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description Publicationkeyboard_double_arrow_right Article 2024 United KingdomPublisher:Springer Science and Business Media LLC Antonio Costa; Leonardo Mingari; Victoria C. Smith; Giovanni Macedonio; Danielle McLean; Arnau Folch; Jeonghyun Lee; Sung-Hyo Yun;AbstractThe Millennium Eruption of Paektu volcano, on the border of China and North Korea, generated tephra deposits that extend >1000 km from the vent, making it one of the largest eruptions in historical times. Based on observed thicknesses and compositions of the deposits, the widespread tephra dispersal is attributed to two eruption phases fuelled by chemically distinct magmas that produced both pyroclastic flows and fallout deposits. We used an ensemble-based method with a dual step inversion, in combination with the FALL3D atmospheric tephra transport model, to constrain these two different phases. The volume of the two distinct phases has been calculated. The results indicate that about 3-16 km3 (with a best estimate of 7.2 km3) and 4-20 km3 (with a best estimate of 9.3 km3) of magma were erupted during the comendite and trachyte phases of the eruption, respectively. Eruption rates of up to 4 × 108 kg/s generated plumes that extended 30-40 km up into the stratosphere during each phase.
Communications Earth... arrow_drop_down Communications Earth & Environment; Oxford University Research ArchiveOther literature type . Article . 2024 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1038/s43247-023-01162-0&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Communications Earth... arrow_drop_down Communications Earth & Environment; Oxford University Research ArchiveOther literature type . Article . 2024 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type , Article 2024 United KingdomPublisher:Elsevier BV Authors: Shnizai, Z; Walker, R; Tsutsumi, H;Shnizai, Z; Walker, R; Tsutsumi, H;The city of Kabul, Afghanistan, lies within the Kabul Block, which is bounded by the Sarobi, Gardez and Paghman fault, the northern extension of the Chaman fault, accommodating oblique convergence between the Indian and Eurasian plates. In this paper, we describe the geologic structure and tectonic geomorphology of the northeast-striking Paghman fault and a ∼10-km-long portion of the Chaman fault using a combination of field observations and remote sensing data, and assess evidence for rupturing in the 1505 historical earthquake. The Paghman fault is predominantly a left-lateral strike-slip fault with a minor dip-slip component along the eastern margin of the Paghman Mountains. The Chaman and Paghman faults displaces Paleogene to Quaternary units with clear displacement of recent deposits. Continuous left-lateral movement of the both faults have caused stream deflection, capturing, abandonment, and finally, incision of alluvial deposits inside the Kabul Basin. We identify several stages in the alluvial fan development and displacement that were once a continuous unit displaced left-laterally as a single fan but are now incised by beheaded and offset stream channels. An approximately 30-km-long active fault trace is identified with geomorphic evidence of recent faulting and vertical offset ∼0.5–3 m, which we interpret is related to the historical 1505 earthquake in the area along the Chaman and Paghman faults. Our observations indicate significant along-strike variations in faults trace geometry. The seismic event comprises several fault segments separated by discontinuities such as stepovers. The two faults have accumulated enough elastic strain to cause a larger earthquake since the 1505 quake.
Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023License: CC BYData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.jseaes.2023.105925&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023License: CC BYData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.jseaes.2023.105925&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type 2024 United KingdomPublisher:Elsevier BV Paul G. Albert; Danielle McLean; Hannah M. Buckland; Takehiko Suzuki; Gwydion Jones; Richard A. Staff; Sophie Vineberg; Ikuko Kitaba; Keitaro Yamada; Hiroshi Moriwaki; Daisuke Ishimura; Ken Ikehara; Christina J. Manning; Takeshi Nakagawa; Victoria C. Smith;Long sedimentary successions extracted for palaeoclimate research regularly preserve volcanic ash (tephra) fall from explosive eruptions and are increasingly used to elucidate the timing and scale of past events. This study investigates the non-visible tephra (cryptotephra) layers preserved in the annually laminated and intensively 14 C dated sediments of Lake Suigetsu (SG14 core), Japan. The cryptotephra investigations reported here focus on the Late-glacial to early Holocene sediments that were deposited between two visible tephra layers, the Ulleungdo (U)-Oki (10.2 ka) and the Sambe ‘Sakate’ (19.6 ka), and consequently span an interval of abrupt climate change making any newly identified cryptotephra layers invaluable chrono-stratigraphic markers. Using major and trace element volcanic glass compositions the cryptotephra are used to assign provenance to chrono-stratigraphically relevant eruption units. Five new cryptotephra layers are identified within this time interval. Three cryptotephra layers are from Kyushu volcanoes (SG14-1337 and SG14-1554 [Sakurajima]; and SG14-1806 [Kirishima]), all of which offer important chronological constraints on archaeological (Jomon) cultural transitions in southern Japan during the last termination. Another cryptotephra (SG14-1579), is assigned to activity on Niijima Island providing the first known distal occurrence and age of the eruption. Finally, the SG14-1798 cryptotephra precisely dated at 16,619 ± 74 IntCal20 yrs BP (2σ) is linked to Asama (As) volcano and more precisely the later phases of the As-YKU eruption. This discovery greatly expands the distribution of ash fall from this multi-phased eruption at Asama volcano, which affected an area in the region of 120,000 km2. Refining the timing of the eruption and the distribution of As-YKU ash fall is important as it offers an excellent chrono- and climato45 stratigraphic marker suitable for assessing spatial variability in environmental response to past climate change during the termination of the last glacial.
