bluuebunny/crossref_metadata_2025 huggingface dataset:
Neotectonics, geochemical dispersion processes and mineral exploration: linking basement and surface in regions of cover
Authors: Gonzalez-Alvarez Ignacio , Krapf Carmen
Published: June 2022

Detection of mineral system footprints in regions under thick cover is challenging. The difficulties are enhanced in regions with low-relief landscapes that are deeply weathered. This is widely the case in Australia where >75% of the surface and subsurface is characterised by transported cover and/or deeply and intensely weathered profiles.

In a variety of geological-cover contexts, geochemical dispersion/concentration processes within cover units can be particularly efficient. These processes can produce near surface geochemical anomalies in the landscape, which may be expressions of mineral systems within basement units at depth’.

Basement structures in Earth’s crust are a well-recognised conduit for fluid flow, which can result in the formation of a large variety of mineral deposits (e.g., IOCG, hydrothermal Ni, SEDEX, etc). Therefore, identifying basement structures that may be associated with mineral deposit formation has become an important part of exploration protocols and prospectivity assessments.

The possible link between neotectonics and geochemical dispersion processes should be carefully considered when studying landscape geochemistry in areas with thick overburden.

Surface structures linked to principal basement structures which are intermittently reactivated may maintain a direct geochemical link between the basement and the surface. To efficiently resolve basement-derived geochemical signals, soil or surface landscape units should be selectively sampled in relation to these structures.

This study discusses how in areas of deep cover, neotectonic and/or reactivation surface landscape features have the highest probability to detect deep basement geochemical signatures at surface. This approach may have a critical impact in mineral exploration under cover in similar landscape contexts around the world, such as regions in Australia, West Africa, India, China and Brazil.
Evolution of pocket beaches on the island of Hvar during the last 200 years (Croatia, Eastern Adriatic Coast)
Authors: Mićunović Marin , Faivre Sanja
Published: June 2022

Beaches as dynamic coastal forms occur in different shapes, areas and lengths. They form at the interface between sea and land, where natural and socioeconomic processes interact. Their morphology changes on different temporal scales, from hours to centuries. In this work, the evolution of 25 beaches on the island of Hvar in Croatia was studied, covering the period from 1834 to 2021. The evolution of beaches was studied through three different periods. The oldest, starting from the year 1834, was analysed using the Franciscan cadastre (0.5 m error) mapped during the Austro-Hungarian Empire. Their surface areas were calculated using GIS software. Some of the beaches were already mapped as individual cadastral parcels. The obtained calculations significantly correlate with data from the Cadastral supplement (expressed in Klafter quadrimetre unit). The surface areas of beaches for the second period were estimated from archival orthophotos, provided by the State Geodetic Administration, using the method of repeat photography. The archival aerial photographs date from 1958 to 1968 and are in black and white colour with a relatively satisfactory resolution. The repeat photography method relies on more than 150 old photographs (1910-1980) that were used for benchmarking, beach boundary determination, and the reconstruction of mid-20th century situation. For the most recent period, which is the most accurate, we used UAV DJI Phantom 4 Pro in combination with a Trimble GNSS receiver. The fieldwork was conducted from November 2020 to March 2022. As a final product, very accurate orthophotos, DEM and DSM were produced by photogrammetric techniques in ESRI Drone2Map and Agisoft software. The analysis showed that beaches had the largest area during the cadastral survey, were slightly smaller in the mid-20th century and were the smallest in recent times. Consequently, beach erosion was found in all 25 sites surveyed. On average, the beaches have eroded by about 32% since the 19th century. Mina and Sveti Ante beaches were the most affected with more than 70%. Overall, the shoreline has moved inland of about 4.3 metres on average. It was found that cadastral data, archival maps, and old photographs proved to be useful and reliable data sources for analysing beach surface changes in the past.

This research was made with the support of the Croatian Science Foundation (HRZZ-IP -2019-04-9445).
Molards, a new geomorphological tool for the identification of permafrost degradation in periglacial terrains around the globe
Authors: Morino Costanza , Conway Susan , Deline Philip , Magnin Florence , Noblet Axel , Svennevig Kristian , Lucas Antoine , Strom Alexander , Dunning Stuart , Hermanns Reginald
Published: June 2022

Our study looks at how to use the landform called “molard” as a marker of permafrost degradation in arctic, sub-arctic and mountain environments. Molards in permafrost terrains are mound of loose debris that derive from the degradation of blocks of ice-rich sediments mobilised by a landslide. Such molards cannot form without ground ice, which cements the source material, allowing it to behave like solid during transport. Once the ground ice has thawed, its cementing action is lost, inducing collapse of the material into molards. We reconstruct the permafrost, geological, geographical settings of more than 50 landslides characterised by molards, compiling data available in the literature. We apply quantitative terrain analysis using high-resolution DEMs to describe, quantify and compare their topographic characteristics, morphometry, dynamics, and molards distribution and density. Our results show that landslides with molards can occur in terrains characterised by various permafrost distribution, from continuous to isolated. These landslides show a variety of morphological and morphometric characteristics, source materials often composed of loose debris or rheologically weak bedrock, and their molard distribution reflects the dynamics of the landslide. In this study, we show that molards are an indicator landform of permafrost degradation under different permafrost, geomorphological and geological conditions, and that they can be used to decipher landslide dynamics in cold environments.

