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William R. Farrand 《第四纪研究》1991,11(2):178-189
本文详尽地考证了第四纪、更新世和全新世等几个地层术语的来历及这些术语在使用过程中的词义演变,并讨论了相关的问题。通过这些历史的回顾和问题的讨论,可概括地了解150多年来的地质思想的演变。 相似文献
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Frederik J. Hilgen 《Earth》2010,98(1-2):65-80
Today astronomical tuning is widely accepted as numerical dating method after having revolutionised the age calibration of the geological archive and time scale over the last decades. However, its origin is not well known and tracing its roots is important especially from a science historic perspective.Astronomical tuning developed in consequence of the astronomical theory of the ice ages and was repeatedly used in the second half of the 19th century before the invention of radio-isotopic dating. Building upon earlier ideas of Joseph Adhémar, James Croll started to formulate his astronomical theory of the ice ages in 1864 according to which precession controlled ice ages occur alternatingly on both hemispheres at times of maximum eccentricity of the Earth's orbit. The publication of these ideas compelled Charles Lyell to revise his Principles of Geology and add Croll's theory, thus providing an alternative to his own geographical cause of the ice ages. Both Croll and Lyell initially tuned the last glacial epoch to the prominent eccentricity maximum 850,000 yr ago. This age was used as starting point by Lyell to calculate an age of 240 million years for the beginning of the Cambrium. But Croll soon revised the tuning to a much younger less prominent eccentricity maximum between 240,000 and 80,000 yr ago. In addition he tuned older glacial deposits of late Miocene and Eocene ages to eccentricity maxima around 800,000 and 2,800,000 yr ago. Archibald and James Geikie were the first to recognize interglacials during the last glacial epoch, as predicted by Croll's theory, and attempted to tune them to precession. Soon after Frank Taylor linked a series of 15 end-moraines left behind by the retreating ice sheet to precession to arrive at a possible age of 300,000 yr for the maximum glaciation.In a classic paper, Axel Blytt (1876) explained the scattered distribution of plant groups in Norway to precession induced alternating rainy and dry periods as recorded by the layering in Holocene peat bogs. He specifically linked the exceptionally wet Atlantic period to the prolonged precession minimum at 33,300 yr ago and further related basic stratigraphic alternations to precession induced climate change in general. Such a linkage was also proposed by Grove Karl Gilbert for cyclic alternations in the marine Cretaceous of North America. Extrapolating sedimentation rates, he arrived at an astronomical duration for part of the Cretaceous that was roughly as long as the final estimate of William Thomson for the age of the Earth. Assuming that orbital parameters directly affect sea level, Karl Mayer-Eymar and Blytt correlated the well known succession of Tertiary stages to precession and eccentricity, respectively. Remarkably, Blytt, like Croll before him, used very long-period cycles in eccentricity to establish and validate his tuning.Understandably these studies in the second half of the 19th century were largely deductive in nature and proved partly incorrect later. Nevertheless, this fascinating period marks a crucial phase in the development of the astronomical theory of the ice ages and climate, and in astronomical dating. It preceded the final inductive phase, which started with the recovery of deep-sea cores in 1947 and led to a spectacular revival of the astronomical theory, by a century. The first half of the 20th century can best be regarded as an intermediate phase, despite the significant progress made in both theoretical aspects and tuning. 相似文献
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E.M. Rutledge M.J. Guccione H.W. Markewich D.A. Wysocki L.B. Ward 《Engineering Geology》1996,45(1-4):167-183
