Preprints
Filtering by Subject: Sedimentology
Macroplastic fragmentation in rivers
Published: 2023-05-25
Subjects: Earth Sciences, Environmental Indicators and Impact Assessment, Geomorphology, Hydrology, Other Earth Sciences, Other Environmental Sciences, Sedimentology
The process of macroplastic (>0.5 cm) fragmentation results in the production of smaller plastic particles (micro- and nanoplastics), which threaten biota and human health and are difficult to remove from the environment. The global coverage and long retention times of macroplastic waste in fluvial systems (ranging from years to centuries) create long-lasting and widespread potential for its [...]
Salt‑rich versus salt‑poor structural scenarios in the central Northern Calcareous Alps: implications for the Hallstatt facies and early Alpine tectonic evolution (Eastern Alps, Austria)
Published: 2023-05-25
Subjects: Other Earth Sciences, Sedimentology, Tectonics and Structure
One of the most remarkable features of the central Northern Calcareous Alps (Eastern Alps, Austria) is the widespread presence of Upper Triassic deep-water carbonates (the Hallstatt facies) and Permo-Triassic evaporites resting on deep-water Middle Jurassic strata and their underlying Upper Triassic shallow-water carbonate platform successions. The Hallstatt facies and accompanying evaporites [...]
In-situ frictional behavior of subducting sediment in the shallow Nankai Trough
Published: 2023-04-22
Subjects: Geology, Geophysics and Seismology, Sedimentology, Tectonics and Structure
The transition from smectite to illite at around the depth with temperature of ~150 °C has long been hypothesized as one of controlling factors of the updip limit depth of the seismogenic zone of subduction zones. Although illite has a higher friction coefficient than smectite, previous friction experiments have little reported that the smectite-illite transition accompanies the transition from [...]
Complex seabed geomorphology shaped by various oceanographic processes: a case study from the Gippsland Basin, offshore south-eastern Australia
Published: 2023-04-04
Subjects: Earth Sciences, Geology, Geomorphology, Sedimentology
The Gippsland Basin is located in the southeastern continental margin of Australia and hosts a variety of important marine resources. Recent high-resolution seabed mapping reveals that seabed morphology is extremely complex in different regions of the Gippsland Basin (i.e. northern, central and southern regions), ranging from scarps, cyclic step trains, channels, canyons, gullies, and giant [...]
Features of crevasse splay deposits and sedimentary processes associated with levee breaching by the October 2019 flood of the Chikuma River, Central Japan
Published: 2023-03-31
Subjects: Earth Sciences, Sedimentology
Field investigations and analyses of modern crevasse splay deposits can both elucidate the processes of levee breaching and help to identify past crevasse splay deposits from geologic strata, thereby estimating the magnitudes of ancient river floods. In this study, we studied levee breach processes and crevasse splay deposits in order to determine the distribution characteristics of the [...]
Stationary surface waves and antidunes in dense pyroclastic density currents
Published: 2023-03-28
Subjects: Earth Sciences, Sedimentology, Volcanology
Stationary antidunes are a product of critical flow in open channel systems, but with poor preservation potential. They are related to the existence of stationary surface waves in the overriding current, but their existence in the dense pyroclastic density current regime has been unrecognized to date. Experiments presented here demonstrate that surface waves in simulated dense pyroclastic density [...]
Structure and Morphology of an Active Conjugate Relay Zone, Messina Strait, Southern Italy
Published: 2023-03-10
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Tectonics and Structure
Messina Strait is a narrow fault-bounded marine basin that separates the Calabrian peninsula from Sicily in southern Italy. It sits in a seismically active region where normal fault scarps and raised Quaternary marine terraces record ongoing extension driven by southeastward rollback of the Calabrian subduction zone. A review of published studies and new data shows that normal faults in the [...]
Transformation of dense shelf water cascade into turbidity currents: insights from high-resolution geophysical datasets
Published: 2023-02-17
Subjects: Earth Sciences, Geomorphology, Sedimentology
Dense shelf water cascade (DSWC) is a common oceanographic phenomenon on many continental shelves. Previous studies indicate that the DSWC could shape seabed physiography and carry seawater, sediment, and organic carbon a long distance from the continental shelf to the basin floor. However, it remains enigmatic how these DSWC’s interact with seabed geomorphology and travel long distances from the [...]
