Preprints
Filtering by Subject: Physical Sciences and Mathematics
Restricted rupture evolution of the 2022 Mw 6.7 Luding China earthquake
Published: 2022-10-25
Subjects: Earth Sciences, Physical Sciences and Mathematics
On September 5, 2022, a strike-slip earthquake with a moment magnitude (Mw) 6.7 occurred along the Moxi segment of the Xianshuihe fault zone in Luding, Sichuan province, China. To estimate the rupture evolution of the 2022 Luding earthquake, we inverted teleseismic P-waves by applying the Potency Density Tensor Inversion, a novel method that can estimate fault geometry and source process. We [...]
Sedimentological Characteristics, and Provenance of the Late Cretaceous Sediment in the Eastern Dahomey Basin
Published: 2022-10-24
Subjects: Physical Sciences and Mathematics
Field studies of outcrop samples from part of the Dahomey basin, southeastern Nigeria, were investigated to unravel the lithofacies distribution and provenance of the basin. Granulometric analysis of the sandstone facies of the Araromi Formation has been studied. Histograms of the sediments exhibit both unimodal and bimodal trends. The cumulative curve of the studied samples Is typical of fluvial [...]
GEOCHEMICAL AND MINERALOGICAL STUDY OF THE CRETACEOUS SEDIMENTS IN KERI KERI, FIKA, GONGILA, AND BIMA SANDSTONE FORMATION BORNU BASIN, NORTH-EASTERN NIGERIA
Published: 2022-10-24
Subjects: Physical Sciences and Mathematics
The mineralogical and geochemical composition of Cretaceous and Tertiary sediments of the Bornu Basin, northeastern Nigeria penetrated by Kanadi Wells, have been studied towards deducing aspects of their derivation and deposition. The sediments comprising the Bima Sandstone Formation, sandy-shale Gongila Formation, and, clayey and shaley Fika Formation are mainly composed of quartz (35-58%) and [...]
GEOCHEMICAL SURVEY AND POTENTIAL MINERALIZATION INVESTIGATION OF ILERO AND ITS ENVIRONS OYO STATE, NIGERIA
Published: 2022-10-24
Subjects: Physical Sciences and Mathematics
Ilero and its environs are part of the Kajola local Government area, Oyo State, and fall within the basement complex of southwestern Nigeria. The research work was focused on the geological mapping of the area and the study of the different rock and minerals units to determine the mineral resources of the area using petrographic, geochemical, and XRD analysis. The geochemical analysis showed the [...]
SHALLOW COMPOSITION AND STRUCTURE OF THE UPPER PART OF THE EXHUMED SAN GABRIEL FAULT, CALIFORNIA: IMPLICATIONS FOR FAULT PROCESSES AND SEISIMIC PROPERTIES
Published: 2022-10-22
Subjects: Physical Sciences and Mathematics
Quantifying shallow fault zone structure and characteristics is critical for accurately modeling the complex mechanical behavior of earthquakes as energy moves within faults from depth. We examine macro- to microstructures, mineralogy, and properties from drill core analyses of fault-related rocks in the steeply plunging ALT-B2 geotechnical borehole (total depth of 493 m) across the San Gabriel [...]
Advances in understanding subglacial meltwater drainage from past ice sheets
Published: 2022-10-22
Subjects: Physical Sciences and Mathematics
Meltwater drainage beneath ice sheets is a fundamental consideration for understanding ice-bed conditions and bed-modulated ice flow, with potential impacts on terminus behavior and ice-shelf mass balance. While contemporary observations reveal the presence of basal water movement in the subglacial environment and inferred styles of drainage, the geological record, including sediments and [...]
In Defense of Metrics: Metrics Sufficiently Encode Typical Human Preferences Regarding Hydrological Model Performance
Published: 2022-10-19
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Building accurate rainfall-runoff models is an integral part of hydrological science and practice. The variety of modeling goals and applications have led to a large suite of evaluation metrics for these models. Yet, hydrologists still put considerable trust into visual judgment, although it is unclear whether such judgment agrees or disagrees with existing quantitative metrics. In this study, we [...]
