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Paleo-and Mesoarchean TTG-sanukitoid to high-K granite cycles in the southern São Francisco craton,SE Brazil

Geoscience Frontiers 2022年第5期13卷 153-168页

作者： Claudio de Morisson Valeriano Caio Vinicius Gabrig Turbay Henrique Bruno Antonio Simonetti Monica Heilbron Samuel Moreira Bersan rob strachan Universidade do Estado do Rio de Janeiro Faculdade de GeologiaRua São Francisco Xavier 524/4006-BMaracanãRio de JaneiroBrazil Universidade Federal do Sul da Bahia Centro de Formação em Ciências AmbientaisPorto SeguroBahiaBrazil University of Portsmouth School of EnvironmentGeography and GeosciencesBurnaby BuildingBurnaby RoadPortsmouth PO13QLUnited Kingdom University of Notre Dame Department of Civil and Environmental Engineering and Earth Sciences46556United States

The generation of the continental crust is widely accepted to have taken place predominantly in the Archean,when TTG magmatism associated with greenstone-belt supracrustal succession development was typically followed by emplacement of high-K granites before crustal *** study focuses on the Campos Gerais complex(CGC),which is an Archean granite-greenstone belt lithological association in a tectonic window located in the southwesternmost portion of the São Francisco craton(SFC).The CGC is an important segment of Paleo-to Mesoarchean continental crust to be integrated into paleogeographic reconstructions prior to the transition into the *** investigation reports field relationships,28 major and trace element compositions,U–Pb(zircon)geochronological results,and Hf and Sm–Nd isotope data for orthogneiss and amphibolite *** results indicate that the CGC records a complex Archean crustal evolution,where voluminous 2.97 Ga TTG tonalites and trondhjemites(ε_(Nd)(t)=-4.7;T_(DM)=3.24 Ga)were followed by 2.89 Ga sanukitoid tonalite production(ε_(Nd)(t)=-1.9;T_(DM)=3.02 Ga),broadly coeval with the development of the Fortaleza de Minas and Pitangui *** events are interpreted to represent the initial stage of an important subduction-accretion tectonic cycle,which ended with the emplacement of 2.82–2.81 Ga high-K leucogranites and migmatization of the TTG-sanukitoid crust,with hybrid and two-mica,peraluminous compositions(ε_(Nd)(t)=-8.0 to-8.6;T_(DM)=3.57–3.34 Ga).The presence of inherited zircons with207Pb/206Pb ages of 3.08 Ga,3.29 Ga,3.55 Ga and 3.62 Ga indicates that the Mesoarchean tectonic processes involved reworking of Meso-to Eo-archean *** TTG magmatism took place at ca.2.77 Ga represented by juvenile tonalite stocks(ε_(Nd)(t)=+1.0 to-1.5;T_(DM)=2.80–2.88 Ga)which intrude the TTG-greenstone belt *** stabilization was attained by 2.67 Ga,allowing for the emplacement of within-plate thol

关键词： Crustal evolution Sm–Nd Lu–Hf LA-ICPMS zircon U–Pb

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A brief history of the Rheic Ocean

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Geoscience Frontiers 2012年第2期3卷 125-135页

作者： R.Damian Nance Gabriel Gutirrez-Alonso J.Duncan Keppie Ulf Linnemann J.Brendan Murphy Cecilio Quesada rob A.strachan Nigel H.Woodcock Department of Geological Sciences 316 Clippinger Laboratories Ohio University Departamento de Geología Universidad de Salamanca 33708 Salamanca Departamento de Geología Regional Instituto de Geología Universidad Nacional Autónoma de Mxico Senckenberg Naturhistorische Sammlungen Dresden Museum fur Mineralogie und Geologie Konigsbrucker Landstra βe 159D-01109 DresdenGermany Department of Earth Sciences St.Francis Xavier University Instituto Geolóogico y Minero de Espaa Ríos Rosas 2328003 MadridSpain School of Earth & Environmental Sciences University of Portsmouth Department of Earth Sciences University of Cambridge Downing StreetCambridge CB2 3EQUK