Acknowledgements: This study is funded by the Agence Nationale de la Recherche in the framework of the project ANR-19-CE01-0010 PERMOLARDS
Ground surface temperature variation across scales on northeastern Qinghai-Tibet Plateau
Authors: Șerban Raul-David , Bertoldi Giacomo , Jin Huijun , Șerban Mihaela
Published: June 2022

Ground surface temperature (GST), measured at 5–10 cm into the ground, is essential for understanding the climate change impacts in the Earth Critical Zone, especially in cold regions. This work goal was to identify the GST variations from local to landscape scale on similar and different environmental conditions (e.g. elevation, landcover). The study area is located in the southern part of the Headwater Area of the Yellow River (HAYR), a representative area of alpine discontinuous permafrost on the Qinghai-Tibet Plateau. GST was recorded from 2019 to 2020 at 39 sites scattered on a local and landscape scale (2 and 50 km2), and on a transect along the highway with an elevational difference of 800 m. A statistically significant correlation was identified between mean annual GST (MAGST) with landcover (0.37, p <  0.05) and elevation (−0.76, p < 0.001). The analysis of variance (ANOVA) showed significant differences in MAGST between sites located in bare ground and vegetation but not between meadow and swamp meadow. At the local scale, the MAGST was higher in meadows (−0.3 to −0.6 °C) than in swamp meadows (−0.6 to −1.4 °C) and bare ground (−1.2 and −2 °C). The difference in MAGST between sites covered by vegetation and bare ground was 1.7 °C, and up to 1 °C between sites with the same landcover. The sites from the landscape scale revealed a similar pattern but with higher differences in MAGST, reaching 2.4 °C between vegetated and bare ground sites. The decrease of MAGST with elevation is most obvious for the sites located in bare ground (R2 = 0.83, p < 0.001) than in meadow (R2 = 0.64, p < 0.003) and swamp meadow (R2 = 0.49, p < 0.002). An elevational threshold was found at 4600–4700 m from where MAGST is becoming negative. The disturbance of the highway seems to influence the GST regime and subsequently the permafrost degradation. GST monitoring will help to identify the permafrost thaw patterns at a high spatial resolution, and to better understand the rapid shrinkage of thermokarst lakes in the HAYR.
Insights from a long-term monitoring system of a slow-moving landslide at Hofermühle, Lower Austria.
Authors: Marr Philipp , Stumvoll Margherita , Kanta Robert , Jimenez Donato Yenny Alejandra , Glade Thomas
Published: June 2022

The occurrence of landslides poses a significant threat to communities and infrastructure worldwide. Detailed knowledge of the triggering factors and process mechanisms of this geomorphic hazard still remains challenging. To reduce landslide risks, negative societal impacts and to deepen our understanding of the preparatory and triggering factors for landslide initiation, long-term monitoring approaches can be helpful. However, long-term monitoring projects required to study slow-moving landslides with varying periods of activity are rare due to financial and/or project time constraints. Here, we present the results of a long-term monitoring system, that includes a variety of methods to monitor the surface and subsurface of a slow-moving landslide, at the Hofermühle, in Lower Austria.

The region of Lower Austria is heavily affected by landslides. Therefore, the present research focuses on a small, retrogressive, slow-moving (cm-dm/a) earth slide-earth flow system of ~0.15 km2 at Konradsheim, Waidhofen/Ybbs in Lower Austria, which is representative of thousands of landslides in the region. It is located in a complex geological transition zone, of which the Flyschzone is known to be prone to shallow and deep landslides. It is characterized by high clay contents and the advanced weathering stage of the lithology. In addition, anthropogenic influences such as drainage mechanisms and land-use changes complicate the situation at the study site. Movements at the Hofermühle have been reported since the 1970s. In 2013, sliding processes increased in speed and magnitude, with heavy precipitation being the main trigger. As a result, monitoring systems were continuously established in 2014 and have been in operation since then. In this study, hydrometeorological data and remote sensing, such as UAV and TLS, combined with subsurface and geophysical data (e.g., inclinometers, TDR-probes, ERT) provide meaningful insights into the dynamics of slow-moving landslides.
Anthropogenic effect on the formation of Hiroshima Delta -Focusing on historical iron-sand mining in the upper reaches
Authors: Kubo Sumiko , Sadakata Noboru , Kumahara Yasuhiro , Iwasa Yoshiya , Matsumoto Akiko
Published: June 2022