Loesses of the Lower Mississippi Valley (LMV) are world-famous. Sir Charles Lyell (1847), Hilgard (1860), Stafford (1869), Call (1891) and Mabry (1898), thought the LMV loess was a single water deposit although “double submergence” was noted by Call (1891) and Salisbury (1891). Shimek (1902) and Emerson (1918) recognized LMV loess as a wind deposit which came from the valley. Although wind-deposited loess gained wide acceptance, Russell (1944a) published his controversial theory of “loessification” which entailed weathering of backswamp deposits, downslope movement and recharge by carbonates to form loess. Wascher et al. (1947) identified three LMV loesses, mapped distributions and strongly supported eolian deposition. Leighton and Willman (1950), identified four loesses and supported eolian deposition as did Krinitzsky and Turnbull (1967) and Snowden and Priddy (1968), but Krinitzky and Turnbull questioned the deepest loess. Daniels and Young (1968) and Touchet and Daniels (1970) studied the distribution of loesses in south-central Louisiana. West et al. (1980) and Rutledge et al. (1985) studied the source areas and wind directions which deposited the loesses on and adjoining Crowley's Ridge. B.J. Miller and co-workers (Miller et al., 1985, 1986, Miller and Alford, 1985) proposed that the Loveland Silt was Early Wisconsin rather than Illinoian age and advanced the name Sicily Island loess. They proposed the underlying loess was Illinoian and advanced the name Crowley's Ridge. We termed the loesses, from the surface downward, Peoria Loess, Roxana Silt, Loveland/Sicily Island loess, Crowley's Ridge Loess and Marianna loess. Researchers agree that the surfical Peoria Loess is Late Wisconsin and the Roxana Silt is Late to Middle Wisconsin, but little agreement exists on the age of the older loesses. Pye and Johnson (1988) proposed Early Wisconsin for the Loveland/Sicily Island. McKay and Follmer (1985) suggested this loess correlated with a loess under Illinoian till. Clark et al. (1989) agreed on Crowley's Ridge, but suggested the Loveland/Sicily Island loess on Sicily Island was older. Mirecki and Miller (1994) and Millard and Maat (1994) suggested an Illinoian age for the Loveland/Sicily Island loess. Miller and co-workers suggested, as did Pye and Johnson (1988), an Illinoian age for the Crowley's Ridge loess. McKay and Follmer (1985) suggested it correlated with a loess under “Kansan” till. Stratigraphy indicates the Marianna is the older of the five loesses.
Researchers identified loess on both the east and west side of the LMV as well as on higher terraces within the valley. Many researchers assumed unaltered loesses were commonly yellowish brown, and silts or silt loams (West et al., 1980; Miller et al., 1986). The nonclay fraction of unweathered LMV loesses was dominated by quartz followed * Corresponding author. by carbonates, mainly dolomites, followed by feldspars, and micas. Clays were dominated by montmorillonite followed by micaceous minerals, kaolinite and vermiculite (Miller et al., 1986). Soils in the Crowley's Ridge loess are most developed, followed by the soils in the Loveland/Sicily Island which are more developed than the modern soils in the Peoria Loess. Soils in the Roxana and Marianna loesses are least developed and the Farmdale Soil of the Roxana is the weaker of the two (Miller et al., 1986). There is certainly overlapping range in the degree of soil development in the various loesses. 相似文献