Cronfa at Swansea Un... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023Data sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Cronfa at Swansea Un... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023Data sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type , Article 2024 United KingdomPublisher:European Association of Geochemistry W. Wang; A.J. Dickson; M.A. Stow; M. Dellinger; K.W. Burton; P.S. Savage; R.G. Hilton; J. Prytulak;Recent analytical advances in the measurement of rhenium (Re) isotope ratios allow its potential as a palaeoredox and chemical weathering proxy to be explored. However, a successful isotopic proxy must be grounded by an understanding of its composition and behaviour in the solid Earth. Here, we present Re concentrations and Re isotopic (δ187Re) compositions for a well-characterised sequence of lavas from Hekla volcano, Iceland. The concentration of Re varies from 0.02 to 1.4 ng/g, decreasing from basalt to more evolved lavas. We show that the crystallisation and removal of magnetite is responsible for the Re decrease in this system. By contrast, δ187Re values for the same suite of samples show a relatively narrow range (−0.45 to −0.22 ‰), suggesting minimal resolvable Re isotope fractionation between magnetite and the silicate melt. Together with other samples, including mid-ocean ridge basalts, these first igneous data can be used to estimate a baseline for terrestrial materials (δ187Re = −0.33 ± 0.15 ‰, 2 s.d., n = 14), from which low-temperature Re isotope variations in Earth’s surficial environments can be assessed, alongside the global isotope mass balance of Re.
Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2024Data sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2024Data sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.7185/geochemlet.2402&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type , Article 2023 United KingdomPublisher:Geological Society of America Gallo, RI; Ort, MH; Iacovino, K; Silleni, A; Smith, VC; Giordano, G; Isaia, R; Boro, J;doi: 10.1130/ges02651.1
Abstract The 39.8-ka Campanian Ignimbrite was emplaced during a large caldera-forming eruption of Campi Flegrei near Naples, Italy. The ignimbrite is found up to 80 km from the caldera, and co-ignimbrite ash-fall deposits occur 3200 km away. The proximal and distal stratigraphy of the Campanian Ignimbrite has not been definitively correlated due to the dissimilar appearance of the proximal and distal deposits, a lack of medial exposures, and the inconsistency and heterogeneity of the proximal stratigraphy. Here, we document the major-element glass-shard chemistry, matrix componentry, and lithic componentry of the proximal and distal stratigraphic sequences of the ignimbrite to attempt to correlate the units. The results of these disparate observations taken together suggest that the established stratigraphic units cannot be directly and uniquely correlated between the proximal and distal regions and that neither the proximal nor distal stratigraphy provides a record of the entire eruptive sequence. However, the characteristics studied can be used to demarcate eruptive phases that are connected to some of the defined units in the proximal and distal stratigraphy.
Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023License: CC BY NCData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1130/ges02651.1&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023License: CC BY NCData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1130/ges02651.1&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publication2023 United KingdomPublisher:Elsevier BV Funded by:UKRI | The Oxford DTP in Environ...UKRI| The Oxford DTP in Environmental ResearchBrookfield, A; Cassidy, M; Weber, G; Rӑzvan-Gabriel, P; Bachmann, O; Stock, MJ;Volatile exsolution is widely considered to be capable of generating magmatic overpressure and triggering volcanic eruptions. Despite its role as an eruption trigger, exsolution-driven overpressurisation is relatively poorly understood. Part of the problem is that thermodynamic models do not consider how the behaviour of small quantities of magma scales up to reservoir level – where variations in temperature and crystallinity become important. In contrast, many thermomechanical models focus only on magma injection, and do not consider how overpressure evolves spatially or temporally, when related to crystallisation and volatile exsolution. Here, we use Rhyolite-MELTS to track exsolution-driven overpressure during cooling for a variety of natural compositions, storage pressures, initial volatile contents and magmatic XH2O (molar H2O/ (CO2 + H2O)). We then couple these outputs to a thermal model to determine the timescales and spatial extent of overpressurisation with varying volatile content. We find that the highest overpressures occur in magmas which are initially at their H2O solubility limit, with the addition or removal of H2O resulting in a decrease in peak overpressure. We also find that maximum overpressure decreases with the addition of CO2 (decreasing XH2O) at typical magma storage pressures of 100–230 MPa. The higher overpressures generated at the volatile ‘sweet spot’ have a greater potential to trigger eruptions – or to favour their initiation by making the system more susceptible to other triggers, such as magma injection. The reduction in overpressure with increasing or decreasing initial H2O suggests that triggering by volatile exsolution is less likely for these magmas. Peak overpressure at the volatile sweet spot also coincides with an increased incidence of explosive eruptions at water contents ∼4–5.5 wt%. This suggests that higher magmatic overpressures may produce more explosive eruptions, by driving faster initial ascent rates and decreasing outgassing efficiency in the conduit. Our thermal modelling demonstrates that, for small magmatic systems, exsolution-driven overpressurisation can operate on timescales which are much shorter than the crustal relaxation timescale. In these cases, overpressure cannot be dissipated by a visco-elastic crustal response, and therefore has the potential to trigger a volcanic eruption.