The Hiroshima Delta is formed at the mouth of Ota River in western Japan. We conducted the grain analyses and radiocarbon dating of uppermost deposit of delta, along with detailed geomorphological mapping.  Grain analyses showed that particles in the uppermost part are of granitic origin, while lower part are of accretionary prism origin. Iron slag particles are confirmed in the uppermost part. Radiocarbon ages suggest they deposited after the 15th century. Geomorphological features of the lower Ota River plain show the development of sandy deposits. We concluded that the iron-sand mining and smelting in the upper reach caused rapid growth of the Hiroshima Delta.
Sedimentation from extreme summer 2021 flooding along the Maas River, Netherlands: The role of flood duration
Authors: Hudson Paul
Published: June 2022

Field data are reported for overbank sedimentation generated by the extreme flood event of summer 2021 along the Maas River, an intensively managed lowland river in the Netherlands. Flood duration was short (4 days) but flood magnitude was extreme, the highest stage and discharge recorded in more than 100 years (at Eijsden, NL).

Flood sediments were sampled at 108 sites from the NL-BE border to the delta (198-km distance) over a range of hydro-geomorphic environments. Flood deposits were sampled in August and September using conventional field sampling procedures, which included identifying recent sediment deposited atop buried soil and organic layers using field texture and density, and differences in soil color. Sedimentation thickness (mm) of each of the 108 reported values is an average of three individual thickness measurements obtained within a ~1 m radius at each field site. Minimum flood water height was measured by identifying silt and debris lines in vegetation and fencing at multiple locations. The particle size of 77 sediment samples was determined by standard hydrometer analysis and wet sieving to determine sediment indices (D10, D16, D50, D84, D90) to characterise particle size and sediment sorting.

Average flood deposit thickness was 19 mm, and varied from 0-mm to 295-mm across geomorphic settings: low floodplains, high floodplains, channel banks, and flood basins and did not exhibit downstream fining. Maximum sedimentation was associated with discreet sand sheets (295 mm). Floodplain stripping (erosion) at some low floodplain sites included reworking and deposition of large clasts (gravel, cobble). Pronounced lateral decreases in sedimentation thickness persists despite flood water height, and rapidly declines beyond about ~30 m from the channel bank. Lateral changes in particle size, however, are less abrupt, and along some reaches very fine sand was deposited to the distal margins of the floodplain. Some laterally distant sites > ~200 m from the channel bank underwent high amounts of sedimentation (38 mm, 25 mm, 43 mm) with pronounced vertical fining (very fine sand to silt) of flood deposits associated with slackwater sedimentation within basins engineered for the Room for the River flood management program. In contrast to many prior sedimentation studies a pattern of downstream fining does not exist, likely due to storage of silts in upstream reaches and downstream high stream power being able to rework of older channel bed deposits.

The thickness of the 2021 flood deposits are less than reported for large flood events in 1993 and 1995. This may be due to the shorter duration of the 2021 flood event, as well as the persistent decline in Maas River sediment loads since about the early 1950s, as well as differences in sampling strategy.
Geomorphological map of Greece
Authors: Karymbalis Efthimios , Tsanakas Konstantinos , Griva Diamantina , Batzakis Dimitrios-Vasileios , Valkanou Kanella
Published: June 2022

The present study is a geomorphological overview of Greece on a scale of 1:1,000,000. It is the first attempt of a cartographic synthesis that aims to bring together and interpret the geological and geomorphological factors that contributed to the landscape formation and evolution of Greece on a national scale. The production of the geomorphological map was based on a literature review of previous geomorphological studies of the greek terrestrial and coastal area at different scales as well as on the application of semi-automated, GIS techniques. High resolution topography obtained from the Hellenic Cadastre as well as the geological maps of Greece at a scale of 1:50,000 obtained from the Institute of Geology and Mineral Exploration of Greece were used as initial inputs in a spatial geodatabase for the production of a series of secondary layers. These layers, which included a hillshade map, a slope-aspect map, and a red relief image map, were combined with Google Earth Imagery to delineate small- and large scale landform across the Greek territory. The final map incorporates landforms of both endogenic and exogenic origin. It was organized genetically including structural landforms, landforms due to fluvial erosional and depositional processes, gravity induced landforms as well as coastal, karst, volcanic, glacial and periglacial landforms and anthropogenic facilities. A series of accompanying maps and tables were also produced, providing topographic parameters as well as information about the geotectonic setting and the climatic regime of Greece. The results show that the greek territory comprises a landscape with heterogeneous geomorphological environments, the formation and evolution of which, is the result of primarily active tectonics, and exogenic processes. The map reflects the extent of recent developments of geomorphology of Greece and can be used as a management tool for stakeholders, as well as a reference for further interdisciplinary research.
Knickpoint extraction for the evaluation of active tectonics: The case of Evia Ιsland, Greece
Authors: Valkanou Kanella , Karymbalis Efthimios , Vassilakis Emmanuel , Soldati Mauro , Papanastassiou Dimitris , Gaki-Papanastassiou Kalliopi
Published: June 2022

