Filtering by Subject: Tectonics and Structure

Quantifying relationships between fault parameters and rupture characteristics associated with thrust and reverse fault earthquakes.

Kristen Chiama, William Bednarz, Robb Moss, et al.

Published: 2024-07-11
Subjects: Geology, Geomorphology, Geophysics and Seismology, Geotechnical Engineering, Risk Analysis, Tectonics and Structure

We investigate the influence of earthquake source characteristics and geological site parameters on fault scarp morphologies for thrust and reverse fault earthquakes using geomechanical models. We performed a total of 3,434 distinct element method (DEM) model experiments to evaluate the impact of the sediment depth, density, homogeneous and heterogeneous sediment strengths, fault dip, and the [...]

Synchrotron radiation reveals transient weakening during mineral phase transformations

Andrew J. Cross, Rellie Goddard, Kathryn M Kumamoto, et al.

Published: 2024-05-13
Subjects: Earth Sciences, Geology, Mineral Physics, Tectonics and Structure

Phase transformations are widely invoked as a source of rheological weakening during subduction, continental collision, mantle convection, and various other geodynamic phenomena. However, the likelihood and magnitude of such weakening in nature remains undetermined. Here, experiments performed on a synchrotron beamline reveal dramatic weakening across the polymorphic quartz↔coesite phase [...]

The influence of a sub-lithospheric layer width on the partitioning of the induced mantle flow, surface motions and subduction dynamics

Roberta Carluccio, Louis N. Moresi, Fabio Capitanio, et al.

Published: 2024-04-17
Subjects: Geophysics and Seismology, Other Earth Sciences, Planetary Geology, Tectonics and Structure

The partitioning of the three-dimensional mantle flow into toroidal and poloidal components is a diagnostic element to characterise tectonics regimes, with both fields being substantially active and representative of the contemporary mode of mantle convection. The toroidal:poloidal ratio (T/P) affects several aspects of mantle circulation, including the sinking of the subducting lithosphere into [...]

Digitising sandbox experiments using open-source Structure-from-Motion/photogrammetry/Digital Image Correlation package MicMac

Olivier Galland, Luc Girod, Sonja Greiner, et al.

Published: 2024-04-15
Subjects: Geology, Geophysics and Seismology, Tectonics and Structure, Volcanology

Structure-from-Motion and photogrammetry have been implemented in sandbox models to monitor deformation of their surface. Various software packages are available, either open-source of commercial. Some commercial packages are intuitive press-button equipment; these can be very practical to use, but they can be very expensive and unaffordable for most academic laboratories. Another option is [...]

Evolution and architecture of an exhumed ocean-facing coarse-grained submarine canyon fill, Baja California, Mexico

Max Bouwmeester, Ian Kane, David Hodgson, et al.

Published: 2024-04-15
Subjects: Earth Sciences, Geology, Sedimentology, Stratigraphy, Tectonics and Structure

Present day submarine canyons are active conduits for large volumes of sediment, carbon, and pollutants from continents to oceans. However, the evolution of submarine canyons over geological timescales remains poorly understood due to their erosional nature and low preservation potential. The Late Cretaceous Punta Baja Formation represents a well-preserved submarine canyon-fill on a [...]

Brittle origin of off-fault fractures during the 2019 Ridgecrest earthquake sequence

Enrico Milanese, Camilla Cattania

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

Clara Abu, Christopher Aiden-Lee Jackson

Published: 2024-03-03
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

Gino de Gelder, Navid Hedjazian, Laurent Husson, et al.

Published: 2024-02-09
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

Karla Rubio-Sandoval, Deirdre D. Ryan, Sebastian Richiano, et al.

Published: 2024-01-19
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)

Zoe K Mildon, Manuel-lukas Diercks, Gerald P Roberts, et al.

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

Arnab Roy, Nibir Mandal, Jeroen van Hunen

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

Alan D. Chapman, Jennifer Grischuk, Meghan Klapper, et al.

Published: 2024-01-10
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

Nicolas Coltice, Simon Blessing, Ralph Giering, et al.

Published: 2023-12-10
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

Bob Bamberg, Marc Reichow, Richard Walker, et al.

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

Billy Andrews, Zoe K Mildon, Christopher Aiden-Lee Jackson, et al.

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% [...]


You can search by:

  • Title
  • Keywords
  • Author Name
  • Author Affiliation