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Hermann Abich was born in 1806 in Berlin and died in 1886 in Graz. He grew up in a wealthy family which had friendly relations with famous scientists like Alexander von Humboldt, Leopold von Buch or Carl Ritter. After his studies in Heidelberg and Berlin he turned to extended fieldwork at the volcanoes of Italy. In 1833–1834 he published excellent petrological/chemical results and got soon a good scientific reputation. Thus he was nominated as Professor for Geology and Mineralogy of the prestigious Russian University in Dorpat (now Tartu, Esthonia) in 1842. In 1844 he was sent to Armenia by the Russian authorities. For the next three decades his fieldwork with about 190 publications was concentrated on the Great and Lesser Caucasus. This was a period of Russian expansion to the South with long-lasting regional fights. But he enjoyed the support of powerful governors. He was an indefatigable and enthusiastic explorer and a precise observer and designer. His interests covered many fields: morphology, glaciology, structural geology, volcanology with Thermal Springs, mineral resources from hydrocarbons, coal, salt to ores, stratigraphy and paleontology as a base for geological maps. But he also gave advice for practical problems, and he was active in meteorology, botany and archaeology. Alltogether he became “the Father of Caucasus Geology”. The following sketch stresses only on three aspects of his activities. He was one of the first pioneers in hydrocarbon exploration, especially around the anticlines with the mud volcanoes near Baku. In many respects, however, his fundamental ideas were erronous. He explained the structure of the Great Caucasus by the traditional theories of Leopold von Buch and Elie de Beaumont. The Caucasus anticline “was elevated by forces acting from beneath”. Following them he tried to discover regularities in the strike of mountain chains. Similarily he treated volcanism like Alexander von Humboldt and Leopold von Buch with their two groups of phenomena: voluminous, mostly basaltic “elevation craters” versus isolated, mostly trachytic and relatively small cones of “true volcanoes”. In spite of the isolation of the Caucasus region he had cultivated continuously contacts with leading geologists in Europe and was honoured by many institutions. He left Russia in 1876 for Vienna planning to write there the final monograph volumes about his investigations but he died before he could complete them. 相似文献
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C. Perkins 《Mineralium Deposita》1996,31(1-2):71-83
The 40Ar/39Ar dating of alteration muscovite from the Rosebery Zn-Pb-Cu and Mount Lyell Cu deposits, Tasmania, Australia, has determined a succession of deformation events which occurred from 400-378 Ma, and comprises the Devonian Tabberabberan Orogeny. The dates from Rosebery range from 400-390 Ma, are a minimum age for mineralization, indicate the time of deformation, and provide a maximum age limit for granitoid emplacement in the vicinity of the deposit. The ages from the Mount Lyell field range from 400-378 Ma, are a minimum for mineralization, and date cleavage development. The North Lyell Cu mineralization, which was probably broadly coeval with deformation, may have formed at 400 Ma. All pre-Devonian alteration micas in the Rosebery and Mount Lyell areas have been recrystallized or reset. The Tabberabberan deformation in western Tasmania was broadly contemporaneous with widespread crustal shortening in southeastern Australia, as established from the dating of alteration minerals associated with deformation-related precious and base metal deposits. 相似文献
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Pyrite composition and ore genesis in the Prince Lyell copper deposit, Mt Lyell mineral field, western Tasmania, Australia 总被引：3，自引：0，他引：3
Oliver L. Raymond 《Ore Geology Reviews》1996,10(3-6)