The Rheic Ocean was one of the most important oceans of the Paleozoic Era. It lay between Laurentia and Gondwana from the Early Ordovician and closed to produce the vast Ouachita- Alleghanian-Variscan orogen during the assembly of Pangea. Rifting began in the Cambrian as a continua- tion of Neoproterozoic orogenic activity and the ocean opened in the Early Ordovician with the separation of several Neoproterozoic arc terranes from the continental margin of northern Gondwana along the line of a former suture. The rapid rate of ocean opening suggests it was driven by slab pull in the outboard Iapetus Ocean. The ocean reached its greatest width with the closure of Iapetus and the accretion of the peri- Gondwanan arc terranes to Laurentia in the Silurian. Ocean closure began in the Devonian and continued through the Mississippian as Gondwana sutured to Laurussia to form Pangea. The ocean consequently plays a dominant role in the Appalachian-Ouachita orogeny of North America, in the basement geology of southern Europe, and in the Paleozoic sedimentary, structural and tectonothermal record from Middle America to the Middle East. Its closure brought the Paleozoic Era to an end.

关键词： Rheic Ocean Variscan-Alleghanian-Ouachita orogen Pangea North America Europe

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Neoarchean and Rhyacian TTG-Sanukitoid suites in the southern S?o Francisco Paleocontinent,Brazil:Evidence for diachronous change towards modern tectonics

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Geoscience Frontiers 2020年第5期11卷 1763-1787页

作者： Henrique Bruno Vitalino Elizeu Monica Heilbron Claudio de Morisson Valeriano rob strachan Mike Fowler Samuel Bersan Hugo Moreira Ivo Dussin Luiz Guilherme do Eirado Silva Miguel Tupinamba Julio Almeida Carla Neto Craig Storey Universidade Do Estado Do Rio de Janeiro Faculdade de GeologiaTektosGrupo de Pesquisa Em GeotectonicaRua Sao Francisco Xavier 524MaracanaRio de JaneiroBrazil University of Portsmouth School of Earth and Environmental SciencesBurnaby BuildingBurnaby RoadPortsmouthUK Universit€at Salzburg Department of Geography and GeologyKapitelgasse4-65020SalzburgAustria Universidade Federal de Ouro Preto Departamento de GeologiaCampus Morro Do CruzeiroOuro PretoMGBrazil Laboratorio de Geocronologia e Isotopos Radiog^enicos Universidade Do Estado Do Rio de JaneiroRua Sao Francisco Xavier 524MaracanaRio de JaneiroBrazil

The southern portion of the Sao Francisco Palaeocontinent in Brazil is denoted by Archean nuclei and Paleoproterozoic magmatic arcs that were amalgamated during Siderian to Orosirian orogenic processes(ca.2.4-2.1 Ga).New isotopic U-Pb in zircon and Sm-Nd whole rock combined with major and trace element composition analyses constrain the crystallization history of the Neoarchean Piedade block(at ca.2.6 Ga)and the Paleoproterozoic Mantiqueira Complex(ca.2.1-1.9 Ga).These therefore display quite different magmatic histories prior to their amalgamation at ca.2.05 ***-Nd and Rb-Sr isotopes imply a mixed mantle-crustal origin for the samples in both units.A complete Palaeoproterozoic orogenic cycle,from subduction to collision and collapse,is recorded in the Piedade Block and the Mantiqueira *** to Orosirian subduction processes(ca.2.2-2.1 Ga)led to the generation of coeval(ca.2.16 Ga)TTG suites and sanukitoids,followed by late(2.10-2.02 Ga)high-K granitoids that mark the collisional *** collisional accretion of the Mantiqueira Complex against the Piedade Block at 2.08-2.04 Ga is also recorded by granulite facies metamorphism in the latter terrane,along the Ponte Nova suture *** collisional stage was closely followed by the emplacement of within-plate tholeiites at ca.2.04 Ga and by alkaline rocks(syenites and enriched basic rocks)at ca.1.98 Ga,marking the transition to an extensional tectonic *** discovery of two episodes of TTG and sanukitoid magmatism,one during the Neoarchean in the Piedade Complex and another during the Rhyacian in the Mantiqueira Complex,indicates that the onset of subduction-related melting of metasomatized mantle was not restricted to Neoarchean times,as generally believed,but persisted much later into the Paleoproterozoic.

