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板块构造启动的时间和机制:理论和经验探索

科学通报 2007年第5期52卷 489-501页

作者： r. j. stern 唐俊(翻译) 牛耀龄(校对) Gcoscicnces Depar.ment University of Texas at Dallas Box 830688 Richardson TX 75083-0688 USA. 不详

板块构造是指位于对流地幔圈层之上的岩石圈的水平运动,主要由岩石圈在俯冲带的下沉作用所致.板块构造是一个典型的、非平衡复杂体系的自组系统(selfor.anizing,far.fr.m equilibr.um complex system,SOFFECS),其驱动力主要来自热边界层... 详细信息

板块构造是指位于对流地幔圈层之上的岩石圈的水平运动,主要由岩石圈在俯冲带的下沉作用所致.板块构造是一个典型的、非平衡复杂体系的自组系统(selfor.anizing,far.fr.m equilibr.um complex system,SOFFECS),其驱动力主要来自热边界层(岩石圈)的反向浮力,同时又受控于变形岩石圈与下覆粘性软流圈地幔的耗散作用.在太阳系内侧5个硅酸质行星中,板块构造仅发育于地球,这表明板块构造是硅酸质行星不太常见的一种热散逸方式.目前还不清楚这种构造活动和热散逸方式在地球上是从何时开始的.所有的硅酸质行星在形成初期可能都经历过一次短暂的岩浆海阶段.行星固结后,静止盖层模式是行星冷却的共同途径,即行星表面形成了一个不易活动的固化盖层,此时内部的热量只能通过拆沉作用、热点火山作用和岩浆浅部侵位等方式进行逃逸.由于地球早期温度较高,通过减压熔融形成的岩石圈结构不同于现代岩石圈,即地球早期岩石圈由厚的洋壳和薄的岩石圈地幔构成.这种岩石圈要产生反向浮力需要非常长的时间,因此地球早期即便有板块构造存在,其规模也比较零星.只有当地球冷却到一定程度,扩张中脊下部减压熔融形成薄的洋壳且大洋岩石圈只需几十个百万年就可以产生反向浮力时,才能形成与现今风格相似的、可持续性的板块构造.板块构造启动时间的认识最终取决于人们对相关地质记录(事件)的研究成果.板块构造的判别依据包括蛇绿岩、蓝片岩、超高压变质带、榴辉岩、被动大陆边缘、转换断层、指示克拉通陆块移动轨迹的古地磁研究以及岩浆岩地球化学和同位素构造判别等等.对地质记录的解释必须综合各方面的信息.本人认为现存的地质事件记录了地球构造随时间演化的过程,即太古代时期构造和岩浆活动剧烈,大约在1.9Ga时开始出现近似的板块构造,在新元古代才开始出现与现代相似的、可持续的、具有深俯冲和板片拖曳特性的板块构造.

关键词：板块构造俯冲前寒武纪地球动力学

俯冲带幼年期:来自始新世伊豆-小笠原-马里亚纳弧和侏罗纪加利福尼亚弧的实例

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海洋地质译丛 1993年第5期 75-81,F004页

作者： r. j. stern 金康

1 前言发生在会聚边缘的构造和岩浆过程对于地壳和地幔的演化是重要的。会聚边缘是岩基形成和许多成矿作用发生的场所,并在那儿形成陆壳和地壳受到分馏及残余体被再循环回到地幔。因此,越来越多的意义深远的文献专注于陆缘(安第斯型)和... 详细信息

1 前言发生在会聚边缘的构造和岩浆过程对于地壳和地幔的演化是重要的。会聚边缘是岩基形成和许多成矿作用发生的场所,并在那儿形成陆壳和地壳受到分馏及残余体被再循环回到地幔。因此,越来越多的意义深远的文献专注于陆缘(安第斯型)和洋内弧系的古代和现代火成产物。

关键词：俯冲带幼年期弧系加利福尼亚弧

Ear.y Cr.taceous subduction initiation beneath souther. Tibet caused the nor.hwar. flight of India

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Geoscience Fr.ntier. 2020年第4期11卷 1123-1131页

作者： Haoyu Hu r.ber. j.stern Geosciences Depar.ment University of Texas at DallasRichardsonTX75083-0688USA

Collision between the Indian and Eur.sian plates for.ed the ~2500 km long Yar.ung Zangbo Sutur. Zone and pr.duced the Himalaya mountains and Tibetan *** we offer.a new explanation for.tectonic events leading to this collision:that the nor.hwar. flight of India was caused by an Ear.y Cr.taceous episode of subduction initiation on the souther. mar.in of *** data for.ophiolites along the Yar.ung Zangbo Sutur. Zone show r.str.cted ages between 120 Ma and 130 Ma,and their.supr.-subduction zone affinities ar. best explained by seafloor.spr.ading in what became the for.ar. of a nor.h-dipping subduction zone on the souther. mar.in of *** subsequent evolution of this new subduction zone is r.vealed by integr.ting data for.ar.r.lated igneous r.cks of the Lhasa ter.ane and Xigaze for.ar. basin *** slab pull fr.m this new subduction zone tr.gger.d the r.fting of India fr.m East Gondwana in Ear.y Cr.taceous time and pulled it nor.hwar. to collide with Tibet in Ear.y Paleogene time.

