Preprints
Filtering by Subject: Tectonics and Structure
Mid- to Late Neoproterozoic Development and Provenance of the Adelaide Superbasin
Published: 2022-03-23
Subjects: Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy, Tectonics and Structure
Late Tonian sequences of the Adelaide Superbasin were witness to the birth of the proto-Pacific Ocean during the breakup of Rodinia. Understanding the sedimentology and provenance of these rocks from across the basin is key to understanding their deposition over c. 70 million years, the local palaeogeography, and leads to a better understanding of the early development of the proto-Pacific Ocean. [...]
Internal Planetary Feedbacks, Mantle Dynamics, and Plate Tectonics
Published: 2022-03-19
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Planetary Geophysics and Seismology, Planetary Sciences, Tectonics and Structure
Isolating planetary feedbacks, and feedback analysis, are prevalent aspects of climate and Earth surface process science. An under appreciation of internal planet feedbacks, and feedback analysis for plate tectonics research, motivate this chapter. We review feedbacks that influence the Earth's thermal evolution and expand them to include magmatic history and planetary water budgets. The [...]
Self-replicating subduction zone initiation by polarity reversal
Published: 2022-03-16
Subjects: Earth Sciences, Geology, Tectonics and Structure
Subduction zones have recurrently formed on Earth. Previous studies have, however, suggested that they are unlikely to start in the interior of a pristine ocean. Instead, they seem to be more likely to form from another pre-existing subduction zone. One widely cited conceptual model to start new subduction zones is polarity reversal, resulting from the shutdown of a pre-existent subduction zone [...]
The development of the eastern Orpheus rift basin, offshore eastern Canada: A case study of the interplay between rift-related faulting and salt deposition and flow
Published: 2022-03-12
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
The salt-rich Orpheus rift basin, part of the eastern North American (ENAM) rift system, formed during the Late Triassic to Early Jurassic prior to opening of the Atlantic Ocean. Using a dense grid of 2D seismic-reflection lines, data from nearby wells, and information from adjacent ENAM rift basins, we have established a tectonostratigraphic framework, identified key structural elements, and [...]
Geodynamics of continental rift initiation and evolution
Published: 2022-03-07
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Tectonics and Structure
A rift is a nascent plate boundary where continental lithosphere is extended and possibly broken. In the geologic past, rifting played a major role in shaping the surface of our planet, while at present, continental rifts are of societal relevance by hosting key georesources such as geothermal energy and ore deposits. This Review discusses fundamental rift processes, geodynamic forces and their [...]
Origin and kinematics of a basin-scale, non-polygonal, layer-bound normal fault system in the Levant Basin, eastern Mediterranean
Published: 2022-02-28
Subjects: Geology, Tectonics and Structure
Polygonal, layer-bound normal faults can extend over very large areas (>2,000,000 km2) of sedimentary basins. Best developed in very fine-grained rocks, these faults are thought to form during early burial in response to a range of diagenetic processes, including compaction and water expulsion. Local deviations from this idealised polygonal pattern are common; however, basin-scale, layer-bound [...]
Fault slip-rates and Coulomb stress interactions in the intersection zone of the Hope, Kelly and Alpine Faults, South Island, New Zealand
Published: 2022-02-25
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Tectonics and Structure
The Hope Fault is a major strike-slip plate boundary fault in the Marlborough Fault Zone of New Zealand’s South Island that transfers slip between the Alpine Fault and Hikurangi subduction zone. We use lidar-based geomorphic and fault mapping, and optically stimulated luminescence (OSL; quartz) and infrared stimulated luminescence (IRSL; feldspar) dating of fault-proximal sedimentary deposits to [...]
Along-Dip Segmentation of the Slip Behavior and Rheology of the Copiapó Ridge Subducted in North-Central Chile
Published: 2022-02-24
Subjects: Geology, Geophysics and Seismology, Tectonics and Structure
We studied the along-dip influence of the Copiapó ridge subduction in the Atacama region, North-Central Chile by building a new seismicity catalog, including similar events and non-volcanic tremors (NVTs). We also obtained a 3-D tomographic model for P- and S-waves velocity (and the implied Vp/Vs ratio). We identify down-dip segmentation involving 4 distinct segments: a locked seismogenic zone [...]
