Preprints
Filtering by Subject: Earth Sciences
Are marl-limestone alternations mainly driven by CaCO3 variations at the astronomical timescale? New insights from extraterrestrial 3He
Published: 2023-01-07
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy
Marl-limestone alternations are rhythmical inter-bedded deposits that commonly occur in many sedimentological environments. It is quite well established that these lithological variations originate from astronomically-driven climatic variations paced by the Milankovitch cycles of main periods 19, 23, 41, 100 and 405 ka. However, the sedimentological mechanisms involved are not clear: some models [...]
Assessing automated gap imputation of regional scale groundwater level data sets with typical gap patterns
Published: 2023-01-04
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Large groundwater level (GWL) data sets are often patchy with hydrographs containing continuous gaps and irregular measurement frequencies. However, most statistical time series analyses require regular observations, thus hydrographs with larger gaps are routinely excluded from further analysis despite the loss of coverage and representativity of an initially large data set. Missing values can be [...]
Analysis of nationwide groundwater monitoring networks using lumped-parameter models
Published: 2022-12-29
Subjects: Earth Sciences, Environmental Sciences, Other Civil and Environmental Engineering
Many countries maintain nationwide groundwater networks to monitor the status of their groundwater resources. For effective groundwater resource management, it is fundamental to understand the groundwater dynamics measured in the individual monitoring wells. Nationwide monitoring networks typically cover multiple aquifer systems with different degrees of environmental complexity. The analysis of [...]
Two sources of uncertainty in estimating tephra volumes from isopachs: perspectives and quantification
Published: 2022-12-27
Subjects: Earth Sciences
Calculating the volume of tephra erupted is important for estimating eruption intensity and magnitude. Traditionally, tephra volumes are estimated by integrating the area under curves fit to the square root of hand-drawn isopach areas. Previous studies have attempted to quantify the uncertainty in this approach, but not all sources of uncertainty have been well-analyzed or addressed. In this [...]
Uncertainties in Water Scarcity Index due to water use and climate changes: Case of two Legal Amazon watersheds
Published: 2022-12-23
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics, Sustainability, Water Resource Management
Water scarcity is a major global problem with the potential to impact socioeconomic development and the environment. Currently, mitigating issues related to the lack of water has become an aim for the public and private sectors. Water scarcity can be estimated by the ratio between water use (withdrawal or consumption) and water availability (a minimum discharge), named Water Stress Index (WSI). [...]
Return of the Atacama deep Slow Slip Event : the 5-year recurrence confirmed by continuous GPS
Published: 2022-12-19
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Four years ago, using survey GPS measurements, the first deep slow slip event (SSE) was detected in Chile (near Copiapó, Atacama region), unrelated to any major earthquake. It was located between 40 and 60 km depth on the subduction interface, lasted approximately 18 months (2014-2016.5) and reached an equivalent magnitude of Mw~6.9. The single permanent station operating in the region between [...]
Role of fluid on earthquake occurrence: Example of the 2019 Ridgecrest and the 1997, 2009 and 2016 Central Apennines sequences
Published: 2022-12-19
Subjects: Earth Sciences
This paper focuses on the study of the temporal evolution of seismicity and the role of fluids during major earthquake sequences that occurred in the central Apennines and Southern Walker Lane belt-Eastern California Shear Zone over the last two decades: The 1997 Colfiorito sequence, the 2009 L’Aquila sequence, the 2016 Amatrice-Norcia sequence, and the 2019 Ridgecrest sequence. The availability [...]
Evolution of the seasonal dynamics of the lake-terminating glacier Fjallsjökull, southeast Iceland, inferred using high-resolution repeat UAV imagery
Published: 2022-12-16
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Proglacial lakes are becoming ubiquitous at the termini of many glaciers worldwide, leading to increased glacier mass loss and terminus retreat, yet an understanding of the key processes forcing their behaviour is lacking. This study utilised high-resolution repeat uncrewed aerial vehicle (UAV)-Structure from Motion (SfM) imagery to provide insights into the changing dynamics of Fjallsjökull, a [...]
Stinging News: ‘Dickinsonia’ discovered in the Upper Vindhyan of India Not Worth the Buzz
Published: 2022-12-16
Subjects: Earth Sciences, Physical Sciences and Mathematics
A recent report of Dickinsonia tenuis ‘hiding in plain sight’ at the Bhimbetka rock shelters in rocks of the Maihar sandstone (Upper Vindhyan) has important implications for paleogeography and the age of the Upper Vindhyan. We visited the site in December 2022 and found the evidence for Dickisonia lacking. The ‘fossil’ resembles decayed parts of modern Apis dorsata (giant honeybees) hives. In [...]
Barometers behaving badly II: A critical evaluation of Cpx-only and Cpx-Liq thermobarometry in variably-hydrous arc magmas
Published: 2022-12-14
Subjects: Earth Sciences, Geochemistry, Geology, Volcanology
The chemistry of erupted clinopyroxene crystals (±equilibrium liquids) have been widely used to deduce the pressures and temperatures of magma storage in volcanic arcs. However, the large number of different equations parametrizing the relationship between mineral and melt compositions and intensive variables such as pressure and temperature yield vastly different results, with [...]
Transgressive rocky coasts in the geological record: Preserved or eroded? Insights from Miocene granitic rocky shorelines and modern examples.
Published: 2022-12-14
Subjects: Earth Sciences, Geology
Most of modern shorelines are in net erosion. Among these, rocky shorelines are commonly punctuated, with alternating high relief cliffs an incised embayments which host “pocket beaches”. While multiple cases of ancient rocky shorelines associated with low relief ravinement surfaces have been documented in the geological record, deposits formed in pocket beaches and joint-cut hollows are more [...]
Shortening ice seasons and changing phenology affect under-ice lake thermal dynamics
Published: 2022-12-13
Subjects: Earth Sciences, Environmental Sciences
Temperate lakes worldwide are losing ice cover but the implications for under-ice thermal dynamics are poorly constrained. Using a 90-year record of ice phenology from a temperate lake, we examined trends, variability, and drivers of ice phenology. The onset of ice formation decreased by 23 days century-1 which can be largely attributed to warming air temperatures. Ice-off date has become [...]
Citizen and Machine Learning-aided High-resolution mapping of urban heat exposure and stress
Published: 2022-12-13
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Through conversion of land cover to more built-up, impervious surfaces, cities are creating hotter environments for urban residents. Existing measurements of heat and heat stress, however, are often insufficient to capture intra-urban variability of exposure. This study provides a replicable method for modeling air temperature, humidity, and heat stress over an urban area, engaging citizens in [...]
Correlation of geological complexes of the Khan-Tengri Mountain massif
Published: 2022-12-09
Subjects: Earth Sciences, Geology, Stratigraphy, Tectonics and Structure
Researchers of the border regions of Xinjiang and the Central Asian countries are actively discussing two alternative models for the relationships between the main structural units of the Tianshan mountains. Most researchers believe that the Kyrgyz Middle Tianshan wedges out to the east along the Atbashi-Inylchek-Nalati marginal fault. According to the second hypothesis, the structures of the [...]
Basin-scale hydrodynamics and physical connectivity in a Great Patagonian Lake
Published: 2022-12-07
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Patagonian lakes are one of the most unexplored aquatic environments on Earth, and little is known about their thermo-hydrodynamics and current trophic state. Meanwhile, increasing urbanization and industrialization in their catchments compromise their health. Here, we investigate Lake Llanquihue, one of the Earth's great freshwater bodies in Northern Patagonia, Chile. Still considered a pristine [...]