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The Ili‐Balkhash region in southeastern Kazakhstan hosts morphologically diverse dormant desert dune fields and presents an interesting opportunity for geomorphological and palaeoenvironmental studies. Because the morphology of aeolian dunes is primarily driven by wind dynamics, the dormant dunes in the study area may reflect past wind conditions. We assess their concurrence with modern ERA5 wind data to test whether there has been a change in wind regime since the dunes' last phase of activity. Our approach includes dune mapping, the quantification of dune orientations, the modelling of modern bedform orientations, and optically stimulated luminescence (OSL) dating for temporal context. The centrepiece of our methodological contribution is a novel semi‐automated mapping workflow using geographic object‐based image analysis (GEOBIA) and machine learning (ML) on Sentinel‐2 satellite imagery. Within the scope of a case study, we map dune fields in the Ili‐Balkhash region and quantify dune orientations. We further apply the maximum gross bedform‐normal transport (MGBNT) concept to model bedform orientations matching modern wind regimes for each of the sites. We find that strong winds show better alignment with observed dune orientations than wind regimes comprising all wind speeds. Furthermore, bedform orientations in some of our study sites, namely those that are located in the open plain southeast of Lake Balkhash, do not reflect modern winds. The divergence between dune orientations and wind regime suggests changes in local wind dynamics since the dune fields' last phase of activity. [ABSTRACT FROM AUTHOR]

Many studies of Earth surface processes and landscape evolution rely on having accurate and extensive data sets of surficial geologic units and landforms. Automated extraction of geomorphic features using deep learning provides an objective way to consistently map landforms over large spatial extents. However, there is no consensus on the optimal input feature space for such analyses. We explore the impact of input feature space for extracting geomorphic features from land surface parameters (LSPs) derived from digital terrain models (DTMs) using convolutional neural network (CNN)‐based semantic segmentation deep learning. We compare four input feature space configurations: (a) a three‐layer composite consisting of a topographic position index (TPI) calculated using a 50 m radius circular window, square root of topographic slope, and TPI calculated using an annulus with a 2 m inner radius and 10 m outer radius, (b) a single illuminating position hillshade, (c) a multidirectional hillshade, and (d) a slopeshade. We test each feature space input using three deep learning algorithms and four use cases: two with natural features and two with anthropogenic features. The three‐layer composite generally provided lower overall losses for the training samples, a higher F1‐score for the withheld validation data, and better performance for generalizing to withheld testing data from a new geographic extent. Results suggest that CNN‐based deep learning for mapping geomorphic features or landforms from LSPs is sensitive to input feature space. Given the large number of LSPs that can be derived from DTM data and the variety of geomorphic mapping tasks that can be undertaken using CNN‐based methods, we argue that additional research focused on feature space considerations is needed and suggest future research directions. We also suggest that the three‐layer composite implemented here can offer better performance in comparison to using hillshades or other common terrain visualization surfaces and is, thus, worth considering for different mapping and feature extraction tasks. Plain Language Summary: Characteristics of the land surface, such as steepness, relative slope position (e.g., ridge vs. valley), and roughness, can be digitally represented using a variety of methods. These digital representations, along with human‐annotated labels, can be provided to artificial intelligence algorithms to generate maps of landforms, such as those associated with river systems, glaciers, or human‐induced changes to the landscape. Given the large number of terrain derivatives that can be generated from digital elevation data, it is unclear how the chosen inputs impact the utility of the resulting maps. This study suggests that artificial intelligence mapping algorithms are sensitive to representations provided to them since different inputs resulted in varying map accuracies. We suggest a combination of features, which collectively describe relative slope position, steepness, and local terrain texture, as a means to represent the landscape and to serve as input to artificial intelligence algorithms. Our results can make it easier to train artificial intelligence algorithms to consistently and objectively find surficial features of interest across large swaths of Earth's surface. Key Points: We test the sensitivity of convolutional neural network geomorphic feature extraction approaches to the input feature spaceA three‐layer composite incorporating slope and topographic position index outperformed common inputs like hillshades and slopeshadesResults held true across four use cases including both natural and anthropogenic landforms [ABSTRACT FROM AUTHOR]

