Filtering by Subject: Earth Sciences
Published: 2021-02-26
Subjects: Earth Sciences, Geology, Paleobiology, Paleontology, Sedimentology, Stratigraphy
Stratigraphic changes in the clustering of first or last taxon occurrences are a joint expression of evolutionary, ecological, taphonomic, and sedimentological processes. Sedimentation rates control the degree of sedimentary dilution and condensation and thus alter the time contained in a given thickness of sediment. However, it remains poorly explored quantitatively how distinct the [...]
Published: 2021-02-25
Subjects: Earth Sciences, Geophysics and Seismology
The equivalent source technique is a powerful and widely used method for processing gravity and magnetic data. Nevertheless, its major drawback is the large computational cost in terms of processing time and computer memory. We present two techniques for reducing the computational cost of equivalent source processing: block-averaging source locations and the gradient-boosted equivalent source [...]
Published: 2021-02-25
Subjects: Climate, Earth Sciences, Geology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Paleontology, Sedimentology, Stratigraphy
This study proposes that sandstone layers exposed in the Fez-Meknes region of Northern Morocco (Ben Allou (Sidi Chaded) and El Adergha localities), have been misinterpreted as unique examples of geostrophically-driven, deep marine (150 - 400 m water depth) sandy contourites. Instead, our independent paleontological, sedimentological, and stratigraphic analyses show that these sandstones represent [...]
Published: 2021-02-24
Subjects: Chemistry, Earth Sciences, Physical Sciences and Mathematics
Patawarta Diapir, located in the Central Flinders Ranges, South Australia, has been interpreted as a single allochthonous salt sheet containing Tonian-aged igneous and layered evaporite sedimentary intrasalt inclusions derived from the Callanna Group. Using detailed field mapping, petrographic analysis, and lithostratigraphic correlation within Patawarta Diapir, five primarily silty limestone [...]
Published: 2021-02-24
Subjects: Earth Sciences, Geochemistry, Geology, Tectonics and Structure
Forearc basins preserve the geologic record relating strictly to arc magmatism. The provenance of forearc sediment can be used to differentiate periods of crustal growth, accretion, and destruction, enhanced magmatism, advancing and retreating subduction slabs, delamination, etc. All these tectonic events systems predict differing degrees of sedimentary reworking of the older forearc units. [...]
Published: 2021-02-24
Subjects: Civil and Environmental Engineering, Construction Engineering and Management, Earth Sciences, Engineering, Environmental Engineering, Environmental Health and Protection, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Sustainability, Water Resource Management
Heat-related mortality and flooding are pressing challenges for the >4 billion urban population worldwide, exacerbated by increasing urbanization and climate change. Urban greening, such as green roofs and parks, can potentially help address both problems, but the geographical variation of the relative hydrological and thermal performance benefits of such interventions are unknown. Here we [...]
Published: 2021-02-23
Subjects: Earth Sciences, Geology, Tectonics and Structure
The formation of a global network of plate boundaries surrounding a mosaic of lithospheric fragments was a key step in the emergence of Earth’s plate tectonics. So far, propositions for plate boundary formation are regional in nature but how plate boundaries are being created over 1000s of km in short periods of geological time remains elusive. Here, we show from geological observations that a [...]
Published: 2021-02-22
Subjects: Earth Sciences, Geology
Submarine landslides are major geohazards occurring on distinct seabed domains ranging from shallow coastal areas to the deeper points of the ocean. The nature and relief of the seabed are key factors influencing the location and size of submarine landslides. Efforts have recently been made to compile databases of submarine landslide distribution and morphometry, a crucial task to assess [...]
Published: 2021-02-19
Subjects: Earth Sciences, Education, Environmental Sciences, Geology, Higher Education, Outdoor Education, Science and Mathematics Education
Fieldwork is considered critical to developing technical skills in geoscience education, and typical undergraduate degrees require >30 days in the field. Tuition costs of enrolling in field camp are acknowledged as a barrier to participation in geosciences; however, the cost of participation in field activities may also include the cost of personal field gear (hiking boots, backpacks, etc.), [...]
Published: 2021-02-18
Subjects: Earth Sciences, Geochemistry, Other Earth Sciences, Physical Sciences and Mathematics, Volcanology
The flow of high-temperature and compositionally-enriched material between mantle plumes and nearby spreading centres influences up to 30% of the global mid-ocean ridge system and represents a significant, but currently unconstrained, flux of volatiles out of the mantle. Here we present new analyses of H2O, F, Cl and S in basaltic glass chips from an archetypal region of plume-ridge interaction, [...]
Published: 2021-02-14
Subjects: Earth Sciences, Geology, Geomorphology, Sedimentology, Stratigraphy, Tectonics and Structure
The area of the Offshore NW Sulawesi lies between eastern Sundaland (Borneo) and the North Arm of Sulawesi. Possible influences on the basins include Paleogene rifting in the Celebes Sea and Makassar Strait, Neogene subsidence and uplift in Borneo, late Neogene subduction at the present-day North Sulawesi Trench, and displacements related to the Palu-Koro Fault. This study presents the results of [...]
Published: 2021-02-14
Subjects: Civil and Environmental Engineering, Computer Sciences, Earth Sciences, Engineering, Environmental Engineering, Environmental Sciences, Geology, Geomorphology, Glaciology, Hydrology, Numerical Analysis and Scientific Computing, Other Environmental Sciences, Physical Sciences and Mathematics, Sedimentology, Soil Science, Stratigraphy
Computational modelling occupies a unique niche in Earth environmental sciences. Models serve not just as scientific technology and infrastructure, but also as digital containers of the scientific community's understanding of the natural world. As this understanding improves, so too must the associated software. This dual nature---models as both infrastructure and hypotheses---means that [...]
Published: 2021-02-13
Subjects: Earth Sciences
Subsurface salt flow can deform overlying strata and influence contemporaneous sedimentary processes. Studying salt-sediment interactions is challenging in the subsurface due to poor imaging adjacent to salt, and in the field due to the dissolution of halite. Discrete Element Modelling provides an efficient and inexpensive tool to model stratigraphy and deformation around salt structures, which [...]
Published: 2021-02-11
Subjects: Earth Sciences
The use of wood, dung and other biomass fuels can be traced back to early prehistory. Whilst the study of prehistoric fuel use and its environmental impacts is well established, there has been little investigation of the health impacts this would have had, particularly in the Neolithic period, when people went from living in relatively small groups, to living in dense settlements. The UNESCO [...]
Published: 2021-02-10
Subjects: Earth Sciences
Although infrequent, large earthquakes (Mw8+) can be extremely damaging and occur on subduction and intraplate faults worldwide. Earthquake early warning (EEW) systems aim to provide advanced warning before strong shaking and tsunami onsets. These models estimate earthquake magnitude by the early metrics of waveforms, relying on empirical scaling relationships of abundant past events. However, [...]