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We compile detrital 10Be concentrations of Alpine rivers, representing the denudation rates pattern for 375 catchments across the entire European Alps. Using a homogeneized framework, we employ state-of-the-art techniques for inverting in-situ 10Be concentrations into denudation rates. From our compilation, we find that (i) while lithologic properties and precipitation/runoff do influence erosion mechanisms and rates at the scale of individual catchments and in some specific Alpine regions, such controls do not directly stand for the entire Alps, (ii) as also previously suggested, catchment-wide denudation rates across the entire European Alps closely follow first-order Alpine topographic metrics at the scale of individual catchments or selected Alpine sub-regions. However, in addition to previous local-scale studies conducted in the European Alps, our large-scale compilation highlights a functional relationship between catchment-wide denudation and mean catchment slope angle. Catchment-wide denudation positively correlates with mean catchment slope up to a threshold angle (25–30°). Above this threshold, any correlation between catchment-wide denudation and slope as well as other catchment metrics breaks apart. We can reconcile these systematic patterns by proposing a regional erosion model based on diffusive-transport laws for catchments located below the slope threshold angle. In oversteepened catchments situated above-threshold slopes, erosion is stochastic in nature, as glacial carving likely caused a partial decoupling between hillslope and fluvial domains with complex topographic relationships and sediment connectivity patterns. Finally, we identify a first-order positive relationship between modern geodetic rock uplift and catchment-wide denudation for the European Alps. The observed spatial pattern is highly variable and possibly reflects the surface response to deep geodynamic mechanisms prevailing in the different Alpine regions. We conclude that today's topography and geomorphic features of the entire Alps are the result of a millenial-scale geomorphic response to past glacial processes and active rock uplift, highlighting a link between external and internal drivers for mountain erosion. ISSN:0012-8252 ISSN:1872-6828

International audience; Despite a wealth of recent studies dealing with the evolution of the drainage network in the uplifted Ardennes massif (E. Belgium), especially from the Middle Pleistocene onwards, the Ardennian landscape evolution and long-term incision rates in the Meuse catchment remain poorly documented over the whole Plio-Quaternary. Alluvium-filled multilevel cave systems represent a relevant setting to unravel the Late Cenozoic history of regional river incision. We present here a dataset of 26 Al/ 10 Be concentration data obtained from fifteen pebble samples washed into the Chawresse system, one of the largest multi-level cave systems of Belgium, which developed in Devonian limestones of the lower Ourthe Valley, the main Ardennian tributary of the Meuse. The sample collection spans an elevation difference higher than 120 m and their depleted 26Al/10Be ratios yield burial ages ranging from ~0.25 to 3.28 Ma. After critical assessment of our dataset for intra-karstic reworking issues, the most striking outcome of the obtained burial ages is the acceleration by a factor five of the incision rates (from ~30to ~150 m/Ma) during the first half of the Middle Pleistocene. Integrating this incision peak and our pre-burial denudation rates, we then revisit the existing framework of Plio-Quaternary denudation and river incision in the Ardennian Meuse catchment. Whilst our 26Al/10Be concentration data shed new light on the temporal andspatial variability of the local river and hillslope system response to coupled tectonic and climatic forcings, it simultaneously highlights sampling issues and the need for further chronological data.

Fluctuations in suspended sediment concentration (SSC) has been investigated in the Warta River (western Poland), based on data obtained for the period 1961–1980 from three gauge stations located in upstream, middle-stream and downstream areas. Over the two decades, the SSC values demonstrated wide fluctuations and an overall increase at each gauge station. No significant correlation was generally observed between SSC and discharge but high SSC was found to follow low discharge and increasing temperature during the summer seasons in some years. Measurements of SSC and discharge were used to estimate total annual suspended sediment load (SSL). SSL values were found to increase downstream along with an increase in discharge. SSC decreases along the river course. However, when it comes to changes over time, SSL variability was mainly determined by SSC changes. The maximum SSC values were primarily caused by anthropogenic factors: the disposal of mine wastewater upstream, river training works, increased urbanisation and the intensification of sewage disposal. Where the river catchment has been greatly affected by anthropogenic factors, a denudation index calculated solely based on SSC and discharge does not appear to reflect the actual denudation rate, and must be treated with caution.

International audience; The East Carpathian volcanic range experienced an along-arc, Late Miocene to Quaternary migration of eruptive activity during its ~11 Ma-long activity. Here, a novel and complex methodology is presented that yields new geochronological and geomorphological constraints on the evolution of the 20 volcanic edifices. New unspiked K-Ar ages either constrain their lifespan (6.79 ± 0.10–6.47 ± 0.09 Ma for Seaca-Tătarca; 5.47 ± 0.08–4.61 ± 0.07 Ma for Vârghiş) or date the youngest volcanic activity (central Călimani). In parallel, numerical reconstructions of volcanic paleo-topographies were performed to quantify their shape at the end of their construction stage. The inferred initial volcano size shows a wide range (3 to 592 km3), making up the four main successive volcanic segments (910, 880, 279 and 165 km3 for Călimani, Gurghiu, North Harghita and South Harghita segment, respectively) totalizing 2200 km3 and an average growth rate of 200 km3/Ma at range-scale. At the volcano-scale, with only consideration to their respective time spans (i.e. avoiding repose periods), growth rate is characterized by two major trends: a moderate growth rate (137 km3/Ma) for the older volcanoes (11–3.6 Ma) followed by a lower growth rate (28 km3/Ma) obtained for the Plio-Quaternary volcanoes. Comparing reconstructed and current topographies yielded a total eroded volume of 524 ± 125 km3, defining averaged denudation of 22% and a 20 m/Ma erosion rate. Erosion rates for major climatic periods were computed, which highlight the contrasting climatic contexts since 11 Ma. The highest erosion rate (38 m/Ma) occurred during transitional moderate subtropical-continental climate period (9.5–8.2 Ma). An intermediate erosion rate (14 m/Ma) characterized a moderate continental climate period (8.2–6.8 Ma) when conditions became less humid. The lowest erosion rate (7 m/Ma) reflects the prevailing continental but occasionally semi-arid climate (6.8–5.8 Ma). The highest erosion rate (28 m/Ma) was obtained for Plio-Quaternary times during the interglacial/glacial cycles. Such a quantitative morphometric and geochronological approach demonstrates its efficiency to study volcanic dynamism, including both constructional and erosional processes, through time.