Future climate projections indicate an expansion of the world’s drylands, and with that a commensurate increase in the mobilization of unconsolidated desert sediments such as sand and dust. It is therefore increasingly important to investigate the large-scale formation of dryland landscapes such as dunefields in order to better understand the processes responsible for their genesis, evolution, and thresholds for mobilization. Assessing dunefield morphologic variability, including analysis of the morphologic relationship between aeolian bedforms and other landforms such as fluvial channels and bedrock uplands, underpins such investigations. So far, however, meaningful investigations of erg-scale geomorphic patterns have been limited. This is in part due to the technological limitations of geographic information system (GIS) tools, particularly in the case of open-source datasets and software, which has effectively hindered investigations by colleagues in drylands of the global south where many of the world’s dunefields are located. Recent years have overseen the increasing availability of open-source remote sensing datasets, as well as the development of freely available software which can undertake geographic object-based image analysis (GEOBIA). These new tools facilitate cartography and statistical analysis of dunefields at large scales. In this study we make use of open-source GIS to characterise a morphologically diverse linear dunefield southwest of Kati Thanda (Lake Eyre) in central Australia. We focus on three parameters; dune orientation, spacing and Y-junctions using semi-automated GEOBIA, and investigate these in the context of local fluvial channels, depressions (pans) and uplands. Our results suggest a possible correlation between dune orientation, wind regime and the role of uplands as deflective barriers to longitudinal dune migration; dune spacing and sediment supply, likely relating to the location of both ephemeral and abandoned fluvial channels; and Y-junction frequency with underlying topography. Our study provides a framework for understanding process-based interactions between dunes and other landforms, as well as the first completely open-source approach which can be applied to linear dunefields worldwide.

Remote sensing is a relevant method to map inaccessible areas, such as intertidal mudflats. However, image classification is challenging due to spectral similarity between microphytobenthos and oyster reefs. Because these elements are strongly related to local geomorphic features, including biogenic structures, a new mapping method has been developed to overcome the current obstacles. This method is based on unmanned aerial vehicles (UAV), RGB, and multispectral (four bands: green, red, red-edge, and near-infrared) surveys that combine high spatial resolution (e.g., 5 cm pixel), geomorphic mapping, and machine learning random forest (RF) classification. A mudflat on the Atlantic coast of France (Marennes-Oléron bay) was surveyed based on this method and by using the structure from motion (SfM) photogrammetric approach to produce orthophotographs and digital surface models (DSM). Eight classes of mudflat surface based on indexes, such as NDVI and spectral bands normalised to NIR, were identified either on the whole image (i.e., standard RF classification) or after segmentation into five geomorphic units mapped from DSM (i.e., geomorphic-based RF classification). The classification accuracy was higher with the geomorphic-based RF classification (93.12%) than with the standard RF classification (73.45%), showing the added value of combining topographic and radiometric data to map soft-bottom intertidal areas and the user-friendly potential of this method in applications to other ecosystems, such as wetlands or peatlands. [ABSTRACT FROM AUTHOR]

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The sand islands and shore-attached dune fields of south east Queensland form the world’s oldest and largest coastal sand dune system. Here we present updated morphological maps for the dune fields based on topographic expression and geomorphic relationships. Individual dunes were delineated using high-resolution elevation data and were grouped into morphosequences based on the elevation, drainage characteristics and slope characteristics of the individual dunes. The slope characteristics focussed on high resolution derived slope-curvature and slope-elevation parameters. Morphosequences were recognised from cross-cutting relationships and relative position in the dune field. Our method was developed for the Cooloola Sand Mass and then applied to Fraser Island, Moreton Island and North Stradbroke Island, the other major sand islands in south east Queensland. In total, five Holocene and four Pleistocene units have been identified. The new mapping underpins current work on the geomorphic evolution of the dune fields.

It was thought for a long time that only the younger and tectonically active mountains are prone to landslides and hence more attention was given in studying them the world over. But, when the landslides have started occurring in other mountain regions of high rainfall and human interventions also, these mountains too came under the purview of landslide studies. The studies thus widened to the other mountains revealed that the various geological/terrain parameters and the degree of anthropogenic activities occur in different combinations and assign varying grades of landslide probabilities. According to it, these mountains succumb to different degrees of landslides when heavy rainfall occurs. The state of Kerala, which is 600 km long in North Northwest–South Southeast and 35 to 120 km broad in East-West directions, is one such a region of recurring landslides. It is a unique physiographic/geomorphic province with highly elevated NNW-SSE oriented Western Ghat Mountains in the east, that are rimmed by the sub parallel systems of landforms like composite slopes, marginally raised lateritic uplands and the coastal plains successively in the west with gradual descending elevation, thus providing a step like topography. The regular annual rainfall of the southwest monsoons cause devastating landslides in Kerala due to the unique geomorphic setting. So the present study was carried out to analyse the geomorphology of the region in details, which is dominantly evolved by the tectonics, to elucidate its input over the landslides. In the study, the geomorphic features were studied in detail using the (i) satellite false colour composite imagery wrapped over the digital elevation model of the terrain, (ii) shaded relief maps and (iii) the topographic cross sections drawn over the above satellite data wrapped 3D terrain model. These were accomplished using the advanced options available with geospatial technology. The study revealed that due to the high degree of deformation and the resultant development of geomorphology of the study area, the rainwater infiltrates and cause landslides in the form of rock and cliff topples, rock and cliff falls, landslides, talus and debris falls/flows. [ABSTRACT FROM AUTHOR]

