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地球科学在最近几年的发展过程中,显示出了许多新的变化和新的趋势。理会这些情况,对我们工作的前进,显然很有必要。现仅就所想到的几点提出来与大家讨论。一、地球科学研究工作的“指导思想”和生产关系”在发生着变化 (一)近几年来地球科学研究及其所取得的大量事实表明:地球在漫长地史过程中,并不仅仅是均变,也有“灾变”。地质作用的进行,并不仅仅是“连续的”,而更多的是“不连续的”。即是说,地球在其地史变化历程中,既有“演化”,也有“变革”;既有“量 相似文献
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本文系叶莲俊先生所著“中国磷块岩矿床的若干特点与成矿远景”一交中的一部分(第四章),而这篇文章将编入苏联专家布申斯基与叶连俊合著的“中国磷块岩的形成特点、矿石类型及远景评价”一书,该书即将由科学出版社出版。该书总结了我国几年来磷矿工作的成果,在理论上实践上都有巨大的意义。现在我们从这本书中选出论述中国磷块器的形成条件的这一章,刊登于此,以供参考。 相似文献
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刘鸿允教授是国内著名的地层学家和古地理学家。《中国震旦系》是他最近的新著,是他近卅余年来辛勤耕耘的结晶。这本专著的问世,展示了中国震旦纪地层学研究进入到了一个新的阶段。书中陈述了他的许多有影响的新见卓识,标志着他在新时代地层学方面的追索与造诣。在专著中他不仅探讨了生物地层 相似文献
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近年来地质工作者对若干重要沉积矿床进行了不少的调查研究,认识到中国沉积矿床的若干成矿特点。因此对这些成矿特点作进一步的研究是有意义的。现在就这一方面提出以下几点意见供大家参考。 相似文献
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Sedimentary mineral deposits cannot be formed by any kind of simple chemical reactions,but are products of a complex multi-episodic process depending on multiple factors,The whole process is governed by a combination of sedimentary,geochemical,biogeochemical,organic geochemical,paleoclimatical,mechanical agents as well as by the properties of relevant earth crust segment and its structural making up and tectonic mobility A Sedimentary ore deposit is nothing but a special kind of sedimentary facies,characterized by definite sedimentary assemblages,Different genetic types of ore deposit and different ore associations characterize different sedimentary assemblages in different ore-forming belts.Crustal movement,including orogenic,epeirogenic and,oparticularly eustatic events,controls the formation and distribution of all kinds of sedimentary mineral deposits,most of which occur within the transgression front in the lower part of marine transpressive series.Mineral deposits of economic importance cannot be precipitated directly from sea water,but are products of terrestrial imbibition,biological enrichment and pore water concentration instead,Deposits formed above the wave base in the inner continental shelf under strong dynamic condition of sea water are often large and predominantly clastic in texture with commercial grade.Below the wave base in the outer continental shelf environment,where it is more or less dynamically stagnant and oxygen-deficient,the resulted in dustrial ore deposits are mostly of diagenetic or strata-bound type,formed through deep-burying diagenesis.The theory of multi-factor and multi-episodic metallogenesis includes three major aspects:the ore-forming process,the sedimentary environment and the geological background.The study of the forma tion process itself and the sources of ore-forming elements would provide useful clues to further prospectiong Whereas,invstigations of the sedimentary environments should shed light on the spacial distribution of deposits and the analysis of geological background would contribute a lot to our knowledge of the temporal evolution of sedimentary metallogenesis. 相似文献
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一、引言在锰矿的探索工作中,有两个实际的基本问题必需寻求解决,那就是; 1.我们应该用什么样的根据去判断某一地点有无某一种矿产的可能性,以及某一矿床可能隶属的工业类型; 相似文献