关键词： Cr.taceous nor.hwar. subduction

The Or.sir.an(1800–2050 Ma)plate tectonic episode:Key for.r.constr.cting the Pr.ter.zoic tectonic r.cor.

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Geoscience Fr.ntier. 2023年第3期14卷 1-9页

作者： r.ber. j.stern Geosciences Dept. U Texas at DallasRichardsonTX 75083-0688United States

Eight lines of evidence indicate that the Or.sir.an Per.od in mid-Paleopr.ter.zoic time was char.cter.zed by plate tectonics:ophiolites,low T/P metamor.hism including eclogites,passive mar.in for.ation,tall mountains,paleomagnetic constr.ints,or. deposits,abundant S-type gr.nites,and seismic images of paleo-subduction *** plate tectonic episode occur.ed about 1 billion year. ear.ier.than the pr.sent plate tectonic episode began in Neopr.ter.zoic *** two plate tectonic episodes br.cket the‘Bor.ng Billion’,which may have been a pr.tr.cted single lid tectonic episode that began when the super.ontinent Nuna or.Columbia *** of multiple lines of evidence for.Or.sir.an plate tectonics demonstr.tes that Ear.h’s tectonic style can be r.constr.cted with some confidence back to at least Ear.y Paleopr.ter.zoic time,and thus the absence of compelling evidence for.Mesopr.ter.zoic plate tectonics is not obvious due to poor.pr.ser.ation.A tectono-magmatic lull2.3 Ga suggests an ear.ier.episode of single lid *** for.two episodes of plate tectonics and two episodes of single lid tectonics indicates that Ear.h switched between single lid and plate tectonics multiple times dur.ng the last 2.4 Ga.

关键词： Plate tectonics Single lid tectonics Ur.y r.tio Paleopr.ter.zoic

Is plate tectonics needed to evolve technological species on exoplanets?

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Geoscience Fr.ntier. 2016年第4期7卷 573-580页

作者： r.ber. j.stern Geoscience Depar.ment University of Texas at Dallas

As we continue sear.hing for.exoplanets, we wonder.if life and technological species capable of communicating with us exists on any of them. As geoscientists, we can also wonder.how impor.ant is the pr.sence or.absence of plate tectonics for.the evolution of technological species. This essay consider. this question, focusing on tectonically active r.clw （silicate） planets, like Ear.h, Venus, and Mar.. The development of technological species on Ear.h pr.vides key insights for.under.tanding evolution on exoplanets, including the likely r.le that plate tectonics may play. An Ear.h-sized silicate planet is likely to exper.ence sever.l tectonic styles over.its lifetime, as it cools and its lithospher. thickens, str.ngthens, and becomes denser. These include magma ocean, var.ous styles of stagnant lid, and per.aps plate tectonics. Abundant liquid water.favor. both life and plate tectonics. Ocean is r.quir.d for.ear.y evolution of diver.e single-celled or.anisms, then colonies of cells which specialized fur.her.to for. guts, ap- pendages, and sensor. or.anisms up to the complexity of fish （centr.l ner.ous system, appendages, eyes）. Lar.e expanses of dr. land also begin in the ocean, today pr.duced above subduction zones in j.venile ar.s and by their.coalescence to for. continents, although it is not clear.that plate tectonics was r.quir.d to cr.ate continental cr.st on Ear.h. Dr. land of continents is r.quir.d for.fur.her.evolution of technological species, wher. modification of appendages for.gr.sping and manipulating, and impr.ve- ment of eyes and centr.l ner.ous system could be per.ected. These bioassets allowed intelligent cr.a- tur.s to examine the night sky and wonder. the beginning of abstr.ct thinking, including r.ligion and science. Technology ar.ses fr.m the exigencies of daily living such as tool-making, agr.cultur., clothing, and weapons, but the pace of innovation acceler.tes once it is allied with science. Finally, the impor.ance of plate tectonics for.devel

关键词： Plate tectonics Exoplanets Planetar. science Intelligent life

Ophiolites:Identification and tectonic significance in space and time

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Geoscience Fr.ntier. 2023年第6期14卷 380-385页