Oxford University Re... arrow_drop_down Oxford University Research Archive; Journal of Volcanology and Geothermal ResearchOther literature type . Article . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.euAccess Routeshybrid 0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research Archive; Journal of Volcanology and Geothermal ResearchOther literature type . Article . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publication2023 United KingdomPublisher:Elsevier BV Authors: Watson, EB; Cherniak, DJ; Nichols, CIO; Weiss, BP;Watson, EB; Cherniak, DJ; Nichols, CIO; Weiss, BP;The ferrimagnetic mineral magnetite (Fe3O4) is abundant in banded iron formation (BIFs), and has the potential to provide U—Pb or Pb—Pb age information on these rocks because it incorporates small amounts of U during growth. Combined with age measurements, paleomagnetic studies of BIF magnetites may also yield insight into the history of Earth's magnetic field and its relationship to early evolution of Earth's interior and atmosphere. Reliable magnetite ages utilizing Pb isotopes require knowledge of Pb diffusion in the magnetite structure. For this reason, we undertook an experimental investigation of Pb diffusion in magnetite by diffusing Pb2+ ions into pre-polished slabs of natural magnetite oriented parallel to {001} or {111}. A mixture of PbSO4 and Fe2O3 was used as a surface powder source to supply Pb2+ diffusant at the sample surface and at the same time buffer the oxygen fugacity of the system at magnetite-hematite (MH)—a typical fO2 for banded iron formations (BIFs) due to the common presence of both iron oxides (and where Pb2+ is stable relative to other Pb valence states). Diffusion experiments spanned temperatures of 500–675 °C and durations of 75 to 2035 h. Following each experiment, in-diffused Pb was depth-profiled using Rutherford backscattering spectroscopy (RBS) and Pb diffusivities were calculated from the profiles using an infinite half-space diffusion model. The following diffusion law for Pb2+ in magnetite is based upon 12 independent diffusivity measurements: DPb (m2·s−1) = (9 × 10−17 m2·s−1) exp.(−98,000 J·mol−1)/RT) where the uncertainties in the pre-exponential constant and activation energy are ±6% and ± 15%, respectively. Pb diffusion in magnetite over the temperature range of our study is orders of magnitude slower than projected for other divalent cations based on down-temperature extrapolation of previously measured diffusion laws (e.g., for Mn2+, Fe2+, Co2+, and Ni2+). This finding is encouraging in terms of the potential suitability of magnetite for U—Pb age determinations of BIFs and other magnetite-bearing rocks. Indeed, classical Dodson closure temperatures well above 500 °C are not unrealistic in cases where magnetite crystals having large diffusion domains (e.g., >100 μm in radius) are cooled relatively rapidly (e.g., at 100 °C/MYr). This is of particular significance for paleomagnetic studies, since the Curie temperature of magnetite is 580 °C and therefore the age of magnetization in magnetite-bearing rocks may be directly dated. However, slow cooling of magnetites having small diffusion domains can lead to Pb loss at temperatures of 200 °C or lower. Pb mobilization is evaluated for various time-temperature scenarios that involve both heating and cooling as well as “closed-loop” time-temperature paths. We conclude that U—Pb or Pb—Pb age determinations of BIF magnetites are potentially reliable, but isotopic results should be assessed in concert with knowledge of the thermal history of the host rock and the effective grain size of the magnetites.