Τhis study aims to investigate to what extent the drainage systems of the northern part of Evia Island, in Central Greece, reflect the contemporary tectonic regime of the area. The effects of tectonic activity have been detected and described by performing a landscape morphological analysis of the drainage systems, followed by a field survey for validating the results. The Relative Declivity Extension (RDE) index, which is based on the Stream Length (SL) gradient index, was calculated along the channels of 189 drainage basins of the study area, using the Knickpoint Finder tool integrated into ArcGIS desktop. The Hack RDE index is defined by the ratio of the RDEs index (which refers to a stretch) and the RDEt index (which refers to the total length of a river) was applied, and its calculation identifies the knickpoints based on anomaly values detection along the longitudinal profiles of the rivers. Furthermore, knickpoint analysis was carried out along the channels of the drainage networks of the northern part of the Evia Island and the corresponding anomaly maps were designed. A total of 2,486 knickpoints were identified and the greatest anomalies (139 points), named first-order anomalies (RDE>10), seem to correspond to a recently shaped or rejuvenated landscape, indicative of intense neotectonic activity. In some cases, the spatial distribution of knickpoints delineates a NW-SE trending yielding the structural control of the study area. The comparison of the results with the lithological map of the area showed that about 30% of the knickpoints are lithologically controlled. The identification of zones of neotectonic activity and consequently the existence of active faults is highly correlated with the distribution of knickpoints and their core density, the drainage density, the drainage asymmetries, and other morphometric indices such as the hypsometric integral, along with the earthquake epicentres, and the morpho-lineament density. The overall analysis showed a positive correlation of the concentration of the derived knickpoints with both active structures and tectonic activity rates. The results were consistent with field observations, which were mainly focused on waterfall landforms. Our study proves that the landscape evolution of the northern part of the Evia Island is considerably affected by the recent activity of normal fault zones, whereas the drainage systems react to the changes of base-level providing insights on active tectonics.
Lessons from lidar: geomorphic mapping at the southern margin of the Cordilleran ice sheet
Authors: Haugerud Ralph
Published: June 2022

Geomorphic mapping from high-resolution (1-2 m XY, circa 5 cm Z) lidar topography of glacial and periglacial terrain at thesouthern margin of the Cordilleran ice sheet in Washington State, USA over the last two decades has shown more distinct phases of glaciation than previously identified and the importance of large, sudden events in shaping the landscape. This work includes USGS OFR 2009-1033, USGS SIM 3406, and in-progress mapping of the Missoula outburst flood province.

Map units are remotely interpreted from surface shape and position, as distinctions based on material properties (e.g., grain size, degree of leaching), or laboratory analyses (e.g., absolute age) cannot be made from topography alone. Map units are defined by form and position and delineated by inspection of lidar-derived elevation, hillshade, and slope maps. Units are generally process domains, not indistinctly bounded geomorphic ideals: back beach, beach face, and tide flat instead of beach spit; steep hillslope above narrow alluvial flat instead of canyon. Interlocking map-unit polygons cover the entire mapped area without overlap. Map units are empirical and revealed by the topography, not determined by an a priori catalog of possible processes. Recognition of novel textures can lead to discovery of unforeseen processes. Interpretation leans heavily on conservation principles (e.g., where did water come from and where did it go?) and, in glaciated regions, recognition that now-absent ice is required to have—for example—confined ice-marginal drainage. Age relations are mostly discerned by cross-cutting relations (alluvial flat crosscuts glaciated ground) and (or) elevation (lower terraces are younger).

