Preprints
There are 4725 Preprints listed.
A Persistent Non-uniformitarian Paleomagnetic Field in the Devonian?
Published: 2021-05-13
Subjects: Physical Sciences and Mathematics
The Devonian, like much of the Paleozoic, has long been a problematic period for paleomagnetism. Devonian paleomagnetic data are generally difficult to interpret and have complex partial or full overprints; problems that arise in data obtained from both sedimentary and igneous rocks. As a result, the reconstruction of tectonic plate motions, performed largely using apparent polar wander paths, [...]
The influence of rock uplift rate on the formation and preservation of individual marine terraces during multiple sea level stands
Published: 2021-05-13
Subjects: Climate, Geology, Geomorphology
Marine terraces are a cornerstone for the study of paleo sea level and crustal deformation. Commonly, individual erosive marine terraces are attributed to unique sea level high-stands. This stems from early reasoning that erosive marine platforms could only be significantly widened at the beginning of an interglacial. However, this implies that wave erosion is insignificant during the vast [...]
Multiple imputation via chained equations for elastic well log imputation and prediction
Published: 2021-05-13
Subjects: Geophysics and Seismology
Well logging is an essential component in the petroleum industry for developing a proper understanding of the subsurface geology and formation conditions. Unfortunately, the measurements are rarely complete and missing data intervals are common due to operational issues or malfunction of the logging device. Therefore the imputation of missing data from down-hole well logs is a common problem in [...]
Primordial and recycled sulfur sampled by the Iceland mantle plume
Published: 2021-05-13
Subjects: Earth Sciences, Geochemistry
Stable sulfur isotope ratios of mid-ocean ridge and ocean island basalts (MORBs and OIBs) preserve unique information about early Earth processes and the long-term volatile cycles between Earth’s mantle and the surface. Icelandic basalts present ideal material to examine the oldest known terrestrial mantle reservoir, accessed through a deep-rooted mantle plume, but their multiple sulfur [...]
Structural Inheritance Controls Strain Distribution During Early Continental Rifting, Rukwa Rift
Published: 2021-05-13
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Little is known about rift kinematics and strain distribution during the earliest phase of extension due to the deep burial of the pre-rift and earliest rift structures beneath younger, rift-related deposits. Yet, this exact phase of basin development ultimately sets the stage for the location of continental plate divergence and breakup. Here, we investigate the structure and strain distribution [...]
A re-examination of the mechanism of whiting events: A new role for diatoms in Fayetteville Green Lake (New York, USA)
Published: 2021-05-08
Subjects: Biogeochemistry, Environmental Microbiology and Microbial Ecology Life Sciences, Geochemistry, Life Sciences, Sedimentology
Whiting events – the episodic precipitation of fine-grained suspended calcium cabonates in the water column – have been documented across a variety of marine and lacustrine environments. Whitings likely are a major source of carbonate muds, a constituent of limestones, and important archives for geochemical proxies of Earth history. While several biological and physical mechanisms have been [...]
What you net depends on if you grab: A meta-analysis of sampling method's impact on measured aquatic microplastic concentration
Published: 2021-05-08
Subjects: Design of Experiments and Sample Surveys, Environmental Monitoring, Fresh Water Studies, Hydrology, Other Environmental Sciences
Microplastic pollution is measured with a variety of sampling methods. Field experiments indicate that commonly used sampling methods, including net, pump and grab samples, do not always result in equivalent measured concentration. We investigate the comparability of these methods through a meta-analysis of over one hundred surface water microplastic studies. We find systematic relationships [...]
Advancing river corridor science beyond disciplinary boundaries with an inductive approach to catalyse hypothesis generation
Published: 2021-05-08
Subjects: Hydrology
A unified conceptual framework for river corridors requires synthesis of diverse site-, method- and discipline-specific findings. The river research community has developed a substantial body of observations and process-specific interpretations, but we are still lacking a comprehensive model to distill this knowledge into fundamental transferable concepts. We confront the challenge of how a [...]
Thermo-Chemical Dynamics in Earth's Core Arising from Interactions with the Mantle
Published: 2021-05-08
Subjects: Physical Sciences and Mathematics
Thermo-chemical interactions at the core-mantle boundary (CMB) play an integral role in determining the dynamics and evolution Earth's deep interior. This review considers the processes in the core that arise from heat and mass transfer at the CMB, with particular focus on thermo-chemical stratification and the precipitation of oxides. A fundamental parameter is the thermal conductivity of the [...]
The influence of crustal strength on rift geometry and development – Insights from 3D numerical modelling
Published: 2021-05-07
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
The lateral distribution of strength within the crust is non-uniform, dictated by crustal lithology and the presence and distribution of heterogeneities within it. During continental extension, areas of crust with distinct lithological and rheological properties manifest strain differently, influencing the structural style, geometry and evolution of the developing rift system. Here, we use 3D [...]
On the Land Emissivity Assumption and Landsat-Derived Surface Urban Heat Islands: A Global Analysis
Published: 2021-05-07
Subjects: Physical Sciences and Mathematics
The prescription of surface emissivity (ε) strongly controls satellite-derived estimates of land surface temperature (LST). This is particularly important for studying surface urban heat islands (SUHI) since built-up and natural landscapes are known to have distinct ε values. Given the small signal associated with the SUHI compared to LST, accurately prescribing urban and rural ε would improve [...]
Fracture distribution in a folded fluvial succession: the Puig-reig anticline (South-eastern Pyrenees)
Published: 2021-05-07
Subjects: Geology, Sedimentology, Stratigraphy, Tectonics and Structure
Sedimentary rocks of foreland fold-and-thrust belts typically undergo intensive fracturing as fold grows. The resulting fracture networks can present significant variations depending on the distribution of sedimentary facies and the complex structural characteristics of fold-and-thrust belts. The Puig-reig anticline, located in the south-eastern Pyrenees, mainly exposes proximal fluvial deposits [...]
Global Assessment of Oil and Gas Methane Ultra-Emitters
Published: 2021-05-07
Subjects: Atmospheric Sciences, Oil, Gas, and Energy
Methane emissions from oil and gas (O&G) production and transmission represent a significant contribution to climate change. These emissions comprise sporadic releases of large amounts of methane during maintenance operations or equipment failures not accounted for in current inventory estimates. We collected and analyzed hundreds of very large releases from atmospheric methane images sampled [...]
Hydroclimatic Analysis of Rising Water Levels in the Great Rift Valley Lakes of Kenya
Published: 2021-05-05
Subjects: Engineering, Physical Sciences and Mathematics
Study Region The Great Rift Valley lakes of Kenya have recently experienced significant increases in their water levels, negatively impacting the local communities. This has provoked renewed concerns about the causations, with various geological, anthropogenic and hydro-climatic influences hypothesized as potential causes of the water level rises. Study Focus This study analyses and documents [...]
The gap between atmospheric nitrogen deposition experiments and reality
Published: 2021-05-05
Subjects: Agricultural Science, Agriculture, Atmospheric Sciences, Biogeochemistry, Environmental Indicators and Impact Assessment, Environmental Microbiology and Microbial Ecology Life Sciences, Environmental Monitoring, Forest Biology, Other Environmental Sciences, Planetary Biogeochemistry, Soil Science, Terrestrial and Aquatic Ecology
Anthropogenic activities have dramatically altered the global nitrogen (N) cycle. Atmospheric N deposition, primarily from combustion of biomass and fossil fuels, has caused acidification of precipitation and freshwater and triggered intense research into ecosystem responses to this pollutant. Experimental simulations of N deposition have been the main scientific tool to understand ecosystem [...]