Preprints
Filtering by Subject: Sedimentology
Salt thickness and composition influence rift structural style, northern North Sea, offshore Norway
Published: 2018-01-24
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Tectonics and Structure
‘Salt’ giants are typically halite-dominated, although they invariably contain other evaporite (e.g. anhydrite, bittern salts) and non-evaporite (e.g. carbonate, clastic) rocks. Rheological differences between these rocks mean they impact or respond to rift-related, upper crustal deformation in different ways. Our understanding of basin-scale lithology variations in ancient salt giants, what [...]
Depositional processes, bedform development and hybrid bed formation in rapidly decelerated cohesive (mud–sand) sediment flows
Published: 2018-01-16
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
Flows with high suspended sediment concentrations are common in many sedimentary environments, and their flow properties may show a transitional behaviour between fully turbulent and quasi-laminar plug flows. The characteristics of these transitional flows are known to be a function of both clay concentration and type as well as the applied fluid stress, but so far the interaction of these [...]
A phase diagram for turbulent, transitional and laminar clay suspension flows
Published: 2018-01-16
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
New phase diagrams for the dynamic structure of clay-laden open-channel flows are proposed. These diagrams can be used to distinguish between turbulent Newtonian, transitional, and laminar non-Newtonian flow behavior, on the basis of the balance between turbulent forces (approximated by the horizontal components of flow velocity and turbulence intensity) and cohesive forces (approximated by the [...]
Climate-driven unsteady denudation and sediment flux in a high-relief unglaciated catchment-fan using 26Al and 10Be: Panamint Valley, California
Published: 2018-01-13
Subjects: Earth Sciences, Geochemistry, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology
Environmental changes within erosional catchments of sediment routing systems are predicted to modulate sediment transfer dynamics. However, empirical and numerical models that predict such phenomena are difficult to test in natural systems over multi-millennial timescales. Tectonic boundary conditions and climate history in the Panamint Range, California, are relatively well-constrained by [...]
A consistent global approach for morphometric characterisation of subaqueous landslides
Published: 2018-01-12
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Life Sciences, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Landslides are common in aquatic settings worldwide, from lakes and coastal environments to the deep-sea. Fast-moving, large volume landslides can potentially trigger destructive tsunamis. Landslides damage and disrupt global communication links and other critical marine infrastructure. Landslide deposits act as foci for localised, but important deep-seafloor biological communities. Under burial, [...]
Frontal and lateral submarine lobe fringes: Comparing sedimentary facies, architecture and flow processes
Published: 2018-01-08
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
Submarine lobe fringe deposits form heterolithic successions that may include a high proportion of hybrid beds. The identification of lobe fringe successions aids interpretation of paleogeographic setting and the degree of basin confinement. Here, for the first time, the sedimentological and architectural differences between frontal and lateral lobe fringe deposits are investigated. Extensive [...]
Estimating regional flood discharge during Palaeocene-Eocene global warming (submitted)
Published: 2018-01-04
Subjects: Climate, Earth Sciences, Environmental Sciences, Geology, Geomorphology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Among the most urgent challenges in future climate change scenarios is accurately predicting the magnitude at which precipitation extremes will intensify. Analogous changes have been reported for an episode of millennial scale 5°C warming termed the Palaeocene-Eocene Thermal Maximum (PETM; 56 Ma), providing independent constraints on hydrological response to global warming. However, quantifying [...]
Exogenic forcing and autogenic processes on continental divide location and mobility -- preprint
Published: 2017-12-22
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics, Sedimentology
The position and mobility of drainage divides is an expression of exogenic landscape forcing and autogenic channel network processes integrated across a range of scales. At the large scale, represented by major rivers and continental drainage divides, the organization of drainage patterns and divide migration reflects the long-wavelength gradients of the topography, which are exogenically [...]
Slope-fan depositional architecture from high-resolution forward stratigraphic models
Published: 2017-12-19
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Submarine fans in tectonically active continental-slope basins are targets of petroleum exploration and production. These slope fans commonly comprise compensationally stacked sandy and muddy architectural elements, including mass-transport deposits, weakly confined to distributary channel-and-lobe deposits, and leveed-channel deposits. The lateral continuity and vertical connectivity of these [...]
Stratigraphic modeling of the Western Taiwan foreland basin: sediment flux from a growing mountain range and tectonic implications
Published: 2017-12-11
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Sediment flux signals in foreland basins preserve a record of tectonics, sea level and climate through erosion and sedimentation. However, longitudinal sediment transport often occurs in foreland basin, thus removing part of the orogenic material flux from foreland basins. Here we use mass balance calculation and stratigraphic simulations of sediment fluxes for the Taiwan orogen to provide a [...]
Inverse analysis to reconstruct hydraulic conditions of non-steady turbidity currents based on multiple grain-size classes
Published: 2017-12-06
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
This study proposes a new method of inverse analysis of ancient turbidites to represent non-steady turbidity currents and account for multiple grain-size classes. The forward model employed in this study is based on the shallow water equation, and the initial conditions of flows are assumed as a lock-exchange type. To obtain a solution to the inverse problem, a genetic algorithm is employed to [...]
Types of mixing and heterogeneities in siliciclastic-carbonate sediments
Published: 2017-12-05
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
Mixed siliciclastic-carbonate deposits consist of a suite of different types of mixing between the two components, from bed (core-plug) to stratigraphic (seismic) scales, producing a high vertical and lateral lithological variability. Mixed deposits result from the interaction of siliciclastic input and coeval carbonate production controlled by temporal and/or spatial factors. Although mixed [...]
Sedimentology and reservoir properties of tabular and erosive offshore transition deposits in wave-dominated, shallow-marine strata: Book Cliffs, USA
Published: 2017-11-28
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology
Facies models for wave-dominated shorelines include an "offshore transition zone" between shelfal mudstones and nearshore shoreface sandstones. Offshore transition zone deposits are commonly tabular sandstone beds interbedded with continuous mudstone beds. However, observations from the Blackhawk Formation show that the offshore transition zone locally consists of erosive-based sandstone beds [...]
BIOMEDIATION OF SEDIMENT GRAVITY FLOW DYNAMICS
Published: 2017-11-22
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
Sediment gravity flows (SGFs) are the primary process by which sediment and organic carbon are transported from the continental margin to the deep ocean. Forty percent of the total marine organic carbon pool is represented by cohesive extracellular polymeric substances (EPS) produced by marine benthic and pelagic micro-organisms. EPS research to date has focussed on coastal environments, where [...]
Different frequencies and triggers of canyon filling and flushing events in Nazaré Canyon, offshore Portugal
Published: 2017-11-09
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
Submarine canyons are one of the most important pathways for sediment transport into ocean basins. For this reason, understanding canyon architecture and sedimentary processes has importance for sediment budgets, carbon cycling, and geohazard assessment. Despite increasing knowledge of turbidity current triggers, the down-canyon variability in turbidity current frequency within most canyon [...]