作者： Kent C.Condie r.ber. j.stern Depar.ment of Ear.h&Envir.nmental Science New Mexico Institute of Mining and TechnologySocorroNM 87801USA Geosciences Depar.ment University of Texas at DallasRichardsonTX 75080USA

Ophiolites ar. fr.gments of oceanic lithospher. that ar. pr.duced at spr.ading center. at ocean r.dges,back ar. basins,or.for.ar.s dur.ng subduction initiation,and ar. key indicator. of plate *** it is widely agr.ed that ophiolites ar. r.mnants of oceanic cr.st and associated depleted mantle pr.ser.ed in or.gens,the r.cognition of ophiolites and their.tectonic significance is still a topic of discussion and *** pr.pose that ophiolites can be r.cognized in the geologic r.cor. by some combination of genetically r.lated pillow basalt,layer.d gabbr.,sheeted dykes,podifor. chr.mite,har.bur.ite or.and *** igneous r.cks have either.ocean-r.dge basalt or.immatur. oceanic ar. basalt chemical *** a scor.ng system of 1–11 for.ophiolite confidence level,scor.s of8 ar. consider.d confident,6–8 pr.bable,andr.unlikely *** ophiolites with scor.s6 ar.r. of 8)is the Zunhua ophiolite in eastern China at 2550 Ma,and the oldest well documented sheeted dykes occur.in the j.r.ua and Pur.uniq ophiolites at 2000–1950 *** do not become geogr.phically widespr.ad until after.900 Ma,and most ophiolites of all ages for.ed in a for.ar.(subduction initiation)tectonic *** ophiolite pr.duction r.quir.s plate tectonics,subduction must have begun at least locally by 2700 Ma but did not become widespr.ad until after.2000 *** abundance of ophiolites after.900 Ma may r.flect better.pr.ser.ation of subduction-r.lated ophiolites,or.to an incr.asing global networ. of inter.onnected *** fr.quency peaks in the geologic r.cor. par.ially r.flect geogr.phic r.gions wher. ophiolites have been extensively studied r.ther.than monitor.ng the pr.duction r.te of ophiolites,but the scar.ity of>900 Ma ophiolites is pr.bably r.al.

关键词： Ophiolite Plate tectonics Subduction initiation For.ar. Ocean r.dge Tectonic setting Super.ontinent

Stagnant lid tectonics:Per.pectives fr.m silicate planets,dwar. planets, lar.e moons,and lar.e aster.ids

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Geoscience Fr.ntier. 2018年第1期9卷 103-119页

作者： r.ber. j.stern Tar.s Ger.a Paul j.Tackley Geosciences Depar.ment University of Texas at Dallas Depar.ment of Ear.h Sciences ETH-Zurich

To better.under.tand Ear.h's pr.sent tectonic style-plate tectonics—and how it may have evolved fr.m single plate(stagnant lid) tectonics, it is instr.ctive to consider.how common it is among similar.bodies in the Solar.System. Plate tectonics is a style of convection for.an active planetoid wher. lid fr.gment(plate) motions r.flect sinking of dense lithospher. in subduction zones, causing upwelling of asthenospher. at diver.ent plate boundar.es and accompanied by focused upwellings, or.mantle plumes;any other.tectonic style is usefully called "stagnant lid" or."fr.gmented lid". In 2015 humanity completed a 50+ year.effor. to sur.ey the 30 lar.est planets, aster.ids, satellites, and inner.Kuiper.Belt obj.cts,which we infor.ally call "planetoids" and use especially images of these bodies to infer.their.tectonic activity. The four.lar.est planetoids ar. enveloped in gas and ice(j.piter. Satur., Ur.nus, and Neptune)and ar. not consider.d. The other.26 planetoids r.nge in mass over.5 or.er. of magnitude and in diameter.over.2 or.er. of magnitude, fr.m massive Ear.h down to tiny Pr.teus; these bodies also r.nge widely in density, fr.m 1000 to 5500 kg/m^3. A gap separ.tes 8 silicate planetoids with ρ = 3000 kg/m^3 or.gr.ater.fr.m 20 icy planetoids(including the gaseous and icy giant planets) with ρ = 2200 kg/m^3 or.less. We define the "Tectonic Activity Index"(TAI), scor.ng each body fr.m 0 to 3 based on evidence for.r.cent volcanism, defor.ation, and r.sur.acing(infer.ed fr.m impact cr.ter.density). Nine planetoids with TAI = 2 or.gr.ater.ar. inter.r.ted to be tectonically and convectively active wher.as 17 with TAI r. infer.ed to be tectonically dead. We fur.her.infer.that active planetoids have lithospher.s or.icy shells over.ying asthenospher. or.water.weak ice. TAI of silicate(r.cky) planetoids positively cor.elates with their.infer.ed r.yleigh number. We conclude that some type of stagnant lid tectonics is the dominant mode of heat loss and that plate tectonics