The Prince Lyell copper-gold-silver deposit occurs in the late Cambrian Mt Read Volcanics, at Queenstown, Tasmania. Steeply plunging, broadly conformable lenses of disseminated and stringer pyrite-chalcopyrite mineralisation occur in quartz-sericite-chlorite rocks derived from intense alteration of predominantly felsic lavas and volcaniclastic rocks. Middle Devonian deformation has substantially modified primary sulphide textures.Although extensively fractured, pyrite grains in the ore have retained their original pre-deformation internal structure and chemistry which are revealed by etching and electron microprobe analysis. Earliest sulphide mineralisation produced oscillatory zoned, cobalt-rich pyrite (Pyrite I), coeval with chalcopyrite mineralisation. Cobalt-rich pyrite is commonly associated with Cambrian volcanic rocks in western Tasmania and suggests a volcanogenic origin for the ore fluids at Prince Lyell. Pyrite I was corroded by later hydrothermal fluids and reprecipitated as unzoned, trace element-poor pyrite (Pyrite II), commonly as overgrowths on Pyrite I cores. Minor amounts of a second cobalt-rich pyrite (Pyrite III) occurs with Pyrite II in composite pyrite overgrowths. Sulphur isotope ratios from all pyrite generations fall within a small range (3 to 11‰). In situ isotopic analyses showed no consistent δ34S variation between the various pyrite generations, suggesting recycling of sulphur derived from a single Cambrian volcanogenic source.Hematite alteration, derived from oxidised fluids possibly from the adjacent hematitic Owen Conglomerate, occurs in the structural footwall volcanics and the Great Lyell fault zone. Hematite inclusions in Pyrite II and III indicate that these pyrite generations occurred after or during deposition of the conglomerate. It is postulated that Pyrite II and III were deposited during waning volcanism, contemporaneous with Owen Conglomerate sedimentation in the late Cambrian or early Ordovician. The Great Lyell fault would have acted as a growth fault margin between a terrestrial basin, filling rapidly from the east, and the volcanic terrane to the west. The scenario raises the possibility that the concentration of mineral deposits and hematitic alteration along the Great Lyell fault resulted from the subsurface interaction of reduced volcanogenic fluids and oxidised basin waters along the growth fault contact. 相似文献
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洛川黄土序列时间标尺的初步建立 总被引：10，自引：0，他引：10
对厚１４０ｍ的洛川坡头黄土剖面黄土层以５ｃｍ，古土壤层以３ｃｍ系统采样，全部样品进行了室内磁化率测量。以黄土序列磁化率变化作为古季风气候变化的代用指标，根据第四纪冰期的Ｍｉｌａｎｋｏｖｉｔｃｈ理论，利用轨道调缠绵的方法初步建立了洛川黄支的时间标尺。通过古地磁场倒转时间的检验以及与宝鸡黄土序列时间标尺对比，表明本文所论述的时间标尺适用于该地区古环境演化的研究。 相似文献
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Joggins is a famous fossil locality in Nova Scotia, Canada. Hewn by some of the world's highest tides on the Bay of Fundy, these crumbling cliffs shed light on the life and environments of the Carboniferous Coal Age, 315 million years ago. The site has been a magnet for geologists since the early nineteenth century. Charles Lyell described it as the world's best coal‐bearing section and together with his colleague, William Dawson, reported amazing fossil forests and a rich terrestrial fauna. Since that golden age, the rate of new fossil discoveries has hardly diminished and in recognition of its importance, the Joggins Fossil Cliffs was awarded UNESCO World Heritage Status in 2008. Even after many years of study, it remains a tremendous thrill for us to explore this ‘classic locality’ in far‐flung Nova Scotia. Each winter storm, rock fall, and tide brings with it the tantalizing possibility of new fossils and new scientific insights. In this article we share something of our excitement for Joggins and provide an up to date field guide for those wishing to unlock its secrets. 相似文献
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Landslides triggered by the 1949 Khait earthquake, Tajikistan, and associated loss of life 总被引：3，自引：0，他引：3
Stephen G. Evans Nicholas J. Roberts Anatoli Ischuk Keith B. Delaney Galina S. Morozova Olga Tutubalina 《Engineering Geology》2009,109(3-4):195-212