关键词： Geodynamics High Ba–Sr granitoids Diachronous TTG-Sanukitoid transition Paleoproterozoic Mantiqueira complex

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Risk mapping of wildlife-vehicle collisions across thestate of Montana,USA:a machine-learning approach forimbalanced data along rural roads

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Transportation Safety and Environment 2024年第3期6卷 124-132页

作者： Matthew Bell Yiyi Wang rob Ament Western Transportation Institute Montana State University2327 University WayBozemanMT 59717USA School of Engineering San Francisco State University1600 Holloway AveSan FranciscoCA 94132USA

Wildlife-vehicle collisions(WVCs)with large animals are estimated to cost the USA over 8 billion USD in property damage,tens of thousands of human injuries and nearly 200 human fatalities each *** WVCs occur on rural roads and are not collected evenly among road segments,leading to imbalanced *** are a disproportionate number of analysis units that have zero WVC cases when investigating large geographic areas for collision *** units with zero WVCs can reduce prediction accuracy and weaken the coefficient estimates of statistical learning *** study demonstrates that the use of the synthetic minority over-sampling technique(SMOTE)to handle imbalanced WVC data in combination with statistical and machine-learning models improves the ability to determine seasonal WVC risk across the rural highway network in Montana,*** array of regularized variables describing landscape,road and traffic were used to develop negative binomial and random forest models to infer WVC rates per 100 million vehicle miles *** random forest model is found to work particularly well with SMOTE-augmented data to improve the prediction accuracy of seasonal WVC ***-augmented data are found to improve accuracy when predicting crash risk across fine-grained grids while retaining the characteristics of the original *** analyses suggest that SMOTE augmentation mitigates data imbalance that is encountered in seasonally divided WVC *** research provides the basis for future risk-mapping models and can potentially be used to address the low rates of WVCs and other crash types along rural roads.

关键词： wildlife-vehicle collisions machine learning SMOTE negative binomial risk mapping

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年轻的玄武质洋弧地壳如何转变为长英质大陆地壳：以西准噶尔为例

年轻的玄武质洋弧地壳如何转变为长英质大陆地壳：以西准噶尔为例

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2023年中国地球科学联合学术年会

作者：尹继元肖文交孙敏 Mike Fowler Andrew C.Kerr 王涛 rob strachan 黄河陈文陶再礼

年轻玄武质洋弧地壳如何转变为成熟大陆地壳仍是地球科学领域的一个关键科学问题。在本文中,我们通过对新疆西准噶尔古生代侵入岩进行锆石U-Pb年龄和Hf-O同位素数据的综合分析,揭示出四期岩浆活动:早寒武世至早奥陶世(515至486 Ma);早... 详细信息

年轻玄武质洋弧地壳如何转变为成熟大陆地壳仍是地球科学领域的一个关键科学问题。在本文中,我们通过对新疆西准噶尔古生代侵入岩进行锆石U-Pb年龄和Hf-O同位素数据的综合分析,揭示出四期岩浆活动:早寒武世至早奥陶世(515至486 Ma);早奥陶世至中泥盆世(445至392 Ma);早石炭世(343至310 Ma)和晚石炭世至中二叠世(309至259 Ma)。这些岩浆活动在时空分布上有一定的变化。所有岩浆岩都显示出一致的高锆石Hf和全岩Nd同位素值,但锆石氧同位素存在显著的变化。

关键词：大陆地壳侵入岩同位素准噶尔

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Carbon dioxide enrichment affected flower numbers transiently and increased successful post-pollination development stably but without altering final acorn production in mature pedunculate oak (Quercus robur L.)

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Journal of Forestry Research 2024年第4期35卷 1-12页

作者： Ryan McClory Richard H.Ellis Martin Lukac Jo Clark Carolina Mayoral Kris M.Hart Andrew R.G.Plackett A.rob MacKenzie School of Agriculture Policy and DevelopmentUniversity of ReadingAgricultureEarley GateWhiteknights RoadPO Box 237Reading RG66EUUK Faculty of Forestry and Wood Sciences Czech University of Life Sciences PraguePrague 165000Czechia Future Trees Trust Harwell Innovation CentreBuilding 173Curie AvenueHarwellOxford OX110QGUK Birmingham Institute of Forest Research University of BirminghamEdgbastonBirmingham B152TTUK School of Biosciences University of BirminghamEdgbastonBirmingham B152TTUK School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK

