Preprints
Filtering by Subject: Geomorphology
Centennial- and orbital-scale erosion beneath the Greenland Ice Sheet
Published: 2021-08-31
Subjects: Earth Sciences, Geochemistry, Geomorphology, Glaciology
Erosion beneath glaciers and ice sheets is a fundamental Earth-surface process dictating landscape development, which in turn influences ice-flow dynamics and the climate sensitivity of ice masses. The rate at which subglacial erosion takes place, however, is notoriously difficult to observe because it occurs beneath modern glaciers in a largely inaccessible environment. Here, we present 1) [...]
Safety and Belonging in the Field: A Checklist for Educators
Published: 2021-08-19
Subjects: Atmospheric Sciences, Biogeochemistry, Climate, Cosmochemistry, Earth Sciences, Education, Environmental Education, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Environmental Studies, Fresh Water Studies, Geochemistry, Geographic Information Sciences, Geography, Geology, Geomorphology, Geophysics and Seismology, Glaciology, Higher Education, Human Geography, Hydrology, Life Sciences, Meteorology, Mineral Physics, Natural Resource Economics, Natural Resources and Conservation, Natural Resources Management and Policy, Nature and Society Relations, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Oil, Gas, and Energy, Other Earth Sciences, Other Environmental Sciences, Other Geography, Other Oceanography and Atmospheric Sciences and Meteorology, Other Planetary Sciences, Outdoor Education, Paleobiology, Paleontology, Physical and Environmental Geography, Physical Sciences and Mathematics, Planetary Biogeochemistry, Planetary Geochemistry, Planetary Geology, Planetary Geomorphology, Planetary Geophysics and Seismology, Planetary Glaciology, Planetary Hydrology, Planetary Mineral Physics, Planetary Sciences, Planetary Sedimentology, Remote Sensing, Sedimentology, Social and Behavioral Sciences, Soil Science, Spatial Science, Speleology, Stratigraphy, Sustainability, Tectonics and Structure, Volcanology, Water Resource Management
Ensuring taught fieldwork is a positive, generative, collective, and valuable experience for all participants requires considerations beyond course content. To guarantee safety and belonging, participants’ identities (backgrounds and protected characteristics) must be considered as a part of fieldwork planning and implementation. Furthermore, getting fieldwork right is an important step in [...]
Calibration, inversion and sensitivity analysis for hydro-morphodynamic models
Published: 2021-08-03
Subjects: Applied Mathematics, Fluid Dynamics, Geomorphology, Numerical Analysis and Computation, Partial Differential Equations, Programming Languages and Compilers
The development of reliable, sophisticated hydro-morphodynamic models is essential for protecting the coastal environment against hazards such as flooding and erosion. There exists a high degree of uncertainty associated with the application of these models, in part due to incomplete knowledge of various physical, empirical and numerical closure related parameters in both the hydrodynamic and [...]
The world’s second-largest, recorded landslide event: lessons learnt from the landslides triggered during and after the 2018 Mw 7.5 Papua New Guinea earthquake
Published: 2021-07-30
Subjects: Geology, Geomorphology, Geophysics and Seismology, Hydrology, Other Earth Sciences
Widespread landslide events provide rare but valuable opportunities to investigate the spatial and size distributions of landslides in relation to seismic, climatic, geological and morphological factors. This study presents a unique event inventory for the co-seismic landslides induced by the February 25, 2018 Mw 7.5 Papua New Guinea earthquake as well as its post-seismic counterparts including [...]
Contrasting geomorphic and stratigraphic responses to normal fault development during single and multi-phase rifting
Published: 2021-07-27
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics, Tectonics and Structure
Understanding the impact of tectonics on surface processes and the resultant stratigraphic evolution in multi-phase rifts is challenging, as patterns of erosion and deposition related to older phases of extension are overprinted by the subsequent extensional phases. In this study, we use a one-way coupled numerical modelling approach between a tectonic and a surface processes model to investigate [...]
Floods on alluvial fans: implications for reworking rates, morphology and fan hazards
Published: 2021-07-26
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Flood events are the agents of change on alluvial fans. However, most alluvial fan experiments have used constant flows to model fans and the channels upon them. Here, we present results from a series of alluvial fan experiments with different patterns of flow variation (i.e. different hydrograph shapes). We conducted experiments with 1) constant flow, 2) alternating high and low flows, 3) a [...]
When does faulting-induced subsidence drive distributary network reorganization?
