Preprints
Filtering by Subject: Geology
Facies and Architectural Asymmetry in a Conglomerate-Rich Submarine Channel Fill, Cerro Toro Formation, Sierra Del Toro, Magallanes Basin, Chile
Published: 2018-01-25
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Cross-sectional asymmetry is characteristic of sinuous channels, in both fluvial and submarine settings. Less well documented are the facies distributions of asymmetric channels, particularly in submarine settings. Exposures of the axial channel-belt in the Magallanes retro-arc foreland basin on Sierra del Toro represent the fill of a 3.5 km wide, 300 m thick channel complex, here termed the [...]
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 [...]
Relict topography within the Hangay Mountains in central Mongolia: Quantifying long-term exhumation and relief change in an old landscape
Published: 2018-01-15
Subjects: Earth Sciences, Geochemistry, Geology, Geomorphology, Physical Sciences and Mathematics, Tectonics and Structure
The Hangay Mountains are a high-elevation, low-relief landscape within the greater Mongolian Plateau of central Asia. New bedrock apatite (U-Th)/He single-grain ages from the Hangay span ~70 to 200 Ma, with a mean of 122.7 ± 24.0 Ma (2σ). Detrital apatite samples from the Selenga and Orkhon Rivers, north of the mountains, yield dominant (U-Th)/He age populations of ~115 to 130 Ma, as well as an [...]
Cenozoic tectonics of the Tuz Gölü Basin (Central Anatolian Plateau, Turkey)
Published: 2018-01-14
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
We present a new 3D geologic model for the architecture and Cenozoic tectonic evolution of the Tuz Gölü Basin, a major sedimentary basin in the Central Anatolian orogenic plateau. This model is grounded on 7 depth-converted seismic reflection profiles in combination with the analysis of backstripped subsidence curves, isochore maps, and a palinspastically restored cross-section. Two stages of [...]
Climate-driven unsteady denudation and sediment flux in a high-relief unglaciated catchment-fan using 26Al and 10Be: Panamint Valley, California
Published: 2018-01-14
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, [...]
Linked Geoscience Data in practice: Where W3C standards meet domain knowledge, data visualization and OGC standards
Published: 2018-01-11
Subjects: Computer Sciences, Earth Sciences, Geology, Physical Sciences and Mathematics
The geoscience community is now facing both the challenge and the opportunity caused by the vast amount of datasets that can be made available on the Web. An efficient “data environment” on the Web has the potential to enable geoscientists to conduct their research in ways that never existed before. Standards developed by the Open Geospatial Consortium have already been used widely to build data [...]
Microstructural controls on the pressure-dependent permeability of Whitby Mudstone
Published: 2018-01-09
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
A combination of permeability and ultrasonic velocity measurements allied with image analysis is used to distinguish the primary microstructural controls on effective-pressure dependent permeability. Permeabilities of cylindrical samples of Whitby Mudstone were measured using the oscillating pore pressure method at confining pressures ranging between 30-95 MPa and pore pressures ranging between [...]
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 [...]
Geometry and Kinematics of Salt-detached Ramp Syncline Basins
Published: 2017-12-24
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Stratigraphy, Tectonics and Structure
Ramp-syncline basins (RSBs) are characterized by asymmetric depocentres that form by translation above flat-ramp extensional faults or salt detachments having basal steps. Both types of RSBs are composed by landward-dipping and expanding strata defined by basinward-dipping axial traces. 3D seismic data from the São Paulo Plateau, Santos Basin, Brazil, image a series of RSBs formed above thick [...]
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 [...]
Structural signatures of igneous sheet intrusion propagation
Published: 2017-12-08
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
The geometry and distribution of planar igneous bodies (i.e. sheet intrusions), such as dykes, sills, and inclined sheets, has long been used to determine emplacement mechanics, define melt source locations, and reconstruct palaeostress conditions to shed light on various tectonic and magmatic processes. Since the 1970’s we have recognised that sheet intrusions do not necessarily display a [...]
Subsurface expression of a tertiary salt weld, Gulf of Mexico
Published: 2017-12-06
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Salt welds form due to salt expulsion and thinning by mechanical (e.g. salt flow) and/or chemical (e.g. salt dissolution) processes. Despite being ubiquitous in salt-bearing sedimentary basins, where they may trap large volumes of hydrocarbons, little is published on weld thickness and composition. We here use 3D seismic reflection, borehole, and biostratigraphic data from the Atwater Valley [...]
Kinematics of Polygonal Fault Systems: Observations from the Northern North Sea
Published: 2017-12-05
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Layer-bound, low-displacement normal faults, arranged into a broadly polygonal pattern, are common in many sedimentary basins. Despite having constrained their gross geometry, we have a relatively poor understanding of the processes controlling the nucleation and growth (i.e., the kinematics) of polygonal fault systems. In this study we use high-resolution 3-D seismic reflection and borehole data [...]