Acorn production in oak(Quercus spp.)shows considerable inter-annual variation,known as masting,which provides a natural defence against seed predators but a highly-variable supply of acorns for uses such as in commercial tree planting each *** emissions of greenhouse gases have been very widely reported to influence plant growth and seed or fruit size and quantity via the‘fertilisation effect’that leads to enhanced *** examine if acorn production in mature woodland communities will be affected by further increase in CO_(2),the contents of litter traps from a Free Air Carbon Enrichment(FACE)experiment in deciduous woodland in central England were analysed for numbers of flowers and acorns of pedunculate oak(Quercus robur L.)at different stages of development and their predation levels under ambient and elevated CO_(2) ***-annual variation in acorn numbers was considerable and cyclical between 2015 and 2021,with the greatest numbers of mature acorns in 2015,2017 and 2020 but almost none in *** numbers of flowers,enlarged cups,immature acorns,empty acorn cups,and galls in the litter traps also varied amongst years;comparatively high numbers of enlarged cups were recorded in 2018,suggesting *** at this site is a fruit maturation masting species(i.e.,the extent of abortion of pollinated flowers during acorn development affects mature acorn numbers greatly).Raising the atmospheric CO_(2) concentration by 150μL L^(−1),from early 2017,increased the numbers of immature acorns,and all acorn evidence(empty cups+immature acorns+mature acorns)detected in the litter traps compared to ambient controls by 2021,but did not consistently affect the numbers of flowers,enlarged cups,empty cups,or mature *** number of flowers in the elevated CO_(2) plots’litter traps was greater in 2018 than 2017,one year after CO_(2) enrichment began,whereas numbers declined in ambient *** with CO_(2) also increased the number o

关键词： Quercus robur L. Acorns Masting Pedunculate oak Carbon dioxide

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Risk mapping of wildlife-vehicle collisions across the state of Montana,USA:a machine-learning approach for imbalanced data along rural roads

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Transportation Safety and Environment 2024年第03期 149-157页

作者： Matthew Bell Yiyi Wang rob Ament Western Transportation Institute Montana State University School of Engineering San Francisco State University

Wildlife-vehicle collisions(WVCs) with large animals are estimated to cost the USA over 8 billion USD in property damage,tens of thousands of human injuries and nearly 200 human fatalities each *** WVCs occur on rural roads and are not collected evenly among road segments,leading to imbalanced *** are a disproportionate number of analysis units that have zero WVC cases when investigating large geographic areas for collision *** units with zero WVCs can reduce prediction accuracy and weaken the coefficient estimates of statistical learning *** study demonstrates that the use of the synthetic minority oversampling technique(SMOTE) to handle imbalanced WVC data in combination with statis tical and machine-learning models improves the ability to determine seasonal WVC risk across the rural highway network in Montana,*** array of regularized variables describing landscape,road and traffic were used to develop negative binomial and random forest models to infer WVC rates per 100million vehicle miles *** random forest model is found to work particularly well with SMOTE-augmented data to improve the prediction accuracy of seasonal WVC ***-augmented data are found to improve accuracy when predicting crash risk across fine-grained grids while retaining the characteristics of the original *** analyses suggest that SMOTE augmentation mitigates data imbalance that is encountered in seasonally divided WVC *** research provides the basis for future risk-mapping models and can potentially be used to address the low rates of WVCs and other crash types along rural roads.

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Drought Tolerance and Recovery of the Sedge Carex planostachys (Cyperaceae) from Central Texas Woodlands

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American Journal of Plant Sciences 2024年第9期15卷 746-765页

作者： E. rob Wayne Oscar William Van Auken Natural Sciences Department St. Philips College San Antonio USA Department of Integrative Biology The University of Texas at San Antonio San Antonio USA

