Quantitative analysis of digital topography is an important part of many modern geologic investigations. We have constructed a series of open source tools, the Topographic Analysis Kit (TAK), built on top of the existing TopoToolbox library, to allow for efficient and easy analysis of topography that limits the required computing and domain specific knowledge necessary to successfully produce robust analyses of topographic data.

This research article provides a comparison between the traditional method of measuring erosion on rock shore platforms using a Traversing/Micro Erosion Meter (T/MEM) and a new approach using Structure from Motion (SfM) Photogrammetry. Our results indicate that SfM Photogrammetry offers several advantages over the T/MEM allowing measurement of erosion at different scales on rock surfaces with low roughness while also providing a means for identifying different processes and styles of erosion.

This work demonstrates how seismic networks installed in the Alps can be used for country-wide real-time monitoring of rockslide activity. We suggest several simple methods which allow to detect, locate and characterize rockslides using the seismic signals they generate. We developed an automatic procedure that allows to locate rockslides with kilometer accuracy over hundreds of kilometers distance. Our findings highlight how seismic networks can help to understand the triggering of rockslides.

The uppermost part of the permafrost thaws during summer and freezes again during winter. We use a passive seismic method to monitor these changes continuously between April and August 2016 close to Ny Ålesund, Svalbard. Our results reveal some potential pitfalls when interpreting temporal variations. However, we show that after a careful analysis this method has the potential to become a very useful tool for long-term permafrost monitoring, being of special importance in a changing climate.

We show a new and novel use for the SRTM-C digital elevation model from February 2000 and the newer TanDEM-X dataset from ~ 2015. We difference the datasets over hillslopes and gravel-bed channels to extract vertical land-level changes. These signals are associated with incision, aggradation, and landsliding. This requires careful correction of the SRTM-C biases using the TanDEM-X, with the possibility to extend the method to moderate relief areas with SRTM-C and TanDEM-X coverage.

Landscape evolution models (LEMs) aim to capture an aggregation of the processes of erosion and deposition, and predict evolving topography. A key aspect of any LEM is how water is chosen to be routed down the surface, which can impact the model results and importantly the numerical accuracy. I find that by treating rivers as lines within the model domain, and by distributing water down all slopes, the results are independent of resolution, pointing to a new method to model landscape evolution.

Deltas are important landforms because many people live near them, and they provide a host of important services and resources.Specific patterns of spreading and contraction are produced where delta channel flow meets the ocean. Tracers on the water surface allow this pattern to be measured from space. We identify this pattern on a growing river delta in 40 years of images, allowing us to track its growth in a new way. This method has potential to improve monitoring of deltas worldwide.

Barrier islands change through time and space in response to natural and human forces. This paper demonstrates that barrier island development and the beach-dune system can be influenced asymmetrically during island development by ancient and buried river valleys that cross the modern barrier island. Given the importance of the natural environment, coastal management projects should first seek to understand how the island developed in order to more effectively balance natural and human pressure.

This paper presents applications of Structure-from-Motion Photogrammetry in a physical model of a braided river used to quantify morphology change and provide estimates of water depth, as well as image analysis for mapping bed surface texture.

The grain-size distribution of ancient alluvial systems is commonly determined from sections of gravel deposits exposed vertically to reconstruct paleo-environments or changes in tectonic and/or climate. To test whether such grain-size distribution is equivalent to the one of the sediments that were in direct contact with the flow at the time of deposition, we dug a large trench in an active gravel-bed braided river. We show that the granulometry is uniform at the scale of the active layer.

In most models of river morphodynamics, sediment mass conservation is described by the Exner equation, which may take either the flux form or the entrainment form. Here we compare the two forms of Exner equation under conditions typical of the Lower Yellow River. We find that when using a single sediment grain size, there is little difference between the two forms. But when considering sediment mixtures, the two forms will show very different patterns of grain sorting.

Erosion by glaciers can limit the height to which mountains grow. The prevalence of this phenomenon is debated, and it is thought that glaciers only limit mountain height in temperate regions, where glaciers grow large during cold periods. We present evidence that glacial erosion has limited the rise of mountains in tropical Costa Rica and Taiwan, where glaciers are only intermittently present. Our work points to the remarkable efficiency of glacial erosion, even in the warmest places.

Rivers can raise or lower their beds by depositing or eroding sediments. We combined equations for flow, channel geometry, and gravel transport, to learn how changes in climate and tectonics shape profiles of river-bed elevation downstream. Rivers steepen when they receive more sediment (relative to water) and become straighter with tectonic uplift. Weathering and valley widening are required to produce gradually widening rivers with concave-up profiles that are often observed in the field.

This paper examines how an experimental mega-scale beach nourishment (Sand Motor) contributes to creating favorable conditions for dune development. These conditions, involving a steady supply of wind-blown sand towards space where it can accumulate, are identified using publicly available remote sensing data. It is demonstrated that the Sand Motor supports a high potential for new dunes to develop, but human disturbances may hamper this development which negatively impacts coastal safety.

Glaciations may induce significant changes in the catchments of major sedimentary systems over time, also during a single glaciation. The rugged morphology of Alpine valleys may slow, block or divert glacial tongues. Such conclusion arises from the reconstruction we made of the Brenta (NE Italy) glacial system dynamics through sediment analysis techniques on its alluvial stratigraphic record and the mapping of in-valley glacial/glaciofluvial remnants.

We used a numerical model to study how mountain streams adjust to series of sediment input events, e.g. landslides. We first recreated laboratory stream experiments with similar scope and then expanded their parameter space, allowing us to find when the stream becomes overloaded with sediment. This occurs when the stream cannot evacuate a sediment input in the time between pulses. Our results can help to better understand the long term adjustment of mountain streams to episodic sediment supply.

In this work we combined the results of the automatic classification of continuous seismic data recorded at two arrays to identify avalanches. By using an additional post-processing step based on the localization of avalanches, we were able to identify 27 avalanches during the winter period 2016–2017. Comparing these results with visually identified avalanches, we were able to reconstruct the main avalanche periods of the winter season.

Clast imbrications, which is a depositional fabric where clasts overlap each other similar to a run of toppled dominoes, are presumably the most conspicuous sedimentary structures in coarse-grained fluvial deposits. However, the conditions leading to this fabric has been contested. Here, we calculate the hydrological conditions for various stream gradients. We find that clast imbrications most likely form where channel gradients exceed a threshold and where upper flow regime conditions prevail.

Identifying contemporary river migration rates is often based on aerial photos or recent topographical maps. Here, we propose to use river sediments as an archive to look further back in time using optically stimulated luminescence (OSL) dating, and develop a modelling procedure for the joint analysis of dating results and historical maps. The procedure is applied to the Overijsselse Vecht river in The Netherlands, and we show that the river migrated with 0.9–2.6 m/y between 1400–1900 AD.