Rock avalanches are low frequency natural hazards that can alter landscape morphology, and constraining the timing, volume and emplacement dynamics of pre-historic rock avalanches is crucial for understanding the hazards posed by these events. Here we perform cosmogenic nuclide dating, topographic reconstruction and runout modeling of the Molveno rock avalanche, located north of Lake Garda in the Province of Trento, Italy. The unique morphology of the deposits, which features numerous large scarps and prominent lineaments, have previously led researchers to interpret the Molveno rock avalanche as being the result of multiple events. Our results show that the Molveno rock avalanche had a volume of approximately 600 Mm3, and failed from a prominent niche located on Monte Soran. 36Cl cosmogenic nuclide dating results shows that the deposits were emplaced as a single event approximately 4.8 ± 0.5 ka, and suggests that the unique deposit morphology is due to the emplacement processes acting during and soon after failure. Numerical runout modeling shows that this morphology could have resulted from a combination of runup and extensional spreading of the debris along the complex valley floor topography. The ages we determined for this event are coincident with the nearby Marocca Principale rock avalanche (5.3 ± 0.9 ka), which may suggest a common trigger. Our results have important implications for interpreting the morphology of rock avalanche deposits, and contribute to the evolving understanding of rock avalanche processes in the Alps.

The main advantage of using interdisciplinary research methods is that new approaches and insights regarding the interractions between past communities and landforms may be performed. The main aim of this paper is to assess by using high quality archaeological record data and high resolution LIDAR support the connection between Roman archaeological sites and fluvial geomorphic frame. The study area is represented by Timiș Valley between Caransebeș and Lugoj, in the Southwest of Romania, part of the former Roman province of Moesia Superior. Thus, the paper is divided into two main sections. The first one is represented by the mapping of the fluvial landforms. High resolution LIDAR support, aerial photography and topographical maps were used in geomorphic mapping. This first step focused on fluvial landforms (valley margin, terraces, meadows, alluvial fans, transition areas etc.). Secondly, a total number of 37 Roman archaeological sites were mapped and overlapped on the fluvial landforms. Proximity and spatial analysis operations were performed. We believe that the results highlights an unexpectedly significant connection between the Roman sites and the fluvial geomorphic frame. These results have also strenghtened our innitial presumptions regarding the importance of relief in Antiquity in the Southwest of Romania. [ABSTRACT FROM AUTHOR]

River floodplains constitute an important element in the terrestrial sediment and organic carbon cycle and store variable amounts of carbon and sediment depending on a complex interplay of internal and external driving forces. Quantifying the storage in floodplains is crucial to understand their role in the sediment and carbon cascades. Unfortunately, quantitative data on floodplain storage are limited, especially at larger spatial scales. Rivers in the Scottish Highlands can provide a special case to study alluvial sediment and carbon dynamics because of the dominance of peatlands throughout the landscape, but the alluvial history of the region remains poorly understood. In this study, the floodplain sediment and soil organic carbon storage is quantified for the mountainous headwaters of the River Dee in eastern Scotland (663 km2), based on a coring dataset of 78 floodplain cross‐sections. Whereas the mineral sediment storage is dominated by wandering gravel‐bed river sections, most of the soil organic carbon storage can be found in anastomosing and meandering sections. The total storage for the Upper Dee catchment can be estimated at 5.2 Mt or 2306.5 Mg ha‐1 of mineral sediment and 0.7 Mt or 323.3 Mg C ha‐1 of soil organic carbon, which is in line with other studies on temperate river systems. Statistical analysis indicates that the storage is mostly related to the floodplain slope and the geomorphic floodplain type, which incorporates the characteristic stream power, channel morphology and the deposit type. Mapping of the geomorphic floodplain type using a simple classification scheme shows to be a powerful tool in studying the total storage and local variability of mineral sediment and soil organic carbon in floodplains. © 2019 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The sand islands and shore-attached dune fields of south east Queensland form the world’s oldest and largest coastal sand dune system. Here we present updated morphological maps for the dune fields based on topographic expression and geomorphic relationships. Individual dunes were delineated using high-resolution elevation data and were grouped into morphosequences based on the elevation, drainage characteristics and slope characteristics of the individual dunes. The slope characteristics focussed on high resolution derived slope-curvature and slope-elevation parameters. Morphosequences were recognised from cross-cutting relationships and relative position in the dune field. Our method was developed for the Cooloola Sand Mass and then applied to Fraser Island, Moreton Island and North Stradbroke Island, the other major sand islands in south east Queensland. In total, five Holocene and four Pleistocene units have been identified. The new mapping underpins current work on the geomorphic evolution of the dune fields. [ABSTRACT FROM AUTHOR]

