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Reconstructing seafloor age distributions in lost ocean basins

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Geoscience Frontiers 2021年第2期12卷 769-780页

作者： simon williams Nicky M.Wright John Cannon Nicolas Flament R.Dietmar Müller Department of Geology Northwest UniversityXi’an710069China State Key Laboratory of Continental Dynamics Northwest UniversityXi’an710069China Research School of Earth Sciences The Australian National UniversityACT2601Australia ARC Centre of Excellence for Climate Extremes The Australian National UniversityACT2601Australia EarthByte Group School of GeosciencesUniversity of SydneyAustralia GeoQuEST Research Centre School of EarthAtmospheric and Life SciencesUniversity of WollongongNorthfields AvenueNSW2522Australia

Reconstructions of past seafloor age make it possible to quantify how plate tectonic forces,surface heat flow,ocean basin volume and global sea level have varied through geological ***,past ocean basins that have now been subducted cannot be uniquely reconstructed,and a significant challenge is how to explore a wide range of possible ***,we investigate possible distributions of seafloor ages from the late Paleozoic to present using published full-plate reconstructions and a new,efficient seafloor age reconstruction workflow,all developed using the open-source software *** test alternative reconstruction models and examine the influence of assumed spreading rates within the Panthalassa Ocean on the reconstructed history of mean seafloor age,oceanic heat flow,and the contribution of ocean basin volume to global sea *** reconstructions suggest variations in mean seafloor age of~15 Myr during the late Paleozoic,similar to the amplitude of variations previously proposed for the Cretaceous to *** reconstructed oceanic age-area distributions are broadly compatible with a scenario in which the long-period fluctuations in global sea level since the late Paleozoic are largely driven by changes in mean seafloor *** suggestions of a constant rate of seafloor production through time can be modelled using our workflow,but require that oceanic plates in the Paleozoic move slower than continents based on current reconstructions of continental motion,which is difficult to reconcile with geodynamic studies.

关键词： Plate reconstructions Sea level Seafloor spreading

Structural Basis of Interaction of Bipartite Nuclear Localization Signal from Agrobacterium VirD2 with Rice Importin-o

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Molecular Plant 2014年第6期7卷 1061-1064页

作者： Chiung-Wen Chang simon J. williams Rafael Miguez Couñago Bostjan Kobe School of Chemistry and Molecular Biosciences Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre University of Queensland Brisbane Qld 4072 Australia

Dear Editor, In the eukaryotic cell, the nuclear envelope separates genomic DNA from the rest of the cell, but ensures a molecu- lar communication between the nucleus and the cytoplasm through the nuclear pore complexes （NPCs）. Nuclear trans- port of macromolecules is an energy-dependent process, exemplified by the classical nuclear import pathway. In the cytoplasm, proteins containing classical nuclear localization signals （cNLSs） are recognized by a hetero-dimeric transport receptor （importin-α （Impα）：importin-β （Impl3） complex）. Impa is employed as an adaptor protein that specifically rec-ognizes the classical nuclear localization signal （cNLS） from the cargo protein （Marfori et al., 2011）. Translocation of the trimeric cargo：transport receptor import complex through the NPCs is mediated by transient interactions between Impβ and nucleoporins in the NPC. The directionality of the trans- port is imparted by the asymmetric distribution, between the cytoplasm and the nucleus, of the distinct nucleotide-bound （GTP/GDP） states of the small GTPase Ran （Tran et al., 2007）.

关键词： CRYSTAL-STRUCTURE TRANSFORMATION

Global kinematics of tectonic plates and subduction zones since the late Paleozoic Era

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Geoscience Frontiers 2019年第3期10卷 989-1013页

作者： Alexander Young Nicolas Flament Kayla Maloney simon williams Kara Matthews Sabin Zahirovic R.Dietmar Müller School of Earth and Environmental Sciences University of Wollongong EarthByte Group School of Geosciences The University of Sydney Sydney Informatics Hub The University of Sydney

