Preprints
Filtering by Subject: Tectonics and Structure
Temporal variation in counterclockwise vertical-axis block rotations across a rift overlap zone, southwestern Ethiopia, East Africa
Published: 2024-12-18
Subjects: Tectonics and Structure
The southward propagation of the southern Main Ethiopian Rift (sMER) and the northward propagation of the Kenya Rift have generated the Broadly Rifted Zone (BRZ), a ~40-km-wide region of extensional overlap between the Chew Bahir Basin-Gofa Province and the sMER. However, the tectonic interaction between these propagating rifts is not well-understood. We present new paleomagnetic and [...]
Leaky faults modulated magma ascent and seismicity during the 2022 São Jorge (Azores) volcanic unrest
Published: 2024-12-16
Subjects: Earth Sciences, Geophysics and Seismology, Tectonics and Structure, Volcanology
Understanding the signatures and mechanisms of failed volcanic eruptions is vital for mapping magma plumbing systems and forecasting volcanic hazards. Geological structures like fractures and faults are key to guiding magma, but their mechanisms remain unclear due to limited 3-D mapping of faults in volcanic regions and sufficiently precise earthquake locations. The triple-junction setting of the [...]
Evidence for large disturbances of the Ediacaran geomagnetic field from West Africa
Published: 2024-11-27
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Constraining the paleogeography of the Ediacaran is crucial for understanding the extensive tectonic, biological and geochemical changes that occurred during that epoch. Paleomagnetism is an essential tool for reconstructing the Ediacaran paleogeography but it is complicated because the paleomagnetic data of that age display unusually fast and large directional oscillations. Two main competing [...]
Minibasin dynamics control sediment dispersal on a salt-detached slope: examples from the Northern Gulf of Mexico
Published: 2024-11-22
Subjects: Earth Sciences, Geology, Tectonics and Structure
Basal welds can halt the downslope translation of minibasins on salt-detached slopes, commonly giving rise to shortening and extension, updip and downdip, respectively, of the obstructed minibasins. How minibasin obstruction influences seafloor topography and thus deep-water sediment dispersal has not been previously investigated, despite it being an important control on hydrocarbon reservoir [...]
Oligocene – Miocene Tectono-Stratigraphic Development of the Southern Levant Basin, Eastern Mediterranean
Published: 2024-11-20
Subjects: Geology, Stratigraphy, Tectonics and Structure
The Levant Basin, Eastern Mediterranean, has a complex geological history. The separation of Africa from Arabia, and the collision of the latter with Eurasia during the Oligocene – Miocene had significant implications for the tectono-stratigraphy of the region, as recorded in the thick, siliciclastic-dominated sequence preserved in the Levant Basin. Previous studies mostly focused on either [...]
Numerical modelling of lithosphere-asthenosphere interaction and intraplate deformation in the Gulf of Guinea
Published: 2024-10-31
Subjects: Geology, Geophysics and Seismology, Tectonics and Structure
To present day, the phenomenon of intraplate deformation and its associated earthquakes remain elusive. In this work, we argue that intraplate deformation may result from the interaction between lithospheric and upper mantle dynamic processes. To this extent, we targeted the Gulf of Guinea and adjacent Western Africa, a region with both low plate velocities and clear asthenosphere dynamics, [...]
Interseismic deformation fingerprints on the hyperarid coastal landscape in North Chilean subduction
Published: 2024-10-10
Subjects: Earth Sciences, Geology, Geomorphology, Geophysics and Seismology, Tectonics and Structure
Along-strike seismotectonic behavior of subduction megathrusts feeds back into the forearc deformation as elastic and permanent deformation. However, whether and how short-term elastic deformation reflects long-term permanent deformation in the forearc and shapes the coastal region remains unclear. To evaluate the forearc deformation, we analyze the interseismic surface deformation obtained from [...]
Guidelines for Sensitivity Analyses in Process Simulations for Solid Earth Geosciences
Published: 2024-09-18
Subjects: Applied Mathematics, Earth Sciences, Education, Partial Differential Equations, Physical Sciences and Mathematics, Science and Mathematics Education, Tectonics and Structure
Numerical simulations are widely used as tools to understand processes or to make predictions about states and their evolution in time. However, in the process of a simulation setup, a multitude of choices and simplifications have to be made - beginning from the definition of the implemented physical laws, over model discretization and spatial parameterisation, to the definition of initial and [...]
Evidence supporting a broader than previously thought influence of solar activity over Earth system’s processes. Discussion of a possible mechanism.
Published: 2024-09-08
Subjects: Atmospheric Sciences, Earth Sciences, Geochemistry, Geology, Geophysics and Seismology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Tectonics and Structure, Volcanology
In this article, I show lines of evidence supporting a modulation of volcanic activity and some weather phenomena by solar wind conditions in the near-Earth environment. On a daily timescale, a correlation is found between the LP earthquake activity of Kilauea volcano, related to magma transport, and the Bx component of the interplanetary magnetic field as measured in the OMNI database for [...]
Simultaneous deformation along the Main Ethiopian Rift and associated transversal lineaments: an analogue modelling perspective
Published: 2024-08-30
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
The interaction between the NE-SW striking Main Ethiopian Rift (MER) and the E-W oriented Yerrer-Tullu Wellel Volcano-tectonic lineament (YTVL) represents one of the least understood tectonic problems in the East African Rift System. Despite the numerous studies that have been conducted in the region, the following questions still remain to be answered: did the MER and YTVL evolve simultaneously? [...]
The Origin of Forearc Depressions
Published: 2024-08-23
Subjects: Earth Sciences, Geology, Sedimentology, Tectonics and Structure
Forearc depressions form over continental subduction zones with young, slowly subducting slabs and thick trench fills. They are bound seaward by a coast range and landward by a volcanic arc such that subsidence in forearc depressions occurs between orogens and in areas characterized by plate convergence. We propose a model for forearc depression formation based on geophysical and seismic data [...]
Complex and confined laboratory ruptures explain scaling of the critical slip distance for earthquake faulting
Published: 2024-08-22
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Earthquake sequences in nature are complex, exhibiting a range of magnitudes and slip behaviors. In contrast, earthquake-like instabilities generated on frictional faults in the laboratory and in continuum numerical models are usually quasi-periodic with a smaller range of magnitudes and durations. The discrepancy, especially apparent for cm-sized samples used in lab friction experiments, has [...]
The cyclical nature of normal fault growth: Insights from 4D analogue models
Published: 2024-08-10
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Exploring how normal faults evolve is important for understanding the dynamic processes underlying the initiation and evolution of rift systems. Early-stage fault growth has been largely under-explored due to resolution limitations in seismic reflection data and the lack of three-dimensional exposures in the field. Physical analogue modelling offers a unique way to visualize and analyse [...]
Tomotectonics of Cordilleran North America since Jurassic times: double-sided subduction, archipelago collisions, and Baja-BC translation
Published: 2024-07-27
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Tomotectonics uses deep mantle structure in order to hindcast paleo-trenches, by spatially superposing subducted lithosphere (slabs) imaged by seismic tomography with plate reconstructions at the surface. The two geophysical datasets combined make predictions about geologic events, specifically about volcanic arcs and their collisions with continents. The tomotectonic null hypothesis is simple, [...]
Quantifying relationships between fault parameters and rupture characteristics associated with thrust and reverse fault earthquakes.
Published: 2024-07-12
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 [...]