Preprints
Filtering by Subject: Earth Sciences
Intensity-Duration-Frequency curves at the global scale
Published: 2018-12-18
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Sciences, Hydraulic Engineering, Hydrology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Water Resource Management
Intensity-Duration-Frequency (IDF) curves usefully quantify extreme precipitation over various durations and return periods for engineering design. Unfortunately, sparse, infrequent or short observations hinder the creation of robust IDF curves in many locations. This paper presents the first global, multi-temporal (1 to 360 hours) dataset of Generalized Extreme Value (GEV) parameters at 31 km [...]
Can we relate the surface expression of dike-induced normal faults to subsurface dike geometry?
Published: 2018-12-14
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
Dikes feed volcanic eruptions and drive crustal extension on Earth and other planetary bodies. Yet many dikes do not reach the surface, instead triggering normal faulting and graben formation in overlying rock. Whilst dike-induced faults provide a surficial and accessible record of active and ancient diking, unlocking these archives is difficult because we do not know how faults grow above or [...]
The Warnie Volcanic Province: A Jurassic Volcanic Province in Central Australia
Published: 2018-12-12
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Stratigraphy, Volcanology
The Cooper and Eromanga Basins of South Australia and Queensland are the largest onshore hydrocarbon 9 producing region in Australia. Igneous rocks have been documented infrequently within end of well reports over 10 the past 34 years, with a late Triassic to Jurassic age determined from well data. However, the areal extent and 11 nature of these basaltic rocks were largely unclear. Here, we [...]
The retreat pattern of glaciers controls the occurrence of turbidity currents on high-latitude fjord deltas
Published: 2018-12-12
Subjects: Earth Sciences, Geology, Geomorphology, Glaciology, Physical Sciences and Mathematics, Sedimentology
Glacier and ice sheet mass loss as a result of climate change is driving important coastal changes in Arctic fjords. Yet, limited information exists for Arctic coasts regarding the influence of glacial erosion and ice mass loss on the occurrence and character of turbidity currents in fjords which themselves affect delta dynamics. Here, we show how glacial erosion and the production of meltwaters [...]
Tracing marine cryptotephras in the North Atlantic during the Last Glacial Period: Improving the North Atlantic marine tephra framework
Published: 2018-12-12
Subjects: Earth Sciences, Other Earth Sciences, Physical Sciences and Mathematics
Tephrochronology is increasingly being recognised as a key tool for the correlation of disparate palaeoclimatic archives, underpinning chronological models and facilitating climatically independent comparisons of climate proxies. Tephra frameworks integrating both distal and proximal tephra occurrences are essential to these investigations providing key information on their spatial distributions, [...]
Tracing marine cryptotephras in the North Atlantic during the Last Glacial Period: Identification, characterisation and depositional controls
Published: 2018-12-12
Subjects: Earth Sciences, Other Earth Sciences, Physical Sciences and Mathematics
Tephrochronology is increasingly being utilised as a key tool for improving chronological models and correlating disparate palaeoclimatic sequences. For many sedimentary environments, however, there is an increased recognition that a range of processes may impart a delay in deposition and/or rework tephra. These processes can affect the integrity of tephra deposits as time-synchronous markers, [...]
Separating the impact of individual land surface properties on the terrestrial surface energy budget in both the coupled and un-coupled land-atmosphere system
Published: 2018-12-12
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Changes in the land surface can drive large responses in the atmosphere on local, regional, and global scales. Surface properties control the partitioning of energy within the surface energy budget to fluxes of shortwave and longwave radiation, sensible and latent heat, and ground heat storage. Changes in surface energy fluxes can impact the atmosphere across scales through changes in [...]
Submarine channels "swept" downstream after bend cutoff in salt basins
Published: 2018-12-08
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Channel-bend expansion and downstream translation, as well as vertical movements by aggradation and incision, set the stratigraphic architecture of channelized depositional systems. Early work on submarine-channel evolution has suggested that downstream translation is rare. We propose that downstream translation of bends might be common in deep-water salt-tectonic provinces, where complex [...]