Results from this mapping include recognition that retreat of the Puget lobe of the ice sheet was largely by stagnation (Haugerud, 2021, Geological Society of America Special Paper 548). In the Fraser lowland, high-resolution topography allowed delineation of 7 phases of Sumas glaciation at the end of the last glacial cycle, whereas previous studies had seen 4 phases or fewer. Perhaps the most striking result is the success of the approximation that each part of the landscape was shaped by a unique process over a limited time.  In these landscapes, fluvial erosion and deposition, glacial scour, mass wasting, and other intermittent processes are evidently much more effective than bioturbation, dust deposition, chemical weathering, and other processes that continually rework most parts of most landscapes at most times.  
Geomorphological patterns observed in foredunes under storm and fair-weather conditions revealed by UAV images
Authors: Borges Fernandez Guilherme , de Oliveira Coutinho Ivandro Patrick , Goçalves Pereira Thiago
Published: June 2022

Coastal sandy barriers form a typical environment in wave-dominated coasts. Not rarely, the surface morphology of these features should be interpreted by aeolian sediments, fixed by vegetation, forming foredunes. The morphology observed in the foredunes depends from different processes, related for example the wind speed, wind direction, different types and density of vegetation, variation of wave energy and beach morphodynamics. In this case, some specific geomorphological patterns can be observed in the foredunes, such as blowouts and erosive scarps or even different types of dunes, describe for example by nebkas and parabolic. In the last ten years, the geomorphology experiences a truly revolution by the use of digital photographs obtained by Unmanned Air Vehicles (UAV), where details from the surface were revealed by structure from motion (SfM) photogrammetry. The low-cost and effective results from UAV and SfM provide a high-resolution (centimeters-scale) digital elevation models (DEMs), which allow a more accurate analyses in geomorphology. Using these techniques, the aim of this study is analyzing the morphological characteristics of foredunes submitted by high-energy waves and winds from different directions along Massambaba Beach, southeast Brazil. Massambaba Beach present a more than 50 km of continuous Holocene barrier, classified as stationary barrier. The beach morphodynamic varies from intermediated/reflective on the west side, to intermediated/dissipative in the east. To evaluate the morphological patterns observed by hydrodynamics and aerodynamics effect along the foredunes, we determine changes in the vegetation density by remote sensing, and found that the density decrease from west to the east. After, we select four different areas to survey by UAV. The results showed that the area 1 located in the west Massambaba, the foredunes present disconnected blowouts from the beach, forming a bi-directional parabolic dune, where fair-weather (northeast) and storm winds (south) play an important role. In the central Massambaba the blowouts increase not only in terms of area, but some parabolic dunes can be observed directly connect from the beach, formed by off-shore and onshore winds. In some specific sites, beach scarps eroded the precipitation ridges that reach the berms, and create good conditions for overwash deposits, formed by high-energy waves. The east Massambaba, where we observe the decrease in vegetation density, different types of dunes coexist such as nebkas and parabolic, and the parabolic can be orientated by northeast or southwest depending of prevailed wind. The foredunes in the east Massambaba experience overwash process, which favor washover deposits. We conclude that the morphological complexity observed in the foredunes, revealed by DEM, indicates the importance of these techniques to investigate different process caused by wind and waves. 
Introducing a new and simplified geostatistical-based roughness algorithm
Authors: Trevisani Sebastiano
Published: June 2022

The first aim of this work is to introduce a new geostatistical-based algorithm that permits to detect specific aspects of short-range surface roughness (or of image texture) which does not require user defined choices, except for the radius of the search window, and provides a high interpretability of the results.  In particular, differently from usual geostatistical approaches, this algorithm does not require the derivation of a residual digital elevation model. The new proposed algorithm, despite its simplicity, permits to detect relevant aspects of surface texture, including anisotropy. Moreover, adopting approaches based of digital elevation model smoothing it can also be applied in the context of multiscale analysis. A second aim, functional to the introduction of the new algorithm, is to furnish a general overview of the key aspects of the geostatistical methodologies, highlighting analogies and differences with other approaches. In presenting the algorithm, a comparison with the roughness computed by means of dispersion of vectors normal to surface is performed.

 

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The geodiversity of the Abruzzo, Lazio, and Molise National Park (Central Italy)
Authors: Esposito Gianluca , D'Amico Daniela , Sulli Cinzia , Mancinelli Vania , Paglia Giorgio , Sammarone Luciano , Miccadei Enrico
Published: June 2022

The Abruzzo, Lazio, and Molise National Park is located in the Central Apennines (Italy), in a vast mountainous area of about 1300 km2. It was founded in 1922, and it is renowned for conserving some of the most important Italian fauna species. Moreover, it is an international open-air laboratory for its geological-geomorphological heritage related to various paleogeographical and morphogenetic environments. Great geodiversity examples are still reflected today by the main mountain chains, offering scientists and tourists imaginary journeys through ancient coral atolls and deep blue seas. Valleys of glacial or fluvial origin, alluvial fans, paleolandslides, karst morphologies, and present-day landscapes still preserve the memory of these ancient environments. Here, we report on the methods, initiatives, and activities to improve and valorize Abruzzo, Lazio, and Molise National Park geodiversity. In detail, the enhancement of geoheritage has been widely pursued through a stepwise approach which involved (i) literature data analysis, (ii) census and harmonization of geosites and geomorphosites, (iii) design of thematic maps and visual legends, (iv) geological-geomorphological field surveys. The resulting data allowed us to produce, in strict collaboration with the park managers, innovative tools, such as geoturistic maps and itineraries. These tools are targeted at various potential users (i.e., tourists, residents, young people, schools, and other interested stakeholders) with the final aim to provide the landscape’s observers with a perception of the geological and geomorphological processes within their spatial and temporal scale. The geological heritage, deeply rooted in the area and to date only accessible to a limited number of experts, now needs to be introduced to a broader audience, sensitive to earth and environmental dynamics, and interested in protecting and preserving the territory. The correct classification of geodiversity in the form of geosites and geomorphosites and the evaluation of their vulnerability are fundamental issues in analyzing the relationship between human activity and natural processes involving the landscape.
Effects of topography and geology on vegetation recovery after shallow landslides
Authors: Zhong Chenxi , Oguchi Takashi
Published: June 2022