Temperate Highland Peat Swamps on Sandstone (THPSS) and Coastal Upland Swamps in the Sydney Basin (CUSSB) are listed as endangered ecological communities under Australia's national and state legislation. They are threatened by a range of human and climate impacts. Across the region there are 3208 individual, valley-bottom, elongate-shaped, upland swamps that drain first- or second-order drainage lines and small catchment areas (mean = 0.25 km2). They occur at a median distance of 57 km from the coast in areas with an average annual rainfall of 1505 mm/year and average annual temperature of 15°C. Those closer to the coast occur on elevations as low as 160 m a.s.l., and those further from the coast, on plateau country, occur up to 1172 m a.s.l. (median 634 m a.s.l.). The valleys that contain these swamps terminate downstream at a valley constriction or bedrock step, behind which alluvial materials have accumulated, and peat has formed to produce relatively steep swamps (median slope 6.2 per cent). Understanding the spatial distribution and physical attributes of these systems, and having the accompanying maps as a resource, is critical for development of sound, well-informed conservation, rehabilitation and monitoring programs, and for analysing the ecosystem services they provide. [ABSTRACT FROM AUTHOR]

Alpine landscapes are typically characterized by inherited features of past glaciations and, for the more recent past, by the interplay of a multitude of types of geomorphic processes, including permafrost creep, rockfalls, debris flows, and landslides. These different processes usually exhibit large spatial and temporal variations in activity and velocity. The understanding of these processes in a wide alpine area is often hindered by difficulties in their surveying. In this study, we attempt to disentangle recent changes in an alpine landscape system using geomorphic mapping and L-band DInSAR analyses (ALOS-PALSAR) in the Zermatt Valley, Swiss Alps. Geomorphic mapping points to a preferential distribution of rock glaciers on north-facing slopes, whereas talus slopes are concentrated on south-facing slopes. Field-based interpretation of ground deformation in rock glaciers and movements in talus slopes correlates well with the ratio of InSAR images showing potential ground deformation. Moraines formed during the Little Ice Age, rock glaciers, and talus slopes on north-facing slopes are more active than landforms on south-facing slopes, implying that the presence of permafrost facilitates the deformation of these geomorphic units. Such deformations of geomorphic units prevail also at the elevation of glacier termini. For rock cliffs, the ratio of images indicating retreat is affected by slope orientation and elevation. Linkages between sediment supply from rock cliffs and sediment transport in torrents are different among tributaries, affected by relative locations between sediment supply areas and the channel network. We conclude that the combined use of field surveys and L-band DInSAR analyses can substantially improve process understanding in steep, high-mountain terrain. [ABSTRACT FROM AUTHOR]

A key skill that geomorphologists possess is the ability to use multi‐scale perspectives in their interpretations of landscapes. One way to gain these perspectives is with the use of nested hierarchical frameworks. In fluvial geomorphology, such frameworks help with assessment of large‐scale controls (e.g., tectonic activity, climate change) on the pattern and dynamics of smaller‐scale physical features (e.g., channels, floodplains, bars), and conversely illustrate how these smaller‐scale features provide the building blocks from which to make interpretations of fluvial processes and dynamics over larger spatial and temporal scales. Given the rapid pace of technological developments, the range of relatively inexpensive tools available for visualising and mapping landscapes at different spatial scales is expanding exponentially. In this paper, which focuses on the World Heritage‐listed Okavango Delta in Botswana, we demonstrate how various visualisations generated by different technologies at different spatial scales (catchment, landscape unit, reach, site and geomorphic unit) are providing critical baseline information to enhance interpretation and communication of fluvial geomorphology, with potential application in water resources management. In particular, our nested hierarchical approach could be used as an interactive communication tool for non‐specialists and embedded within existing and future management plans for the Delta. The construction of nested hierarchies that synthesise information and analyses can be a valuable addition to the environmental manager's toolkit. [ABSTRACT FROM AUTHOR]

