Preprints
Filtering by Subject: Geology
Shallow storage conditions at Krafla IDDP-1 revealed by rhyolite-MELTS geobarometry, and implications for global shallow magmatism
Published: 2024-06-24
Subjects: Earth Sciences, Geochemistry, Geology, Other Earth Sciences, Volcanology
Identifying the storage depths of melt-dominated magma bodies prior to eruption is critical for understanding magma transport, eruption hazards, and magma body longevity. Rhyolite-MELTS has been used effectively to calculate pre-eruptive storage pressures for silicic magma bodies in the upper crust (~100-350 MPa), but its precision and accuracy in very low-pressure systems (<100 MPa) has not [...]
Paleohydrology of North American Catchments and Rivers at the Onset of the Eocene-Oligocene Climate Transition: Reconstructions from Fluvial Strata of the White River Group, Toadstool Geologic Park, Nebraska
Published: 2024-06-14
Subjects: Earth Sciences, Geology, Sedimentology, Stratigraphy
Member of the Brule Formation of the White River Group at Toadstool Geologic Park in Nebraska. Our approach combined descriptive and quantitative methods to reconstruct river flow, sediment transport, channel dynamics, floodplain behavior, and catchment-scale moisture variability and ecosystem function. We found that rivers were ephemeral, with peak flow depths and widths of approximately 2.5 m [...]
A myriad of melt inclusions: a 3D view into the volcanic time capsules of Colli Albani Volcano (Italy)
Published: 2024-06-06
Subjects: Geology, Volcanology
Melt inclusions are small parcels of magma trapped in crystals, which hold key information about pre-eruptive magmatic conditions including volatile content and melt chemistry. We focus here on melt inclusions for a nuanced view of the magmatic pre-eruptive state of Colli Albani, a mafic-alkaline ignimbrite forming system in central Italy. Recent years have seen an increased amount of research [...]
Evolution and architecture of an overbank in an ocean-facing canyon-fill.
Published: 2024-05-21
Subjects: Earth Sciences, Geology, Sedimentology
Submarine canyon-fills comprise substantial volumes of thin-bedded successions deposited by sediment gravity flows that are either stripped or overspill from adjacent channels into highly confined, topographically complex overbank settings. Here, we document the Punta Baja Formation, a rare example of an exhumed canyon-confined overbank succession with good 3D constraints from the Mesozoic [...]
Unconfined turbidity current interactions with oblique slopes: deflection, reflection and combined-flow behaviours
Published: 2024-05-17
Subjects: Geology
What is the nature of flow reflection, deflection and combined-flow behaviour when gravity flows interact with slopes? In turn, how do these flow dynamics control sedimentation on slopes? Here, these questions are addressed using physical experiments, with low-density unconfined gravity flows interacting with slopes of varying gradients, at a range of flow incidence angles. The present paradigm [...]
Bayesian Inversion with TimeOptMCMC
Published: 2024-05-16
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Statistical Methodology, Stratigraphy
TimeOptMCMC (Meyers and Malinverno, 2018) is a Bayesian approach for evaluating cyclostratigraphic records that quantitatively links geologic data with astronomical theory. This manuscript provides an introductory guide for conducting a TimeOptMCMC Bayesian inversion, following the approach of Meyers and Malinverno (2018). The purpose of this guide is to help users identify an appropriate data [...]
Direct observations of transient weakening during phase transformations in quartz and olivine
Published: 2024-05-13
Subjects: Earth Sciences, Geology, Mineral Physics, Tectonics and Structure
Phase transformations are widely invoked as a source of rheological weakening during subduction, continental collision, mantle convection, and various other geodynamic phenomena. However, despite more than half a century of research, the likelihood and magnitude of such weakening in nature remain poorly constrained. Here, we use experiments performed on a synchrotron beamline to reveal transient [...]