Oxford University Re... arrow_drop_down Oxford University Research Archive; Chemical GeologyOther literature type . Article . 2023 . Peer-reviewedLicense: CC BY NCadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.euAccess Routeshybrid 0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research Archive; Chemical GeologyOther literature type . Article . 2023 . Peer-reviewedLicense: CC BY NCadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type , Article 2023 United KingdomPublisher:Elsevier BV Sam Woor; David S.G. Thomas; Julie A. Durcan; Sallie L. Burrough; Ash Parton;The preservation and interpretation of past external forcings within sedimentary archives can be complicated. Marine proxy records show that, throughout the Mid-Late Quaternary, monsoon rainfall in south-east Arabia has varied at precessional timescales (∼ 23 ka). By contrast, terrestrial environmental records from the region, such as speleothems and palaeolake sequences, generally only capture rainfall variability at eccentricity (∼ 100 ka) timescales and geomorphological archives rarely record events over multiple glacial cycles. Previous work has suggested that the alluvial fan systems of the Hajar Mountains record aggradation coincident with precessional peaks because of more northerly Indian Ocean Summer Monsoon (IOSM) rainfall, relative to present. However, the alluvial record is complex: there is a growing body of ‘anomalous’ aggradation age data from periods of precessional minima and it is spatially uneven, mainly being derived from fans at either the northern- or southern-most extents of the western side of the mountains. We present optically stimulated luminescence (OSL) ages of alluvial aggradation from new sites in the central portion of the western and eastern sides of the Hajar mountains. Sedimentary units that show evidence of more sustained flow conditions, such as coarse conglomerate deposition and the development of thick floodplain deposits, typically date to periods of higher IOSM rainfall at precessional timescales. Sites where there is evidence of deposition under more ephemeral flow conditions, like today, yield ages corresponding to precessional minima. We synthesise these data with similarly interpreted alluvial and lacustrine deposits from across the region, employing a hierarchical clustering approach to generate clusters of ages representing periods of increased hydrological activity. This objective approach to regional chronological data suggests that ten periods of more sustained hydrological activity are evidenced across the Hajar region, broadly aligning to precessional and eccentricity peaks over the last 400 ka. These clusters show that Hajar fans predominately aggrade because of increasing rainfall over their catchments, with the central ages of clusters often aligning with the onset of precessional forcing. Hajar alluvial systems preserve important records of Quaternary climate variability over long timescales in an arid region where terrestrial records are scarce due to preservation issues.
Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2024License: CC BYData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2024License: CC BYData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.quascirev.2023.108384&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2023 United KingdomPublisher:Elsevier BV Funded by:UKRI | DE-ICERUKRI| DE-ICERFallon, C; Truyen, E; Eakins, D; Pervier, H; Pervier, MLA; Aceves Lopez, M;Accurate determination of the mechanical response of atmospheric ice is key to understanding the risks associated with ice impact on aircraft during flight. Two types of atmospheric ice which are of particular interest to the aerospace industry are studied. Rime and Glaze ice are each manufactured in an icing wind tunnel facility under controlled conditions. Rime ice is accreted at a temperature of −20◦C, and Glaze ice is accreted at −5 ◦C. Quasi-static threepoint bend tests are performed on both types of ice to understand the effect of accretion temperature, and therefore microstructure, on strength. The results indicate that the ice accretion temperature, and thus microstructure, has a significant influence on the bending strength. On average, the bending strength of Rime ice is 9.0 ± 0.18 MPa compared to 4.4 ± 0.093 MPa for Glaze. The comparatively lower accretion temperature of Rime results in smaller grain sizes and higher bending strength. In contrast, the effective modulus appears insensitive to ice microstructure, with an average value of 3.5±0.12 GPa for Rime compared to 3.6±0.098 GPa for Glaze. Furthermore, the results indicate that both the bending strength and effective modulus are insensitive to the ice storage time. Innovate UK: 113155 Rolls-Royce plc
Oxford University Re... arrow_drop_down Oxford University Research Archive; Materials Today CommunicationsOther literature type . Article . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.mtcomm.2023.107461&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.euAccess Routeshybrid 0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research Archive; Materials Today CommunicationsOther literature type . Article . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.mtcomm.2023.107461&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2023 United KingdomPublisher:Elsevier BV Authors: Sujitapan, C; Kendall, JM; Chambers, JE; Yordkayhun, S;Sujitapan, C; Kendall, JM; Chambers, JE; Yordkayhun, S;A ground model of a shallow landslide in rainfall-induced slope failure of Thungsong, Nakhon Si Thammarat, southern Thailand is developed through an integrated geophysical approach, utilising electrical resistivity tomography and P-wave seismic refraction tomography (SRT) methods. Those two methods were applied to assess landslide structure and study deformation mechanisms along four profiles. Beside the four profiles there is another profile, which was acquired near an borehole and used for the calibration with geological data. Our results show subsurface structures in terms of the ground model used to determine stratigraphic layers, zones of saturation or groundwater table, and significant differences between the landslide slip material and the underlying bedrock. The clay-rich zones (resistivity less than 500 Ωm) in the colluvium on the relatively steep slope, show enhanced potential for landslides. This silty clay plays an important role for landslide activation in this site. Moreover, a combination of steep slopes, shallow basement rocks overlain by clay-rich colluvium, and seasonally high rain fall leads to landslides in the region. The ground model produced by geophysical imaging for this region achieves a comprehensive understanding of the structure and lithology of a complex landslide system and overcomes the limitations of remote-sensing data or isolated intrusive sampling techniques alone.
