Preprints
Filtering by Subject: Tectonics and Structure
Earthquake faults recorded in the near-shore bathymetry of Japan's back-arc
Published: 2025-04-27
Subjects: Geology, Geomorphology, Geophysics and Seismology, Tectonics and Structure
The eastern margin of the Sea of Japan is a zone of great seismic and tsunami hazard due to multiple offshore and nearshore reverse faults as shown by the 2024 Mw 7.5 Noto Peninsula Earthquake. Here we compare coseismic deformation of the 2024 Noto Peninsula Earthquake with 4767 individual marine terraces spanning the last Myr. This reveals that the earthquake faults started slipping between 326 [...]
Deep source regions for Patagonia backarc volcanism imaged by finite frequency body wave tomography
Published: 2025-04-09
Subjects: Earth Sciences, Geochemistry, Geology, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
The subduction of Chile Ridge beneath South America beginning 12-16 Myr ago opened a gap in the subducting slab beneath southern Patagonia, which migrated northward and is located today at 46oS. Geodynamic processes associated with the slab window are poorly understood. Here we apply finite-frequency P and S body wave tomography to seismic data from several temporary arrays as well as regional [...]
Orogenic architecture diagrams to reconstruct paleogeography and plate tectonics: Newfoundland (Canada) as a case study
Published: 2025-03-17
Subjects: Geology, Tectonics and Structure
Reconstructing paleogeography from accretionary records is challenging due to the difficulty of integrating data sources from different specialized fields. Here, we present the ‘orogenic architecture diagram’ method to systematically compile geological data in temporal and spatial context at the scale of nappes - the ‘building blocks’ of orogens - and to use their interpreted geological histories [...]
Neoproterozoic denudation of a Laurentian superbasin
Published: 2025-02-28
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology, Tectonics and Structure
It has long been speculated that isolated Paleoproterozoic basins of northern Laurentia are remnants of a once contiguous sedimentary cover due to similarities in stratigraphy, paleocurrent directions, sediment provenance, and geochronological data. However, corroborating evidence for this 'superbasin hypothesis' has been lacking outside the footprints of the preserved basins. We present new [...]
A New Interpretation of Ptolemy's Germania Magna: Employing Computer-Assisted Image Distortion of a Medieval Map by Donnus Nicolaus Germanus to Examine Post-Glacial Geodynamics in Europe
Published: 2025-02-02
Subjects: Geology, Geomorphology, Geophysics and Seismology, Nature and Society Relations, Other Astrophysics and Astronomy, Other Earth Sciences, Other Geography, Other Planetary Sciences, Planetary Geology, Planetary Geomorphology, Planetary Geophysics and Seismology, Stratigraphy, Tectonics and Structure, The Sun and the Solar System
This paper revisits Claudius Ptolemy's depiction of Germania Magna through a multidisciplinary approach, integrating computer-aided distortion analysis of Donnus Nicolaus Germanus's medieval cartography with geological insights. The study proposes that the region underwent significant and complex transformations, likely influenced by tectonic activity, such as the reactivation of the Caledonian [...]
Stratigraphic influence on emplacement and 3-dimensional structure of a large mafic sill in sedimentary strata
Published: 2025-01-31
Subjects: Stratigraphy, Tectonics and Structure, Volcanology
Sills are fundamental elements of volcanic plumbing systems emplaced, among other, in sedimentary basins. Even though sills are commonly considered simple, straight concordant igneous sheets, they are actually complex 3-dimensional objects. The detailed knowledge of the 3D structure of sills and their host rock is of primary relevance to better constraining the emplacement mechanisms and the [...]
Insights into plume-ridge-transform fault interactions as derived from 3D numerical geodynamic modelling of the Azores Triple Junction
Published: 2025-01-31
Subjects: Geology, Tectonics and Structure
The Azores Archipelago is an igneous province located in the centre of the Atlantic Ocean marked by a large bathymetric plateau with a complex tectonic history. Over the last 10 Myr, this region has been shaped by the interaction between the Azores plume, the Mid-Atlantic Ridge (MAR), and the Gloria Fault zone. This complex interaction was characterised namely by the transition from a [...]
Fingerprinting subduction margins using PCA profiles: A data science approach to assessing earthquake hazard
Published: 2025-01-21
Subjects: Earth Sciences, Statistical Methodology, Statistical Models, Tectonics and Structure
Giant earthquakes (MW ≥ 8.5) along subduction margins pose great hazards to coastal societies. While it is generally accepted that geological margin properties play a role, the controls on giant earthquake occurrence remain undetermined. Their long intermittence times and the comparatively short earthquake record obscure any correlations between margin properties and seismicity. This work [...]
A semi-automated method for constructing three-dimensional models of complex fault networks
Published: 2025-01-10
Subjects: Earth Sciences, Geophysics and Seismology, Tectonics and Structure
Fault geometry and the connectivity between faults at depth are both important controls on the nucleation, propagation and arrest of earthquake rupture, so modelling these parameters accurately is essential to models of the earthquake cycle. However, simulations involving complex three-dimensional (3D) fault systems rarely explore the sensitivity of results to uncertainties in geometry and [...]
Transtension in the Levant Basin: Challenging the Syrian Arc model
Published: 2025-01-09
Subjects: Geology, Stratigraphy, Tectonics and Structure
Late Cretaceous intra-plate shortening, and inversion of the Permian to Jurassic rift system, resulted in the ~1000 km-long, S-shaped Syrian Arc Fold Belt which dominates the Levant regional topography through Egypt, Israel, Lebanon, and Syria. Subsequent Miocene folding along the same trends of the Late Cretaceous fold belt, was likely associated with the collision of Arabia and Eurasia. The [...]
Is the Suez Rift in its post-rift phase?
Published: 2025-01-03
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Tectonics and Structure
Failed rifts are widely assumed to enter post-rift quiescence after termination of intracontinental rifting. However, this remains largely untested and a comprehensive evaluation of the rates and patterns of post-rift tectonic (in)activity is lacking. Our novel, rift-scale geomorphic analysis reveals “post-rift” rifting across the archetypal failed rift of Suez, in Egypt. Stacked topographic [...]
Cambrian foreland phosphogenesis in the Khuvsgul Basin of Mongolia
Published: 2024-12-27
Subjects: Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy, Tectonics and Structure
Ediacaran-Cambrian phosphorite deposits in northern Mongolia have been associated with a putative increase in nutrient delivery to the global oceans that drove oxygenation and the rise of animals. However, like many phosphorites from this ~130 Myr interval, the precise age and depositional setting of these deposits remain poorly constrained. Here, we integrate new geological mapping, [...]
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 [...]