Shallow landslides are instability events that lead to mass wasting of soil and vegetation in sloping areas and are commonly triggered by intense rainfall. Since vegetation is an important factor influencing the occurrence of rainfall-triggered shallow landslides and reduces the likelihood of landslides through different hydromechanical mechanisms, conducting in-depth research in this field for disaster risk management is meaningful. Investigating vegetation recovery processes after shallow landslides can provide significant insights for improving future disaster habitation works. However, vegetation recovery processes after shallow landslides and their influencing multivariate factors are not well known. Therefore, the objective of this study is to clarify the effects of geology and topography on vegetation recovery after shallow landslides in two research areas, the Shobara district, Hiroshima Prefecture, Japan, and the Obara district, Aichi Prefecture, Japan. Image analysis of historical aerial photographs was used to extract landslide-affected areas. Temporal changes in vegetation-condition indices were accessed from satellite imagery. GIS tools were used to extract topographic and geological indices. The relationships among those factors were quantified using a multivariate analysis of variance. Time series analysis was conducted by using the seasonal autoregressive integrated moving average. The change in time series, climate data, topographic, and geological characteristics were incorporated into a framework for mapping and modeling vegetation recovery. The results have quantitatively revealed both similarities and differences in vegetation recovery between the two areas in relation to geomorphological and geological conditions.
GIS-based machine learning models for assessing landslide impact: A case study in King County, State of Washington, USA
Authors: Lu Di , Oguchi Takashi
Published: June 2022

The impact caused by landslides can be determined by both landslide occurrence probability and the runout distance of landslides. This study aims to evaluate the potential damage caused by landslides in urbanized areas using two different methods: the Artificial Neural Networks (ANNs) method produces a landslide susceptibility map, and the constrained random walk method deals with landslide runout distance. These methods are applied to the study area in King County, Washington, USA. The landslide inventory data used include 2331 historical landslides. We divided each landslide area into the source, transportation, and deposition areas. We also selected 13 conditioning factors for landslide occurrence in the source areas: elevation, slope gradient, slope aspect, plan curvature, profile curvature, lithology, Stream Power Index (SPI), Topographic Wetness Index (TWI), Sediment Transport Index (STI), land cover, distance to roads, distance to railways, and population density. The value of the Area Under the Curve (AUC) of landslide susceptibility assessment using these factors is 0.927, showing the high performance of the applied model. Analysis of the transportation and deposition areas using the random walk model has provided additional insights into landslide hazards.
A general systems approach to mountain geomorphology
Authors: Slaymaker Olav , Leinberger Eric
Published: June 2022

On this 60th. anniversary of Chorley’s paradigm changing paper on geomorphology and general systems theory, the application of his ideas specifically to mountain geomorphology is briefly reviewed. Five kinds of general systems are recognized: (i) morphological systems; (ii) spatio-temporal systems; (iii) water, solute and sediment cascading systems; (iv) mountain process-response systems; and (v) so-called mountain control systems that are actually “out-of-control” systems because of policy and planning failures following intensification of land use and climate change during the Anthropocene epoch. Two examples of research questions under systems categories (iii) and (v) illustrate the value of a general systems approach. The first question concerns the relation between disconnectivity and connectivity and discusses reasons for the comparative neglect of disconnectivity in the recent geomorphological literature. The second question concerns the geomorphological effects of human use of land and associated climate change and discusses reasons for the failure of many policy and planning analysts to recognize the links between human use of land, climate change and  environmental degradation.
Geomorphic Change Caused by Flood at Scott River Alluvial Fan
Authors: Kociuba Waldemar
Published: June 2022