Journal of Asian Ear... arrow_drop_down Journal of Asian Earth Sciences: X; Oxford University Research Archive; NERC Open Research ArchiveOther literature type . Article . 2024 . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Journal of Asian Ear... arrow_drop_down Journal of Asian Earth Sciences: X; Oxford University Research Archive; NERC Open Research ArchiveOther literature type . Article . 2024 . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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description Publicationkeyboard_double_arrow_right Article 2024 United KingdomPublisher:Springer Science and Business Media LLC Antonio Costa; Leonardo Mingari; Victoria C. Smith; Giovanni Macedonio; Danielle McLean; Arnau Folch; Jeonghyun Lee; Sung-Hyo Yun;AbstractThe Millennium Eruption of Paektu volcano, on the border of China and North Korea, generated tephra deposits that extend >1000 km from the vent, making it one of the largest eruptions in historical times. Based on observed thicknesses and compositions of the deposits, the widespread tephra dispersal is attributed to two eruption phases fuelled by chemically distinct magmas that produced both pyroclastic flows and fallout deposits. We used an ensemble-based method with a dual step inversion, in combination with the FALL3D atmospheric tephra transport model, to constrain these two different phases. The volume of the two distinct phases has been calculated. The results indicate that about 3-16 km3 (with a best estimate of 7.2 km3) and 4-20 km3 (with a best estimate of 9.3 km3) of magma were erupted during the comendite and trachyte phases of the eruption, respectively. Eruption rates of up to 4 × 108 kg/s generated plumes that extended 30-40 km up into the stratosphere during each phase.
Communications Earth... arrow_drop_down Communications Earth & Environment; Oxford University Research ArchiveOther literature type . Article . 2024 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Communications Earth... arrow_drop_down Communications Earth & Environment; Oxford University Research ArchiveOther literature type . Article . 2024 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type , Article 2024 United KingdomPublisher:Elsevier BV Authors: Shnizai, Z; Walker, R; Tsutsumi, H;Shnizai, Z; Walker, R; Tsutsumi, H;The city of Kabul, Afghanistan, lies within the Kabul Block, which is bounded by the Sarobi, Gardez and Paghman fault, the northern extension of the Chaman fault, accommodating oblique convergence between the Indian and Eurasian plates. In this paper, we describe the geologic structure and tectonic geomorphology of the northeast-striking Paghman fault and a ∼10-km-long portion of the Chaman fault using a combination of field observations and remote sensing data, and assess evidence for rupturing in the 1505 historical earthquake. The Paghman fault is predominantly a left-lateral strike-slip fault with a minor dip-slip component along the eastern margin of the Paghman Mountains. The Chaman and Paghman faults displaces Paleogene to Quaternary units with clear displacement of recent deposits. Continuous left-lateral movement of the both faults have caused stream deflection, capturing, abandonment, and finally, incision of alluvial deposits inside the Kabul Basin. We identify several stages in the alluvial fan development and displacement that were once a continuous unit displaced left-laterally as a single fan but are now incised by beheaded and offset stream channels. An approximately 30-km-long active fault trace is identified with geomorphic evidence of recent faulting and vertical offset ∼0.5–3 m, which we interpret is related to the historical 1505 earthquake in the area along the Chaman and Paghman faults. Our observations indicate significant along-strike variations in faults trace geometry. The seismic event comprises several fault segments separated by discontinuities such as stepovers. The two faults have accumulated enough elastic strain to cause a larger earthquake since the 1505 quake.
Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023License: CC BYData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023License: CC BYData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.jseaes.2023.105925&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type 2024 United KingdomPublisher:Elsevier BV Paul G. Albert; Danielle McLean; Hannah M. Buckland; Takehiko Suzuki; Gwydion Jones; Richard A. Staff; Sophie Vineberg; Ikuko Kitaba; Keitaro Yamada; Hiroshi Moriwaki; Daisuke Ishimura; Ken Ikehara; Christina J. Manning; Takeshi Nakagawa; Victoria C. Smith;Long sedimentary successions extracted for palaeoclimate research regularly preserve volcanic ash (tephra) fall from explosive eruptions and are increasingly used to elucidate the timing and scale of past events. This study investigates the non-visible tephra (cryptotephra) layers preserved in the annually laminated and intensively 14 C dated sediments of Lake Suigetsu (SG14 core), Japan. The cryptotephra investigations reported here focus on the Late-glacial to early Holocene sediments that were deposited between two visible tephra layers, the Ulleungdo (U)-Oki (10.2 ka) and the Sambe ‘Sakate’ (19.6 ka), and consequently span an interval of abrupt climate change making any newly identified cryptotephra layers invaluable chrono-stratigraphic markers. Using major and trace element volcanic glass compositions the cryptotephra are used to assign provenance to chrono-stratigraphically relevant eruption units. Five new cryptotephra layers are identified within this time interval. Three cryptotephra layers are from Kyushu volcanoes (SG14-1337 and SG14-1554 [Sakurajima]; and SG14-1806 [Kirishima]), all of which offer important chronological constraints on archaeological (Jomon) cultural transitions in southern Japan during the last termination. Another cryptotephra (SG14-1579), is assigned to activity on Niijima Island providing the first known distal occurrence and age of the eruption. Finally, the SG14-1798 cryptotephra precisely dated at 16,619 ± 74 IntCal20 yrs BP (2σ) is linked to Asama (As) volcano and more precisely the later phases of the As-YKU eruption. This discovery greatly expands the distribution of ash fall from this multi-phased eruption at Asama volcano, which affected an area in the region of 120,000 km2. Refining the timing of the eruption and the distribution of As-YKU ash fall is important as it offers an excellent chrono- and climato45 stratigraphic marker suitable for assessing spatial variability in environmental response to past climate change during the termination of the last glacial.