Earthquake-triggered landslides are a major geological hazard in Central Asia. In July 1949, the M7.4 Khait earthquake triggered many hundreds of landslides in a mountainous region near the southern limit of the Tien Shan Mountains, central Tajikistan. These landslides involved widespread rock-slope failure as well as large numbers of flowslides in loess that mantles the steep slopes of the region. In the Yasman valley hundreds of loess landslides coalesced to form a massive loess flow (est. vol. 245 Mm3) that travelled up to 20 km on a slope of only 2°. In an adjacent valley, the Khait landslide involved transformation of an earthquake-triggered rockslide into a very rapid flow by the entrainment of saturated loess into its movement. It travelled 7.41 km over a vertical distance of 1421 m with an estimated average velocity of ~30 m/s. We estimate its volume as 75 Mm3, an order of magnitude less that previously published estimates. The Khait landslide was simulated using DAN. The number of casualties due to earthquake-triggered landslides in the epicentral region was considerable. Approximately 4000 people were killed in the Yasman valley loess flow as 20 villages (kishlaks) were overwhelmed. In the Khait landslide alone we estimate ca. 800 people lost their lives when the villages of Khait and Khisorak were overrun by rapidly moving debris. Our data indicates that a total of approximately 7200 people were killed by earthquake-triggered landslides in the epicentral region of the Khait earthquake and that, in terms of loss of life, the 1949 Yasman valley loess flow was one of the most destructive landslides in recent history. 相似文献
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诱发滑坡的地下水流系统响应历史与趋势——以甘肃黑方台灌区为例 总被引：1，自引：0，他引：1
灌溉的地下水系统响应是黑方台地区灌溉诱发地质灾害研究的基础.黑方台台塬自上而下由黄土、砂砾石和基岩3个含水岩组构成.以对斜坡稳定性影响最大的黄土含水系统为研究对象,分析了灌溉前后水均衡变化,采用数值模拟的方法恢复了引水灌溉引起的地下水流系统演化过程,对不同灌溉量下地下水流系统发展趋势进行了预测.结果表明,黑方台地区长期大量引水灌溉打破了地下水均衡,改变了地下水系统的天然状态,使地下水的分布及其水流系统发生了很大变化,中心部位地下水位44年间上升了至少20m,减少灌溉量至350× 104m3/a地下水位将呈下降趋势.研究成果可为黑方台滑坡地质灾害综合治理提供科学依据. 相似文献
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Dieter Jkel 《第四纪研究》2005,25(4):409-431
斐迪南·冯·李希霍芬出生于1833年。少年时的教育和生活环境使他对地质学产生了兴趣。当他还是小孩子的时候,就随父母游历了家乡的许多地方,并且利用暑假到阿尔卑斯去旅行。在柏林学习地质学的时候,就显示出他宽厚的知识基础,他很快就意识到对他而言,未来工作的目标就是成为一个科学家。1859年,为了获得财政支持进行欧洲以外地区的研究,李希霍芬申请参加了普鲁士政府向东亚派遣的一支探险队,开始了他最初对中国地质的研究。1862年当探险队的成员开始返回柏林,他独自到了上海开始他自己在中国的研究工作。只是由于太平天国起义,他的计划没能立即实现。1868年新年前夕,他和他的朋友对全球地质勘探的状况做了一个回顾,认为中国无论在科学上,还是在应用上都是最有研究价值的国家之一。于是他选择了中国作为他进行地质研究的对象。在参考大量文献的基础上,他制定了详细的研究方向和工作方法。李希霍芬希望建立一个系统的中国地质学的基础。他认为野外工作是第一位的。除了对可开采的矿床进行了估计,他还特别注意了中国煤炭沉积的储量和产量。在1868到1872年期间,他在中国先后进行了7次旅行。他是第一位对中国地质从基础上进行研究的外国地质学家。旅行的资金有一部分是来自加利福尼亚银行和上海商业会馆。他提交了一份地区经济信息的报告,这个报告包括了中国的交通、贸易路线,煤矿的形成、品位和储量、可采性以及在世界市场上的竞争力等。他重要的科学文献是关于经济、运输和人口地理学。从他的著作《中国》我们可以看出,他对于“丝绸之路”的命名是在汉学家、古典文献学家以及地图学家共同合作研究之前。在综合大量的文献后,他在地图上详细地标注了“丝绸之路”,并且讨论了汉朝及其以后历史时期内中国境内主要的贸易路线。由于丝绸一直都是重要的贸易商品,因此他把这条贸易路线称之为“丝绸之路”。对于社会、经济问题与地质问题的综合认识,使他同时又成为一个地理学家。李希霍芬和德国的地图工作者一起开创了一种新的地形的描绘方法,并且修正了当时的中国地图,使中国地图有了更为详尽的内容。对比当时在中国出版的地图,他们绘制的地图在很多方面是全新的,如他们采用图解法(graphicpresentationsofmontains)来代表山脉和其他的地形形态特征。在地质学领域,他绘制了中国地质图,及《中国地图集》中的地形图,连同后来出版的4卷《中国》书稿中大量的横断面和地层剖面,奠定了中国乃至东亚的地质学基础。但是他从来没有把制图作为他旅行的一个主要目的。对他来说,制图只是作为来证实他的野外观察的一个方法,以尽可能正确地体现出地貌的基本特征。李希霍芬到中国旅行的最主要的目的是研究中国地质。他是第一个把中国地质按着现代组成物的分布、序列,发展成为一个系统。可以认为,他是把中国地质学发展成为一门科学的创始人。古生物学和地层学的知识使他很快就认识到了中国地质结构的原理。他的综合知识使他可以在地图上系统地标绘出他所观察到的现象。他的主要成果集中体现在《中国地图集》中的27张地质图,《中国》书稿中另外14张地质图以及大量的剖面图。另外矿产资源也是他研究的主要的内容。他不仅研究了煤炭资源,同时也经常记录贵金属矿产资源。他是最早注意到中国黄土具有风成特征的地质学家。他在研究黄土剖面时,注意到大部分没有层理的沉积物都保存有大量的陆生软体动物的壳。由此,他得出与前人相反的结论,认为黄土不是湖相沉积物,而是风成沉积物。并以北美大草原所见到的草将粉尘固定的过程作为他风成假设的证据。他认为黄土沉积是草原环境下形成的,当时的植被是草原。并且认识到粉尘来源于西部和北部的中亚的沙漠地区。他只是没能将冰期、间冰期的粉尘沉积加以区分。他研究的另一个科学领域是地貌学。在地貌学中他是最先描述一些地表变化过程的先驱者之一。正如他一直意识到的自然与人类活动的相互关系一样,他同样将地球生态系统看作是地质结构、地貌过程、与气候有关的生态环境和人类活动所组成的一个复合体。他是最早萌生地球系统的科学思想的科学家。李希霍芬对中国的研究起初并没有得到人们的重视。直到他的《中国》出版以后,他对中国地质学和地理学的影响才明显起来:他的著作和地图很快就传入中国,在学术界被广泛地阅读和讨论;他的书是地质学和地理学专业的基础教材。不仅在中国,在世界范围内,他的发现也得到了认可,并获得了很高的评价。19世纪末,世界上没有哪个科学家像他那样了解中国和东亚。他也从一个地质学家成为一个跨越多个学科的大科学家,他的影响在他的那个时代体现在科学领域的很多学科之中。李希霍芬在中国现在仍然有很高的赞誉。他的方法学的研究以及他的《探险家指南》,对于年轻的地质科学工作者,仍然具有指导意义。他的地球系统科学的思想对当前土地退化、生态不平衡等环境问题的解决仍然起着指导性作用。 相似文献
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Michael B. Roberts 《Proceedings of the Geologists' Association. Geologists' Association》2012,123(4):649-662