Internal waves and bottom currents interactions around mesophotic reefs, southeastern Mediterranean
Published: 2023-01-24
Subjects: Environmental Monitoring, Geology, Marine Biology, Other Environmental Sciences, Sedimentology
Mesophotic reefs are found in water depths greater than 30m and as such are, for the most part, removed from most direct wave activity, notably in the Mediterranean Sea. There, they are protected from anthropogenic impact and serve as a possible refuge for marine biodiversity in a warming ocean. Yet, like any reef, their growth is modulated by the distribution of the sediment they produce and [...]
Improving Shoreline Forecasting Models with Multi-Objective Genetic Programming
Published: 2023-01-10
Subjects: Artificial Intelligence and Robotics, Climate, Environmental Engineering, Environmental Monitoring, Geomorphology, Hydrology, Numerical Analysis and Scientific Computing, Oceanography, Sedimentology, Statistical Models
Given the current context of climate change and increasing population densities at coastal zones, there is an increasing need to be able to predict the development of our coasts. Recent advances in artificial intelligence allow for automatic analysis of observational data. This work makes use of Symbolic Regression, a type of Machine Learning algorithm, to evolve interpretable shoreline [...]
Are marl-limestone alternations mainly driven by CaCO3 variations at the astronomical timescale? New insights from extraterrestrial 3He
Published: 2023-01-07
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy
Marl-limestone alternations are rhythmical inter-bedded deposits that commonly occur in many sedimentological environments. It is quite well established that these lithological variations originate from astronomically-driven climatic variations paced by the Milankovitch cycles of main periods 19, 23, 41, 100 and 405 ka. However, the sedimentological mechanisms involved are not clear: some models [...]
Application of micro-CT to deep-marine outcrop data: towards a new tool to better assess primary sedimentary structures and processes at their origin
Published: 2022-12-17
Subjects: Numerical Analysis and Scientific Computing, Sedimentology
A new application of micro-CT on consolidated sediment-gravity flow deposits is presented with the objectives to characterize its internal sedimentary three-dimensional (3D) structures. The proposed concept is applied to three types of deep-marine sandstones, sampled in study areas showing different compositional properties: the Upper Cretaceous Gosau Group (Austria), the Eocene Hecho Group [...]
Use of remote-sensing to quantify the distribution of progradation/erosion along a forced-regressive modern coastline: driving factors and impact on the stratigraphic record
Published: 2022-12-13
Subjects: Geomorphology, Sedimentology, Stratigraphy
The long-term development of ancient and modern coastal distributary distributive fluvial systems (DFSs) during periods of relative sea-level highstand or fall usually drives net-progradation of shorelines. Such systems often develop in periods of relative sea-level highstand or fall and typically record annual to millennial-scale deviations in coastal trajectories. A new continental dataset [...]
An interconnected palaeo-subglacial lake system in the central Barents Sea
Published: 2022-12-02
Subjects: Earth Sciences, Geology, Geomorphology, Glaciology, Sedimentology
Drainage of meltwater beneath an ice sheet influences ice-flow dynamics. To better predict ice sheet behaviour, it is crucial to understand subglacial hydrological processes. Subglacial lakes are important components of the subglacial hydrological system, with many observed and predicted at the beds of contemporary and palaeo-ice sheets. The technical and logistical challenges of studying [...]
The unknown fate of macroplastic in mountain rivers
Published: 2022-11-09
Subjects: Earth Sciences, Environmental Indicators and Impact Assessment, Environmental Monitoring, Geology, Geomorphology, Hydrology, Life Sciences, Natural Resources and Conservation, Sedimentology, Stratigraphy, Sustainability, Terrestrial and Aquatic Ecology, Water Resource Management
Mountain rivers are typically seen as relatively pristine ecosystems, supporting numerous goods (e.g., water resources) for human populations living not only in the mountain regions but also downstream from them. Recent evidence suggests, however, that mountain river valleys in populated areas can be substantially polluted by macroplastic (plastic item > 5 mm). It is, however, unknown how [...]