Preprints
Filtering by Subject: Earth Sciences
Can hydrocarbon extraction from the crust enhance or inhibit seismicity in tectonically active regions? A statistical study in Italy
Published: 2021-03-17
Subjects: Earth Sciences, Environmental Sciences, Statistics and Probability
A number of oil- and gas-producing leases have been operating in Italy in the last decades, many of which are located in the surroundings of tectonically active regions. Identifying human-induced seismicity in areas with high levels of natural seismicity is a difficult task for which virtually any result can be a source of controversy. We implemented a large-scale analysis aiming at tracking [...]
Multi-scale and multi-parametric analysis of Late Quaternary event deposits within the active Corinth Rift (Greece)
Published: 2021-03-17
Subjects: Earth Sciences
A major challenge in subaqueous paleoseismology is to understand the relationship between an earthquake/tsunami and a sedimentary event deposit recorded in drillcores. Expedition 381 of the International Ocean Discovery Program was dedicated to understanding the development of the Corinth Rift, Greece. Its drilled cores provide a potentially important resource to better understand depositional [...]
Silurian carbonate high-energy deposits of potential tsunami origin: distinguishing lateral redeposition and time averaging using carbon isotope chemostratigraphy
Published: 2021-03-17
Subjects: Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy
Stable carbon isotope curves are used as a precise stratigraphic tool in the Paleozoic, even though they are commonly based on shallow-water carbonate record, characterized by low stratigraphic completeness. Identification of episodes of large-scale redeposition and erosion may improve δ13Ccarb-based correlations. Here, a series of at least three episodes of high-energy onshore redeposition are [...]
The Sidi Ifni transect across the rifted margin of Morocco (Central Atlantic): Vertical movements constrained by low-temperature thermochronology
Published: 2021-03-17
Subjects: Earth Sciences, Geology, Geomorphology, Paleontology, Sedimentology, Stratigraphy, Tectonics and Structure
The occurrence of km-scale exhumations during syn- and post-rift stages has been documented along Atlantic continental margins, which are also characterised by basins undergoing substantial subsidence. The relationship between the exhuming and subsiding domains is poorly understood. In this study, we reconstruct the evolution of a 50 km long transect across the Moroccan rifted margin from the [...]
Lithologic Controls on Silicate Weathering Regimes of Temperate Planets
Published: 2021-03-12
Subjects: Astrophysics and Astronomy, Earth Sciences, Geochemistry, Planetary Geochemistry, Planetary Sciences
Weathering of silicate rocks at a planetary surface can draw down CO2 from the atmosphere for eventual burial and long-term storage in the planetary interior. This process is thought to provide essential negative feedback to the carbonate-silicate cycle (carbon cycle) to maintain clement climates on Earth and potentially similar temperate exoplanets. We implement thermodynamics to determine [...]
Large-scale natural fracture network patterns: Insights from automated mapping in the Lilstock (Bristol Channel) limestone outcrops
Published: 2021-03-12
Subjects: Earth Sciences
The Lilstock outcrop in the southern Bristol Channel provides exceptional outcrop of several limestone layers with stratabound fracture networks, providing the opportunity to create a very large, complete, and ground-truthed fracture model. Here we present the result of automated fracture extraction of high-resolution photogrammetric images (0.9 cm/pixel) of the full outcrop, obtained using an [...]
Phosphorus supply affects long-term carbon accumulation in mid-latitude ombrotrophic peatlands
Published: 2021-03-12
Subjects: Earth Sciences, Environmental Sciences
Ombrotrophic peatlands are a globally important carbon store and depend on atmospheric nutrient deposition to balance ecosystem productivity and microbial decomposition. Human activities have increased atmospheric nutrient fluxes, but the impacts of variability in phosphorus supply on carbon sequestration in ombrotrophic peatlands are unclear. Here, we synthesise phosphorus, nitrogen and carbon [...]
