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New analytical landslide velocity solutions are unified with existing solutions, provide a complete picture of landslide with accelerating & decelerating movements through entire track. Initially ascending & descending fronts result in strikingly contrasting deposition lengths. Time & space evolution with initial peaks of variable strengths lead to a spectacular propagation pattern. Numerical solutions can be replaced by cost-effective, analytical solutions, offering great practical advantages.

We investigated the influence of sediment transport modes on the formation of bedforms using theoretical analysis. The results of the theoretical analysis were verified with published data of plane beds obtained by fieldwork and laboratory experiments. We found that suspended sand particles can promote the formation of plane beds on a fine-grained bed, which suggests that the presence of suspended particles suppresses the development of dunes under submarine sediment-laden gravity currents.

This study presents a method to calculate the retreat of the sea-cliffs and the volume of rock eroded by the sea on volcanic islands, by reconstructing their pre-erosion shape and size. The method has been applied on Corvo Island (Azores). We show that before the island was eroded, it was roughly 8 km wide and 1 km high. The island has lost more than 6 km³ of rock and 80 % of its surface. We also show that the erosion of sea-cliffs is mainly due to the moderate and most frequent waves.

Landscape Evolution Models allow us to simulate the way the Earth’s surface is shaped and help us understand relevant processes, in turn helping us to manage landscapes better. The models typically represent the land surface using a grid of square cells of equal size, averaging heights in those squares. This study shows that the size chosen by the modeller for these grid cells is important, with larger sizes making sediment output events larger but less frequent.

Arctic river deltas influence how nutrients and soil organic carbon, carried by sediments from the Arctic landscape, are retained or released into the Arctic Ocean. Under climate change, the deltas themselves and their ecosystems are becoming more vulnerable. We build upon previous models to reproduce for the first time an important feature seen in all Arctic deltas, and simulate its future under a warming climate. This can impact the future of Arctic deltas and the carbon release they moderate.

To understand landscape evolution in the mineral resource-rich Yukon River basin (Alaska and Canada), we mapped and cosmogenic isotope-dated river terraces along the Charley River. Results imply widespread Yukon River incision that drove increased Bering Sea sedimentation and carbon sequestration during global climate changes 2.6 and 1 million years ago. Such erosion may have fed back to late Cenozoic climate change by reducing atmospheric carbon as observed in many records worldwide.

In long-lived areas, relief rejuvenation can be greatly controlled by both the geometry of reactivated structures and the kinematics setting. We have applied geomorphological qualitative analyses, geomorphic index and knickpoints modelling to detect Quaternary reactivation of fractures in the Betics foreland (southern Spain). The obtained relief rejuvenation pattern and fault kinematics agree with propagation of transpressional deformation from the Betics fold and thrust belt.

Here we use two different datasets to inform a process-based model to study coastal cliff retreat rates across the past 7000 years at four different chalk coast sites across the south coast of England. Our results demonstrate how a simplified model can not only capture long-term trends in cliff retreat rates, which are linked to the rate of sea level rise, but also identify key erosion processes at real-world sites with contrasting rock types.

The Flims area in the Swiss Alps has fascinated the researchers with its complex geological history ever since. Especially the order of events related to the Tamins and Flims rockslides has long been debated. This paper presents novel results based on up to 160 m deep geophysical profiles, which show onlaps of the Bonaduz Gravel onto the Tamins deposits (Ils Aults) and thus indicate that the Tamins rockslide occurred first. The consecutive evolution of this landscape is shown in four phases.

The presented automatic deadwood generator (ADG) allows us to consider deadwood in rockfall simulations in unprecedented detail. Besides three-dimensional fresh deadwood cones, we include old woody debris in rockfall simulations based on a higher compaction rate and lower energy absorption thresholds. Simulations including different deadwood states indicate that a ten-year-old deadwood pile has a higher protective capacity than a pre-storm forest stand.

Grain size data are important for studying and managing rivers, but they are difficult to obtain in the field. Therefore, methods have been developed that use images from small and remotely piloted aircrafts. However, uncertainty in grain size data from such image-based products is poorly studied. Here we present a new way of uncertainty estimation that includes fully propagated errors. We use this technique to assess the effect of several image acquisition aspects on grain size uncertainty.

It is of great importance to engineers and geomorphologists to predict the rate of bedload in rivers. In this contribution, we used a large dataset of measured data and developed an artificial neural network (ANN), a machine learning algorithm, for bedload prediction. The ANN model predicted the bedload flux close to measured values and better than the ones obtained from four standard bedload models with varying degrees of complexity.

The geomorphic activity of LIA-lateral moraines is of high interest due to its implications for the sediment fluxes and hazards within proglacial areas. We derived multitemporal DEMs from historical aerial images and recent drone images to investigate the morphodynamics on moraine slopes over time. We found that the highest erosion rates occur on the steepest moraine slopes, which stay active for decades, and that the slope angle explains morphodynamics better than the time since deglaciation.

The supply of sediment (sand and gravel) carried by a stream out of a steep mountain valley is widely thought to control the gradient of the fan-shaped landforms that streams often build where they leave their valley. We tested this idea in a set of "sandbox" experiments with oscillating high and low sediment supply. Even though the average sediment supply never changed, longer oscillations built flatter fans, indicating how wetter climates might affect these mountain landforms.

Biological activity in shallow tidal environments significant influence the sediment dynamic and morphology. Here, a bio-morphodynamic model that accounts for hydro-climate variations on biofilm development to estimate the effect of biostabilisation on the bed is developed. Results reveal that key parameters such as growth rate and temperature strongly influence the development of biofilm under a range of disturbance periodicities and intensities, shaping the channel equilibrium profile.

A template that helps in the classification of gravitational mass movements (snow avalanches, lahars and debris flows) by simply overlaying it graphically with the corresponding spectrogram of the generated seismic signals is presented. The events must approach the seismic sensor. The template is created taking into account the propagation properties of seismic waves generated by the events. Examples are presented.

Predicting the extent and thickness of debris flow deposits is important for assessing and mitigating hazards. We propose a simplified mass balance model for predicting the morphology of a terminated debris flow depositing over complex topography. A key element in this model is that the termination of flow of the deposit is determined by prescribed values of yield stress and friction angle. The model results are consistent with available analytical solutions, field and laboratory observations.

Channel processes under flood conditions are important for river science and management as they involve high volumes of sediment transport and erosion. However, these processes remain poorly understood as the data is difficult to collect. Using a physical model of a river, we found that simple equations based on the mean shear stress and median grain size predicted sediment transport as accurately as ones that accounted for the full range of shear stresses.

The morphology and size of sediments inform on their transport history, are important factors controlling the efficiency of erosion and transport, and control the quality of aquatic ecosystems. Here, we have developed a new software which aims at automatically identifying and measuring grains based on 3D topographic data of the surface of sediment deposits. This software is fast and efficient and offers a new avenue to measure the geometrical properties of large numbers of grains.

Microseismic events recorded on the Åknes rocklospe in Norway during the past 15 years are automatically classified into eight classes. Results are analysed and compared to meteorological data, showing a strong increase of the microseismic activity in spring mainly due to freezing and thawing processes.