fluvial terrace and beach deposits. In the past 200 ka, footwall uplift south of developing grabens at Lake Trichonis and the Amvrakikos Gulf promoted orogen-transverse flow, diverting the Arachthos-Louros rivers to the west, causing reversal of drainage to the north in the lower reach of the Acheloos River. A raised terrace gravel south of Preveza records the southwestward flow of a large paleo-Arachthos river, confirmed by sand petrology in beaches farther south on the Echinadon Sea coast. The use of varietal heavy minerals and lithic clasts is a rapid and powerful tool for tracking tectonically-induced changes in river patterns.

Seismicity in the intraplate southwest of Western Australia is poorly understood, despite evidence for potentially damaging earthquakes of magnitude > M6. Identifying stress-focusing geological structures near significant earthquake sequences assists in understanding why these earthquakes occur in seemingly random locations across a region of more than 250 000 km2. On 16 September 2018, an ML5.7 earthquake occurred near Lake Muir in the southwest of Western Australia and was followed by an ML5.4 aftershock. The main earthquake formed a mainly north-trending fault scarp ∼5 km in length and with a maximum vertical displacement of ∼40 cm. The main event was followed by a series of aftershocks, one of which had a magnitude of ML5.4. Using high-resolution aeromagnetic data, we analyse bedrock geology in a wide area surrounding the new scarp and map a series of major ∼ east–west-trending faults segmenting eight distinct geological domains, as well as a network of less prominent northwest-trending faults, one of which aligns with the southern segment of the scarp. Surface faulting, surface deformation and earthquake focal mechanism studies suggest movements on north- and northeast-trending structures. The main shock, the aftershocks, surface faulting and changes in InSAR-derived surface elevation all occur in a region bounded to the south by a prominent northwest-trending fault and to the north by a west-northwest-trending domain-bounding structure. Thus, we interpret the north-trending thrust fault associated with the main Lake Muir event as due to local stress concentration of the regional east–west stress field at the intersection of these structures. Further, we propose that a particularly large west-northwest-trending structure may be broadly focusing stress in the Lake Muir area. These findings encourage similar studies to be undertaken in other areas of Australia's southwest to further the current understanding of seismic release in the region. A large ML5.7 earthquake occurred in southwest Western Australia in September 2018, damaging infrastructure and forming a 40 cm-high thrust fault scarp. An aeromagnetic interpretation of the Lake Muir region revealed that the new scarp aligned with pre-existing faults that were reactivated. Local and regional structures likely acted as regional stress focusers in the Lake Muir area. Identifying regional stress-focusing structures is important for the purpose of understanding seismic risk in intraplate areas such as Western Australia. [ABSTRACT FROM AUTHOR]

Fractal investigation isa valuable technique to model and quantify the composite patterns of natural similar objects. This study investigates Neotectonics using ASTER-GDEM. Fractal technique for extraction of topographic fractal dimension (Dtopo) and vertical dissection (Rtopo-surf) were used to assess the Neotectonics deformation. Geomorphological regions can be demarcated by using above mentioned procedures as they reveal the topographic evolutionary stages as an evaluation of topographic textures. The idea is to recognize the zones that are strongly influenced by Neotectonics. Astore-Deosai-Skardu (ADS) region in Gilgit-Baltistan was selected for this purpose as it lies between MKT and MMT which is experiencing surface topographic deformation (STD) caused by anti-clock-wise progression and subduction of Indian plate beneath Eurasia. The results obtained illustrates that Dtopo and Rtopo-surf show anomalies in the ADS region that clearly represent a robust control of nearby MMT, MKT and KkF and highlights their significance to describe regions vulnerable to Neotectonics and related deadly events threatening precious human lives and infrastructure damages.

As a result of melting of the last ice sheet in the southeastern edge of the Fennoscandian shield, ridge structures called eskers were formed. One of these eskers is the subject of our study. We have identified both typical non-deformed sedimentary layers and specific intrusive mixture of sand and silt in the esker. The sand and silt were deformed with formation of recumbent and overturned folds, which indicate that they have experienced displacement in a ductile (wet) state. The formation of similar dislocations (diapir folds or glacial intrusion structures) can occur as a result of either dead ice melting or liquefaction during earthquakes.

