共查询到20条相似文献，搜索用时 78 毫秒
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为推动中国地质学会地学科普研学工作的开展,根据 《中国地质学会精品地学研学路线、课程评选办法(试行)》, 学会组织开展了第二批精品地学研学路线、第一批精品地学 研学课程的申报、推荐和评审工作。 相似文献
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正为了进一步加强地质学科学普及,鼓励会员参与地质科普,中国地质学会设立了科普奖。中国地质学会第一届科普奖近日揭晓,5位科学家获人物奖,5组作品获产品奖。该获奖名单是由各省级地质学会和中国地质学会各专业委员会推荐,经专家评选后确定,并于2020年4月21日～26日在中国地质学会网站公示。 相似文献
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Mathematical Geosciences - 相似文献
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The Geology of the Great 'Dyke', Zimbabwe: The Ultramafic Rocks 总被引：7，自引：3，他引：7
Textural and mineral chemistry data for the ultramafic sequenceof the Hartley Complex are presented with the object of evaluatingemplacement mechanisms, crystallization history and sub-solidusre-equilibration processes for the Great ‘Dyke’.Mineral chemistry indicates in situ crystallizaration for theultramafic sequence, whereas textural evidence suggests thatlimited crystal settling of chromite took place. It is concludedthat crystallization of cumulus phases occurred at or near thefloor of the magma chamber. The mineral chemistry indicates that the volume of magma fromwhich each unit crystallized was significantly smaller thanthat represented by the stratigraphic succession of the HartleyComplex. The magma chamber may effectively have been part ofan open system during the crystallization of the ultramaficsequence. The results are consistent with the concept of a stratifiedmagma chamber and the process of double-diffusion convection. Modelling of the liquid line of descent and crystallizationsequences indicate that none of the previously proposed initialliquid compositions are likely to have constituted the parentalmagma of the Great ‘Dyke’. Rather than komatüticor exceptionally high magnesium liquids, as previously suggested,a parental magma with about 15 per cent MgO, similar to thecomposition of the chill phase of a dyke parallel to and inclose proximity to the East Dyke is in closest agreement withthe observed and modelled results. Chromite compositions are strongly related to textural and mineralogicalenvironments. Seam chromitites are higher in Cr, Mg and Fe3+than chromites enclosed in silicates. Chromite enclosed in cumulusolivine is higher in Fe2+ than that in coexisting pyroxenesbut there is little difference in the proportions of the trivalentcaptions. Seam chromitites are considered to have precipitatedin response to increases in foi associated with periodic influxesof magma into the magma chamber. The higher ferric iron contentof the seam chromitites compared with the chromite enclosedin the silicates is consistent with such a mechanism. Compositional zoning in olivine and pyroxene adjacent to enclosedchromite grains is interpreted as reflecting subsolidus re-equilibrationwith cooling. Zoning profiles exhibit strong crystallographiccontrol. Computer modelling using finite difference approximationshas allowed controlling factors to be assessed by optimizationof the modelled parameters to give closest agreement to themeasured results. Interdiffusion coefficients and distributioncoefficients for Fe2+ and Mg for olivine and pyroxene with chromiteare modelled and compared with published data. Indicated blockingtemperatures for olivine are of the order of 600 °C to 700°C and 750 °C to 850 °C for orthopyroxene. Thuschromites enclosed in orthopyroxene are more Mg-rich than thoseenclosed in olivine. Coarse-grained seam chromitites have beenlittle modified subsequent to crystallization but the compositionsof the associated silicates have been influenced by the modalabundance of the chromite. Geothermometers based on chromite-silicate equilibria are probablynot applicable to layered intrusions, but information on thermalhistories may be provided by evaluation of the diffusion profiles. 相似文献
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充分发挥专业课程的多维度育人功能是打通基础学科高层次人才培养的关键一环。作为地质学及其相关专业的第一门专业入门课程,《普通地质学》课程主要教授学生地球科学的基本知识、基本技能和基本地质思维等专业知识,同时培养学生的专业兴趣。面对新时代高层次地学人才培养的要求,需要深入挖掘该课程的思政元素,实现教学理念从单纯的传授基础知识、激发专业兴趣到科学素养和人文素养拓展,开启《普通地质学》课程服务地学高层次人才培养的大门。充分利用“将今论古”思想和动力地质作用这两个课程核心内容,培养学生的开拓创新精神和跨学科能力,提升学生的科学素养。同时,依托地质过程的复杂性和庞大的地质时空观等课程核心内容,培养学生的工匠精神、大格局观和发展观,提升人文素养。 相似文献
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G.O. Jenkins C. Foster P.M. Hopson 《Proceedings of the Geologists' Association. Geologists' Association》2011,122(5):906-922
The Cretaceous and Palaeogene sedimentary rocks that crop out on the Isle of Wight are highly prone to landsliding and the island offers an important field laboratory wherein to investigate a number of the different types of failure. Many of these landslides represent a significant engineering hazard, with several urban areas requiring remedial work and planning constraints (e.g. The Undercliff and Seagrove Bay) to aid development. Previous studies have thoroughly investigated the major landslides in the Undercliff area around Ventnor and presented a mechanism for that massive failure. This overview of the landslides throughout the Isle of Wight by the British Geological Survey was completed as part of the multidisciplinary survey of the surface geology, structure, geophysical response and offshore interpretations of the island between 2007 and 2010. The survey has collected new observational data on the extensive coastal landslides, as well as the distribution, nature and mechanism of failure of the lesser-studied inland examples. 相似文献
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J.L. Whitford-Stark 《Earth》1982,18(2):109-168
The products of volcanism on the Earth and Moon differ widely in terms of morphology, distribution, composition, and age. These differences result partly from the different thermal histories of the two bodies and partly through the different controls on volcanic eruption conditions. The controls of volcanism are here separated into three groups: (1) controls which remain constant on any one body but which differ from planet to planet: (2) parameters that are controlled by the rheology of the magma: and (3) controls which are intrinsic properties of individual eruptions and are themselves dependent upon the planetary and rheological variables. In terms of planetary variables it can be predicted that lunar volcanic morphologies are influenced by greater tephra range, hemispherical eruption clouds, lesser lithostatic pressures at corresponding depths, slower cooling, slower erosion, lesser horizontal stress differences, and no features typical of hydrosphere-magma interaction. In terms of rheology, the lunar eruptions had different rock and gas compositions, low yield strengths and viscosities, and high densities. Many lunar basalts appear to have been produced at high eruption rates, to have been derived from monogenetic volcanoes, and to have flowed in a turbulent manner.The weight of available data points to the vast majority of lunar craters being of impact origin though some dark halo craters, sinuous rille source craters, rimless pits, and craters atop domes and cones are undoubtedly of volcanic origin. Other impact craters appear to have been modified by volcanic events. Included within this latter group are the floor-fractured craters and the mare basins.Studies of volcanic morphologies on bodies other than the Earth may help isolate the effectiveness of those controls of volcanism which remain constant on any one body. Although volcanology has advanced substantially within the last few decades, much more detailed integrated scientific research is required before we are able to predict confidently the environmental hazards that result from volcanism and to understand the role of volcanism in planetary evolution. 相似文献
