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Zircon geochronology reveals polyphase magmatism and crustal anatexis in the Buchan Block,NE Scotland:Implications for the Grampian Orogeny

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Geoscience Frontiers 2017年第6期8卷 1469-1478页

作者： T.E.Johnson C.L.kirkland D.R.Viete S.Fischer S.M.Reddy N.J.Evans B.J.McDonald department of Applied Geology The Institute for Geoscience Research(TIGeR)CET-Curtin NodeJohn de Laeter CentreCurtin UniversityPerthWA 6102Australia morton k.blaustein department of earth&planetary sciences Johns Hopkins UniversityOlin Hall3400 N Charles StreetBaltimoreMD 21218USA School of earth&Environmental Science University of St AndrewsIrvine BuildingNorth StreetSt AndrewsKY16 9ALScotlandUK

The type locality for high-temperature,low-pressure regional metamorphism,the Buchan Block in NE Scotland,exhibits profound differences to the rest of the Grampian Terrane.These differences have led some to regard the Buchan Block as an exotic crustal fragment comprising Precambrian basement gneisses and cover rocks thrust into their current position during Grampian orogenesis.Although rocks of the Buchan Block are now generally correlated with Dalradian strata elsewhere,the origin of the gneisses and the cause of the high heat flow and associated magmatism is debated.We report SIMS U-Pb and LA-ICPMS Hf isotopic data in zircon from high-grade rocks from the northeast(Inzie Head Gneiss)and northwest(Portsoy)corners of the Buchan Block.Around Inzie Head,upper amphibolite to granulite facies metasedimentary gneisses coexist with diorite sheets that were emplaced contemporaneously with partial melting of their host rocks,at least locally.U-Pb geochronology indicates a crystallisation age for the diorite of 486±9 Ma.Highly-deformed diorites within the Portsoy Gabbro have a crystallisation age of 493±8 Ma.Ages of ca.490 Ma for magmatism and high-grade metamorphism,which are broadly contemporaneous with ophiolite obduction and the onset of orogenesis,are significantly older than the established peak of Grampian metamorphism(ca.470 Ma).We propose a new model for the Grampian Orogeny involving punctuated tectonothermal activity due to tectonic switching during accretionary orogenesis.Rollback of a NW-dipping subduction zone at ca.490 Ma produced a back-arc environment(the Buchan Block)with associated arc magmatism and high dT/dP metamorphism.Arrival of an outboard arc resulted in shortening(the initial phase of the Grampian Orogeny)at ca.488 Ma.Rollback of a NW-dipping subduction zone to the SE of the ca.488 Ma suture began at 473 Ma and led to lithospheric-scale extension,decompression melting and advective heating of the middle crust,producing the widespread ca.470 Ma Grampian(classic Barrovian and Buchan)regional metam

关键词： Dalradian Grampian Orogeny Buchan Block Zircon geochronology Magmatism Metamorphism

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Phylogeography of the common hamster(Cricetus cricetus):paleoclimatic reconstructions of Late Pleistocene colonization

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Integrative Zoology 2023年第3期18卷 581-599页

作者： Natalia Yu.FEOkTISTOVA Ilya G.MESCHERSkY Georgy I.SHENBROT Andrey Yu.PUZACHENkO Sergey I.MESCHERSkY Pavel L.BOGOMOLOV Alexey V.SUROV A.N.Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Mitrani department of Desert Ecology Jacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevMidreshet Ben-GurionIsrael Institute of Geography Russian Academy of SciencesMoscowRussia

INTRODUCTION Anthropogenic activities and associated factors such as climate change and habitat destruction are causing the ongoing sixth mass extinction on earth,which is a major characteristic of the Anthropocene.Collectively,these factors pose the most serious environmental threat to the existence of civilization because it is irreversible.More than 500 species of mammals were found to be on the brink of extinction and likely to be lost within 20 years(Ceballos et al.2020).One example is the common hamster Cricetus cricetus(Linnaeus,1758).In 2020,this species was classified as Critically Endangered across its global range by the IUCN Red List(Banaszek et al.2020).The protection status of the common hamster was elevated by 4 levels at once—from Least Concern to Critically Endangered.Although the causes behind the dramatic decline of the species are not fully understood,one may suppose it stems from the negative impact of habitat degradation and even climate change(Banaszek et al.2020).

