Preprints
Filtering by Subject: Tectonics and Structure
Brittle origin of off-fault fractures during the 2019 Ridgecrest earthquake sequence
Published: 2024-03-14
Subjects: Earth Sciences, Geophysics and Seismology, Tectonics and Structure
According to the classical Mohr-Coulomb-Anderson theory, faults form at an angle from the largest regional compressive stress that is approximately 30° for most rocks. However, real settings are more complex and faults often present orientations inconsistent with the angles predicted by the classical theory applied to the present-day regional stress field. The Ridgecrest region hosts a young [...]
The role of salt diapirism in controlling the sedimentology and distribution of deep-water deposits, Pierce Field, East Central Graben, North Sea
Published: 2024-03-04
Subjects: Earth Sciences, Geology, Other Earth Sciences, Sedimentology, Tectonics and Structure
Passively rising diapirs control flank deformation (i.e., within 1 km of the salt-sediment interface) and resultant stratigraphic architecture of syn-kinematic units. Growth strata associated with deformation at the flanks of passive diapirs are known as halokinetic sequences. Very few studies have conducted an integrated analysis of composite halokinetic sequences, CHS (stacked halokinetic [...]
Bayesian reconstruction of sea-level and hydroclimates from coastal landform inversion
Published: 2024-02-10
Subjects: Earth Sciences, Geology, Geomorphology, Tectonics and Structure
Quantifying Quaternary sea-level changes and hydroclimatic conditions is an important challenge given their intricate relation with paleo-climate, ice-sheets and geodynamics. The world’s coastlines provide an enormous geomorphologic archive, from which forward landscape evolution modelling studies have shown their potential to unravel paleo sea-levels, albeit at the cost of assumptions to [...]
Quaternary and Pliocene sea-level changes at Camarones, central Patagonia, Argentina
Published: 2024-01-20
Subjects: Earth Sciences, Geology, Geomorphology, Geophysics and Seismology, Tectonics and Structure
Geological indicators of past relative sea level changes are fundamental to reconstruct the extent of former ice sheet during past interglacials, which are considered analogs for future climate conditions. Four interglacials, dating from Holocene to Pliocene, have left sea-level imprints in the proximity of the coastal town of Camarones in Central Patagonia, Argentina. Sea-level index points were [...]
Transient aseismic vertical deformation across the Pisia-Skinos normal fault (Gulf of Corinth, Greece)
Published: 2024-01-18
Subjects: Earth Sciences, Geophysics and Seismology, Tectonics and Structure
Geodetically-derived deformation rates are sometimes used to infer seismic hazard, implicitly assuming that short-term (annual-decadal) deformation is representative of longer-term deformation. This is despite geological observations indicating that deformation/slip rates are variable over a range of timescales. Using geodetic data from 2016-2021, we observe an up to 7-fold increase in vertical [...]
Dynamic evolution of competing same-dip double subduction: New perspectives of the Neo-Tethyan plate tectonics
Published: 2024-01-15
Subjects: Earth Sciences, Geophysics and Seismology, Tectonics and Structure
Same-dip double-subduction (SDDS) systems are widely reported from present as well as past complex convergent plate tectonic configurations. However, the dynamics of their evolution is poorly understood, which is crucial to conceptualize anomalous subducting slab kinematics and associated observed geological phenomena, such as irregular trench migration rates, high convergence velocities, and [...]
Middle Jurassic to Early Cretaceous orogenesis in the Klamath Mountains Province (northern California-southern Oregon) occurred by tectonic switching: Insights from Detrital zircon U-Pb geochronology of the Condrey Mountain schist
Published: 2024-01-11
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
The Klamath Mountains province (KMP) of northern California and southern Oregon consists of generally east-dipping terranes assembled via Paleozoic to Mesozoic subduction along the western margin of North America. The KMP more than doubled in mass from Middle Jurassic to Early Cretaceous time, due to alternating episodes of extension (e.g, rifting and formation of the Josephine ophiolite) and [...]