A four-day glacier-melt flood (13-16 August, 2013) caused an abrupt geomorphic change in the proglacial gravel-bed Scott River, that drains the small (10 km2) Scott Glacier catchment (SE Svalbard). This type of floods occur on Svalbard increasingly during periods of abnormally warm or rainy weather in summer or early autumn, and the probability of occurrence grows in direct proportion to the increase in temperature and/or precipitation intensity. In the summer 2013 measurement season, the highest daily precipitation (17 mm) occurred on August 13. During the following four days, it constituted in total 47mm i.e. 50% of the precipitation total for the measurement period of 2013. The largest flood in 20 years, was caused by high precipitation with a synchronous rise in temperature from about 1.0 to 8.6 °C. These values exceeded multi-year averages (32 mm and 5.0 °C, respectively), at average discharge 0.9 m3·s–1 (melt season mean 1986–2011). These conditions caused a rapid and abrupt response of the river with dominant (90%) glacier-fed. The increase of discharge to 4.6 m3·s–1, initiated by the glacial flood, mobilized significant amounts of sediment in the river bed and channel. Geomorphic changes within the alluvial fan as area of 58,820 m2, located at the mouth of the Scott River, were recorded by multi-sites terrestrial laser scanning using a Leica Scan Station C10, and then estimated using Geomorphic Change Detection (GCD) Software. Flood-induced total area of lowering (erosion) covered 38% of the alluvial fan (6,030 m2), resulting in the removal of 1,182 ± 121 m3 of sediment volume. During the final phase of the flood, two times more sediments (1,919 ± 344 m3) was re-deposited within the alluvial fan surface, causing significant aggradation on 62% of its area (17,190m2). These geomorphic changes resulted in an average lowering (erosion) of the alluvial fan surface of 0.2 m and an average rising (deposition) of 0.1 m.
Hydrosedimentological study of a covered fluviokarst in the Brazilian Cerrado
Authors: Uagoda Rogerio , Hussain Yawar , Caldeira Dandara , Moraes Nogueira Adivane , Fonseca Maria Rita , da Silva Tavares André
Published: June 2022

The studied region located in the Rio Vermelho watershed, situated at the foot of the Serra Geral de Goiás in the Brazilian Cerrado, hosts a covered fluviokarst system containing ~150 mapped caves that capture the rivers (sediment loads) upstream. The present study aims at developing a better understanding of the geomorphological controls, considering the impacts of climatic conditions and land use types on the production and transport of the sediments to the caves using an integrated approach (GIS mapping, hydrosedimentological monitoring, and geochronological analysis).

The preliminary results indicate the influence of two sites on sediment production: a) downstream, constituted by the karstic system developed in the Neoproterozoic carbonates (Bambuí group), where the soils are occupied by natural vegetation or pastures (family farming), and, b) upstream, on a plateau, which supplies water to the karstic system, with soils developed on Cretaceous sandstones (Urucuia group), the areas of growing mechanized agriculture. Models of the upper and lower fluviokarst systems are developed using the soil types and recharge zonation information. The chronology of the preserved sedimentary deposits, formed by the alternation of clayey and sandy facies, has been established, between 60ky and 200ky in the upper cavities and up to 20 ky in the fluviokarst blind valleys. Hydrosedimentological monitoring revealed the production of ~ 9 Mg ha-1yr-1 of sediments from degraded soils, while 2.0 Mg ha-1yr-1 are produced from soils having received the conservation protocol, a lower value than the geological rate as established in the literature. The sediments transported in the karst are poorly sorted compared to those in the rivers and an increase in the particulate load during floods (<7 against ~500 mg/L).

There is still a lack of evidence about the origin of the water and sediments circulating in this karst system. Further studies on fresh sedimentary deposits in the recent sinkholes may help to better quantify recent paleo-environmental modifications and the effects of anthropogenic activities upstream.

Keywords: GIS; Geochronology; Blind valleys; C14;  Fluviokarst
Ornithogenic soil genesis by flying birds in Maritime Antarctica: the role of landforms in the nests establishment
Authors: Oliveira Fábio , Rodrigues William , Scahefer Carlos Ernesto , Leite Maringela
Published: June 2022