The Ca and Mg isotope record of the Cryogenian Trezona carbon isotope excursion
Published: 2021-03-11
Subjects: Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy
The Trezona carbon isotope excursion is recorded on five different continents in platform carbonates deposited prior to the end-Cryogenian Marinoan glaciation (>635 Ma) and represents a change in carbon isotope values of 16-18 per mill. Based on the spatial and temporal reproducibility, the excursion previously has been interpreted as tracking the carbon isotopic composition of dissolved [...]
The imprint of erosion by glacial lake outburst floods in the topography of central Himalayan rivers
Published: 2021-03-11
Subjects: Earth Sciences, Geomorphology
In steep landscapes, river incision sets the pace of landscape evolution. Transport of coarse sediment controls incision by evacuating material delivered to river channels by landslides. However, large landslide-derived boulders that impede bedrock erosion are immobile even in major runoff-driven floods. Glacial lake outburst floods (GLOFs) mobilize these boulders and drive incision, yet their [...]
Local and global controls on carbon isotope chemostratigraphy
Published: 2021-03-11
Subjects: Earth Sciences
Over million-year timescales, the geologic cycling of carbon controls long-term climate and the oxidation of Earth's surface. Inferences about the carbon cycle can be made from time series of carbon isotopic ratios measured from sedimentary rocks. The foundational assumption for carbon isotope chemostratigraphy is that carbon isotope values reflect dissolved inorganic carbon in a well-mixed ocean [...]
Climate change risks to push one-third of global food production outside Safe Climatic Space
Published: 2021-03-09
Subjects: Agriculture, Earth Sciences, Environmental Sciences
Climate change will alter key climatic conditions which human societies directly rely on and which, for example, food production is adjusted to. Here, using Holdridge Life Zones, we define Safe Climatic Space (SCS), a concept that incorporates the decisive climatic characteristics of precipitation, temperature and aridity. This allows us first to define the climatic niche of current food [...]
Recrystallization of ice enhances the creep and vulnerability to fracture of ice shelves
Published: 2021-03-08
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics
The initiation of fractures and fast flow in floating regions of Antarctica have the potential to destabilize large regions of the grounded ice sheet, leading to significant sea-level rise. While observations have shown rapid, localized deformation and damage in the margins of fast-flowing glaciers, there remain gaps in our understanding of how rapid deformation affects the viscosity and [...]
New insight into post-seismic landslide evolution processes in the tropics
Published: 2021-03-05
Subjects: Earth Sciences, Geomorphology, Geophysics and Seismology, Hydrology
Earthquakes do not only trigger landslides in co-seismic phases but also elevate post-seismic landslide susceptibility either by causing a strength reduction in hillslope materials or by producing co-seismic landslide deposits, which are prone to further remobilization under the external forces generated by subsequent rainfall events. However, we still have limited observations regarding the [...]
Crisis at the Salton Sea: The Vital Role of Science
Published: 2021-03-04
Subjects: Atmospheric Sciences, Biogeochemistry, Chemistry, Climate, Earth Sciences, Environmental Chemistry, Environmental Public Health, Environmental Sciences, Environmental Studies, Geochemistry, Geology, Geomorphology, Hydrology, Medicine and Health Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Public Health, Social and Behavioral Sciences
The Salton Sea—a hypersaline, terminal lake in southern California—is in crisis. A combination of mismanagement and competition among federal, state and local agencies has hindered efforts to address declining lake levels and unstable water chemistry. This delay has heightened the public health threat to regional communities as retreating shorelines expose dry lakebed— a source of potentially [...]
Use of machine learning to estimate statistics of the posterior distribution in probabilistic inverse problems - an application to airborne EM data.
Published: 2021-03-03
Subjects: Earth Sciences, Physical Sciences and Mathematics
The solution to a probabilistic inverse problem is the posterior probability distribution for which a full analytic expression is rarely possible. Sampling methods are therefore often used to generate a sample from the posterior. Decision-makers may be interested in the probability of features related to model parameters (for example existence of a pollution or the cumulative clay thickness) [...]