Preprints
Filtering by Subject: Geology
Late Glacial and Holocene Palaeolake History of the Última Esperanza Region of Southern Patagonia
Published: 2022-03-29
Subjects: Earth Sciences, Geochemistry, Geology, Geomorphology, Glaciology, Hydrology, Paleobiology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Volcanology
We undertook multiproxy analyses on two sediment cores from Lago Pato, a small lake basin at 51°S topographically separated from Lago del Toro in Torres del Paine (TdP), to provide insights into glacier dynamics and lake level change in the TdP and Última Esperanza region over the last ~30,000 cal a BP (30 ka). Lago Pato is situated in a region overridden by the Southern Patagonian Icefield [...]
Coastal River Response to Transgression: A New Look at the Trinity Incised Valley Using Multi-Resolution Seismic Imaging
Published: 2022-03-29
Subjects: Earth Sciences, Geology, Geomorphology, Geophysics and Seismology, Sedimentology
Modern lowland river systems show transitions in flow characteristics near coastlines that lead to systematic changes in sediment deposition and stratigraphic architecture. Sensitivity of fluvial morphodynamics to base-level has important implications for the prediction and interpretation of fluvial stratigraphy, particularly in deposits formed during periods of relative sea-level rise such as [...]
CCC - integrated multiscale study of salt cavern abandonment in the Netherlands
Published: 2022-03-24
Subjects: Geology, Geophysics and Seismology, Materials Science and Engineering, Mineral Physics, Mining Engineering, Other Earth Sciences, Tectonics and Structure
The KEM-17 project of the Dutch State Supervision of Mines presented a critical review of concepts of cavern abandonment and related science. It recommended that analyses of cavern abandonment are done as an integrated project, addressing (i) micro-scale physical processes, (ii) cavern scale models based on field scale experiments and numerical models, (iii) the salt dome scale, to model the far [...]
Geochronology and formal stratigraphy of the Sturtian Glaciation in the Adelaide Superbasin
Published: 2022-03-24
Subjects: Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy
The glaciogenic nature of the Yudnamutana Subgroup was first recognized over a century ago, and its global significance was recognized shortly after, with the eventual postulation of a global Sturtian Glaciation and Snowball Earth theory. Much debate on the origin and timing of these rocks, locally and globally, has ensued in the years since. A significant corpus of research on the lithology, [...]
Mid- to Late Neoproterozoic Development and Provenance of the Adelaide Superbasin
Published: 2022-03-22
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. [...]
Self-replicating subduction zone initiation by polarity reversal
Published: 2022-03-15
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: 2022-03-11
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 [...]
Paleocene to Miocene southern Tethyan carbonate factories of the Southwestern and Western Central Asia
Published: 2022-03-11
Subjects: Geology, Paleobiology, Paleontology, Sedimentology
One hundred and forty-four sections of shallow-water carbonates, deposited between the Paleocene and the Miocene, from the Levant to the Himalaya, have been investigated to analyze the distribution of carbonate facies and carbonate producing organisms. Large benthic foraminifera resulted the volumetrically most important group of carbonate producers during the whole period, with a peak in [...]
Inverting passive margin stratigraphy for marine sediment transport dynamics over geologic time
Published: 2022-03-09
Subjects: Geology, Geomorphology, Sedimentology, Stratigraphy
Passive margin stratigraphy contains time-integrated records of landscapes that have long since vanished. Quantitatively reading the stratigraphic record using coupled landscape evolution and stratigraphic forward models (SFMs) is a promising approach to extracting information about landscape history. However, there is no consensus about the optimal form of simple SFMs because there has been a [...]
Geodynamics of continental rift initiation and evolution
Published: 2022-03-06
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 [...]
Magma chamber detected beneath an arc volcano with high-resolution velocity images
Published: 2022-03-05
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Volcanology
Arc volcanoes are underlain by complex systems of molten-rock reservoirs ranging from melt-poor mush zones to melt-rich magma chambers. Petrological and satellite data indicate that eruptible magma chambers form in the topmost few kilometres of the crust. However, very few chambers have ever been definitively located, suggesting that most are too short-lived or too small to be imaged, which has [...]
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: 2022-02-24
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: 2022-02-16
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 [...]