关键词： Stagnant lid Solar system Plate tectonics Planets Moons

Envir.nmental engineer.ng of tr.nsition metal dichalcogenide optoelectr.nics

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Fr.ntier. of physics 2018年第4期13卷 21-52页

作者： Tr.vor.LaMountain Er.k j. Lenfer.nk Yen-j.ng Chen Teodor.K. Stanev Nathaniel P. stern Depar.ment of Physics and Astr.nomy Northwestern University Evanston Illinois 60208 USA

The explosion of inter.st in two-dimensional van der.Waals mater.als has been in many ways dr.ven by their.layer.d geometr.. This featur. makes possible numer.us avenues for.assembling and ma- nipulating the optical and electr.nic pr.per.ies of these mater.als. In the specific case of monolayer.tr.nsition metal dichalcogenide semiconductor., the dir.ct band gap combined with the flexibility for.manipulation of layer. has made this class of mater.als pr.mising for.optoelectr.nics. Her., we r.view the pr.per.ies of these layer.d mater.als and the var.ous means of engineer.ng these pr.per.ies for.optoeleetr.nics. We summar.ze appr.aches for.contr.l that modify their.str.ctur.l and chemical en- vir.nment, and we give par.icular.detail on the integr.tion of these mater.als into engineer.d optical fields to contr.l their.optical char.cter.stics. This combination of contr.llability fr.m their.layer.d sur.ace str.ctur. and photonic envir.nment pr.vide an expansive landscape for.novel optoelectr.nic phenomena.

关键词： tr.nsition metal dichalcogenides optoelectr.nics van der.Waals mater.als heter.str.ctur.s excitons

Cor.elation of endoscopic disease sever.ty with pediatr.c ulcer.tive colitis activity index scor. in childr.n and young adults with ulcer.tive colitis

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Wor.d j.ur.al of Gastr.enter.logy 2017年第18期23卷 3322-3329页

作者： Basavar.j.Ker.r.Heather.j.Litman j.lia Bender.stern Sar.h Weber.j.nifer.r.Lightdale Paul A r.fo Athos Bousvar.s Pediatr.c Gastr.enter.logy Hasbro Children's Hospital Cor.ona LLC Southborough Inflammator. Bowel Disease Center Children's Hospital Boston Division of Pediatr.c Gastr.enter.logy UMass Memorial Medical CenterUniversity Campus Worcester

To investigate of pediatr.c ulcer.tive colitis activity index (PUCAI) in ulcer.tive colitis cor.elate with mucosal inflammation and endoscopic assessment of disease activity (Mayo endoscopic scor.).METHODSWe r.viewed char.s fr.m ulcer.tive colitis patients who had under.one both colonoscopy over.3 year.. Clinical assessment of disease sever.ty within 35 d (either.befor. or.after. the colonoscopy wer. included. Patients wer. excluded if they had significant ther.peutic inter.entions (such as the star. of cor.icoster.ids or.immunosuppr.ssive agents) between the colonoscopy and the clinical assessment. Mayo endoscopic scor. of the r.ctum and sigmoid wer. done by two gastr.enter.logists. Inter.obser.er.var.ability in Mayo scor. was *** identified 99 patients (53% female, 74% pancolitis) that met inclusion cr.ter.a. The indications for.colonoscopy included ongoing disease activity (62%), consider.tion of medication change (10%), assessment of medication efficacy (14%), and cancer.scr.ening (14%). Based on PUCAI scor.s, 33% of patients wer. in r.mission, 39% had mild disease, 23% had moder.te disease, and 4% had sever. disease. Ther. was “moder.te-substantial” agr.ement between the two r.viewer. in assessing r.ctal Mayo scor.s (kappa = 0.54, 95%CI: 0.41-0.68).CONCLUSIONEndoscopic disease sever.ty (Mayo scor.) assessed by r.viewing photogr.phs of pediatr.c colonoscopy has moder.te inter.r.ter.r.liability, and agr.ement was less r.bust in assessing patients with mild disease activity. Endoscopic disease sever.ty gener.lly cor.elates with clinical disease sever.ty as measur.d by PUCAI scor.. However. childr.n with inflamed colons can have significant var.ation in their.r.por.ed clinical symptoms. Thus, assessment of both clinical symptoms and endoscopic disease sever.ty may be r.quir.d in futur. clinical studies.

关键词： Ulcer.tive colitis Pediatr.c ulcer.tive colitis activity index Mayo scor.