Cronfa at Swansea Un... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023Data sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.quascirev.2023.108376&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Cronfa at Swansea Un... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023Data sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type , Article 2024 United KingdomPublisher:European Association of Geochemistry W. Wang; A.J. Dickson; M.A. Stow; M. Dellinger; K.W. Burton; P.S. Savage; R.G. Hilton; J. Prytulak;Recent analytical advances in the measurement of rhenium (Re) isotope ratios allow its potential as a palaeoredox and chemical weathering proxy to be explored. However, a successful isotopic proxy must be grounded by an understanding of its composition and behaviour in the solid Earth. Here, we present Re concentrations and Re isotopic (δ187Re) compositions for a well-characterised sequence of lavas from Hekla volcano, Iceland. The concentration of Re varies from 0.02 to 1.4 ng/g, decreasing from basalt to more evolved lavas. We show that the crystallisation and removal of magnetite is responsible for the Re decrease in this system. By contrast, δ187Re values for the same suite of samples show a relatively narrow range (−0.45 to −0.22 ‰), suggesting minimal resolvable Re isotope fractionation between magnetite and the silicate melt. Together with other samples, including mid-ocean ridge basalts, these first igneous data can be used to estimate a baseline for terrestrial materials (δ187Re = −0.33 ± 0.15 ‰, 2 s.d., n = 14), from which low-temperature Re isotope variations in Earth’s surficial environments can be assessed, alongside the global isotope mass balance of Re.
Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2024Data sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2024Data sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.7185/geochemlet.2402&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type , Article 2023 United KingdomPublisher:Geological Society of America Gallo, RI; Ort, MH; Iacovino, K; Silleni, A; Smith, VC; Giordano, G; Isaia, R; Boro, J;doi: 10.1130/ges02651.1
Abstract The 39.8-ka Campanian Ignimbrite was emplaced during a large caldera-forming eruption of Campi Flegrei near Naples, Italy. The ignimbrite is found up to 80 km from the caldera, and co-ignimbrite ash-fall deposits occur 3200 km away. The proximal and distal stratigraphy of the Campanian Ignimbrite has not been definitively correlated due to the dissimilar appearance of the proximal and distal deposits, a lack of medial exposures, and the inconsistency and heterogeneity of the proximal stratigraphy. Here, we document the major-element glass-shard chemistry, matrix componentry, and lithic componentry of the proximal and distal stratigraphic sequences of the ignimbrite to attempt to correlate the units. The results of these disparate observations taken together suggest that the established stratigraphic units cannot be directly and uniquely correlated between the proximal and distal regions and that neither the proximal nor distal stratigraphy provides a record of the entire eruptive sequence. However, the characteristics studied can be used to demarcate eruptive phases that are connected to some of the defined units in the proximal and distal stratigraphy.
Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023License: CC BY NCData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2023License: CC BY NCData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1130/ges02651.1&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publication2023 United KingdomPublisher:Elsevier BV Funded by:UKRI | The Oxford DTP in Environ...UKRI| The Oxford DTP in Environmental ResearchBrookfield, A; Cassidy, M; Weber, G; Rӑzvan-Gabriel, P; Bachmann, O; Stock, MJ;Volatile exsolution is widely considered to be capable of generating magmatic overpressure and triggering volcanic eruptions. Despite its role as an eruption trigger, exsolution-driven overpressurisation is relatively poorly understood. Part of the problem is that thermodynamic models do not consider how the behaviour of small quantities of magma scales up to reservoir level – where variations in temperature and crystallinity become important. In contrast, many thermomechanical models focus only on magma injection, and do not consider how overpressure evolves spatially or temporally, when related to crystallisation and volatile exsolution. Here, we use Rhyolite-MELTS to track exsolution-driven overpressure during cooling for a variety of natural compositions, storage pressures, initial volatile contents and magmatic XH2O (molar H2O/ (CO2 + H2O)). We then couple these outputs to a thermal model to determine the timescales and spatial extent of overpressurisation with varying volatile content. We find that the highest overpressures occur in magmas which are initially at their H2O solubility limit, with the addition or removal of H2O resulting in a decrease in peak overpressure. We also find that maximum overpressure decreases with the addition of CO2 (decreasing XH2O) at typical magma storage pressures of 100–230 MPa. The higher overpressures generated at the volatile ‘sweet spot’ have a greater potential to trigger eruptions – or to favour their initiation by making the system more susceptible to other triggers, such as magma injection. The reduction in overpressure with increasing or decreasing initial H2O suggests that triggering by volatile exsolution is less likely for these magmas. Peak overpressure at the volatile sweet spot also coincides with an increased incidence of explosive eruptions at water contents ∼4–5.5 wt%. This suggests that higher magmatic overpressures may produce more explosive eruptions, by driving faster initial ascent rates and decreasing outgassing efficiency in the conduit. Our thermal modelling demonstrates that, for small magmatic systems, exsolution-driven overpressurisation can operate on timescales which are much shorter than the crustal relaxation timescale. In these cases, overpressure cannot be dissipated by a visco-elastic crustal response, and therefore has the potential to trigger a volcanic eruption.
