Preprints
Filtering by Subject: Physical Sciences and Mathematics
Representative elementary volumes, hysteresis and heterogeneity in multiphase flow from the pore to continuum scale
Published: 2019-09-22
Subjects: Earth Sciences, Engineering, Hydrology, Physical Sciences and Mathematics
Representative elementary volumes (REVs) and heterogeneity are key concepts in continuum multiphase flow, yet their manifestation from the pore-scale and associated impacts with the flow regime are not well understood. We use a multi-scale experimental and modelling approach to elucidate the role of REVs, hysteresis and heterogeneity in multiphase flow in two distinct water-wetting Bentheimer [...]
The Community Code Verification Exercise for Simulating Sequences of Earthquakes and Aseismic Slip (SEAS)
Published: 2019-09-22
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Numerical simulations of Sequences of Earthquakes and Aseismic Slip (SEAS) have made great progress over the past decades to address important questions in earthquake physics and fault mechanics. However, significant challenges in SEAS modeling remain in resolving multiscale interactions between aseismic fault slip, earthquake nucleation, and dynamic rupture; and understanding physical factors [...]
An image- and BET-based Monte-Carlo approach to determine mineral accessible surface areas in sandstones
Published: 2019-09-22
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
Accessible surface areas (ASAs) of individual rock-forming minerals exert a fundamental control on how minerals react with formation fluids. However, due to lacking adequate quantification methods, determining the ASAs of specific minerals in a multi-mineral rock at the appropriate scale still remains difficult. Whole-rock Brunauer-Emmett-Teller (BET) measurements at atomic scales cannot account [...]
Controls on the development and termination of failed continental rifts: Insights from the crustal structure and rifting style of the North Sea via ambient noise tomography
Published: 2019-09-22
Subjects: Applied Mathematics, Computer Sciences, Earth Sciences, Geophysics and Seismology, Numerical Analysis and Computation, Numerical Analysis and Scientific Computing, Physical Sciences and Mathematics, Probability, Statistics and Probability
The mid to lower crust plays an important role in rift initiation and evolution, particularly when large scale sutures and/or terrane boundaries are present. These inherited features can focus strain or act as inhibitors to extensional deformation. Ancient tectonic features are known to exist beneath the iconic failed rift system of the North Sea making it the ideal location to investigate the [...]
Dislocation interactions during low-temperature plasticity of olivine strengthen the lithospheric mantle
Published: 2019-09-21
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
The strength of the lithosphere is typically modelled based on constitutive equations for steady-state flow. However, models of lithospheric flexure reveal differences in lithospheric strength that are difficult to reconcile based on such flow laws. Recent rheological data from low-temperature deformation experiments on olivine suggest that this discrepancy may be largely explained by strain [...]
NSB: an expanded and improved database of marine planktonic microfossil data and deep-sea stratigraphy
Published: 2019-09-19
Subjects: Computer Sciences, Databases and Information Systems, Earth Sciences, Paleontology, Physical Sciences and Mathematics, Stratigraphy
Thirty years ago, the Neptune Database was created to synthesize microfossil occurrences from the deep-sea drilling record. It has been used in numerous studies by both biologists and paleontologists of the evolution and distribution in space and time of marine microplankton. After decades of discontinuous development in various institutions, a significant overhaul of the system was made during [...]
Skillful seasonal prediction of key carbon cycle components: NPP and fire risk
Published: 2019-09-19
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Seasonal forecasts of global CO₂ concentrations rely on the well-documented relationship with the El Niño–Southern Oscillation (ENSO), combined with estimated anthropogenic emissions. Here, we investigate the skill of the GloSea5 seasonal forecasting system for two carbon cycle processes that underlie the global CO₂–ENSO relationship: the impact of meteorological conditions on CO₂ uptake by [...]
Global groundwater sustainability, resources and systems in the Anthropocene
Published: 2019-09-19
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Groundwater is a crucial resource for current and future generations but is not being sustainably used in many parts of the world. The objective of this review is to provide a clear portrait of global-scale groundwater sustainability, systems and resources in the Anthropocene, in order to inspire a pivot towards more sustainable pathways. We examine groundwater from three different but related [...]
Wide-swath altimetric satellite data assimilation with structured-error detrending
Published: 2019-09-18
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
For decades now, satellite altimetric observations have been successfully integrated in numerical oceanographic models using data assimilation (DA). So far, sea surface height (SSH) data were provided by one-dimensional nadir altimeters. The next generation Surface Water and Ocean Topography (SWOT) satellite altimeter will provide two-dimensional wide-swath altimetric information with an [...]
The influence of local low-density basement anomalies on the distribution of fluvio-deltaic sediment in rift basins: the early Carboniferous Fell Sandstone Formation, northern England
Published: 2019-09-18
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Tectonics and Structure
Local low-density basement anomalies are an important part of a rift basin’s inherited structural framework that can influence basin stratigraphy. Large granitic intrusions can cause local alterations in the basement’s density and often spatially correlate with fault-bounded highs (blocks) or convex-shaped regional flexural highs due to their isostatic responses. We investigate the influence of [...]
Weak phases production and heat generation controls fault friction during seismic slip
Published: 2019-09-15
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The triggering and magnitude of earthquakes is determined by the friction evolution along faults. Experimental results have revealed a drastic decrease of the friction coefficient for velocities close to the maximum seismic one, independently of the material studied. Due to the extreme loading conditions during seismic slip, many competing physical phenomena are occurring (like mineral [...]
Miniature paleo-speleothems from the earliest Ediacaran (635 Ma) Doushantuo cap dolostone in South China and their implications for terrestrial ecosystems
Published: 2019-09-15
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Speleology, Stratigraphy
Speleothems can offer insights into terrestrial life because their formation is critically dependent on soil-microbial ecosystems. Here we report the wide distribution of miniature paleo-speleothems from the ~635 Ma Doushantuo cap dolostone in South China in order to understand the recovery of terrestrial life after the terminal Cryogenian Marinoan snowball Earth glaciation. The cap dolostone was [...]
Infilling abandoned deltaic channels through tidal sedimentation: a case study from the Huanghe (Yellow River) delta, China
Published: 2019-09-12
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Upon avulsion, abandoned deltaic distributary channels receives water and sediment delivered by a tie channel, overbank flow, and by tidal inundation from the receiving basin. The transport and deposition of sediment arising from this latter input have important impacts on delta development, yet are not well-constrained from field observations or numerical models. Herein, the Huanghe (Yellow [...]
Coseismic or Landslide? The source of the 2018 Palu Tsunami
Published: 2019-09-11
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
On 28 September, 2018, Indonesia was struck by a MW 7.5 strike-slip earthquake. An unexpected tsunami followed, inundating nearby coastlines leading to extensive damage. Given the traditionally non-tsunamigenic mechanism, it is important to ascertain if the source of the tsunami is indeed from coseismic deformation, or something else, such as shaking induced landsliding. Here we determine the [...]
A report on gender diversity and equality at Tectonic Studies Group (TSG) meetings: 2007-2019.
Published: 2019-09-10
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
The Tectonic Studies Group (TSG) is a specialist group of the Geological Society of London that was founded in 1970 as a forum for discussion of research in structural geology and tectonics. Here, we report on gender diversity and equality at the TSG annual conferences between 2007 and 2019. Gender diversity was analysed in the following categories: 1.) talks presented; 2.) posters presented; 3.) [...]