Descriptions of the Cordilleran Ice Sheet retreat after the last glacial maximum have included short-lived readvances occurring during the Older and Younger Dryas stadial periods and into the Holocene, but identification of these events has been largely limited to southwest and central British Columbia and northwest Washington State. We present evidence of a late Pleistocene readvance of Cordilleran ice occurring on the central coast of British Columbia on Calvert Island, between northern Vancouver Island and Haida Gwaii. Evidence is provided by sedimentological and paleoecological information contained in a sedimentary sequence combined with geomorphic mapping of glacial features in the region. Results indicate that a cold climate existed between 15.1 and 14.3 cal ka BP and that ice advanced to, and then retreated from, the western edge of the island between 14.2 and 13.8 cal ka BP. These data provide the first evidence of a major fluctuation in the retreating ice sheet margin in this region and suggest that a cold climate was a major factor in ice readvance. These data contribute to the understanding of past temperature, ice loading and crustal response, the nature of ice margin retreat, and the paleoenvironment of an understudied area of the Pacific Northwest. [ABSTRACT FROM AUTHOR]

Mapping regional spatial patterns of coral reef geomorphology provides the primary information to understand the constructive processes in the reef ecosystem. However, this work is challenged by the pixel-based image classification method for its comparatively low accuracy. In this paper, an object-based image analysis (OBIA) method was presented to map intra-reef geomorphology of coral reefs in the Xisha Islands, China using Landsat 8 satellite imagery. Following the work of the Millennium Coral Reef Mapping Project, a regional reef class hierarchy with ten geomorphic classes was first defined. Then, incorporating the hierarchical concept and integrating the spectral and additional spatial information such as context, shape and contextual relationships, a large-scale geomorphic map was produced by OBIA with accuracies generally more than 80%. Although the robustness of OBIA has been validated in the applications of coral reef mapping from individual reefs to reef system in this paper, further work is still required to improve its transferability. [ABSTRACT FROM AUTHOR]

• A cross-disciplinary method quantifies river biogeomorphic succession phases at the reach scale. • A trial application shows that Biogeomorphic landform ratios effectively differentiate phases of river evolution. • The approach is generic and can be used in different situations. The Fluvial Biogeomorphic Succession phase model (FBS model) differentiates Geomorphic (G), Pioneer (P), Biogeomorphic (B) and Ecological (E) phases of hydro-geophysical-biological interactions in river systems. To date, quantitative applications of this model have been restricted to field surveys of vegetation composition analysis at the patch-scale. Here we develop a biogeomorphic landform mapping approach to determine the dominant biogeomorphic succession phase at the reach scale. We categorize river morphology into four biogeomorphic landform types (G-, P-, B- and E-landforms) that have particular geomorphic, substrate and vegetation cover characteristics. Ratios of these landforms are used to calculate the dominant succession phase in a given reach. A test of this method conducted for two contrasting anabranching reaches of the Upper Yellow River indicates that landform ratios provide an efficient and reliable approach to assess river biogeomorphic succession phase. The approach can be adapted to support systematic cross-scalar analyses across the range of river environments. [ABSTRACT FROM AUTHOR]

A denudation level is a well-known and widely used concept to understand landform evolution, which became one of the benchmarks of geomorphology in the last century. But there is still a question: how can we use formerly described denudation levels to identify the main stages of surface development? The literature abounds in methods to measure the absolute age or determine the relative age of denudation levels, but these methods are expensive or cannot be used in the Western Mecsek Mountains due to the lack of correlative sediments. A revision of the established ages and origin of denudation levels based on the recent geomorphic theories is also needed. In this paper we revise the formerly published geomorphic maps as well as local and antiquated terminology on the denudation levels of the Western Mecsek Mountains, using classical geomorphic interpretation supported with GIS. Three denudation levels were mapped and their relative age was determined based on the comparison of their altitudinal relations and the revision of data from previously published papers. These denudation levels, even if reshaped, represent the Early to Late Miocene and Early Pleistocene phases of surface development. Therefore, the review of the relative age of denudation levels helps summarize our knowledge on the surface development in the Western Mecsek Mountains and it can be the base for further geomorphic studies. We expect these data will become a rich source of information to other researchers studying denudation levels of the Carpathians and the Carpathian Basin. [ABSTRACT FROM AUTHOR]