Dividing carbonate sequence with natural gamma data is the popular method, while it is not suitable for shallow platform because high gamma of mud flat represent shallow-water environment. Taking Majiagou Formation of Ordovician in Bozhong 21–22 structure of Bohai Sea as an example, a new sequence division method for shallow platform was presented based on natural gamma spectrum data, and the relationship between the sequences and reservoirs was discussed as well in this paper. The high natural gammas in Majiagou Formation of the study area are response for the weathering, uranium element enrichment in reservoirs and argillaceous sediment. The comparison result between well logging parameters and geological data shows that the ratio of Th/K is an effective parameter for sequence division, which can distinguish the origin of different high gammas effectively, even the mudstone from oxidized environment and reductive environment. Based on the ratio of Th/K, five third-order sequences were divided in Majiagou Formation of the study area; among them, all the sequences are developed in well BZ21-B-1, while SQ5 is missing in well BZ22-A-2 for denudation. The corresponding relationship between sequences and reservoirs indicates that the reservoirs of SQ4–SQ5 are dominated by structural fractures, which are mainly controlled by tectonic movement and weathering; while those of SQ1–SQ3 are dominated by dissolved pores, which may be related to the internal dissolution.

In the mountainous landscapes of mainland Norway, fluvial processes and contemporary fluvial denudation occur in both non-glacierized and glacierized (glacier-connected) drainage basin systems. Fluvial processes in non-glacierized cold climate drainage basins are driven by snowmelt or rainfall, or by combinations of snowmelt and rainfall, whereas fluvial processes in glacier-connected drainage basin systems are generated by snowmelt, glacier melt or rainfall, or by combinations of snowmelt/glacier melt and rainfall. Contemporary chemical and mechanical fluvial denudation rates in drainage basins of the partly glacierized and very steep mountain landscape of the inner Nordfjord in western Norway and of the non-glacierized and less steep mountain landscape located south of the Trondheim fjord in central Norway are found to be rather low, with mechanical fluvial denudation being significantly higher in the steeper and partly glacierized mountain landscape of the inner Nordfjord as compared to the studied mountain landscape in central Norway. In the partly glacierized mountain landscape of the inner Nordfjord mechanical fluvial denudation clearly dominates over chemical denudation, whereas the non-glacierized mountain landscape in central Norway is characterized by a clear dominance of chemical denudation over mechanical fluvial denudation. In the inner Nordfjord pluvially triggered denudational process events and pluvially activated sediment sources in ice-free surface areas as well as pluvially induced fluvial suspended sediment transport are, with respect to their overall contribution to drainage basin-wide annual suspended sediment yields, more important than the mostly thermally induced suspended sediment transport during the summer (glacier ablation) or in spring (snowmelt). However, the highest quantitative share of fluvial bedload transport occurs here during thermally generated snowmelt peak runoff in spring which is due to a significantly higher availability of bedload material within the mainstream channels as compared to time periods later in the hydrological year. Compared to that, in the studied non-glacierized mountain landscape in central Norway, the highest quantitative share of the total fluvial transport occurs during thermally induced snowmelt peak runoff in spring. With respect to the total annual sediment mobilization and total annual fluvial sediment transport, the sum of snowmelt-generated peak runoff events occurring over the hydrological year is here altogether more important than the annual sum of purely rainfall-generated peak runoff events. While the larger topographic relief and the partly glacial coverage in the mountain landscape of the inner Nordfjord are important factors for the higher mechanical fluvial denudation rates, the clearly higher importance of extreme pluvial events with respect to mobilization and transport of sediments within the drainage basins of this mountain landscape as compared to drainage basins in the non-glacierized mountain landscape south of the Trondheim fjord in central Norway must be highlighted. Fluvial transport in the studied fluvial systems in western and central Norway is clearly supply limited. It is expected that postulated changes of the current wind, air temperature and precipitation regimes will lead to increased chemical and mechanical fluvial denudation rates in both partly glacierized drainage basin systems in western Norway and non-glacierized drainage basin systems in central Norway.

The present study deals with the morphometric quantification of erosion and illustrates the uplift component triggered by denudation (isostasy) in the growth and evolution of a rising orogeny by the application of Airy isostasy concepts. The Gibraltar Arc, located in the Western&ndash, Central sector of the Betic Cordillera, developed an exceptional geological scenario during the Messinian Salinity Crisis since the thin emerged fringe of the uprising Cordillera disconnected the Atlantic and Mediterranean basins, generating a relevant misbalance and asymmetry in the fluvial erosion between the two slopes of the emergent orogeny. Our analysis was applied to 50 individual drainage basins (spatial isostatic units) in the Western&ndash, Central Betic Cordillera, allowing us to obtain individual and bulk estimates for these isostatic parameters. GIS-based numerical estimations were obtained using LiDAR Digital Elevation Models (DEMs) provided by the Spanish Geographical Institute and reconstructed pre-incision surface models obtained from proxy paleo-elevation data, estimated from stratigraphic and geomorphological littoral to shallow marine markers. The obtained values for geophysical relief, denudation plates, erosion/uplift rates and computed accumulated uplift (245&ndash, 407 &plusmn, 20 m) are higher for the ancient Mediterranean slope of the orogen. On the contrary, the Atlantic slope presents an accumulated uplift of only 138&ndash, 236 &plusmn, 20 m, indicating the strong control of the ancient Messinian Atlantic&ndash, Mediterranean water divide. The temporal study of erosion indicates that most of the difference in uplift in the Mediterranean slope was achieved during or soon after the Messinian Salinity Crisis, resulting in mean uplift rates of 0.21 mm/y, but practically null (0.01 mm/y) for the Atlantic slope. The comparison of the geophysical relief models with proxy paleo-elevation data allowed us to assess the current state of the denudation process in the range. The results indicate that, towards the west of the range denudation compensated elevation, and is actively back-feeding isostatic rebound. Therefore, the contribution of external processes to mountain range elevation through isostasy is quantitatively estimated using elevation data. In this case, a relevant part of the surface uplift (50-55%) is undertaken by the orogen. Ultimately, the Messinian Salinity Crisis-related isostatic response to differential denudation may be behind the quaternary westward tilting of Iberia, causing more than 70% of the Peninsula to drain towards the Atlantic.

Sediment Routing Systems (SRS) and Sediment Generation (SG) are two branches of sedimentary geology which are complementary, although their full integration remains incomplete. SRS connect all the steps of the journey of sediments from their formation to final deposition in relation to the denudation of sediment sources, the transfer of erosional products and their final deposition. SG is a branch of provenance analysis focussing on the quantification of the processes governing the production (Qs) and dispersal of sediments from known parent rocks, and the prediction of the amount and compositional-textural properties of sediments produced under given tectonic and climatic settings. The integration of the two disciplines is fundamental to tackle some of the open problems in sedimentary geology, including (i) the dynamics regulating the generation and release of sediments from upstream catchments to the floodplains, (ii) particle trajectories, (iii) residence time and mineralogical modifications in temporary storage environments (iv) sediment selective extraction and (v) the shredding of environmental signal propagation in both (vi) actualistic and deep-time SRS. I introduce all the elements which are necessary to both disciplines, with particular emphasis on quantitative provenance analysis (QPA). The SG approach is required to quantify lithological controls on Qs, and include it into the stream power law. QPA and the ‘Provenance Toolbox’ provide the compositional framework which is necessary for the characterisation of the erosional products. Both the advantages and limitations of each analytical tool are explored, and best practices for successful analytical workflows are discussed in light of a full integration into SRS research.