Sensitivity Analysis of Global Kinematics on Mantle Structure Using Automatically Generated Adjoint Thermochemical Convection Codes
Published: 2023-12-11
Subjects: Earth Sciences, Geophysics and Seismology, Numerical Analysis and Scientific Computing, Tectonics and Structure
Within the past 30 years, numerical models of mantle convection have been able to predict observations on Earth and planets, and among them tectonics. The possibility of building inverse problems in global geodynamics became concrete, and often involve the development of adjoint codes. Such tools provide efficient ways to estimate sensitivities of misfit functions relative to control parameters, [...]
Petrological Evolution and Mass Redistribution in Basaltic Fault Zones: An Example from the Faroe Islands, North Atlantic Igneous Province
Published: 2023-11-06
Subjects: Earth Sciences, Geochemistry, Geology, Tectonics and Structure
Fault rock petrology exerts an important control on the permeability structure and mechanical properties of fault zones. Slip-related deformation on upper-crustal faults in basaltic rocks is closely associated with fluid-rock interaction, altering the distribution of physical properties within the fault. Here we present quantitative descriptions of the geochemical and petrological evolution of [...]
Quantifying fault interpretation uncertainties and their impact on fault seal and seismic hazard analysis
Published: 2023-10-31
Subjects: Geology, Tectonics and Structure
Fault-horizon cut-off data extracted from seismic reflection datasets are used to study normal fault geometry, displacement distribution, and growth history. We assess the influence of three seismic interpretation factors (repeatability, measurement obliquity, and fault cut-off type) on fault parameter uncertainty. Two repeat interpretations resulted in mean differences of 5-15% for throw, 11-42% [...]
Coral geochemical response to uplift in the aftermath of the 2005 Nias-Simeulue earthquake
Published: 2023-10-07
Subjects: Environmental Indicators and Impact Assessment, Geochemistry, Geomorphology, Natural Resources and Conservation, Tectonics and Structure
On 28 March 2005, the Indonesian islands of Nias and Simeulue experienced a powerful Mw 8.6 earthquake and widespread co-seismic uplift and subsidence. In areas of coastal uplift (up to ~2.8 m), fringing reef coral communities were killed by exposure, while deeper corals that survived were subjected to habitats with altered runoff, sediment and nutrient regimes. Here we present time-series [...]
The Role of Continental Heterogeneity on the Evolution of Continental Margin Topography at Subduction Zones
Published: 2023-09-01
Subjects: Earth Sciences, Geophysics and Seismology, Other Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
The nature of the overriding plate plays a major role in shaping subduction zone processes. In particular, the highly heterogeneous continental lithosphere modulates intra-plate tectonics and the surface evolution of our planet. However, the role of continental heterogeneity is relatively under-explored for the dynamics of subduction models. We investigate the influence of rheological and density [...]
Impact of rift history on the structural style of intracontinental rift-inversion orogens
Published: 2023-08-23
Subjects: Earth Sciences, Tectonics and Structure
Although many collisional orogens form after subduction of oceanic lithosphere between two continents, some orogens result from strain localization within a continent via inversion of structures inherited from continental rifting. Intracontinental rift-inversion orogens exhibit a range of structural styles, but the underlying causes of such variability have not been extensively explored. Here, we [...]
Generation of evolving plate boundaries and toroidal flow from visco-plastic damage-rheology mantle convection and continents
Published: 2023-08-17
Subjects: Geology, Geophysics and Seismology, Tectonics and Structure
Earth's style of planetary heat transport is characterized by plate tectonics which requires rock strength to be reduced plastically in order to break an otherwise stagnant lithospheric lid, and for rocks to have a memory of past deformation to account for strain localization and the hysteresis implied by geological sutures. Here, we explore $\sim$10$^7$ Rayleigh number, visco-plastic, [...]
Timing and Evolution of Structures within the Southeastern Greater Caucasus and Kura Fold-Thrust Belt from Multiproxy Sediment Provenance Records
Published: 2023-08-03
Subjects: Earth Sciences, Stratigraphy, Tectonics and Structure
The Greater Caucasus (GC) mountains are the locus of post-Pliocene shortening within the north central Arabia-Eurasia collision. Although recent low-temperature thermochronology constrains the timing of orogen formation, the evolution of major structures remains enigmatic - particularly regarding the internal kinematics within this young orogen and the associated Kura Fold-Thrust Belt (KFTB), [...]