In river valleys, both human occupation and subsequent preservation of archaeological sites are affected by active landscape transformation caused by river lateral migration, incision/aggradation cycles and changes of river hydrological regime. In the middle Vychegda River valley (Northern Russia), there are numerous traces of human presence since the Mesolithic. We exploit multi-disciplinary archaeological, geomorphological and geochronological approach to elucidate the environmental preferences of settlements positioning during different epochs of the Holocene. High resolution space image supplemented with data on alluvial stratigraphy derived from bank exposures and hand cores, as well as 51 radiocarbon dates were used to make the geomorphic map showing ages of floodplain/terrace segments and palaeochannels. Using this map together with sediment facial interpretation, position of archaeological sites was analysed in the context of local geomorphic and hydrologic situation. The majority of archaeological sites and modern settlements are found on terraces at river banks or at oxbow lakes which were well connected to the river. Few exceptions from this rule may be explained by seasonal character of dwelling functioning, ritual burial practice or specialization of settlements. Geomorphic situation was used as a background for planning further prospection of different-age archaeological objects. [ABSTRACT FROM AUTHOR]

Abstract: Linear dunefields dominate the arid centre of the Australian continent. The morphological variability of linear dunes in the Strzelecki and Tirari Deserts of Australia was assessed using a dune classification scheme based on quantifiable variables of substrate, spacing and junction frequency. The use of high spatial resolution ASTER satellite imagery enabled detailed analysis, including spectral characterisation of substrate, at both local and regional scales. The classification of the linear dunes revealed close relationships between substrate type and dune spacing, reflecting local sediment availability. Increasing dunefield organisation downwind is reflected in reduced numbers of dune junctions, and may suggest the attainment of dynamic morphological and sedimentological equilibrium. Both downwind evolution and sediment nourishment from local sources play a role in linear dune formation. Maps illustrating the spatial distribution of planimetric variables provide a useful tool for investigating linear dune behaviour, although additional variables such as height and dunefield age add to the complexity of dune formation and must also be considered. [Copyright &y& Elsevier]

Abstract: Debris flows are a major threat in many parts of the Alps, where they repeatedly cause severe damage to infrastructure and transportation corridors or even loss of life. Nonetheless, the spatial behavior of past debris-flow activity and the analysis of areas affected during particular events have been widely neglected in reconstructions so far. It was therefore the purpose of this study to reconstruct spatio-temporal patterns of past debris flows on a forested cone in the Swiss Alps (Bruchji torrent, Blatten, Valais). The analysis of past events was based on a detailed geomorphic map (1:1000) of all forms related to debris flows as well as on tree-ring series from 401 heavily affected trees (Larix decidua Mill. and Picea abies (L.) Karst.) growing in or next to deposits. The samples were analyzed and growth disturbances related to debris-flow activity assessed, such as tangential rows of traumatic resin ducts, the onset of reaction wood or abrupt growth suppression or release. In total, 960 growth disturbances were identified in the samples, belonging to 40 different event years between A.D. 1867 and 2005. In addition, the coupling of tree-ring data with the geomorphic map allowed reconstruction of eleven formerly active channels and spatial representation of individual events. Based on our results we believe that before 1935, debris flows preferentially used those channels located in the western part of the cone, whereas the eastern part of the cone remained widely unaffected. The spatial representation of the 40 events also allowed identification of five different spatial patterns for debris flows at the study site. [Copyright &y& Elsevier]

Past landslides have been recognized in the Battice area in E-Belgium. In contrast to the other inactive landslides, the Manaihan landslide responded immediately to heavy rainfall events in the last two decades. This study aims to map its spatial extent and the dominant surface features; to measure surface displacement using GPS; to investigate subsurface structure with Cone penetration test (CPT) and corings; and to determine the depth of the shear surface by inclinometers. Results show a partial landslide reactivation. Surface velocities range between 20 and 40 cm/year and are strongly dependent on winter rainfall. CPT results give clear boundaries between the landslide mass and the undisturbed bedrock in the head scarp. Distinct shear surfaces have been determined with displacement rates up to 15.8 mm in 21 days. Further research should apply geophysical methods for two-dimensional information on the ground, investigate geotechnical properties of the landslide mass, model slope instability, and determine the influence of a sewage pipe crossing the central landslide mass as a potential cause for landslide activity. [ABSTRACT FROM AUTHOR]