Early evolution of the Adelaide Superbasin
Published: 2022-02-17
Subjects: Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy, Tectonics and Structure
Continental rifts have a significant role in supercontinent breakup, and the development of sedimentary basins. The Australian Adelaide Superbasin is one of the largest and best-preserved rift systems that initiated during the breakup of Rodinia, yet substantial challenges still hinder our understanding of its early evolution and place within the Rodinian supercontinent. In the past decade, our [...]
Macrostratigraphy of the Ediacaran System in North America
Published: 2022-02-11
Subjects: Earth Sciences, Geochemistry, Geology, Paleontology, Sedimentology, Stratigraphy, Tectonics and Structure
Ediacaran sediments record the termination of Cryogenian ‘Snowball Earth’ glaciations, preserve the first occurrences of macroscopic metazoans, and contain one of the largest known negative δ13C excursions (the Shuram-Wonoka). The rock record for the transition between the Proterozoic and Phanerozoic in North America is also physically distinct, with much of the continent characterized by a wide [...]
S-wave modeling of the Showa-Shinzan lava dome in Usu Volcano, Northern Japan, from seismic observations
Published: 2022-02-09
Subjects: Geophysics and Seismology, Tectonics and Structure, Volcanology
To obtain an internal S-wave velocity structure, we conducted a passive seismic campaign with 21 1-Hz seismometers on and around the Showa-Shinzan lava dome, which emerged during the 1943–1945 eruption of Usu Volcano, Japan. Before the campaign, we calibrated seismometers and found slight phase-response differences between seismometers of less than 1–2 degrees. After the campaign, we extracted [...]
Indian Plate paleogeography, subduction, and horizontal underthrusting below Tibet: paradoxes, controvercies, and opportunities
Published: 2022-02-06
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Sedimentology, Tectonics and Structure, Volcanology
The India-Asia collision zone is the archetype to calibrate geological responses of continent-continent collision, but hosts a paradox: there is no orogen-wide geological record of oceanic subduction after initial collision around 60-55 Ma, yet thousands of kilometers of post-collisional subduction occurred before arrival of unsubductable continental lithosphere that currently horizontally [...]
Trench migration and slab buckling control the formation of the Central Andes
Published: 2022-02-04
Subjects: Geophysics and Seismology, Other Earth Sciences, Tectonics and Structure
The formation of the Central Andes dates back to ~50 Ma, but its most pronounced phase, including the growth of the Altiplano-Puna Plateau and pulsatile tectonic shortening phases, occurred within the last 25 Ma. The reason for this evolution remains unexplained. Using geodynamic numerical modeling we infer that the primary cause of the pulses of tectonic shortening and growth of Central Andes is [...]
Quaternary E-W extension uplifts Kythira Island and segments the Hellenic Arc
Published: 2022-01-25
Subjects: Geology, Geomorphology, Paleontology, Sedimentology, Stratigraphy, Tectonics and Structure
Several crustal and lithospheric mechanisms lead to deformation and vertical motion of the upper plate during subduction, but their relative contribution is often enigmatic. Multiple areas of the Hellenic Forearc have been uplifting since Plio-Quaternary times, yet spatiotemporal characteristics and sources of this uplift are poorly resolved. The remarkable geology and geomorphology of Kythira [...]
Phanerozoic sedimentary cover history of the Hudson Platform: a heuristic modeling perspective
Published: 2022-01-19
Subjects: Earth Sciences, Geochemistry, Geology, Geomorphology, Physical Sciences and Mathematics, Stratigraphy, Tectonics and Structure
Understanding the long-term erosion and burial history of cratons is challenging due to the incompleteness of the rock record. Low-temperature thermochronology is used to elucidate these surface histories by inverting thermochronological data for the time-temperature history and incorporating sparse constraints and other assumptions about the regional geologic evolution. However, imposing certain [...]