Preprints
Filtering by Subject: Geology
Synchronizing terrestrial and marine records of environmental change across the Eocene–Oligocene transition
Published: 2017-11-05
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Stratigraphy
Synchronizing terrestrial and marine records of environmental change across the Eocene–Oligocene transition
Geological applications of digital terrain analysis
Published: 2017-11-01
Subjects: Earth Sciences, Geochemistry, Geographic Information Sciences, Geography, Geology, Geomorphology, Geophysics and Seismology, Physical Sciences and Mathematics, Remote Sensing, Social and Behavioral Sciences, Spatial Science, Tectonics and Structure, Volcanology
Editorial to the IJGIS Special Issue on "Geological applications of digital terrain analysis". In this volume, the modern advances in the field of geological terrain analysis are presented, while emphasis is given to the quantitative analysis of modern datasets.
Reactivation of intrabasement structures during rifting - A case study from offshore southern Norway
Published: 2017-11-01
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Pre-existing structures within crystalline basement may exert a significant influence over the evolution of rifts. However, the exact manner in which these structures reactivate and thus their degree of influence over the overlying rift is poorly understood. Using borehole-constrained 2D and 3D seismic reflection data from offshore southern Norway we identify and constrain the three-dimensional [...]
A general model for the helical structure of geophysical flows in channel bends
Published: 2017-10-31
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Engineering, Environmental Sciences, Fluid Dynamics, Geology, Geomorphology, Geophysics and Seismology, Hydrology, Life Sciences, Natural Resources and Conservation, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Oil, Gas, and Energy, Other Physical Sciences and Mathematics, Physical Sciences and Mathematics, Physics, Risk Analysis, Sedimentology
Meandering channels host geophysical flows that form the most extensive sediment transport systems on Earth (i.e. rivers and submarine channels). Measurements of helical flow structures in bends have been key to understanding sediment transport in rivers. Turbidity currents differ from rivers in both density and velocity profiles. These differences, and the lack of field measurements of turbidity [...]
Nature, origin and evolution of a Late Pleistocene incised valley-fill, Sunda Shelf, Southeast Asia
Published: 2017-10-31
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Understanding the stratigraphic fill and reconstructing the palaeo-hydrology of incised valleys can help to constrain those factors that controlled their origin, evolution and regional significance. This condition is addressed through the analysis of a large (up to 18 km wide by 80 m deep) and exceptionally well-imaged Late Pleistocene incised valley from the Sunda Shelf (South China Sea) based [...]
Development of cutoff-related knickpoints during early evolution of submarine channels
Published: 2017-10-30
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics
Submarine channels are often thought of as having relatively simple geometries, with significant along-channel morphologic and stratigraphic continuity. Using high-resolution seismic reflection data from offshore Angola and a kinematic model of channel evolution, we present evidence that channels on the seafloor can develop slope variability as a result of meander cutoff events. When cutoffs [...]
Seismic Interpretation of Sill-Complexes in Sedimentary Basins: The ‘Sub-Sill Imaging Problem’
Published: 2017-10-30
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Volcanology
Application of 3D-seismic reflection-data to igneous systems in sedimentary basins has led to a revolution in the understanding of mafic sill-complexes. However, there is considerable uncertainty on how geometries and architecture of sill complexes within the subsurface relates those imaged in seismic reflection-data. To provide constraints on how sill complexes in seismic data should be [...]
Influence of fault reactivation during multiphase rifting: the Oseberg area, Northern North Sea rift
Published: 2017-10-28
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Multiphase rifts tend to produce fault populations that evolve by the formation of new faults and reactivation of earlier faults. The resulting fault patterns tend to be complex and difficult to decipher. In this work we use seismic reflection data to examine the evolution of a normal fault network in the Oseberg Fault Block in the northern North Sea Rift System – a rift system that experienced [...]
Pre-existing normal faults have limited control on the rift geometry of the northern North Sea
Published: 2017-10-28
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Many rifts develop in response to multiphase extension with numerical and physical models suggesting that reactivation of first-phase normal faults and rift-related variations in bulk crustal rheology control the evolution and final geometry of subsequent rifts. However, many natural multiphase rifts are deeply buried and thus poorly exposed in the field and poorly imaged in seismic reflection [...]
Balancing sub- and supra-salt strain in salt-influenced rifts: Implications for extension estimates
Published: 2017-10-28
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
The structural style of salt-influenced rifts may differ from those formed in predominantly brittle crust. Salt can decouple sub- and supra-salt strain, causing sub-salt faults to be geometrically decoupled from, but kinematically coupled to and responsible for, supra-salt forced folding. Salt-influenced rifts thus contain more folds than their brittle counterparts, an observation often ignored [...]
Preconditioning and triggering of offshore slope failures and turbidity currents revealed by most detailed monitoring yet at a fjord-head delta
Published: 2017-10-26
Subjects: Earth Sciences, Geology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Sedimentology
Rivers and turbidity currents are the two most important sediment transport processes by volume on Earth. Various hypotheses have been proposed for triggering of turbidity currents offshore from river mouths, including direct plunging of river discharge, delta mouth bar flushing or slope failure caused by low tides and gas expansion, earthquakes and rapid sedimentation. During 2011, 106 turbidity [...]
Thermo-mechanical numerical model of the transition from continental rifting to oceanic spreading: the case study of the Alpine Tethys
Published: 2017-10-26
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
We develop a two-dimensional thermo-mechanical numerical model in which the formation of oceanic crust and serpentinite due to the hydration of the uprising mantle peridotite has been implemented, with the aim of discussing the behavior of the lithosphere of the Alps and Northern Apennines during the transition from continental rifting to ocean spreading of the Alpine Tethys. The predictions of [...]
Morphological expressions of crater infill collapse: model simulations of Chaotic Terrains on Mars
Published: 2017-10-26
Subjects: Earth Sciences, Geology, Geomorphology, Other Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Martian chaotic terrains are characterized by deeply depressed intensively fractured areas that contain a large number of low-strain tilted blocks. Stronger deformation (e.g. higher number of fractures) is generally observed in the rims when compared to the middle regions of the terrains. The distribution and number of fractures and tilted blocks are correlated with the size of the chaotic [...]
2-D numerical study of hydrated wedge dynamics from subduction to post-collisional phases
Published: 2017-10-26
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
We developed a 2-D finite element model to investigate the effect of shear heating and mantle hydration on the dynamics of the mantle wedge area. The model considers an initial phase of active oceanic subduction, which is followed by a post-collisional phase characterized by pure gravitational evolution. To investigate the impact of the subduction velocity on the thermomechanics of the system, [...]
Direct monitoring of active geohazards: emerging geophysical tools for deep-water assessments
Published: 2017-10-26
Subjects: Earth Sciences, Geology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Sedimentology
Seafloor networks of cables, pipelines, and other infrastructure underpin our daily lives, providing communication links, information, and energy supplies. Despite their global importance, these networks are vulnerable to damage by a number of natural seafloor hazards, including landslides, turbidity currents, fluid flow, and scour. Conventional geophysical techniques, such as high-resolution [...]