Denudacija je proces snižavanja površine Zemlje, a koji uključuje procese trošenja i erozije. Glavni čimbenici koji utječu na intenzitet denudacije su klima i litologija. Na području Dinarida, prvenstveno izgrađenih od karbonatnih stijena, denudacija ne samo da mijenja debljinu karbonatnih stijena, već se mijenjaju hidraulika i kemijski uvjeti koji utječu na trošenje stijena i oblikovanje reljefa. Postoji nekoliko grupa metoda mjerenja denudacije površine, no na području Dinarida uglavnom se koriste metode mjerenja gubitka mase vapnenačkih pločica izloženih otapanju u različitim okolišima, te direktna mjerenja na izloženim površinama s mikro-erozijskim metrom. Cilj ovog rada bio je proučiti objavljena znanstvena istraživanja vezana za denudaciju Dinarskog krša, te dati pregled najvažnijih metoda i njihovih rezultata. Na intenzitet denudacije utječe više različitih čimbenika. Klima utječe na intenzitet denudacije tako što u humidnoj suptropskoj i gorskoj umjerenoj klimi dolazi do najvećeg trošenja, dok se u aridnoj i semiaridnoj klimi na površini pločice talože karbonatne soli i time se masa pločica povećava. Intenzitet korozije u različitim vrstama tla ovisi o različitom sastavu, strukturi, vlažnošću tla i količini CO2. Rezultati mjerenja su međusobno različiti zbog specifičnosti svakog mjesta. Denudation is a process of Earth's surface lowering, which includes the processes of weathering and erosion. The main factors influencing the intensity of denudation are climate and lithology. In the area of the Dinarides, primarily built of carbonate rocks, denudation not only changes the thickness of carbonate rocks, but also changes the hydraulics and chemical conditions that affect rock weathering and relief formation. There are several groups of methods used for measuring of surface denudation, but in research on Dinaric area measuring the loss of mass of limestone tablets exposed to weathering in different environments, and direct measurements on exposed surfaces with a micro-erosion meter are mainly used. The aim of this thesis was to review published scientific papers related to the denudation of the Dinaric karst, and to provide an overview of the most important methods and their results. The intensity of denudation is affected by several different factors. Climate affects the intensity of denudation so that in humid subtropical and mountain temperate climates the greatest wear occurs, while in arid and semiarid climates carbonate salts are deposited on the surface of the tablet and thus the mass of the tablets increases. The intensity of corrosion in different soil types depends on different composition, structure, soil moisture and amount of CO2. The measurement results are different due to the specifics of each place.

Facets are major topographic features built over several 100 k.y. above active normal faults. Their development integrates cumulative displacements over a longer time frame than many other geomorphological markers, and they are widespread in diverse extensional settings. We have determined the 36Cl cosmogenic nuclide concentration on limestone faceted spurs at four sites in the Central Apennines (Italy), representing variable facet height (100–400 m). The 36Cl concentration profiles show nearly constant values over the height of the facet, suggesting the facet slope has reached a steady-state equilibrium for 36Cl production. We model the 36Cl buildup on a facet based on a gradual exposure of the sample resulting from fault slip and denudation. Data inversion with this forward model yields accurate constraints on fault slip rates over the past 20–200 k.y., which are in agreement with the long-term rate independently determined on some of those faults over the past 1 m.y. 36Cl measurements on faceted spurs can therefore constrain fault slip rate over time spans as long as 200 k.y., a time period presently undersampled in most morphotectonic studies.

Fission-track analysis in zircon and apatite detrital grains from Mesoproterozoic sedimentary sequences show evidence of cooling episodes in central Brazil from Neoproterozoic to Cenozoic. Apatite fission-track ages reveal a main cooling episode during the Late Cretaceous-Early Paleogene, providing important clues on cooling by uplift and denudation during drifting of South America and Africa. Zircon data also suggest 3 distinct cooling events: (i) a Neoproterozoic-Cambrian event, probably related to orogenic exhumation of the Brasilia Belt and the thermal decay of West Gondwana assembly, (ii) a Devonian-Carboniferous event, probably related to the Late Famatinian orogeny and early stages of the Gondwanide orogeny, and (iii) an Early Permian to Triassic event, linked to the Late Gondwanide orogeny. These results indicate that the processes of assembly and breakup of supercontinents might significantly affect the plate interior, especially along with ancient orogenic belts. Zircon data has shown evidence of thermal decay during and after the West Gondwana assembly. Apatite data, on the other hand, has shown evidence of thermal decay during and after the breakup of Pangaea. The processes of assembly as well as the breakup of supercontinents can be tracked in the intracratonic setting, especially along with ancient orogenic belts. These assumptions take us back to the old concept of “mobile belts” as old orogenic regions that represent weak portions of the continental crust, assumed to have a greater tendency for mobility when solicited. In this case, the Brasilia Belt has shown to present great vertical mobility, accommodating tectonic far-field forces by uplift and as a result, feeding the Phanerozoic basins around it.

The relationship between the spatial variability of soil elements, weathering and erosion rates can be very complex. Topography, abruptly-changing elevation gradients and slopes of varying geological composition exert an important influence on weathering trajectories and erosion. This complex interconnectivity is only rarely addressed in weathering studies. The main objectives of this investigation are, therefore, to relate weathering and erosion to various and geomorphic units in a dry-alpine and threshold landscape having steep slopes (Kan catchment, Tehran Province, Iran). A number of common weathering indices were tested using a genetic algorithm. The best indices are the (K + Na)/Ti ratio, the WIP (weathering index according to Parker), and the PI (product index according to Ruxton). However, the recently suggested 4Si-M+-R2 and M-F-Wmin systems discriminate weathering trends more accurately. Our results show that these soils have a low to moderate weathering stage. Weathering trajectories point to the active formation of kaolinite and oxyhydroxides. River sediments are slightly more weathered and contain the most-weathered topsoils and suggest erosion in the catchment is predominantly due to topsoil removal. Chemical weathering is influenced by the dominant geomorphic units (unconsolidated deposits of the Quaternary and solid bedrock) and landform features (combination of altitude and slope). Aspect does not appear to have a significant impact on weathering. Denudation (~erosion) rates were determined using meteoric 10Be since the fluvial sediments did not contain enough quartz for in situ 10Be analyses. This procedure has higher uncertainties due to difficulties in estimating the depositional flux of meteoric 10Be. Due to tectonic uplift, the erosion rates are very high. To maintain a soil layer, soil production rates must be also high. Although annual precipitation is relatively low, slope and soil dynamics seem particularly high, which leads to a fast turnover of the soil material and maintains the weathering intensity at a rather low to intermediate level.