Detailed global plate motion models that provide a continuous description of plate boundaries through time are an effective tool for exploring processes both at and below the Earth's surface. A new generation of numerical models of mantle dynamics pre-and post-Pangea timeframes requires global kinematic descriptions with full plate reconstructions extending into the Paleozoic(410 Ma). Current plate models that cover Paleozoic times are characterised by large plate speeds and trench migration rates because they assume that lowermost mantle structures are rigid and fixed through time. When used as a surface boundary constraint in geodynamic models, these plate reconstructions do not accurately reproduce the present-day structure of the lowermost mantle. Building upon previous work, we present a global plate motion model with continuously closing plate boundaries ranging from the early Devonian at 410 Ma to present *** analyse the model in terms of surface kinematics and predicted lower mantle structure. The magnitude of global plate speeds has been greatly reduced in our reconstruction by modifying the evolution of the synthetic Panthalassa oceanic plates, implementing a Paleozoic reference frame independent of any geodynamic assumptions, and implementing revised models for the Paleozoic evolution of North and South China and the closure of the Rheic Ocean. Paleozoic(410-250 Ma) RMS plate speeds are on average ～8 cm/yr, which is comparable to Mesozoic-Cenozoic rates of ～6 cm/yr on *** global median values of trench migration trend from higher speeds(～2.5 cm/yr) in the late Devonian to rates closer to 0 cm/yr at the end of the Permian(～250 Ma), and during the Mesozoic-Cenozoic(250-0 Ma) generally cluster tightly around ～1.1 cm/yr. Plate motions are best constrained over the past 130 Myr and calculations of global trench convergence rates over this period indicate median rates range between 3.2 cm/yr and 12.4 cm/yr with a present day median rate estimat

关键词： Tectonic reconstruction Paleozoic Plate velocities Subduction zone kinematics Lower mantle structure South China

Decoding earth’s plate tectonic history using sparse geochemical data

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Geoscience Frontiers 2020年第1期11卷 265-276页

作者： Michael G.Tetley Zheng-Xiang Li Kara J.Matthews simon E.williams R.Dietmar Müller EarthByte Group School of GeosciencesUniversity of SydneyNSWAustralia Seismological Laboratory California Institute of TechnologyPasadenaCAUSA Data61 CSIROAustralian Technology ParkNSWAustralia Earth Dynamics Research Group The Institute for Geoscience Research(TIGeR)School of Earth and Planetary SciencesCurtin University of TechnologyGPO Box U1987PerthWA 6845Australia

Accurately mapping plate boundary types and locations through time is essential for understanding the evolution of the plate-mantle system and the exchange of material between the solid Earth and surface ***,the complexity of the Earth system and the cryptic nature of the geological record make it difficult to discriminate tectonic environments through deep *** we present a new method for identifying tectonic paleo-environments on Earth through a data mining approach using global geochemical *** first fingerprint a variety of present-day tectonic environments utilising up to 136 geochemical data attributes in any available combination.A total of 38301 geochemical analyses from basalts aged from 5-0 Ma together with a well-established plate reconstruction model are used to construct a suite of discriminatory models for the first order tectonic environments of subduction and mid-ocean ridge as distinct from intraplate hotspot oceanic environments,identifying 41,35,and 39 key discriminatory geochemical attributes,*** training and validation,our model is applied to a global geochemical database of 1547 basalt samples of unknown tectonic origin aged between 1000-410 Ma,a relatively ill-constrained period of Earth’s evolution following the breakup of the Rodinia supercontinent,producing 56 unique global tectonic environment predictions throughout the Neoproterozoic and Early *** are used to discriminate between three alternative published Rodinia configuration models,identifying the model demonstrating the closest spatio-temporal consistency with the basalt record,and emphasizing the importance of integrating geochemical data into plate *** approach offers an extensible framework for constructing full-plate,deeptime reconstructions capable of assimilating a broad range of geochemical and geological observations,enabling next generation Earth system models.

关键词： Plate tectonics Geochemistry Geodynamics Supercontinents Rodinia Big data

基于GPlates平台的“深时”板块构造重建:数据库现状与应用实例

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高校地质学报 2020年第4期26卷 444-463页

作者：林成发刘少峰 simon williams 中国地质大学(北京)地球科学与资源学院北京100083 中国地质大学(北京)地质过程与矿产资源国家重点实验室北京100083 西北大学地质学系西安710069

板块构造重建是大地构造领域一项关键的研究工作,是构建"深时数字地球"(Deep-time Digital Earth, DDE)的重要途径。板块重建工作需要整合地球科学多个研究领域、海量的数据,同时又是地球动力学和气候模拟等研究的重要约束条件。因此,... 详细信息