The fate of bars in braided rivers
Published: 2024-05-05
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Ancient river deposits are important archives of past landscape conditions on planetary surfaces. On Earth, they host valuable groundwater, energy resources, and carbon-storage potential. Reconstructing details of paleochannel forms and movements refines our understanding of the controls on river behavior under different climate, landcover, and tectonic conditions, and improves predictions and [...]
Interactions between buried mass-transport complexes and subsequent slope failures on a passive margin
Published: 2024-05-03
Subjects: Geology, Geomorphology, Sedimentology
Mass-transport complexes (MTCs) are common features on all continental margins, with stacked MTCs indicating repeated slope failure. This suggests MTC generation and emplacement may pre-condition a slope to fail again, although direct evidence for this is currently lacking. Determining the relationship between MTC development and slope stability is important, given its implications for [...]
The potential of terrestrial and aquatic molluscs for the temporal analysis of Deckenschotter deposits and younger Quaternary sediments from the Swiss Plateau
Published: 2024-05-02
Subjects: Earth Sciences, Geology, Geomorphology, Paleobiology, Paleontology, Physical Sciences and Mathematics, Sedimentology, Soil Science, Stratigraphy, Terrestrial and Aquatic Ecology
Post-collisional reorganisation of the Eastern Alps in 4D: Crust and mantle structure
Published: 2024-04-22
Subjects: Earth Sciences, Geology
The Eastern Alps were affected by a profound post-collisional tectonic reorganisation in Neogene time, featuring indentation by the Adriatic upper plate, rapid uplift and filling of the eastern Molasse Basin, rapid exhumation and eastward orogen-parallel transport of Tertiary metamorphic units in the orogenic core, and a shift from northward thrust propagation in the European plate to southward [...]
Limited long-term cooling effects of flood basalt emplacements
Published: 2024-04-22
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Geology, Volcanology
The emplacement of large igneous provinces (LIPs) is known to have been a driver of climate change in Earth’s past, particularly during the breakup of Pangaea. However, the balance between climate warming through CO2 emission and climate cooling through increased weathering is poorly understood. To better understand the role of LIP emplacement on long-term climate change, we utilize a coupled [...]
GEOTHERMAL ENERGY IN COLOMBIA: GEOLOGICAL FRAMEWORK, EXPLORATION ADVANCES, AND PROSPECTS FOR DEVELOPMENT
Published: 2024-04-16
Subjects: Earth Sciences, Geochemistry, Geology, Geophysics and Seismology, Physical Sciences and Mathematics
This work systematically reviews studies and technical reports on the current state of geothermal energy in Colombia, including its limitations, environmental implications, regulatory progress, and development prospects. Exploration has focused on high-enthalpy volcanic systems (Nevado del Ruiz, Azufral, Paipa, and Tufiño–Chiles–Cerro Negro), where reservoir temperatures exceed 200 °C and [...]
Digitising sandbox experiments using open-source Structure-from-Motion/photogrammetry/Digital Image Correlation package MicMac
Published: 2024-04-15
Subjects: Geology, Geophysics and Seismology, Tectonics and Structure, Volcanology
Structure-from-Motion and photogrammetry have been implemented in sandbox models to monitor deformation of their surface. Various software packages are available, either open-source of commercial. Some commercial packages are intuitive press-button equipment; these can be very practical to use, but they can be very expensive and unaffordable for most academic laboratories. Another option is [...]
Evolution and architecture of an exhumed ocean-facing coarse-grained submarine canyon fill, Baja California, Mexico
Published: 2024-04-15
Subjects: Earth Sciences, Geology, Sedimentology, Stratigraphy, Tectonics and Structure
Present day submarine canyons are active conduits for large volumes of sediment, carbon, and pollutants from continents to oceans. However, the evolution of submarine canyons over geological timescales remains poorly understood due to their erosional nature and low preservation potential. The Late Cretaceous Punta Baja Formation represents a well-preserved submarine canyon-fill on a [...]