关键词： extinction suppose irreversible

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Are local plague endemicity and ecological characteristics of vectors and reservoirs related? A case study in north-east Tanzania

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Current Zoology 2009年第3期55卷 200-211页

作者： Anne LAUDISOIT Simon NEERINCkX Rhodes H.MAkUNDI Herwig LEIRS Boris R.kRASNOV Zoogeographical Research Unit University of Liège Evolutionary Ecology Group Department of BiologyUniversity of Antwerpen department of earth & Environmental sciences Katholieke Universiteit Leuven Celestijnenlaan Pest Management Centre Sokoine University of Agriculture Danish Pest Infestation Laboratory Department of Integrated Pest ManagementFaculty of Agricultural SciencesUniversity of Aarhus Mitrani department of Desert Ecology Swiss Institute for Dryland Environmental ResearchJacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevSede-Boqer Campus

The pattern of plague endemicity in Tanzania is characterized by continuous re-appearance of the disease in some locations,while in other neighbouring villages the disease has never or seldom been observed.To understand the reasons for this pattern,we studied small mammal and flea species composition,diversity and relative abundances in two plague-endemic and two plague-free locations.We asked(a)whether fleas more abundant in plague-endemic locations differ in their characteristic abundance and the degree of their host specificity from fleas more abundant in plague-free locations and(b)whether hosts most abundant in plague-endemic locations differ in the diversity of their flea assemblages from hosts most abundant in plague-free locations.We characterized(a)each host species by species richness and degree of taxonomic relatedness of its flea assemblages and(b)each flea species by its mean abundance and size,and degree of taxonomic relatedness of its host spectrum and compared their relative abundances between locations.No significant difference between plague-endemic and plague-free locations in either host density or any variable related to flea abundance or diversity was found.However,there was marginally significant effect of taxonomic distinctness of a flea assemblage harboured by a host on its probability to be more abundant in either plague-endemic or plague-free locations.Furthermore,hosts more abundant in plague-endemic locations tended to harbour closely-related fleas.Finally,while opportunistic and specialist fleas were equally distributed in both sets of locations,fleas exploiting distantly-related hosts were found mainly in plague-free locations during the rainy season.We suggest that the observed patterns might arise due to seasonal and spatial differences in local microclimatic conditions and landscape connectivity.

关键词：鼠疫跳蚤传染病疫情

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Mapping the magnetic field in the solar corona through magnetoseismology

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Science China(Technological sciences) 2020年第11期63卷 2357-2368页

作者： YANG ZiHao TIAN Hui TOMCZYk Steven morton Richard BAI XianYong SAMANTA Tanmoy CHEN YaJie School of earth and Space sciences Peking UniversityBeijing 100871China key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China High Altitude Observatory National Center for Atmospheric ResearchBoulderCO 80307USA department of Mathematics Physics and Electrical EngineeringNorthumbria UniversityNewcastle Upon Tyne NE18STUK department of Physics and Astronomy George Mason UniversityFairfaxVA 22030USA Johns Hopkins University Applied Physics Laboratory LaurelMD 20723USA Max Planck Institute for Solar System Research 37077 G¨ottingenGermany

Magnetoseismology,a technique of magnetic field diagnostics based on observations of magnetohydrodynamic(MHD)waves,has been widely used to estimate the field strengths of oscillating structures in the solar corona.However,previously magnetoseismology was mostly applied to occasionally occurring oscillation events,providing an estimate of only the average field strength or one-dimensional distribution of field strength along an oscillating structure.This restriction could be eliminated if we apply magnetoseismology to the pervasive propagating transverse MHD waves discovered with the Coronal Multi-channel Polarimeter(CoMP).Using several CoMP observations of the Fe xiii 1074.7 nm and 1079.8 nm spectral lines,we obtained maps of the plasma density and wave phase speed in the corona,which allow us to map both the strength and direction of the coronal magnetic field in the plane of sky.We also examined distributions of the electron density and magnetic field strength,and compared their variations with height in the quiet Sun and active regions.Such measurements could provide critical information to advance our understanding of the Sun's magnetism and the magnetic coupling of the whole solar atmosphere.

关键词： solar corona solar magnetic field waves magnetoseismology

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Soil and Crop Damages as a Result of Levee Breaches on Ohio and Mississippi Rivers

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Journal of earth Science and Engineering 2013年第3期3卷 139-158页

作者： kenneth R. Olson Lois Wright morton department of Natural Resources and Environmental sciences College of Agricultural Consumer and Environmental SciencesUniversity of Illinois Urbana 61801 Illinois USA department of Sociology College of Agriculture and Life Sciences Iowa State University AmesSO011 Iowa USA

Whenever levees on the Ohio or Mississippi rivers are breached, there are soil damages in the flooded areas that impact agricultural management capacities and crop productivity. Floodwaters coat the entire flooded land surface with sediments which include a variety of pollutants, nutrients and contaminants. The nature of the sediments in floodwaters varies with the topographical and land use characteristics of the watershed. The soil types, hydro-geologic features, volume of flow, time of year, agricultural use of fertilizers, pesticides, and other chemicals as well as upstream point sources such as sewage treatment plants, storm sewer drainage and other urban land uses will affect the extent of the contamination and fine scale remediation needed. Preliminary characterization and measurement of soils and sediment deposit at three locations that experienced recent natural and man induced levee breaches are analyzed to identify patterns of soil and crop damage. These findings provide guidance to the restoration of craters, gullies, land scoured areas and contaminated sediment depositional sites with a goal to improve decision-making, risk analysis and remedial effectiveness. Recommendations include: (1) improve characterization and measurement of eroded soils and distribution of sediment contaminants after levee breaching; (2) assess contamination effects on soil productivity and long term agricultural production in order to understand the impacts of flooding on agricultural soils; (3) evaluate reconstruction investments needed to repair levees based on return of the land to productivity and increased landscape resilience by reducing vulnerability to future flooding and levee breaching stress.