板块构造重建是大地构造领域一项关键的研究工作,是构建"深时数字地球"(Deep-time Digital Earth, DDE)的重要途径。板块重建工作需要整合地球科学多个研究领域、海量的数据,同时又是地球动力学和气候模拟等研究的重要约束条件。因此,追踪目前国际主流的板块重建所需的数据库以及板块重建工具的最新进展和应用为了解板块重建研究的前沿提供全面的信息。文章系统介绍了支持板块构造重建研究的多个主流数据库,着重描述数据库的数据格式、数据获取方式及数据如何支持基于GPlates平台的板块构造重建。为了阐述大地构造研究相关数据库在板块重建研究中的应用,此次研究从板块构造重建的三个不同层次出发,列举了多个最新的板块重建模型及其在探索地球系统演化方面的意义。最后,结合DDE项目的相关任务,对250 Ma以来全球板块构造和变形的演化、量化大地构造在地球系统演化中的作用、超大陆旋回中的古大陆和古海洋构造重建以及前中生代(>250 Ma)全球板块运动模型重建这四个关键科学问题作出了新的展望。

关键词：构造重建 GPlates平台数据库地幔动力学模型

The impact of a non-tidal ocean loading model of high temporal resolution on geodetic GPS height time series

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The impact of a non-tidal ocean loading model of high tempor...

The Prevalence of High Grade Cervical Intraepithelial Neoplasia (CIN) in a Primary Human Papillomavirus (HPV) Cervical Screening Programme Population with HPV Positive and Cytology Negative Smear Results

第三届中国卫星导航学术年会

作者： simon D P williams National Oceanography Centre LiverpoolUK

Non-tidal ocean loading （NTOL） is a crucial geophysical factor in resulting in the seasonal signals undermining geodetic GPS height time *** for the NTOL effects has thus been a critical prerequisite for estimating highly reliable secular rates of vertical crustal *** this study,we focus on whether a high temporal resolution model can benefit the correction for NTOL *** processed four years of GPS data from 26 stations around the North Sea of Europe and employed the Proudman Oceanographic Laboratory Storm Surge Model to correct the height *** and 12-hourly corrections were attempted *** generated 2-hourly heights to investigate the sub-daily signatures of NTOL effects,and also daily heights to assess the potential benefits of NTOL corrections of high temporal resolution to geophysical *** expected,hourly NTOL corrections lead to a reduction of the RMS of daily height residuals from 5.1 to 4.4 mm on average,and also a reduction of 21.2% for the integrated signal power over the seasonal to diurnal frequency ***,when applying the 12-hourly corrections instead,the RMS of daily height residuals is only slightly deteriorated by 0.01 mm on average and at most 0.06 mm,and the reduction of the integrated power for the seasonal to diurnal frequency band falls slightly to 20.4%.Therefore,we demonstrate that estimating the secular rates of vertical crustal motions will not benefit further from finer than 12-hourly NTOL corrections.

关键词： Non-tidal ocean loading GPS height time series Earth surface deformation Sea level change

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Open Journal of Obstetrics and Gynecology 2020年第7期10卷 902-908页

作者： simon G. williams Ayesha Anwar Sachinta G. Wijesiri Sangeetha Palaparthy Emma Winter Specialty Trainee in O&G South Tyneside and Sunderland NHS Foundation Trust Sunderland UK Consultant Obstetrician and Gynaecologist North Cumbria Integrated Care NHS Foundation Trust Carlisle UK Specialty Trainee in O&G County Durham and Darlington NHS Foundation Trust Durham UK Specialty Trainee in O&G Queen Elizabeth University Hospital Glasgow UK Specialty Doctor in Gynaecology and Colposcopy Services North Cumbria Integrated Care NHS Trust Carlisle UK

High-risk HPV is found in 99.7% of cervical cancers. The causative role of HPV in cervical cancer has led to the inclusion of HPV testing as part of cervical screening. A pilot of HPV testing as primary screening was commenced in 2013 at six pilot sites in England. North Cumbria Integrated Care (NCIC) NHS Foundation Trust took part in the pilot, in which women with an HPV-positive/cytology-negative result were recalled at 12 months. Women with HPV type 16/18 found at initial screening and persisting at 12 months in spite of negative cytology were referred to Colposcopy services at 12 months. Women with smear positive for hrHPV other than 16/18 types were recalled twice at 12 and 24 months before referral to colposcopy. Persistent hrHPV positive/cytology negative smear at 12 and 24 months initiated a colposcopy referral. Objective: To assess the prevalence of high grade CIN and invasive cancer in patients referred to colposcopy services at NCIC NHS Foundation Trust with hrHPV positive/cytology negative smears. Method: The study was conducted at NCIC NHS Foundation Trust between January 2015 and December 2017. Data was collected retrospectively from the colposcopy data base (INFOFLEX). All patients with HPV positive/cytology negative smears seen in colposcopy clinic during the study period were included. Patients with high grade CIN, cervical glandular intraepithelial neoplasia (CGIN) or invasive cancer were recorded. Results: 763 women were included in the study. A total of 50 (6.6%) women had high grade CIN, CGIN or invasive cancer. 40 of these 50 women (80%) were treated by large loop excision of the transformation zone (LLETZ). <