This research was conducted to evaluate the contribution of landforms in establishing Giant petrels (G. petrels) and Brown skuas (B. skuas) nesting and the formation of ornithogenic soils by the phosphatization process in Harmony Point, Maritime Antarctic. Ten nests from the coastal domain (marine terrace) and the cryoplanated platform were selected to collect topsoil samples (0-20 cm). The samples were collected from 0 m up to 20 m in each nest, with regular spacing of 2 m. The analysis of the samples included the physical, chemical, mineralogical, and geochemical analyses. The pH acidity found in the topsoils is similar to the phosphatized soils in penguins. Phosphate minerals such as apatite, leucophosphite, and vivianite were identified. The high content of some trace elements, such as Zn, Cu and Sr is associated with the bird’s excrements.  Total-P recorded higher levels in the cryoplanated platform, while higher levels of bioavailable-P were observed in the marine terrace. This result demonstrates the importance of the landforms in the bird’s nesting, as well as in the development of the soil in these soil-forming environment. Phosphatization in these areas is not restricted to the specific location of the nest since high values of P have been identified at distances between 8 and 12m, from de nest’s top. This suggests the transport of P-rich solutions and phosphatized material along with fractures by the freeze-thaw cycles, depositing these materials 20 m away, contributing to increasing the geographical expression of this phenomenon in this ice-free area, consequently the development of soils and the establishment of vegetation.
Morphostructural mapping of the Manamas Mountain, a Banda Arc fragment overthrusting on the Australian Continental Margin (Oecusse, Timor-Leste)
Authors: Lopes Fernando Carlos , Pratas João , Vicente Victor
Published: June 2022

Timor island is located north of Australian Continent and is one of the southeasternmost Sunda islands. In a tectonic context, is located at the collisional margin between the oceanic Banda volcanic arc and the Australian continental margin. The island does not have a volcanic nature and is made up of three main tectonostratigraphic sequences : i) Australia Affinity Sequence, that comprises units whose ages range from the Upper Carboniferous to the Late Miocene, deposited on Australian continental or transitional continental crust prior to collision with the Banda Terrane; ii) Banda Arc Terrane Sequence, that comprises the allochthonous forearc units of the Banda volcanic arc and are of Asia affinity. They span from Jurassic to Pliocene in age; iii) Banda Orogen Sequence, consisting of units that have formed or been deposited since the start of collision of the continental margin with the Banda forearc, ages spanning from upper Miocene to present.

The Manamas Mountain is an elevated region located in the northeast sector of the Timor-Leste Oecusse enclave, largely built up of volcanic rocks of Late Miocene age (Manamas Formation; Banda Arc Terrane Sequence). It may represent a fragment of the Banda Arc overthrusting on the northernmost edge of the Australian continental margin.

Recognition of the main structural lineament systems of the Manamas Mountain and definition of its main morphostructural characteristics to complement structural and geological mapping are the main goals of the present study, which aims to determine such aspects through interpretation of spatial remote detection digital data acquired by the Landsat satellite's sensor (ETMþ) and the Earth satellite's sensor (Aster) and aerial orthophoto maps.
Sediment mobility recovery experiences: dam removal and sediment transfer through dams
Authors: Ibisate Askoa , García J. Horacio , Ollero Alfredo , Ferrer Carles , Vázquez-Tarrio Daniel , Martín Vide Juan Pedro , Sánchez-Pinto Iban , Herrero Otero Xabier , Ortiz Josu
Published: June 2022

Dams, weirs and other transversal obstacles limit sediment transport. River restoration seeks the recovery of river processes and functions. Rivers need water, sediment and space. In this work we present a couple of examples of sediment transport recovery and monitoring. One of them was implemented through the removal of a dam and the second one through sediment transfers downstream a dam.

Dam removal allows the recovery of the longitudinal connectivity of rivers, facilitating water and sediment transfer. In Leitzaran River (Basque Country, Spain) bedload sediment transport was monitored from 2016 to 2022 in a reach of river affected by the Oioki dam, 7-meters high. The removal, funded through a LIFE project, started in 2018 with the first 3 meters of the dam, and was completed in 2019 with the remaining 4 meters. RFID technique was used for the monitoring. 300 tagged particles were introduced each year, 100 in each subreach (control, upstream the dam and downstream), 1800 in total. Each summer an intensive field work campaign searching these tags has been conducted. This long monitoring has given results of the sediment transport in different conditions, before removal, during partial removal and after complete removal. Once the dam is completely removed an important increase of the volume of mobilized sediment both in the upstream and downstream reaches is given. The mobilization of sediment is more a question of availability and change of river conditions, opening of a barrier and base level change, more than flows, as it was registered in the most discreet hydrological year of all the monitoring period.

In active hydroelectrical stations,, where removal is not an option, sediment transport recovery could be implemented differently. In Viar River, a tributary of Guadalquivir (Spain), is a completely clogged counter reservoir where the electrical company (ENDESA) needs to withdraw sediment to increase volume and pump it back to El Pintado reservoir for reversible hydroelectrical generation. Guadalquivir basin authorities require giving it back to the river instead of bringing to a dump. In 2021 autumn 700 m3 of sediment were withdraw from a deposit and located upstream the counter reservoir dam, terrain characteristics are difficult and do not allow downstream mechanical transfer. The clogged reservoir would allow the auto-transfer by the river. The goal is to propose an auto-transfer system, studying the critical flow and creating flow conditions from upstream reservoir to allow sediment movement and transfer, recovering environmental conditions and avoiding reservoir clogging.