Preprints
Filtering by Subject: Tectonics and Structure
Fault rupture during the December 26, 2018, Mw 4.9 Fleri earthquake (Mt. Etna): surface faulting in a volcano-tectonic environment
Published: 2020-02-04
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
On December 26, 2018, the largest instrumental earthquake ever recorded in Mt. Etna (Sicily, southern Italy) shook the eastern flank of the volcano, with epicenter near the Fleri village along the right-lateral Fiandaca Fault (focal depth less than 1 km, Mw 4.9). The mainshock was accompanied by widespread surface faulting. We surveyed and mapped the coseismic ground ruptures and collected [...]
High-resolution surface velocities and strain for Anatolia from Sentinel-1 InSAR and GNSS data
Published: 2020-02-04
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Measurements of present-day surface deformation are essential for the assessment of long-term seismic hazard. The European Space Agencys Sentinel-1 satellites enable global, high-resolution observation of crustal motion from Interferometric Synthetic Aperture Radar (InSAR). We have developed new automated InSAR processing systems that exploit the first ~5 years of Sentinel-1 data to measure [...]
Avalonia, get bent! Paleomagnetism from SW Iberia confirms the Greater Cantabrian Orocline
Published: 2020-01-29
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
The amalgamation of Pangea formed the contorted Variscan-Alleghanian orogen, suturing Gondwana and Laurussia during the Carboniferous. From all swirls of this orogen, a double curve stands out in Iberia, the coupled Cantabrian Orocline and Central Iberian Curve. The Cantabrian Orocline formed subsequent to Variscan orogeny (ca. 315-295 Ma). The mechanisms of formation for this orocline are [...]
The mixology of precursory strain partitioning approaching brittle failure in rocks
Published: 2020-01-08
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
We examine the strain accumulation and localization process throughout twelve triaxial compression experiments on six rock types deformed in an X-ray transparent apparatus. In each experiment, we acquire 50-100 tomograms of rock samples at differential stress steps during loading, revealing the evolving 3D distribution of X-ray absorption contrasts, indicative of density. Using digital volume [...]
Active deformation and Plio-Pleistocene fluvial reorganization of the western Kura Fold-Thrust Belt, Georgia: implications for the evolution of the Greater Caucasus mountains and seismic hazard
Published: 2019-12-31
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Tectonics and Structure
Since the Plio-Pleistocene, southward migration of shortening in the eastern part of the Greater Caucasus (GC) into the Kura foreland basin has progressively formed the Kura-Fold Thrust belt (KFTB) and Alazani piggyback basin, which separates the KFTB from the GC. Previous work argued for an eastward propagation of the KFTB, implying that the western portion in Georgia is the oldest, but this [...]
Back-propagating super-shear rupture in the 2016 Mw7.1 Romanche transform fault earthquake
Published: 2019-12-26
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
How an earthquake rupture propagates strongly influences potentially destructive ground shaking. Complex ruptures often involve slip along multiple faults, masking information on the frictional behaviour of fault zones. Geometrically smooth ocean transform fault plate boundaries offer a favourable environment to study fault dynamics, because strain is accommodated along a single, wide fault zone [...]
Stratigraphic reservoir compartmentalization: causes, recognition, and implications for the geological storage of carbon dioxide
Published: 2019-11-22
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Tectonics and Structure
The impact of carbon capture and storage (CCS) in mitigating anthropogenic emissions of greenhouse gases is potentially great, but its success is strongly dependent on identifying suitable geological storage sites. One of the key uncertainties in this regard is the degree of compartmentalization of the target storage horizon. Many studies have examined reservoir compartmentalization in oil and [...]
Ancient subducted oceans controlling the positioning of deep mantle plumes
Published: 2019-11-08
Subjects: Earth Sciences, Geochemistry, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Seismic imaging of the Earths interior reveals plumes originating from relatively hot regions of the lower mantle, surrounded by cooler material thought to be remnants of ancient subducted oceans. Based largely on geophysical data, two opposing hypotheses dominate the discussion on dynamics at the base of mantle: the large hot anomalies are thermo-chemical in nature; or, alternatively, they are [...]
Growth, overprinting, and stabilization of Proterozoic Provinces in the southern Lake Superior region
Published: 2019-11-08
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Tectonics and Structure
New geochronologic data in the southern Lake Superior region provide key information on the timing and nature of tectonic activity that pre-and post-date initial Paleoproterozoic growth of Laurentia during the geon 18 Penokean orogeny. The obducted Pembine ophiolite formed along the edge of a Paleoproterozoic ocean basin at least 30 m.y. prior to Penokean island arc/microcontinent accretion [...]
The variation and visualisation of elastic anisotropy in rock-forming minerals
Published: 2019-10-31
Subjects: Earth Sciences, Geochemistry, Geology, Geophysics and Seismology, Mineral Physics, Physical Sciences and Mathematics, Tectonics and Structure
All minerals behave elastically, a rheological property that controls their ability to support stress, strain and pressure, the nature of acoustic wave propagation and influences subsequent plastic (i.e. permanent, non-reversible) deformation. All minerals are intrinsically anisotropic in their elastic properties – that is, they have directional variations that are related to the configuration [...]
Surface faulting earthquake clustering controlled by fault and shear-zone interactions
Published: 2019-10-25
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Surface faulting earthquakes are known to cluster in time, from historical and palaeoseismic studies, but the mechanism(s) responsible for clustering, such as fault interaction, strain-storage, and evolving dynamic topography, are poorly quantified, and hence not well understood. We present a quantified replication of observed earthquake clustering in central Italy. Six active normal faults are [...]
Inheritance of penetrative basement anisotropies by extension-oblique faults: Insights from analogue experiments
Published: 2019-10-24
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
During rifting, pre-existing penetrative basement fabrics can affect new faults in cover rocks by a mechanism that does not appear to involve reactivation. This subtle form of inheritance can significantly impact fault network architecture in rift basins above laterally variable basement domains with geomechanical anisotropies. Here we use multi-layer, brittle-ductile, crustal-scale analogue [...]
Dynamic fault parameters preprint
Published: 2019-10-24
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
The behavior of faults under dynamic loading reflects the response of the shape and composition of the fault to the applied mechanical loading and environmental conditions. The interaction between the fault properties and the loading system is controlled by multiple variables that may generate an inherently complex behavior. The usage of multi-parametric variables can illuminate the controlling [...]
Distributed normal faulting in the tip zone of the South Alkyonides Fault System, Gulf of Corinth, constrained using 36Cl exposure dating of Late-Quaternary wave-cut platforms.
Published: 2019-10-24
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
In order to investigate the geometry, rates and kinematics of active faulting in the region close to the tip of a major crustal-scale normal fault in the Gulf of Corinth, Greece, we have mapped faults and dated their offsets using a combination of 234U/230Th coral dates and in situ 36Cl cosmogenic exposure ages for sediments and wave-cut platforms deformed by the faults. Our results show that [...]
Pre-breakup extension in the northern North Sea defined by complex strain partitioning and heterogeneous extension rates
Published: 2019-10-24
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
The early stages of continental rifting are accommodated by the growth of upper-crustal normal fault systems that are distributed relatively evenly across the rift width. Numerous fault systems define fault arrays, the kinematics of which are poorly understood due to a lack of regional studies drawing on high-quality subsurface data. Here we investigate the long-term (~150 Myr) growth of a [...]