Published: 2021-07-18
Subjects: Earth Sciences, Geomorphology
Deltas exhibit spatially and temporally variable subsidence, including vertical displacement due to movement along fault planes. Faulting-induced subsidence perturbs delta-surface gradients, potentially causing distributary networks to shift sediment dispersal within the landscape. Sediment dispersal restricted to part of the landscape could hinder billion-dollar investments aiming to restore [...]
Sandstone body character, river styles, and geomorphology of the lower Eocene Willwood Formation, Bighorn Basin, Wyoming, USA
Published: 2021-07-18
Subjects: Geology, Geomorphology, Sedimentology
The lower Eocene Willwood Formation of the Bighorn Basin, Wyoming, USA, is an alluvial succession with a sand content varying around 25%. It has been studied intensively for palaeontology, palaeoenvironments and palaeoclimates, as well as sedimentological and stratigraphic analysis. Channel dynamics were studied at a relatively low resolution throughout the basin over the geological time from [...]
Created by the Monte Peron rock avalanche: Lago di Vedana (Dolomites, Italy) and its sediment record of landscape evolution after a mass wasting event
Published: 2021-07-09
Subjects: Earth Sciences, Geochemistry, Geology, Geomorphology
The timing of the Monte Peron Landslide is revised to 2890 cal. BP based on a radiocarbon-dated sediment stratigraphy of Lago di Vedana. This age fosters the importance of hydroclimatic triggers in the light of accelerating global warming with a predicted increase of precipitation enhancing the regional predisposition to large landslides. Moreover, a layer enriched in allochthonous organic and [...]
Cosmogenic 3He in terrestrial rocks: a review
Published: 2021-07-05
Subjects: Earth Sciences, Geochemistry, Geology, Geomorphology, Glaciology, Other Earth Sciences
This review article summarizes the state of the art of cosmogenic 3He (3Hec), with a focus on the most efficient methods and strategies for measuring this cosmogenic noble gas in the terrestrial minerals. Our ability to accurately and precisely measure cosmogenic 3He in minerals is mainly constrained by the level of the non-cosmogenic 3He background (i.e., magmatic, radiogenic, nucleogenic, and [...]
Onset of runaway fragmentation of salt marshes
Published: 2021-06-30
Subjects: Earth Sciences, Geomorphology, Hydrology, Sustainability
Salt marshes are valuable but vulnerable coastal ecosystems that adapt to relative sea level rise (RSLR) by accumulating organic matter and inorganic sediment. The natural limit of these processes defines a threshold rate of RSLR beyond which marshes drown, resulting in ponding and conversion to open waters. We develop a simplified formulation for sediment transport across marshes to show that [...]
Controls on submarine canyon connection to the shoreline: a numerical modelling approach
Published: 2021-06-29
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics
Submarine canyons with heads located close to shorelines, known as shore-connected canyons, provide a focussed pathway for basinward sediment transport. Placing greater constraints on the key parameters that control the formation of shore-connected canyons can help us predict the efficiency of sediment export to deep-water under different environmental conditions and through time. Using a [...]
Late Quaternary climatic histories from the Hermes Cave, Corinth Rift, Greece
Published: 2021-06-25
Subjects: Earth Sciences, Geochemistry, Geomorphology, Sedimentology, Speleology
The Greek peninsula is located at the crossroads of several major atmospheric circulation patterns and is consequently characterized by high variability in climatic conditions, making it an important location to examine past climate variability. Over the last decades, the focus of many studies in the region has been to unravel Holocene paleoclimatic oscillations and their impact on the [...]
Rift kinematics preserved in deep-time erosional landscape below the northern North Sea
Published: 2021-06-25
Subjects: Earth Sciences, Geology, Geomorphology, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Our understanding of continental rifting is, in large parts, derived from the stratigraphic record. This record is, however, incomplete as it does not often capture the geomorphic and erosional signal of rifting. New 3D seismic reflection data reveals a Late Permian-Early Triassic landscape incised into the pre-rift basement of the northern North Sea. This landscape, which covers at least 542 [...]
Environmental variability at the margin of the South American Monsoon System recorded by a high-resolution sediment record from Lagoa Dourada (South Brazil)
Published: 2021-06-25
Subjects: Earth Sciences, Geochemistry, Geomorphology, Sedimentology
High-resolution geochemical and sedimentological data have been obtained for a lacustrine sediment record from Lagoa Dourada (South Brazil). Four distinctly different depositional processes were determined: (1) Suspension fallout of fine-grained minerogenic particles transferred via fluvial activity dominates the Early Holocene and relates to open grassland in the catchment area; (2) Activation [...]