East Antarctica remains one of the few continental regions on Earth where an understanding of the origin and causal processes responsible for topographic relief is largely missing. Low‐temperature thermochronology studies of exposed Precambrian basement revealed discrete episodes of cooling and denudation during the Paleozoic-Mesozoic; however, the significance of these thermal events and their relationship to topography across the continental interior remains unclear. Here we use zircon and apatite (U‐Th)/He thermochronology to resolve the low‐temperature thermal evolution of a poorly exposed section of East Antarctic basement in the Bunger Hills region and gain insights into the chronology and style of landscape evolution across East Antarctica. Thermal history modeling results indicate that Precambrian basement in the Bunger Hills region experienced a distinct cooling episode during the Late Paleozoic-Triassic, which we relate to ~2-4 km of regional exhumation associated with intracontinental rifting, followed by a second episode of localized cooling and ≤1 km exhumation during the Late Jurassic-Cretaceous separation of India from East Gondwana. These findings, combined with existing thermochronological and tectonic evidence, support a continent‐scale denudation event associated with uplift and exhumation of large sections of Precambrian basement during Late Paleozoic-Triassic Pangea‐wide intracontinental extension. By contrast, continental extension associated with the Jurassic-Cretaceous breakup of East Gondwana resulted in significant denudation only locally in regions west of the Bunger Hills. We propose that the combined effects of these Paleozoic-Mesozoic tectonic events had a profound impact on the topography across the East Antarctic interior and influenced the long‐term landscape evolution of East Antarctica.

The Copper Basin (CB) of southeastern Tennessee, known as the Ducktown Mining District, is a classic example of forest and soil destruction due to extensive mining and smelting operations from the mid-1800s until 1987. The smelting operation released a sulfur dioxide by-product that formed sulfuric acid precipitation which, in combination with heavy logging, led to the complete denudation of all vegetation covering 130 km2 in CB. The area has since been successfully revegetated. This study used remote sensing technology to map the different episodes of this vegetation recovery process. A time series of Landsat imagery acquired from 1977 through 2017 at 10-year intervals was used to map and analyze the changes in vegetation cover in CB. These maps were used to generate a single thematic map indicating in which 10-year period each parcel of land was revegetated. Analysis shows that the extent of non-vegetated areas continuously decreased from about 38.5 to 2.5 km2 between 1977 and 2017. The greatest increase in vegetation regrowth occurred between 1987 and 1997, which was the period when all mining and smelting activities ceased. This research could be very useful to better understand the recovery process of areas affected by mining and smelting processes.

Meteoric 10Be (10Bemet) concentrations in soil profiles great potential as a geochronometer and a tracer of Earth surface processes, particularly in fine-grained soils lacking quartz that would preclude the use of in situ-produced 10Be (10Bein situ). One prerequisite for using this technique for accurately calculating rates and dates is constraining the delivery, or flux, of 10Bemet to a site. However, few studies to date have quantified long-term (i.e. millennial) delivery rates. In this study, we compared existing concentrations of 10Bein situ with new measurements of 10Bemet in soils sampled from the same depth profiles to calibrate a long-term 10Bemet delivery rate. We did so on the Pinedale and Bull Lake glacial moraines at Fremont Lake, Wyoming (USA) where age, grain sizes, weathering indices, and soil properties are known, as are erosion/denudation rates calculated from 10Bein situ. After ensuring sufficient beryllium retention in each profile, solving for the delivery rate of 10Bemet via Monte Carlo simulations, and normalizing to Holocene-average paleomagnetic intensity, we calculate best-fit fluxes of 0.92 (+/− 0.08) × 106 and 0.71 (+0.09/−0.08) × 106 atoms cm−2 y−1 to the Pinedale and Bull Lake moraines, respectively, and compare these values to two widely-used 10Bemet delivery rate estimation methods. Accurately estimating 10Bemet flux using these methods requires careful consideration of spatial scale as well as temporally varying parameters (e.g. paleomagnetic field intensity) to ensure the most realistic estimates of 10Bemet-derived erosion rates in future studies.

The Tor Exhumation Approach (TEA) traditionally uses large residual granitic landforms as indicators for surface lowering over time of their surrounding landscape. This study challenged the broad applicability of this approach by using large metamorphic residual landforms instead of the traditional plutonic rock formations. We applied in-situ cosmogenic nuclide techniques (10Be) along vertical landforms (schist-tors) on the Otago upland in southern New Zealand to investigate the capabilities of the TEA within another major rock type. The aim of the investigation was to decipher surface denudation models for the last ~100 ka. The experiment was coupled with fallout radionuclides (239+240Pu) in nearby soils to compare the Pleistocene / Holocene surface denudation rates with the Anthropocene (last ~60 years).The surface ages of the eight investigated schist-tors was between ~20 ka and ~300 ka. This allowed the numerical modeling of continuous surface denudation rates with highest values near 0.16-0.20 [mm year-1] (about 140–180 [t km-2year-1]), and over a period that has not yet been achieved. The fallout radionuclide study resulted in two different mass redistribution rates. Average soil erosion along a ridge was ~400 to ~850 [t km-2year-1], whereas in an adjacent valley soil deposition rates reached ~130 to ~1,500 [t km-2year-1]. In conclusion, this study provides a new basis on how schist-tors emerge at two different landscape positions (ridges and valleys). In addition, differences between past surface denudation rates and modern ones could be revealed.

Thermal denudation is a combination of the processes responsible for the formation of retrogressive thaw slumps (cryogenic earth flows) and thermocirques. Thermocirques are the depressions with a semi-circle shape resulting from tabular ground ice thaw. Environments characteristic of Сentral parts of Yamal and Gydan peninsulas forming the so called Kara sub-latitudinal transect, are favorable to activation of thermal denudation. The key factors are continuous permafrost distribution and shallow occurrence of tabular ground ice.An increase in ground temperature and active layer thickness in 2012-2013 cause the intensification of thermal denudation along Kara sub-latitudinal transect. Field studies in the area of “Vaskiny Dachi” research station as well as remote sensing of 2018 data demonstrates the presence of both active and stabilized thermocirques during.This research presents preliminary results of collecting and analyzing the distribution of more than 400 landforms caused by thermal denudation identified in central Yamal and central Gydan peninsulas. Coastal thermodenudation landforms were not taken into account to exclude the influence of wave erosion in this study. Such work became possible due to free of charge satellite images with a very high spatial resolution available at the service Yandex.Maps (https://yandex.ru/maps/).In Yamal peninsula, we identified 63 active and 53 stabilized thermodenudation landforms, in Gydan peninsula, 169 active and 166 stabilized, respectively. Active thermodenudation features concentrate in the western and southern parts of central Yamal, while stabilized dominate in western and central parts. In central Gydan both active and stabilized features of thermal denudation are located at northwestern part and are distributed more evenly compared to Yamal. Northern border of all identified thermodenudation features for both Yamal and Gydan peninsulas is located at 71 degrees North, and the southern border at 69 degrees North. Despite the difficulties of visual interpretation of thermal denudation features, we defined the majority of them as thermocirques, most of which are located along lake coastlines. Such indication was also confirmed by in-situ data collected during multiyear field campaigns in the study area. These results reveal a prevalence of thermal denudation features in the study area and the collected data gives us an opportunity for spatial analysis of their distribution.The reported study was partially funded by RFBR according to the research project #18-05-60222