Abstract The Southeastern Brazilian Margin presents a NE-SW-striking structural framework, which is characteristic of the Neoproterozoic Ribeira Belt. Other important structural trends along the area are associated with E-W and NW-SE-striking structures, being most related to the Mesozoic-Cenozoic tectonic evolution. A succession of Cenozoic tectonic events has been described by many authors in the Southeastern Brazilian. Among those Cenozoic tectonic events, a Neogene to Quaternary E-W dextral strike-slip regime (EW-DT) shows a wide distribution, presenting some variations in the stress field orientation. This research investigates the influence of the preexisting structural framework on the variation of the paleostress field orientation associated with the EW-DT tectonic event in a selected area in the onshore continental margin of the Southeastern Brazil. The study was carried out in three main stages: lineament analysis, paleostress field analysis, and numerical mechanical modeling. The paleostress field related to the EW-DT tectonic event in the studied area presents: NNW-SSE-striking maximum horizontal stress, and counterclockwise rotation influenced by the structural framework. Regarding this, the regional variation of the paleostress field is influenced by a preferential reactivation of NE-SW-striking structures while sets of approximately E-W-striking structures are the main local control of counterclockwise rotation of the stress field.

Khadg Singh Valdiya, a stalwart amongst Indian geoscientists is widely recognised and highly respected for his pioneering works on Himalayan geology and environment. Besides being a recipient of the highest Civilian Awards: Padma Shri and Padma Bhushan, he was the awardee of numerous prizes, awards, honours and fellowships [1]. His significant contributions to the stratigraphic, structural and tectonic evolution of the Himalaya laid the foundation for several ongoing studies in the Himalaya. Valdiya also made noteworthy contributions to the tectonic rejuvenation of the central Sahyadri mountains, and the origin and disappearance of the prehistoric Saraswati river in northwest India. Valdiya wielded enormous influence on the Indian geoscience academic community through the many books that were authored by him on Indian stratigraphy, Himalayan geology, the Saraswati river, neotectonics of the Indian sub-continent, and environmental geology. [ABSTRACT FROM AUTHOR]

We present the effect of neotectonics in intracratonic settings as revealed by the surface, brittle deformation associated to a regionally-sized shear corridor, which affects Southeastern Brazil. The deformation zone is characterized by the presence of nearly orthogonal fracture sets, interpreted as systematic and non-systematic joints often cutting Quaternary deposits. An original methodology of fault and joint inversion by the Monte Carlo converging approach is used to infer multiple paleostress fields. The method provides the best orientation of the principal paleo-stresses responsible for the observed fracturing. At each step of the inversion process, structures are uniquely associated to the stress tensor that provides the lowest error. The results showed the poly-phased tectonic history of the shear corridor studied and paleostresses compatible with a regional strike-slip motion. Specifically, an E-W, left-lateral shear was followed by an E-W, right-lateral kinematics related to the post-Paleogene drifting of South American Plate and its clockwise rotation. The latter tectonic event is presently responsible for brittle deformation observed in Quaternary deposits. The proposed deformation corridor may represent the Cenozoic reactivation of an ancient weakness zone. We speculate that the described intraplate strike-slip deformation belt represents the continental prosecution of the Rio de Janeiro fracture zone.

Northern Apennines is tectonically an active fold and thrust belt. Digital Elevation Model (DEM) based drainage network was extracted to analyze river profiles to document the influence of neotectonics on landscape evolution in Rossenna river basin, northern Apennines Italy. This approach decodes the neotectonic signals by computing channel steepness, Hack stream-length gradient (HSLG) and knickpoints analyses. The main objective was to examine how spatially variable rock uplift relate to changes in river morphology. The results obtained are consistent with the recent tectonic uplift of the region. The presence of knickpoint anomalies and higher values of steepness and HSLG index in south west region and the lower segments of Rossenna River indicate high relative uplift in these areas, which is related to the presence of strikeslip and thrust faulting. It is concluded that these results are useful to constrain the active tectonics in a simpler and faster way using river profile analysis.