No evidence for sea level fall in the Cretaceous strata of the Book Cliffs of Eastern Utah
Published: 2018-12-08
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
A core component of the sequence stratigraphic model is the implicit assumption of a semi-sinusoidal relative sea-level curve, and the occurrence of “sequence boundaries” formed during intervals of sea-level fall, recognized primarily by the presence of incised valleys. Late Cretaceous paralic deposits in the Book Cliffs, Utah, have been one of the main testing and teaching grounds for [...]
Tectonic controls on deposition in the late Cambrian - Early Ordovician Central Andean Basin (Cordillera Oriental; northwest Argentina) – the first step towards an integrative reconstruction
Published: 2018-12-07
Subjects: Earth Sciences, Geology, Paleontology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
This study focuses on upper Cambrian – Lower Ordovician strata containing the lowermost fossil-bearing levels of the basin (Santa Rosita Formation and Guayoc Chico Group). Bounded by two major regional unconformities, this stratigraphic interval was previously considered as a retro-arc foreland basin displaying evidence of westward progradation without tectonic activity during its deposition. [...]
Toward a unified approach to quantify uncertainties in sea-level projections
Published: 2018-12-07
Subjects: Earth Sciences, Other Earth Sciences, Physical Sciences and Mathematics
Coastal impacts of climate change and the related mitigation and adaptation needs requires assessments of future sea-level changes. Following a common practice in coastal engineering, probabilistic sea-level projections have been proposed for at least 20 years. This requires a probability model to represent the uncertainties of future sea-level rise, which is not achievable because potential ice [...]
Early Last Interglacial ocean warming drove substantial ice mass loss from Antarctica
Published: 2018-12-06
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
The future response of the Antarctic ice sheets to rising temperatures remains highly uncertain. A valuable analogue for assessing the sensitivity of Antarctica to warming is the Last Interglacial (129-116 kyr), when global sea level peaked 6 to 9 meters above present. Here we report a blue-ice record of ice-sheet and environmental change from the periphery of the marine-based West Antarctic Ice [...]
Critical Review of Polyphosphate and Polyphosphate Accumulating Organisms for Agricultural Water Quality Management
Published: 2018-12-03
Subjects: Agriculture, Biogeochemistry, Earth Sciences, Environmental Microbiology and Microbial Ecology Life Sciences, Environmental Sciences, Life Sciences, Microbiology, Natural Resources Management and Policy, Physical Sciences and Mathematics, Soil Science, Water Resource Management
Despite ongoing management efforts, phosphorus (P) loading from agricultural landscapes continues to impair water quality. Wastewater treatment research has enhanced our knowledge of microbial mechanisms influencing P cycling, especially regarding microbes known as polyphosphate accumulating organisms (PAOs) that store P as polyphosphate (polyP) under oxic conditions and release P under anoxic [...]
Episodic fluid flow in an active fault
Published: 2018-11-30
Subjects: Earth Sciences, Geology, Hydrology, Physical Sciences and Mathematics, Tectonics and Structure
We present a 250 ka record of episodic fluid flow along the Malpais fault which hosts the Beowawe hydrothermal system, Nevada, USA. The history of fluid flow was quantified using a novel combination of the apatite (U-Th)/He (AHe) thermochronometer and a model of the thermal effects of fluid flow. Samples show partial resetting of the AHe thermochronometer in a 40 m wide zone around the normal [...]
Evolving marginal terranes during Neoproterozoic supercontinent reorganisation: constraints from the Bemarivo Domain in northern Madagascar
Published: 2018-11-29
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Madagascar is important for unravelling the geodynamic evolution of the transition between the Rodinia and Gondwana supercontinents as it contains several suites of c. 850–700 Ma magmatic rocks that have been postulated to correlate with other ex-Rodinia terranes. The Bemarivo Belt of northern Madagascar contains the youngest suite of these magmatic rocks that date to c. 750–700 Ma. We present [...]