Measurements of chemical and physical rates of landscape change in the tropics are rare. To address this data gap, a joint US/Cuban science team has worked together for two years sampling across the island of Cuba. Here, we report long-term cosmogenic erosion rates inferred from river sand paired with rates of chemical denudation estimated from river water solute loads. Together, these data define source-to-sink mass transport in 45 drainage basins in western and central Cuba and allow us to speculate on the role of agriculture on nutrient and sediment fluxes.Rates of erosion determined from in situ 10Be concentrations range from 2 yr) in central Cuba and from 11 to 125 tons/(km2 yr) in western Cuba. Chemical denudation rates and total dissolved solids are several times higher in central Cuba than western Cuba. River water is dominated by Mg, Ca, Na, K, and Si in both areas.Although cosmogenic erosion rates are often interpreted as total landscape denudation, we find in some Cuban drainage basins that 10Be-based erosion rates underestimate total landscape denudation. Considerable discordance (12-60X) between erosion rates and chemical denudation rates in five central Cuban basins suggests that significant mass loss by solution is not reflected by cosmogenic-based erosion rates. In 2 of these basins, erosion rates calculated from duplicate measurements of 10Be (1.4 & 2.5 m/My) and 26Al (1.7 & 2.9 m/My) were ~50X lower than chemical denudation rates (89 & 108 m/My). Both 26Al and 10Be concentrations indicate long term, near-surface (>>100 ky) quartz residence; stream water geochemical data are consistent with the presence of evaporite deposits. We suspect that rapid chemical denudation enriches basin sediment in quartz, which lingers at or near the surface in these low slope (0.5°) basins.Despite centuries of agriculture, the impact on Cuban river biogeochemistry is limited. Although river water in many central Cuban rivers has high levels of E. coli bacteria, likely sourced from livestock, concentrations of nitrate are far lower than other areas where intensive agriculture is practiced, such as the Mississippi River Basin. This suggests the benefits of Cuba’s shift to conservation agriculture after 1990 and provides a model for more sustainable agriculture worldwide.

The denudation of soil or soft rock surfaces by non-concentrated flow is mostly estimated by relating the sediment discharge observed at the outlet of a plot or natural micro-catchment to their respective surface areas. This approach generates an average denudation rate, but ignores spatial patterns of erosion and deposition. A well established approach to capture such spatial differences are pins, which deliver a highly precise point measurement of surface elevation change. Advances in the development of Unmanned Aerial Vehicles (UAVs) and imagine processing in the past decades offer an additional tool for mapping erosion and deposition at millimetre scale for continuous surfaces. In this study, pin and UAV-derived erosion data for a badland area in the Karoo rangelands, South Africa, are compared. The results show that typical annual erosion rates in the study area are lower than the differences between two DEMs generated a year apart. This illustrates that in situations where erosion rates are low, pins still offer the faster and more reliable results. For their extrapolation, on the other hand, UAV-derived DEMs provide suitable topographic data.

Cirque erosion contributes significantly to mountain denudation and is a key element of glaciated mountain topography. Despite long-standing efforts, rates of rockwall retreat and the proportional contributions of low-, mid- and high magnitude rockfalls have remained poorly constrained. Here, a unique, terrestrial LiDAR-derived rockfall inventory (2011–2017) of two glaciated cirques in the Hohe Tauern Range, Central European Alps, Austria is analysed. The mean cirque wall retreat rate of 1.9 mm a−1 ranks in the top range of reported values and is mainly driven by enhanced rockfall from the lowermost, freshly deglaciated rockwall sections. Retreat rates are significantly elevated over decades subsequent to glacier downwasting. Elongated cirque morphology and recorded cirque wall retreat rates indicate headward erosion is clearly outpacing lateral erosion, most likely due to the cataclinal backwalls, which are prone to large dip-slope failures. The rockfall magnitude-frequency distribution – the first such distribution derived for deglaciating cirques – follows a distinct negative power law over four orders of magnitude. Magnitude-frequency distributions in glacier-proximal and glacier-distal rockwall sections differ significantly due to an increased occurrence of large rockfalls in recently deglaciated areas. In this paper we show how recent climate warming shapes glacial landforms, controls spatiotemporal rockfall variation in glacial environments and indicates a transient signal with decadal scale exhaustion of rockfall activity immediately following deglaciation crucial for future hazard assessments.

In this study, we present analysis of stream flow near the snout of Chaturangi glacier during the ablation season (June to September (JJAS)) in the year 2015 with an aim to estimate the sediment and water input into the Bhagirathi River from the glacier. In order to assess the variation in meltwater discharge from Chaturangi glacier and to determine its relationship with suspended sediment concentration (SSC), the meltwater and discharge data were analyzed from near the snout to avoid mixing of water and sediment from other glacier tributaries. The meltwater discharge was measured by area velocity method, and the SSC was calculated by vacuum filtration technique. During the entire ablation season (JJAS), marked seasonal variations were observed in the SSC and meltwater discharge. The higher variation is observed in suspended sediment load (SSL) (Cv = 1.17) than SSC (Cv = 0.54) because computation of SSL includes both discharge (Cv = 0.76) and SSC. The average monthly SSC for JJAS was found to be 0.99, 2.29, 4.20, and 1.84 g l−1, respectively, and average monthly meltwater discharge for same period was observed as 5.83, 14.48, 39.81, and 12.69 m3 s−1, respectively. It suggested that throughout the ablation season, the cumulative percentage delivery of SSC follows meltwater discharge. The average suspended sediment yield (SSY) for the entire ablation season was estimated to be 2264.03 ton/km2, and consequent catchment denudation rate was measured as 0.85 mm. A strong positive correlation (r2 = 0.88), found between the discharge and SSC, revealed that both the parameters are dependent on each other. Our results also suggest that the Chaturangi glacier is a major contributor for transportation of sediment into the Bhagirathi River, compared with other tributaries of the Gangotri glacier system.

Topographic relief in arc-trench systems is thought to be formed by plate subduction; however, few quantitative investigations have so far been reported, with respect to the related mountain building process. This study applies apatite and zircon (U–Th)/He thermochronometry (AHe, ZHe, respectively) to Cretaceous granite rocks in the north part of the northeast (NE) Japan Arc to reveal its cooling/denudation history. Weighted mean AHe ages ranging from 88.6 to 0.9 Ma and ZHe ages from 83.9 to 7.4 Ma were determined for 10 rock samples. Using the AHe data, denudation rates were obtained for each sample. On the fore-arc side, denudation rates of 0.1–1.0 mm/year were computed, probably reflecting a recent uplift event since ~ 3–2 Ma. These data indicate a clear contrast in thermal and denudation histories between the tectonic units in this study area, similar to that previously reported from the southern part of NE Japan Arc. A comparison of the thermal/denudation histories between the N- and S- traverses, revealed the arc-parallel trend, the uplift model of the volcanic arc, and some minor variations of thermal/denudation histories in each tectonic unit. This study offers some further insights into the understanding of tectonic processes in an island-arc setting.