The impact of Holocene deglaciation and glacial dynamics on the landscapes and geomorphology of Potter Peninsula, King George Island (Isla 25 Mayo), NW Antarctic Peninsula
Published: 2022-10-19
Subjects: Earth Sciences, Geology, Geomorphology, Glaciology, Physical Sciences and Mathematics, Sedimentology
The timing and impact of deglaciation and Holocene readvances on the terrestrial continental margins of the Antarctic Peninsula have been well-studied but are still debated. Potter Peninsula on King George Island (Isla 25 de Mayo), South Shetland Islands (SSI), NW Antarctic Peninsula has a detailed assemblage of glacial landforms and stratigraphic exposures for constraining deglacial landscape [...]
Holocene deglaciation and glacier readvances on the Fildes Peninsula and King George Island (Isla 25 de Mayo), South Shetland Islands, NW Antarctic Peninsula
Published: 2022-10-18
Subjects: Physical Sciences and Mathematics
To provide insights into glacier-climate dynamics of the South Shetland Islands (SSI), NW Antarctic Peninsula, we present a new deglaciation and readvance model for the Bellingshausen Ice Cap (BIC) on Fildes Peninsula and for King George Island/Isla 25 de Mayo (KGI) ~62°S. Deglaciation on KGI began after c. 15 ka cal BP and had progressed to within present-day limits on the Fildes Peninsula, its [...]
Fault Friction Derived from Fault Bend Influence on Coseismic Slip During the 2019 Ridgecrest Mw 7.1 Mainshock
Published: 2022-10-18
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
The variation of stress on faults is important for our understanding of fault friction and the dynamics of earthquake ruptures. However, we still have little observational constraints on their absolute magnitude, or their variations in space and in time over the seismic cycle. Here we use a new geodetic imaging technique to measure the 3D coseismic slip vectors along the 2019 Ridgecrest surface [...]
Planetary Scale Analysis of the Morphology of River Channels and Channel Belt Deposits
Published: 2022-10-18
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
The morphology of a river and its channel belt is in part the product of ecological, hydrological and tectonic processes shaping the terrestrial landscape. River morphology is critical for understanding their physical evolution through time, and in predicting the future behavior of rivers and floods. To date, there is no global-scale, quantitative study of the morphology of rivers and their [...]
New reference materials, analytical procedures, and data reduction strategies for Sr isotope measurements in geological materials by LA-MC-ICP-MS
Published: 2022-10-17
Subjects: Physical Sciences and Mathematics
Laser ablation multi-collector mass spectrometry (LA-MC-ICP-MS) has emerged as the technique of choice for in situ measurements of Sr isotopes in geological minerals. However, the method poses analytical challenges and there is no widely adopted standardised approach to collecting these data or correcting the numerous potential isobaric inferences. Here, we outline practical analytical procedures [...]
Dislocation and disclination densities in experimentally deformed polycrystalline olivine
Published: 2022-10-15
Subjects: Physical Sciences and Mathematics
We report a comprehensive dataset characterizing and quantifying the dislocation density in the crystallographic frame (ρ_α^c) and disclination density (ρ_θ) in fine-grained polycrystalline olivine deformed in uniaxial compression or torsion, at 1000 °C and 1200 °C, under a confining pressure of 300 MPa. Finite strains range from 0.11 up to 8.6 % and stresses reach up to 1073 MPa. The data set is [...]
Trait-based modeling revealed higher microbial diversity leads to greater ecological resilience in response to an ecosystem disturbance
Published: 2022-10-15
Subjects: Biogeochemistry, Earth Sciences, Environmental Microbiology and Microbial Ecology Life Sciences, Microbiology, Oceanography, Oil, Gas, and Energy, Physical Sciences and Mathematics, Sustainability, Terrestrial and Aquatic Ecology
To quantitatively understand the ecological resilience of an ecosystem with specialized habitats, we focused on deep-sea microbial communities and simulated the response of diverse microbes in specialized habitats to a pulse ecosystem disturbance - the Deepwater Horizon Oil Spill in the Gulf of Mexico. Two microbial communities with equivalent metabolic libraries were acclimated to the presence [...]
Inclination and heterogeneity of layered geological sequences influence dike-induced ground deformation
Published: 2022-10-15
Subjects: Physical Sciences and Mathematics
Constraints on the amount and pattern of ground deformation induced by dike emplacement are important for assessing potential eruptions. The vast majority of ground deformation inversions made for volcano monitoring during volcanic unrest assume that dikes are emplaced in either an elastic-half space (a homogeneous crust) or a crust made of horizontal layers with different mechanical properties. [...]