Carex planostachys Kunze (Cyperaceae, Cedar sedge) is an herbaceous species in a genus commonly inhabiting mesic or hydric habitats. Carex planostachys is found in arid and semi-arid Juniperus woodlands. Arid conditions impose survival challenges to plants in dry areas. Some plants have plasticity responses to soil water content and continued normal though reduced functions through droughts, but most herbaceous plants do not survive. Limited previous studies have suggested C. planostachys is tolerant of drought. Physiological responses of C. planostachys from Juniperus woodlands was examined is this study to determine how long plants could survive without water and if they are capable of recovery from very negative water potentials beyond what is considered the permanent wilting point for most herbaceous plants. Plants were placed in pots in partial shade in this experiment. Water loss from the soil with plants was an inverse 2nd order polynomial function with soil water decreasing from 32% to 8% by day 28 of the study. Leaf water potential was also an inverse 2nd order polynomial function but did not decline significantly until 14 days without watering. Leaf water potential was −10.0 MPa after 35 days without watering. Non-watered plants Anet, (photosynthetic rate) was significantly lower compared to the water treatment by day 21 as was stomatal conductance and transpiration. When non-watered plants were watered after 21, 28 or 35 days, full recovery of physiological responses occurred within 7 days. The length of time that C. planostachys was able to withstand drought was greater than the annual trends in lack of precipitation during springtime in this area. Carex planostachys can photosynthesize at water stress between −8 and −10 MPa. Carex planostachys drought and shade tolerance enables it to occupy an understory niche devoid of other herbaceous plants.

关键词： CO2 Uptake Conductance Gas Exchange Photosynthesis Respiration Transpiration Water Stress Water Potential.

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乡村旅游精英公共服务动机的结构维度研究

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旅游学刊 2024年第9期39卷 91-105页

作者：徐少癸韩佳钰陈思榕 rob LAW 章牧福建师范大学文化旅游与公共管理学院福建福州350117 暨南大学深圳旅游学院广东深圳518053 南洋理工大学黄金辉传播与信息学院新加坡637718 澳门大学亚太经济与管理研究所中国澳门999078 澳门大学工商管理学院中国澳门999078

乡村旅游精英在乡村振兴、消除贫困、促进乡村旅游可持续发展等方面发挥着至关重要的作用。然而,作为中国旅游研究领域的热点议题,乡村旅游精英的动机研究却往往被简单化和边缘化。因此,文章基于中国乡土文化背景,聚焦乡村旅游精英这一... 详细信息

乡村旅游精英在乡村振兴、消除贫困、促进乡村旅游可持续发展等方面发挥着至关重要的作用。然而,作为中国旅游研究领域的热点议题,乡村旅游精英的动机研究却往往被简单化和边缘化。因此,文章基于中国乡土文化背景,聚焦乡村旅游精英这一特定群体,利用扎根理论对乡村旅游精英公共服务动机的结构维度进行探索性研究。研究发现,乡村旅游精英公共服务动机由乡土情结、公共利益承诺、社会认可与支持、自我奉献精神和政策制定吸引力5个维度组成。其中,公共利益承诺、自我奉献精神和政策制定吸引力3个维度具有普适性,乡土情结和社会认可与支持则是文章基于中国乡土社会背景发现的新维度。乡村旅游精英公共服务动机是一个复杂的多维结构体系,各维度相互关联、相互影响,共同构成了乡村旅游精英公共服务动机的驱动因素。以上结论对乡村旅游精英公共服务动机研究具有一定的理论贡献,同时也为乡村旅游目的地管理、评估乡村旅游精英提供了针对性建议。

关键词：乡村旅游精英公共服务动机乡村旅游乡村振兴扎根理论

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探索DNA数据驱动器

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科技纵览 2024年第3期 30-36,4页

作者： rob Carlson 不详

我们每天都会产生很多数据,包括电子邮件、文本、照片和社交媒体帖子等。虽然这些内容大多不值得保存,但每天我们都在默默地作出不删除这些数据的决定。我们把它们保存在某个地方,可能是手机上、电脑硬盘上或者云上,最终它们都会被存档... 详细信息

我们每天都会产生很多数据,包括电子邮件、文本、照片和社交媒体帖子等。虽然这些内容大多不值得保存,但每天我们都在默默地作出不删除这些数据的决定。我们把它们保存在某个地方,可能是手机上、电脑硬盘上或者云上,最终它们都会被存档,大多数情况下是在磁带上。此外,现在各种设备和传感器都将数据传输到网络上,汽车、飞机和其他交通工具的数据也要存储以备后用。物联网上的数十亿物品都会产生数据,所有这些信息都需要存储在某个地方。

关键词：电子邮件电脑硬盘物联网数据传输其他交通工具社交媒体传感器

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