Preprints
Filtering by Subject: Stratigraphy
A very unconventional hydrocarbon play: the Mesoproterozoic Velkerri Formation of Northern Australia
Published: 2022-05-16
Subjects: Geochemistry, Geology, Sedimentology, Stratigraphy, Tectonics and Structure
The ca. 1.5–1.3 Ga Roper Group of the greater McArthur Basin is a component of one of the most extensive Precambrian hydrocarbon-bearing basins preserved in the geological record, recently assessed as containing 429 million barrels of oil and eight trillion cubic feet of gas (in place). It was deposited in an intra-cratonic sea, referred to here as the McArthur-Yanliao Gulf. The Velkerri [...]
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 [...]
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 identified over a century ago, and its global significance was recognised shortly after, eventually culminating with the 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, [...]
Late Tonian development and provenance of the Adelaide Superbasin
Published: 2022-03-22
Subjects: Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy, Tectonics and Structure
The 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 both their deposition over ~70 million years, the local palaeogeography, and leads to a better understanding of the early development of the proto-Pacific [...]
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 [...]
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 [...]
A one-million-year isotope record from siderites formed in modern ferruginous sediments
Published: 2022-02-17
Subjects: Biogeochemistry, Other Environmental Sciences, Sedimentology, Stratigraphy
Ancient iron formations hold important records of environmental conditions during the Precambrian Eons. Reconstructions of past oceanic systems require investigating modern ferruginous analogs to disentangle water column and diagenetic signals recorded in iron-bearing minerals. We analyzed oxygen, iron, and carbon isotopes in siderite, a ferrous carbonate phase commonly used as an environmental [...]
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 [...]
Seismic Geomorphology of a Late Cretaceous Turbidite Channel system in Deepwater Kribi/Campo sub-basin, offshore Cameroon
Published: 2022-01-28
Subjects: Earth Sciences, Geology, Geomorphology, Geophysics and Seismology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
In this study, a seismic reflection dataset and well-log data were integrated to investigate the geometry and internal configuration of a turbidite channel system within the Late Cretaceous interval of the deep-water Kribi-Campo sub-basin, offshore Cameroon. This interval is characterized by a well-developed submarine channel system consisting of an early and a late-stage channel. [...]
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 [...]
Calibrating the temporal and spatial dynamics of the Ediacaran - Cambrian radiation of animals
Published: 2021-12-31
Subjects: Geochemistry, Geology, Paleontology, Stratigraphy
The Ediacaran-Cambrian transition, which incorporates the radiation of animals, lacks a robust global temporal and spatial framework, resulting in major uncertainty in the evolutionary dynamics of this critical radiation and its relationship to changes in palaeoenvironmental geochemistry. We first present a new δ13Ccarb composite reference curve for the Ediacaran Nama Group of southern Namibia, [...]
Structural traps and seals for expanding CO2 storage in the northern Horda Platform, North Sea
Published: 2021-12-24
Subjects: Geology, Geophysics and Seismology, Oil, Gas, and Energy, Other Earth Sciences, Other Environmental Sciences, Stratigraphy, Tectonics and Structure
The maturation of geological CCS along the Norwegian Continental Shelf is ongoing in the Norwegian North Sea, however, more storage sites are needed to reach climate mitigation goals by 2050. In order to augment the Aurora site and expand CO2 storage in the northern Horda Platform, regional traps and seals must be assessed to better understand the area’s potential. Here, we leverage wellbore and [...]
Downward-propagating eruption following vent unloading implies no direct magmatic trigger for the 2018 lateral collapse of Anak Krakatau
Published: 2021-12-18
Subjects: Earth Sciences, Stratigraphy, Volcanology
The lateral collapse of Anak Krakatau volcano, Indonesia, in December 2018 highlighted the potentially devastating impacts of volcanic edifice instability. Nonetheless, the trigger for the Anak Krakatau collapse remains obscure. The volcano had been erupting for the previous six months, and although failure was followed by intense explosive activity, it is the period immediately prior to collapse [...]
Hermann Löns’ “Quintär” – an early approach to the geological stratigraphy of the Age of Humans and its significance in geosciences
Published: 2021-12-16
Subjects: Earth Sciences, Geology, Other Earth Sciences, Stratigraphy
In 1908, Hermann Löns outlined the concept of a Quintär” (“Quintary period”) to describe geological and biological manifestations of the Age of Humans. His definition of the “Quintary” consisted of two components: a lithostratigraphic (“Quintary deposits” or “Quintary stratum”), and a faunistic (“Quintary fauna”) one. With a view on the stratigraphic component, Löns already anticipated the [...]