关键词： Cervical Screening Cervical Intraepithelial Neoplasia Cervical Cancer Human Papillomavirus Colposcopy

From Paleogeographic maps to Evolving Deep-time Digital Earth models

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Acta Geologica Sinica(English Edition) 2019年第S1期93卷 73-75页

作者： Sabin ZAHIROVIC Tristan SALLES Dietmar MüLLER Michael GURNIS CAO Wenchao Carmen BRAZ Lauren HARRINGTON Youseph IBRAHIM Rhiannon GARRETT simon williams CHEN Anqing HOU Mingcai James G.OGG Earth Byte Group School of GeosciencesThe Universiry of SydneyNSW 2006Australia Seismological Laboratory California Institute of TechnologyPasadenaCA91125USA International Civil Aviation Organisation United Nations Economic and Social CouncilMontrealcanada GHD SydneyNSW 2000Australia Northwest University Xi'anShaanxiChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(Chengdu University of Technology) Chengdu 610059China

Major advances in computational power,as well as community modelling workflows and an improvement in data availability,has revolutionized Earth sciences over the last *** data has been synthesized into flexible and open access plate tectonic and paleogeographic reconstructions using the open-source and cross-platform GPlates(***)software since 2008(Muller et al.,2018;Muller et al.,2008).

关键词： paleogeography tectonics Tethys GPlates Digital Earth

晚新元古代-早寒武世现代板块构造与现代地球系统的建立

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西北大学学报（自然科学版） 2021年第6期51卷 1007-1018页

作者：姚金龙赵国春韩以贵刘潜余珊 simon williams 何艳红李阳西北大学地质学系/大陆动力学国家重点实验室陕西西安710069 香港大学地球科学系中国香港

板块构造是维持岩石圈与表生系统之间物质与能量交换循环、保持地球生命力的一级动力学机制,但是板块构造在地球上并非与生俱来。板块构造的演化主要受控于地幔温度下降,并部分受俯冲带富水沉积物的影响。自太古代板块构造启动以来,其... 详细信息

板块构造是维持岩石圈与表生系统之间物质与能量交换循环、保持地球生命力的一级动力学机制,但是板块构造在地球上并非与生俱来。板块构造的演化主要受控于地幔温度下降,并部分受俯冲带富水沉积物的影响。自太古代板块构造启动以来,其经历了热俯冲、浅俯冲为特征的早期板块构造阶段、地球中年期以及冷俯冲、深俯冲为特征的现代板块构造阶段。新元古代晚期,特别是显生宙以来,地球上开始广泛出现低温/压(T/P)比的超高压变质岩;与此同时,同样受控于地幔温度的马里亚纳型大洋初始俯冲蛇绿岩开始出现于地球上了。这显示新元古代以来,由于地幔温度下降,板块构造体制进入深俯冲阶段。在此阶段,随着冈瓦纳古大陆的逐步聚合,在530~520 Ma,其周缘形成了俯冲带并发生了全球性的构造联动。此外,活动陆缘数量、温压比(T/P)、锆石Hf-O同位素演化趋势等都在早寒武世达到了峰值或低谷,表明早寒武世全球俯冲通量达到了一个新高度,俯冲作用达到全板块尺度。因此,启动于新元古代的现代板块构造,很可能在早寒武世才建立起来,在此之前,经历了构造转换阶段。板片的深俯冲造就了冈瓦纳古大陆聚合阶段史无前例、高耸入云的造山带,这些巨型山脉显著改变了地球的气候,为海洋输送了大量Fe,P等营养物质,促进了海洋初级生产力。此外,这一时期的高俯冲通量导致CO_(2)的构造排气量达到峰值。全球性构造过程显著提高了初级生产力,引发新元古代大气增氧事件(NOE),为早寒武世生命大爆发提供了必要条件。在此之后,地球表生气候环境逐渐接近现代地球,多门类高级生命繁盛,多圈层密切协同演化的现代地球系统逐渐建立。

关键词：现代板块构造现代地球系统冈瓦纳大陆造山作用俯冲带多圈层协同演化