The basement of southeast Brazil is traditionally interpreted as the result of Neoproterozoic and early Paleozoic orogenic cycles. Wide regions of the Atlantic Plateau (southeast Brazil) are characterized by rocks and tectonic structures of Precambrian age. According to the classical literature, these regions have not been affected by tectonics since the Miocene, despite the fact that they rest close to Cenozoic basins, which have suffered recent tectonic deformation. The objective of this research is to evaluate the role of neotectonics in the Atlantic Plateau. This task is accomplished through a multiscalar approach which includes lineament domain analysis from regionally sized digital elevation models and structural geology field surveys. Lineaments are automatically detected and statistically analyzed. Azimuthal analyses of data on faults and fractures by a polynomial Gaussian fit enables the identification of the main structural trends. Fault-slip direct inversion by means of the original Monte Carlo approach allows one to compute the multiple paleostresses that produced the measured fault population. The results show the presence of a principal ENE–WSW lineament domain, related to an old shear zone possibly reactivated since the Miocene. One of the paleostresses computed from fault-slip inversion is in agreement with the neotectonic stress-field proposed by other authors.

Abstract Over the last decade, studies of natural hazards in Sumatra have focused primarily on great earthquakes and associated tsunamis produced by rupture of the Sunda megathrust. However, the Sumatran Fault and the active volcanic arc present proximal hazards to populations on mainland Sumatra. At present, there is little reliable information on the maximum magnitudes and recurrence intervals of Sumatran Fault earthquakes, or the frequency of paroxysmal caldera-forming (VEI 7–8) eruptions. Here, we present new radiocarbon dates of paleosols buried under the voluminous Ranau Tuff that constrain the large caldera-forming eruption to around 33,830–33,450 calender year BP (95% probability). We use the lateral displacement of river channels incised into the Ranau Tuff to constrain the long-term slip rate of two segments of the Sumatran Fault. South of Ranau Lake, the Kumering segment preserves isochronous right-lateral channel offsets of approximately 350 ± 50 m, yielding a minimum slip rate of 10.4 ± 1.5 mm/year for the primary active fault trace. South of Suoh pull-apart depression, the West Semangko segment offsets the Semangko River by 230 ± 60 m, yielding an inferred slip rate of 6.8 ± 1.8 mm/year. Compared with previous studies, these results indicate more recent high-volume volcanism in South Sumatra and increased seismic potency of the southernmost segments of the Sumatran Fault Zone.

The activity of normal faults in the Central-Western Pyrenees is mainly detected by the disruption of paleic landforms surviving to Plio-Quaternary incision: the remnants of a Low-Relief Topography (LRT) that probably originated asynchronically during the Oligocene and Miocene. We propose a new method for mapping the LRT remnants that combines automatic analysis of digital topography and cross-checking with regional databases of Quaternary landforms. We focus on an area where the location of the main-drainage divide seems to be influenced by the activity of the Bedous-Pic de Midi du Bigorre set of faults and by the North Maladeta Fault. Neotectonic markers defined by the remnants of LRT envelops are tectonically displaced up to ~700m by the previously identified faults, but also along new faults observed in between them. A western prolongation of the North Maladeta Fault has been identified for the first time, implying a 75km total trace length, almost twice the previously published value. A restoration of the fault block motion was performed assuming a regional uplift across the range, enhanced in the northern part of the Axial Zone. This uplift leads to an outer arch extension along the Maladeta-Bedous Fault System. The resulting paleo-topography shows a broad southern paleo-flank (up to ~120km long) with a gentle regional gradient (~1º) and a much shorter and steeper northern paleo-flank (~4º gradient, up to 30km-long). This configuration suggests that the LRT remnants now located North of the main divide were connected to the Ebro Basin. The results are supported by previous studies on age and source provenance of major alluvial systems mantling the northern and southern flanks of the chain.