Made available in DSpace on 2020-12-12T01:00:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-02-15 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Chemical weathering and soil erosion in large or small watersheds are used to understand the effect of evolution processes on the Earth's surface and climate. Currently, human-driven land use changes have substantial effects on landscape changes over a range of temporal and spatial scales. In this context, the Sorocaba River basin, São Paulo State, Brazil, is an ideal study area to assess human influence on the present denudation rates of the Paulista Peripheral Depression (PPD). Twelve fluvial water sample collections were carried out at the Sorocaba River mouth, covering one complete hydrological cycle (Jun/2009 to Jun/2010). In the same period, 46 rainfall events were sampled. All samples were analyzed for dissolved cations, anions and silica, and total dissolved solids (TDS). Total suspended solids (TSS) were measured only in fluvial samples. The export of TDS and TSS occurs mostly during the wet season, accounting for ca. 60% and 87% of the total dissolved solids and total suspended sediment transported in the hydrological cycle studied (2009/2010), respectively. The total annual specific flux of TSS was 74.27 t/km2/year (including soil erosion by agricultural activities), with a small portion being derived from the anthropogenic contributions (ca. 2%). The total annual specific flux of TDS (74.43 t/km2/year) was similar to the TSS, but after the correction of the atmospheric inputs and anthropogenic contributions (ca. 18 and 29%, respectively), this value decreased to 39.35 t/km2/year. The chemical weathering rate was 7.1 m/Myear and this process tended towards monosialitization (RE = 2.6), with an atmospheric/soil CO2 consumption rate of 3.3 × 105 mol/km2/year. The difference between the chemical weathering and soil removal rates (7.1 and 49.6 m/Myear, respectively) indicated that the soil thickness reduction occured in the Sorocaba River basin. The climatic control on chemical weathering and soil removal rates was clearly evidenced, with the highest values of denudation occurring in the wet and hot climatic conditions. However, the chemical weathering processes (RE index) was not sensitive to climatic controls. In order to assess human influence on chemical weathering and soil removal rates in the PPD, the results were compared with other works undertaken in this vast geomorphological province. Even considering the uncertainties associated with a number of data points, the chemical weathering and soil removal rates in the PPD observed in this study were approximately 4 and 7.5-fold higher than these natural denudation rates, respectively, evidencing the effect of recent land use changes on the present denudation rates in the PPD. Thus, this study reinforces the complexity of the human-landscape systems in São Paulo State and increases the values of long-term landscape evolution rates. UNESP – Universidade Estadual Paulista - Instituto de Geociências e Ciências Exatas. Rio Claro Catchment and Eco-hydrology group – Luxembourg Institute of Science and Technology Centro de Energia Nuclear na Agricultura - Universidade de São Paulo. Piracicaba UNESP – Universidade Estadual Paulista - Instituto de Geociências e Ciências Exatas. Rio Claro FAPESP: 08/09369-9 FAPESP: 08/57104-4 CNPq: 134169/2009-3

As reverse weathering has been shown to impact long‐term changes in atmospheric CO2 levels, it is crucial to develop quantitative tools to reconstruct marine authigenic clay formation. We explored the potential of the beryllium (Be) isotope ratio (10Be/9Be) recorded in marine clay‐sized sediment to track neoformation of authigenic clays. The power of such proxy relies on the orders‐of‐magnitude difference in 10Be/9Be ratios between continental Be and Be dissolved in seawater. On marine sediments collected along a Chilean margin transect we chemically extracted reactive phases and separated the clay‐sized fraction to compare the riverine and marine 10Be/9Be ratio of this fraction. 10Be/9Be ratios increase fourfold from riverine to marine sediment. We attribute this increase to the incorporation of Be high in 10Be/9Be from dissolved biogenic opal, which also serves as a Si‐source for the precipitation of marine authigenic clays. 10Be/9Be ratios thus sensitively track reverse‐weathering reactions forming marine authigenic clays., Plain Language Summary: Clay minerals can form on land by the chemical breakdown of rock‐forming minerals, but clays can also form in the ocean. When clay formation takes place in the ocean, CO2 is released. To date, there is no method that can easily measure the amount of clay minerals formed in the ocean. We used two isotopes of the same element, beryllium (Be), with the atomic mass of 9 and 10 to test whether this isotope system can be used to measure marine clay formation. The abundance of these isotopes differs majorly on land and in the ocean. We measured beryllium isotopes in river sediment and ocean‐bottom sediment offshore the Chile coast and compared the ratios of the isotopes (10Be/9Be). The ratio is four times higher in ocean sediment, when compared to river sediment. We interpret this increase to be due to the formation of clay minerals in the ocean, which include the high 10Be/9Be ratio during their formation. We conclude that the beryllium‐isotope system can be used to measure the formation of even very small amounts (less than 2%) of marine clay minerals. This is important, as the clay‐forming chemical reactions release CO2 which has a long‐term effect on global climate., Key Points: We explored the potential of the beryllium isotope ratio to track neoformation of marine authigenic clays. Beryllium isotope ratios increase fourfold from riverine to marine sediment due to the presence of marine Be incorporated in authigenic clay. Beryllium isotope ratios sensitively track reverse‐weathering reactions forming marine authigenic clays., Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659, IPGP multidisciplinary program PARI and by Paris‐IdF region SESAME Grant 12015903