关键词：作物生产力土壤类型密西西比河大堤俄亥俄州水沉积物损失农业生产

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The Global Boundary Stratotype Section and Point （GSSP） for the base of the Pliensbachian Stage （Lower Jurassic）, Wine Haven, Yorkshire, Uk

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Episodes 2006年第2期29卷 93-106页

作者： Christian Meister Martin Aberhan Joachim Blau Jean-Louis Dommergues Susanne Feist-Burkhardt Ernie A. Hailwood Malcom Hart Stephen P. Hesselbos Mark W. Hounslow Mark Hylton Nicol morton kevin Page Greg D. Price Département de Géologie et de Paléontologie 1 route de Malagnou c.p. 6434 CH-1211 Genève 6 Switzerland Museum der Naturkunde Zentralinstitut der Humboldt-Universitat zu Berlin Institut für Palaiontolgie Invalidenstr. 43 D-10115 Berlin Germany Institut für Geowissenschaften Diezstrasse 15 D-35390 Giessen Germany Centre des sciences de la Terre de I＇Université de Bourgogne UMR CNRS 5561： Paléontologie analytique et Géologie sédimentaire 6 Boulevard Gabriel F-21100 Dijon. France department of Palaeontology The Natural History Museum Cromwell Road London SW7 5BD UK Core Magnetics The Green Sedbergh Cumbria LA10 5JS UK department of Geological sciences University of Plymouth Drake Circus Plymouth Devon PL4 8AA UK department of earth sciences University of Oxford Parks Road Oxford OXI 3PR UK CEMP Geography Dept. Lancaster Environment Centre Lancaster University Bailrigg Lancaster UK. LA1 4YB Le Chardon Quarrier Brugière F-07200 Vogüé France

Following votes by the Pliensbachian Working Group, the Jurassic Subcommission and the International Commission on Stratigraphy, IUGS ratified the proposed Global Boundary Stratotype Section and Point (GSSP) for the base of the Pliensbachian Stage (Lower Jurassic) at the base of bed 73b in the Wine Haven section, Robin Hood's Bay, Yorkshire Coast, Uk. This level contains the characteristic ammonite association Bifericeras donovani Dommergues and Meister and Apoderoceras sp. Complementary data include: a) Strontium-isotope stratigraphy, based on analysis of belemnites which yield a calcite 87Sr/86Sr ratio for the boundary level of 0.707425 and data supporting interpretation of continuous sedimentation; b) Belemnite oxygen-isotope data indicate a significant temperature drop (∼5 °C) across the boundary at this locality; c) A Transgressive Systems Tract (TST) initiated in the Aplanatum Subzone (uppermost Sinemurian) continues into the Lowermost Pliensbachian (Taylori Subzone); it forms part of a transgressive facies cycle sensu Graciansky et al. (1998); d) The Upper Sinemurian to lowermost Pliensbachian at Wine Haven section has a predominantly normal magnetic polarity, but two discrete reversed polarity magnetozones are present. The first spans much of the latest Sinemurian Aplanatum Subzone. It terminates ker. The second extends from the latest Oxynotum Subzone probably through to the lower part of the Raricostatum Subzone.

关键词：普连斯巴奇阶侏罗纪 GSSP 全球界线层型剖面点

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A survey of analytical methods for inclusion in a new energy-water nexus knowledge discovery framework

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Big earth Data 2018年第3期2卷 197-227页

作者： Melissa R.Allen Syed Mohammed Arshad Zaidi Varun Chandola April M.morton Christa M.Brelsford Ryan A.McManamay Binita kC Jibonananda Sanyal Robert N.Stewart Budhendra L.Bhaduri Computational Science and Engineering Division Oak Ridge National LaboratoryOak RidgeTNUSA Computer Science and Engineering department University at BuffaloBuffaloNYUSA Environmental sciences Division Oak Ridge National LaboratoryOak RidgeTNUSA Urban Dynamics Institute Oak Ridge National LaboratoryOak RidgeTNUSA

The energy-water nexus,or the dependence of energy on water and water on energy,continues to receive attention as impacts on both energy and water supply and demand from growing popula-tions and climate-related stresses are evaluated for future infra-structure planning.Changes in water and energy demand are related to changes in regional temperature,and precipitation extremes can affect water resources available for energy genera-tion for those regional populations.Additionally,the vulnerabilities to the energy and water nexus are beyond the physical infrastruc-tures themselves and extend into supporting and interdependent infrastructures.Evaluation of these vulnerabilities relies on the integration of the disparate and distributed data associated with each of the infrastructures,environments and populations served,and robust analytical methodologies of the data.A capability for the deployment of these methods on relevant data from multiple components on a single platform can provide actionable informa-tion for interested communities,not only for individual energy and water systems,but also for the system of systems that they com-prise.Here,we survey the highest priority data needs and analy-tical methods for inclusion on such a platform.

关键词： Energy-water nexus data analytics web portal

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