The Roer is a small river which drains the Rhenish shield and confluences with the Meuse River. Up to now the geological, climatological, biostratigraphical, and pedological setting of the Roer Valley were not sufficiently integrated to disentangle the effects of external forcing factors on the Roer River. In this study we perform a detailed and integrated reconstruction of the fluvial morphology and palaeogeography of the Roer River in order to determine responses to combined climatic, tectonic and anthropogenic forcing factors. The Roer River has formed five terrace levels since the Weichselian Late Pleniglacial. Fluvial planform of the Roer River was predominantly climate-controlled during the Lateglacial and Early Holocene. Reach-to-reach variations in river terrace formation and fluvial planform change occur due to variations in tectonic setting, subsurface geology, base-level fluctuations and the confluence with tributary systems. Differential subsidence by active faulting in the Roer Valley Graben during the early Lateglacial caused a preferential usage of the down-tilt channels of the, up to then, double channel belt systems in the Roer Valley. This preferred channel avulsion towards a fault zone, leaving an underfit system on the up-tilted side, and the clustering of Holocene Roer channels along that fault zone, meet the criteria for a lateral response of the Roer River to a tectonic forcing. Anthropogenic influences in the form of deforestation and land-use changes during the Late Holocene are responsible for the formation of a final terrace level and overbank sediments. Unlabelled Image • River terraces of the Roer River were formed by combined external forcing factors. • The avulsion of the Roer River during the early Lateglacial was tectonically forced. • Reach-specific terrace formation and preservation is present in the Roer Valley. • Late Holocene terrace formation in the Roer Valley was anthropogenically forced. [ABSTRACT FROM AUTHOR]

Numerical models were developed in order to provide a suitable computational framework for exploring research questions related to long-term landscape evolution. We used the Channel-Hillslope Integrated Landscape Development (CHILD) model to prove three hypotheses concerning the processes contributing to the neotectonic landscape evolution of the Tribeč Mts. and the Pohronský Inovec Mts. (Western Carpathians): (1) simultaneous planation and uplift; (2) temporally and spatially varying uplift; (3) exhumation of a part of the area from below Neogene sediments. Given the size of the area, its lithological variability and the insufficient knowledge of the palaeogeographical settings, using a detachment-limited model to express river incision into bedrock as well as water (rill) erosion on hillslopes proved the best solution. Results of the simulations were compared with real topography through hypsographic curves and the distribution of remnants of planation surfaces. The real surface corresponds best to a combination of the hypotheses (2) and (3), with more intensive Quaternary tectonic uplift of the Pohronský Inovec Mts. and the adjacent Rázdiel part of the Tribeč Mts., and exhumation of a mature palaeosurface from below Miocene sediments in the east of the Tribeč Mts.

For the first time, Quaternary thrusts are documented within the Central Oman Mountains to the northwest of the Jabal Akhdar Dome. Thrusts with a throw of up to 1.1 m displace Quaternary alluvial fan conglomerates. These conglomerates have an Optical Stimulate Luminescence (OSL) age of 159 ± 7.9 ka BP and were deposited during MIS 6 (Marine Isotope Stage). The thrusts occur in two sets. Sets 1 and 2 formed during NE/SW and NW/SE shortening, respectively. Set-1-thusts correlate with the present-day stress field of NE/SW shortening which is related to subduction in the Makran Subduction Zone, and they strike parallel to the main continuous fold axis of the Jabal Akhdar and Hawasina windows. Set-2-thrusts correspond to NW/SE shortening and Plio-Pleistocene contractional structures in the southwestern Jabal Akhdar Dome. Set-2-thrusts are probably related to local variations of the present-day stress field originating from the Musandam area which is a part of the Zagros Collision Zone. Both thrust sets mimic the main thrust directions (NW/SE and NE/SW) within the Permo-Mesozoic allochthonous units (Semail Ophiolite, Hawasina napps) of the larger study area. The investigated thrusts imply some reactivation of the Hawasina and Semail thrusts due to far-field stress either from the Makran Subduction Zone and/or the Zagros Collision Zone. The ongoing tectonic activity of this part of the Oman Mountains, which has been considered of moderate activity, is for first time identified by structural data as contractional.