Denudation is a key parameter controlling the formation and evolution of landforms across the Earth's surface. The interaction between surface processes (namely denudation) and climatic variations at the geological time scale is a highly debated issue, due to the lack of continuous sedimentary records unaffected by tectonic forcing. In order to constrain this interaction, this thesis focuses on the Var watershed (French Maritime Alps) and on its sedimentary archive which allow to track the variations of denudation rates from the present until 75 000 years ago. This period covers the end of the last glacial cycle (the Würm) as well as the transition to the current climatic period (the Holocene). The measurement of 10Be (cosmogenic isotope) in sediments allows the quantification of denudation rates integrated over the entire watershed. This method, applied to present-day sediments of the Var, constrained the current denudation rate of the Var catchment at 0.24 ± 0.04 mm yr-1. The same method was then applied to samples from two sedimentary cores constituting a continuous and high-resolution sedimentary archive of past Var sediments. The results show that the Last Glacial Maximum glaciers' advance (between 19 000 and 26 500 years) induced a significant increase on denudation (~ × 2), whereas during the previous glacial stages (between 26 500 and 75 000 years), the denudation was steady and similar to present-day value. This nonlinear response of denudation to climate change suggests the existence of a threshold controlled by the erosive dynamics of glaciers, which was close to ~ 2 mm yr-1 during the Last Glacial Maximum and ~ × 4 lower between 75 000 and 26 500 years.; Le processus de dénudation est un paramètre clé contrôlant la formation et l'évolution des reliefs terrestres. L'interaction entre les processus de surface (notamment la dénudation) et les variations climatiques à l'échelle des temps géologiques est une question fortement débattue, et ce à cause du manque d'enregistrements continus non affectés par la dynamique tectonique. Afin de contraindre cette interaction, cette thèse se focalise sur le bassin versant du Var (Alpes Maritimes Françaises) et sur ses enregistrements sédimentaires qui permettent un suivi des variations des taux de dénudation depuis le présent jusqu'à il y a 75 000 ans. Cette période couvre la fin du dernier cycle glaciaire (le Würm) ainsi que la transition vers la période climatique actuelle (l'Holocène). La mesure du 10Be (isotope cosmogénique) dans les sédiments permet la quantification des taux de dénudation moyennés sur l'ensemble d'un bassin versant. Cette méthode, appliquée aux sédiments actuels du Var, a permis de calculer un taux de dénudation actuel s'élevant à 0.24 ± 0.04 mm yr–1. La même méthode a ensuite été appliquée sur des échantillons provenant de deux carottes sédimentaires constituant un enregistrement continu et haute résolution des sédiments du Var. Les résultats montrent que l'avancée des glaciers pendant le Dernier Maximum Glaciaire (entre 19 000 et 26 500 ans) a entrainé une augmentation significative (~ × 2) des taux de dénudation, tandis que lors des précédentes phases glaciaires (entre 26 500 et 75 000 ans) la dénudation était constante et similaire à la valeur actuelle. Cette réponse non-linéaire de la dénudation aux changements climatiques suggère l'existence d'un seuil contrôlé par la dynamique érosive des glaciers, qui était proche de ~ 2 mm yr–1 pendant le Dernier Maximum Glaciaire et ~ × 4 plus faible entre 26 500 et 75 000 ans.

This paper presents a detailed provenance analysis of the 6.5-km thick Oligocene–Pliocene foreland succession in the north Dezful embayment in Zagros, Iran. Using petrography, geochemistry, and paleoflow analysis, we determined three provenance shifts during the exhumation of Zagros orogen. Above the Ahwaz sandstones, sourced from the Arabian craton, a sharp decrease in SiO2/Al2O3, Zr/Sc, Th/Sc, Th/Co and Th/Cr within the Gachsaran Fm., and the appearance of first-cycle sands derived from metamorphic and volcanic rocks at the base of Aghajari Fm., characterize the onset of exhumation, rising topography and denudation of the Zagros orogenic system during latest Oligocene and constitute the first shift. The second shift, in middle Aghajari Fm., is marked by a distinct increase in radiolarian cherts and compatible/incompatible elements, indicating the exhumation of Neo-Tethyan radiolarite-ophiolite allochthonous slices in the High Zagros Zone during Tortonian (∼9 Ma). A vast number of carbonates derived from nearby growing Izeh Zone anticlines characterize the Messinian (∼7 Ma) Bakhtyari conglomerates marking the third shift. In conclusion, a detailed hands-on provenance analysis of the clastic sedimentary sequences in the north Dezful embayment enabled us to determine catchment areas and shifts hitherto unstudied thus contributing to the exhumation history of the Central Zagros orogenic system., This study was financially supported by the Institute for Advanced Studies in Basic Sciences (grant numbers G2017IASBS52752 and G2017IASBS12670) and by projects ALPIMED (PIE-CSIC-201530E082) and SUBTETIS (PIE-CSIC- 201830E039).

Denudation is a key parameter controlling the formation and evolution of landforms across the Earth's surface. The interaction between surface processes (namely denudation) and climatic variations at the geological time scale is a highly debated issue, due to the lack of continuous sedimentary records unaffected by tectonic forcing. In order to constrain this interaction, this thesis focuses on the Var watershed (French Maritime Alps) and on its sedimentary archive which allow to track the variations of denudation rates from the present until 75 000 years ago. This period covers the end of the last glacial cycle (the Würm) as well as the transition to the current climatic period (the Holocene). The measurement of 10Be (cosmogenic isotope) in sediments allows the quantification of denudation rates integrated over the entire watershed. This method, applied to present-day sediments of the Var, constrained the current denudation rate of the Var catchment at 0.24 ± 0.04 mm yr-1. The same method was then applied to samples from two sedimentary cores constituting a continuous and high-resolution sedimentary archive of past Var sediments. The results show that the Last Glacial Maximum glaciers' advance (between 19 000 and 26 500 years) induced a significant increase on denudation (~ × 2), whereas during the previous glacial stages (between 26 500 and 75 000 years), the denudation was steady and similar to present-day value. This nonlinear response of denudation to climate change suggests the existence of a threshold controlled by the erosive dynamics of glaciers, which was close to ~ 2 mm yr-1 during the Last Glacial Maximum and ~ × 4 lower between 75 000 and 26 500 years., Le processus de dénudation est un paramètre clé contrôlant la formation et l'évolution des reliefs terrestres. L'interaction entre les processus de surface (notamment la dénudation) et les variations climatiques à l'échelle des temps géologiques est une question fortement débattue, et ce à cause du manque d'enregistrements continus non affectés par la dynamique tectonique. Afin de contraindre cette interaction, cette thèse se focalise sur le bassin versant du Var (Alpes Maritimes Françaises) et sur ses enregistrements sédimentaires qui permettent un suivi des variations des taux de dénudation depuis le présent jusqu'à il y a 75 000 ans. Cette période couvre la fin du dernier cycle glaciaire (le Würm) ainsi que la transition vers la période climatique actuelle (l'Holocène). La mesure du 10Be (isotope cosmogénique) dans les sédiments permet la quantification des taux de dénudation moyennés sur l'ensemble d'un bassin versant. Cette méthode, appliquée aux sédiments actuels du Var, a permis de calculer un taux de dénudation actuel s'élevant à 0.24 ± 0.04 mm yr–1. La même méthode a ensuite été appliquée sur des échantillons provenant de deux carottes sédimentaires constituant un enregistrement continu et haute résolution des sédiments du Var. Les résultats montrent que l'avancée des glaciers pendant le Dernier Maximum Glaciaire (entre 19 000 et 26 500 ans) a entrainé une augmentation significative (~ × 2) des taux de dénudation, tandis que lors des précédentes phases glaciaires (entre 26 500 et 75 000 ans) la dénudation était constante et similaire à la valeur actuelle. Cette réponse non-linéaire de la dénudation aux changements climatiques suggère l'existence d'un seuil contrôlé par la dynamique érosive des glaciers, qui était proche de ~ 2 mm yr–1 pendant le Dernier Maximum Glaciaire et ~ × 4 plus faible entre 26 500 et 75 000 ans.