Oxford University Re... arrow_drop_down Oxford University Research Archive; Journal of Volcanology and Geothermal ResearchOther literature type . Article . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.euAccess Routeshybrid 0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research Archive; Journal of Volcanology and Geothermal ResearchOther literature type . Article . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publication2023 United KingdomPublisher:Elsevier BV Authors: Watson, EB; Cherniak, DJ; Nichols, CIO; Weiss, BP;Watson, EB; Cherniak, DJ; Nichols, CIO; Weiss, BP;The ferrimagnetic mineral magnetite (Fe3O4) is abundant in banded iron formation (BIFs), and has the potential to provide U—Pb or Pb—Pb age information on these rocks because it incorporates small amounts of U during growth. Combined with age measurements, paleomagnetic studies of BIF magnetites may also yield insight into the history of Earth's magnetic field and its relationship to early evolution of Earth's interior and atmosphere. Reliable magnetite ages utilizing Pb isotopes require knowledge of Pb diffusion in the magnetite structure. For this reason, we undertook an experimental investigation of Pb diffusion in magnetite by diffusing Pb2+ ions into pre-polished slabs of natural magnetite oriented parallel to {001} or {111}. A mixture of PbSO4 and Fe2O3 was used as a surface powder source to supply Pb2+ diffusant at the sample surface and at the same time buffer the oxygen fugacity of the system at magnetite-hematite (MH)—a typical fO2 for banded iron formations (BIFs) due to the common presence of both iron oxides (and where Pb2+ is stable relative to other Pb valence states). Diffusion experiments spanned temperatures of 500–675 °C and durations of 75 to 2035 h. Following each experiment, in-diffused Pb was depth-profiled using Rutherford backscattering spectroscopy (RBS) and Pb diffusivities were calculated from the profiles using an infinite half-space diffusion model. The following diffusion law for Pb2+ in magnetite is based upon 12 independent diffusivity measurements: DPb (m2·s−1) = (9 × 10−17 m2·s−1) exp.(−98,000 J·mol−1)/RT) where the uncertainties in the pre-exponential constant and activation energy are ±6% and ± 15%, respectively. Pb diffusion in magnetite over the temperature range of our study is orders of magnitude slower than projected for other divalent cations based on down-temperature extrapolation of previously measured diffusion laws (e.g., for Mn2+, Fe2+, Co2+, and Ni2+). This finding is encouraging in terms of the potential suitability of magnetite for U—Pb age determinations of BIFs and other magnetite-bearing rocks. Indeed, classical Dodson closure temperatures well above 500 °C are not unrealistic in cases where magnetite crystals having large diffusion domains (e.g., >100 μm in radius) are cooled relatively rapidly (e.g., at 100 °C/MYr). This is of particular significance for paleomagnetic studies, since the Curie temperature of magnetite is 580 °C and therefore the age of magnetization in magnetite-bearing rocks may be directly dated. However, slow cooling of magnetites having small diffusion domains can lead to Pb loss at temperatures of 200 °C or lower. Pb mobilization is evaluated for various time-temperature scenarios that involve both heating and cooling as well as “closed-loop” time-temperature paths. We conclude that U—Pb or Pb—Pb age determinations of BIF magnetites are potentially reliable, but isotopic results should be assessed in concert with knowledge of the thermal history of the host rock and the effective grain size of the magnetites.
Oxford University Re... arrow_drop_down Oxford University Research Archive; Chemical GeologyOther literature type . Article . 2023 . Peer-reviewedLicense: CC BY NCadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.euAccess Routeshybrid 0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research Archive; Chemical GeologyOther literature type . Article . 2023 . Peer-reviewedLicense: CC BY NCadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type , Article 2023 United KingdomPublisher:Elsevier BV Sam Woor; David S.G. Thomas; Julie A. Durcan; Sallie L. Burrough; Ash Parton;The preservation and interpretation of past external forcings within sedimentary archives can be complicated. Marine proxy records show that, throughout the Mid-Late Quaternary, monsoon rainfall in south-east Arabia has varied at precessional timescales (∼ 23 ka). By contrast, terrestrial environmental records from the region, such as speleothems and palaeolake sequences, generally only capture rainfall variability at eccentricity (∼ 100 ka) timescales and geomorphological archives rarely record events over multiple glacial cycles. Previous work has suggested that the alluvial fan systems of the Hajar Mountains record aggradation coincident with precessional peaks because of more northerly Indian Ocean Summer Monsoon (IOSM) rainfall, relative to present. However, the alluvial record is complex: there is a growing body of ‘anomalous’ aggradation age data from periods of precessional minima and it is spatially uneven, mainly being derived from fans at either the northern- or southern-most extents of the western side of the mountains. We present optically stimulated luminescence (OSL) ages of alluvial aggradation from new sites in the central portion of the western and eastern sides of the Hajar mountains. Sedimentary units that show evidence of more sustained flow conditions, such as coarse conglomerate deposition and the development of thick floodplain deposits, typically date to periods of higher IOSM rainfall at precessional timescales. Sites where there is evidence of deposition under more ephemeral flow conditions, like today, yield ages corresponding to precessional minima. We synthesise these data with similarly interpreted alluvial and lacustrine deposits from across the region, employing a hierarchical clustering approach to generate clusters of ages representing periods of increased hydrological activity. This objective approach to regional chronological data suggests that ten periods of more sustained hydrological activity are evidenced across the Hajar region, broadly aligning to precessional and eccentricity peaks over the last 400 ka. These clusters show that Hajar fans predominately aggrade because of increasing rainfall over their catchments, with the central ages of clusters often aligning with the onset of precessional forcing. Hajar alluvial systems preserve important records of Quaternary climate variability over long timescales in an arid region where terrestrial records are scarce due to preservation issues.
Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2024License: CC BYData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.quascirev.2023.108384&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research ArchiveOther literature type . 2024License: CC BYData sources: Oxford University Research Archiveadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.quascirev.2023.108384&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2023 United KingdomPublisher:Elsevier BV Funded by:UKRI | DE-ICERUKRI| DE-ICERFallon, C; Truyen, E; Eakins, D; Pervier, H; Pervier, MLA; Aceves Lopez, M;Accurate determination of the mechanical response of atmospheric ice is key to understanding the risks associated with ice impact on aircraft during flight. Two types of atmospheric ice which are of particular interest to the aerospace industry are studied. Rime and Glaze ice are each manufactured in an icing wind tunnel facility under controlled conditions. Rime ice is accreted at a temperature of −20◦C, and Glaze ice is accreted at −5 ◦C. Quasi-static threepoint bend tests are performed on both types of ice to understand the effect of accretion temperature, and therefore microstructure, on strength. The results indicate that the ice accretion temperature, and thus microstructure, has a significant influence on the bending strength. On average, the bending strength of Rime ice is 9.0 ± 0.18 MPa compared to 4.4 ± 0.093 MPa for Glaze. The comparatively lower accretion temperature of Rime results in smaller grain sizes and higher bending strength. In contrast, the effective modulus appears insensitive to ice microstructure, with an average value of 3.5±0.12 GPa for Rime compared to 3.6±0.098 GPa for Glaze. Furthermore, the results indicate that both the bending strength and effective modulus are insensitive to the ice storage time. Innovate UK: 113155 Rolls-Royce plc
Oxford University Re... arrow_drop_down Oxford University Research Archive; Materials Today CommunicationsOther literature type . Article . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.mtcomm.2023.107461&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.euAccess Routeshybrid 0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Oxford University Re... arrow_drop_down Oxford University Research Archive; Materials Today CommunicationsOther literature type . Article . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.mtcomm.2023.107461&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article 2023 United KingdomPublisher:Elsevier BV Authors: Sujitapan, C; Kendall, JM; Chambers, JE; Yordkayhun, S;Sujitapan, C; Kendall, JM; Chambers, JE; Yordkayhun, S;A ground model of a shallow landslide in rainfall-induced slope failure of Thungsong, Nakhon Si Thammarat, southern Thailand is developed through an integrated geophysical approach, utilising electrical resistivity tomography and P-wave seismic refraction tomography (SRT) methods. Those two methods were applied to assess landslide structure and study deformation mechanisms along four profiles. Beside the four profiles there is another profile, which was acquired near an borehole and used for the calibration with geological data. Our results show subsurface structures in terms of the ground model used to determine stratigraphic layers, zones of saturation or groundwater table, and significant differences between the landslide slip material and the underlying bedrock. The clay-rich zones (resistivity less than 500 Ωm) in the colluvium on the relatively steep slope, show enhanced potential for landslides. This silty clay plays an important role for landslide activation in this site. Moreover, a combination of steep slopes, shallow basement rocks overlain by clay-rich colluvium, and seasonally high rain fall leads to landslides in the region. The ground model produced by geophysical imaging for this region achieves a comprehensive understanding of the structure and lithology of a complex landslide system and overcomes the limitations of remote-sensing data or isolated intrusive sampling techniques alone.
Journal of Asian Ear... arrow_drop_down Journal of Asian Earth Sciences: X; Oxford University Research Archive; NERC Open Research ArchiveOther literature type . Article . 2024 . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.jaesx.2023.100168&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert Journal of Asian Ear... arrow_drop_down Journal of Asian Earth Sciences: X; Oxford University Research Archive; NERC Open Research ArchiveOther literature type . Article . 2024 . 2023 . Peer-reviewedLicense: CC BYadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.jaesx.2023.100168&type=result"></script>'); --> </script>
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