The Vigan-Aggao Fault is a 140-km-long complex active fault system consisting of multiple traces in the westernmost part of the Philippine Fault Zone (PFZ) in northern Luzon, the Philippines. In this paper, its traces, segmentation, and oblique left-lateral strike-slip motion are determined from horizontal and vertical displacements measured from over a thousand piercing points pricked from displaced spurs and streams observed from Google Earth Pro satellite images. This work marks the first instance of the extensive use of Google Earth as a tool in mapping and determining the kinematics of active faults. Complete 3D image coverage of a major thoroughgoing active fault system is freely and easily accessible on the Google Earth Pro platform. It provides a great advantage to researchers collecting morphotectonic displacement data, especially where access to aerial photos covering the entire fault system is next to impossible. This tool has not been applied in the past due to apprehensions on the positional measurement accuracy (mainly of the vertical component). The new method outlined in this paper demonstrates the applicability of this tool in the detailed mapping of active fault traces through a neotectonic analysis of fault-zone features. From the sense of motion of the active faults in northern Luzon and of the major bounding faults in central Luzon, the nature of deformation in these regions can be inferred. An understanding of the kinematics is critical in appreciating the distribution and the preferred mode of accommodation of deformation by faulting in central and northern Luzon resulting from oblique convergence of the Sunda Plate and the Philippine Sea Plate. The location, extent, segmentation patterns, and sense of motion of active faults are critical in coming up with reasonable estimates of the hazards involved and identifying areas prone to these hazards. The magnitude of earthquakes is also partly dependent on the type and nature of fault movement. With a proper evaluation of these parameters, earthquake hazards and their effects in different tectonic settings worldwide can be estimated more accurately.

Tectonically deformed cave passages in the Tatra Mts (Central Western Carpathians) indicate some fault activity during the Quaternary. Displacements occur in the youngest passages of the caves indicating (based on previous U-series dating of speleothems) an Eemian or younger age for those faults, and so one tectonic stage. On the basis of stress analysis and geomorphological observations, two different mechanisms are proposed as responsible for the development of these displacements. The first mechanism concerns faults that are located above the valley bottom and at a short distance from the surface, with fault planes oriented sub-parallel to the slopes. The radial, horizontal extension and vertical σ1 which is identical with gravity, indicate that these faults are the result of gravity sliding probably caused by relaxation after incision of valleys, and not directly from tectonic activity. The second mechanism is tilting of the Tatra Mts. The faults operated under WNW-ESE oriented extension with σ1 plunging steeply toward the west. Such a stress field led to normal dip-slip or oblique-slip displacements. The faults are located under the valley bottom and/or opposite or oblique to the slopes. The process involved the pre-existing weakest planes in the rock complex: (i) in massive limestone mostly faults and fractures, (ii) in thin-bedded limestone mostly inter-bedding planes. Thin-bedded limestones dipping steeply to the south are of particular interest. Tilting toward the N caused the hanging walls to move under the massif and not toward the valley, proving that the cause of these movements was tectonic activity and not gravity.

The Kangra Reentrant is a convex-to-the-northeast U-shaped structure in the NW Himalaya, where the Sub-Himalayan fold-and-thrust belt is ∼90 km wide. This region has not been struck by large earthquakes since the 1905 Mw 7.8 Kangra Earthquake. Out-of-sequence deformation has been reported at the millennial timescale along intracrustal thrusts within this reentrant, such as the Jawalamukhi Thrust. Up to now, the occurrence of out-of-sequence deformation along inner thrusts within the Kangra Reentrant, during the Late Quaternary, has not yet been addressed. In this study, the results of a neotectonic survey undertaken in this reentrant are presented; the studied zone is located between the Beas and the Neogad rivers, and encompasses from the Jawalamukhi Thrust to the Main Boundary Thrust. Two terraces that are deformed by branches of the Medlicott-Wadia Thrust, locally named the Palampur Thrust, are identified; this is evidenced in the field by metric-scale fault scarps. By using 10 Be dating, the ages of these terraces were constrained to ca. 7.5 and ca. 6.2 ka. This is clear evidence of the Late Quaternary out-of-sequence deformation in the innermost part of this reentrant, implying that strain is distributed along all the arc-orthogonal extent of the local fold and thrust belt over this timespan. A cumulative slip rate of ca. 1 mm/yr along the studied thrusts, which represents 10% of the bulk-strain accommodated by the whole reentrant for this timespan, is calculated. In spite of the marginal appearance of this figure, this deformation rate is attributed to 7  < Mw < 8 earthquakes triggered along the brittle/ductile zone of Main Himalayan Thrust and emerging at the surface along crustal ramps, such as those represented by the Palampur Thrust in the study area. Earthquakes of this magnitude may severely impact the Kangra District, which currently hosts 1.5 million people. [ABSTRACT FROM AUTHOR]