The Cenozoic landscape of northern South America evolved under the influence of different geodynamic processes, culminating in the formation of the largest drainage basin on Earth, the Amazon drainage system. The orogeny of the Andean cordillera and the increase in surface denudation induced an asymmetric influx of sediments in Amazonia, which caused an eastward propagation of the Andean sedimentary wedge, reversing the topographic gradient and driving the drainage flow towards the Atlantic Equatorial margin. The low-relief topography of lowlands in Amazonia is also a factor that propitiates this reversal. Concomitantly, variations in the subduction angle of the Nazca plate under the continental lithosphere during the Miocene also contributed to create dynamic topography that perturbed the surface and modified the drainage pattern through time. In the last decade, both surface processes during Andean orogeny and dynamic topography were invoked independently to explain the formation of the present Amazon drainage system connecting the Andes and the equatorial margin. However, hitherto these mechanisms were not considered in a single model, hampering the evaluation of the contribution of each factor on the evolution of the Amazon River. To quantify the combined effect of the different geodynamic processes, in the present work we used numerical models that integrate orogeny, surface processes, dynamic topography and flexural isostasy of the lithosphere. In our results, we present new numerical scenarios for the Cenozoic landscape evolution of Amazonia, showing that the dynamic topography may have affected the environmental evolution in western Amazonia, favoring the development of a megawetland in this region before the establishment of the Amazon River as a transcontinental river. We conclude that, although the formation of the Amazon drainage system can be explained without the influence of mantle convection, variations in dynamic topography may have anticipated the establishment of the transcontinental drainage system a few million years. Furthermore, the stratigraphic evolution and the total Cenozoic sedimentation preserved in the Solimoes Basin is a function of the temporal variations in the amplitude of dynamic topography in northern South America.

The tectonic activity and potential for linkage of adjacent active faults are crucial for seismic assessment. As the two largest faults that bound the Weihe Graben (central China), the Qinling Northern Piedmont Fault (QNF, ~200 km) and the Huashan Piedmont Fault (HPF, ~150 km) are mainly responsible for seismic risk in this densely-populated area, where the 1556 M 8.5 Huaxian earthquake occurred with 830,000 fatalities. However, their tectonic activity and the degree of interaction remain poorly constrained, hampering an adequate seismic risk assessment of the Weihe Graben. Here, we integrate 23 new 10Be-derived catchment-averaged denudation rates of ~0.06–0.32 mm/yr with topographic metrics to evaluate the seismic risk. The results demonstrate that the landscape of the Qinling and Huashan Mountains is in transient state in response to the tectonic perturbations of the QNF and the HPF, with tectonic knickpoints formed along main streams and tributaries, and widespread unstable drainage divides. These two faults have comparable tectonic activity, and are potentially capable of generating earthquakes with the maximum magnitude of Mw ~7.7–7.9. Moreover, they have likely started linking, posing a greater seismic risk than previously estimated.

The main production layers of Zhenyuan and Yanwu oilfields in the southwest of Ordos basin are Triassic Chang 3 reservoir. However, studies on the formation mechanism and distribution rules of high-quality reservoirs in this formation are not perfect at present, which limits the integration process of exploration and development to some extent. Based on the sedimentary characteristics, tectonic movement, reservoir characteristics, diagenesis and other basic geological research, through the analysis of feldspar detritus content, secondary solution pores, feldspar dissolved pore content, and face rate such characterization parameters of longitudinal change rule of the reservoir characteristics, exploring the Chang 3 reservoir mechanism and distribution of this area. It is believed that meteoric fresh water penetrates into Chang 3 formation along unconformity surface formed by weathering denudation and river corrosion, and dissolution can changes reservoir properties to form high quality reservoir. Therefore, the paleogeomorphologic units of the pre-jurassic residual interfluvial mound and the lateral slope zone of the valley are usually overlapped with the growth range of high-quality reservoir, which is a favorable target area for exploration and development. Through exploration and development practice, eight Chang 3 reservoirs were discovered and developed successively, realizing the rapid advancement of the integration of exploration and development and providing reference for the efficient exploration and development of the same type of reservoirs.

The Mendip Hills, located in southwestern England, is a geologically diverse area that admirably demonstrates the strong interplay between geology, denudation and geomorphology. A thick sequence of Upper Palaeozoic sandstones and limestones were folded and thrusted into a series of en-echelon periclines that were denuded during the Triassic. A long history of successive marine transgressions during the Mesozoic led to the planation and eventual burial of the Palaeozoic strata. More recent uplift and erosion during the Quaternary have partially stripped this younger cover to reveal elements of the old Triassic landscape. Karstification of the thick Lower Carboniferous limestones has created a spectacular karst landscape with rocky gorges, dry valleys, sinking streams and caves, including the major tourist attractions of Cheddar Gorge and Wookey Hole. The complex geological history has created a region with an exceptional range of geology and geomorphology within a comparatively small area. This geodiversity has attracted the attention of numerous geologists, geomorphologists and naturalists over the past few centuries, making the region a classic area for study. For this reason, the Mendips host many Sites of Special Scientific Interest (SSSIs) and has been designated an Area of Outstanding Natural Beauty.

Hillslopes represent areas of predominant denudation and constitute the transition and trajectory to floodplains; they play a crucial role in understanding the longterm landscape evolution of desert environments. However, although hillslope processes are known to be very slow or even stagnant in (hyper-) arid environments, process mechanisms under the virtual absence of water are poorly understood, and process rates are essentially unknown. Based on irrigation experiments, different monitoring techniques including drone-based high-resolution digital elevation models, geomorphological, stratigraphical, geochronological (OSL), sedimentological and geochemical investigations, as well as mu CT scans of sediment cores, this contribution presents detailed insights into the chronostratigraphy of tongue-shaped, 50 m-long and 30 m-wide fine sediment lobes located along a 10-30 degrees steep thrust-related slope east of the Salar Grande (Atacama, Chile). Irrigation experiments were performed to gain insights into precipitation thresholds for surface runoff and hillslope dynamics. Although artificial rainfall intensities were similar to 46 mm/h, infiltration was 100%, and the experiments did not initiate surface runoff or (detectable) slope material displacements. In addition, a distinct stratigraphic pattern with buried paleo-surfaces and paleo-biological surface crusts suggests increased hillslope activity during the late Pleistocene, potentially driven by changes of (fog-induced) humidity, salt-related shrink and swell processes, or paleo-seismic activity. While a variety of geo-bio-archives document periods of increased precipitation in the Andean parts of the Atacama Desert throughout the Quaternary, evidence for contemporaneous paleoclimatic changes from areas disconnected to Andean precipitation fluctuations (i.e., the Coastal Cordillera) is scarce. In this regard, the investigated landforms potentially represent one of only few sediment records recording paleoclimatic changes in the central desert, independent from Andean rainfall.