The concept of a former Ice Age was introduced to Britain by Agassiz, first, through Buckland in 1838 and then by his tour of Britain in 1840. The reception was mixed due to the Iceberg theory, which was held by Darwin, Lyell and Murchison and others. After 1840, Murchison looked for a compromise between Glaciers and Icebergs and this came in the work of Bowman and Buckland in 1841 and Darwin during 1842 in Snowdonia and the Marches. There were three geologists visiting Wales, all familiar with glaciation; Bowman failed to find any glaciation and Buckland and Darwin, who identified both alpine-glacier and “ice-berg” glaciation and reinterpreted their previous work. Thus both a Catastrophist and a Uniformitarian came to similar conclusions, but it was several decades before a consensus was found, which was delayed by Darwin's emphasis on submergence. 相似文献
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Fossiliferous Cambrian limestone from within the mt read volcanics,mt lyell mine area,Tasmania 总被引：1，自引：1，他引：0
J. B. Jago K. O. Reid P. G. Quilty G. R. Green B. Daily 《Australian Journal of Earth Sciences》2013,60(3):379-382
In the Mt Lyell area limestone conformably underlying unmineralized Mt Read Volcanics and unconformably overlying mineralized Mt Read Volcanics contains fossils of late Middle Cambrian or early Upper Cambrian age. This suggests an upper limit of late Middle Cambrian or early Upper Cambrian for the mineralization in the Mt Lyell area. The view of Gee et al. (1970) that the Mt Read Volcanics and the fossiliferous Cambrian sequences of western Tasmania are at least partly contemporaneous is confirmed. 相似文献
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甘肃永靖黑方台4·29罗家坡黄土滑坡的特征 总被引：2，自引：1，他引：1
2015年4月29日上午,甘肃省永靖县盐锅峡镇黑方台滑坡高频发区的党川村罗家坡同一斜坡处连续发生了2次大规模黄土滑坡,总体积约65×10~4m~3,最大滑距630 m,摧毁14户居民房屋和3家工厂.通过现场详细调查、取样试验、1∶500地形测量、滑坡影像、视频等资料分析,对灌溉引发的罗家坡黄土滑坡的特征、滑动过程、形成机理进行了探讨.结果表明:第1次滑坡经过近2 a变形过程,整体突然失稳,高速远程滑动;第2次滑坡变形时间仅3 h,分块逐步滑动,滑动历时长而过程复杂,总体为低速远程滑动.高陡的地形和强度低、水敏感性强的土体是滑坡发生的基础,黄土台塬区长期农业灌溉是引发因素,大量水体入渗形成了20余米厚的饱和软弱基座,使抗剪强度降低,导致斜坡失稳滑动.黄土滑坡高速远程滑动的主要原因是滑坡剪出口位置高,滑动势能大,释放条件好,剪出口下部陡坡段为主要加速段;前方有开阔的滑动空间且有一定坡度、平缓的滑道;滑体底部饱和软弱黏性土在滑道上持续产生超孔隙水压力、液化等低摩阻效应,是远程滑动的润滑剂.同时,两次滑体间还存在冲击加速和能量传递作用. 相似文献
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Betekhtinite occurs in specimens of recrystallised galena from the North Lyell orebody. Its chemical composition is Cu 59.0, Pb 17.3, Fe 2.7, S 20.6, total 99.6. The thermal stability of betekhtinite is briefly discussed.
Zusammenfassung In Proben von rekristallisiertem Bleiglanz des North Lyell Erzkörpers kommt Betechtinit vor. Dessen chemische Zusammensetzung ist Cu 59.0, Pb 17.3, Fe 2.7 und S 20.6; total 99.6. Die thermische Stabilität des Betechtinites wird kurz diskutiert.相似文献
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Jacques Kornprobst 《Comptes Rendus Geoscience》2017,349(1):42-48
Boris Choubert was a strong supporter of Wegener's continental drift theory. In 1935, he published a very accurate fit of the circum-Atlantic continents, which was based on continental edges instead of coastlines; in the same paper, he interpreted the Palaeozoic belts as the result of horizontal movements of the Precambrian blocks; so, he greatly expanded the role of continental drift through time. This original and very prophetic work was almost completely ignored by his contemporaries. Thirty years later (1965), Bullard, Everett and Smith published in turn a similar but more sophisticated fit; they did not acknowledge Choubert's initial work. Bullard's fit was met with immediate and tremendous success. The present paper analyses the reasons why Boris Choubert was frustrated of his pioneering role. This lack of recognition is related to: (1) a great evolution in the geological concepts between 1935 and 1965, and (2) a poor choice of Choubert, regarding the title of his 1935 article. 相似文献