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1.
澜沧江结合带的东、西边界断裂分别为位于澜沧江西岸的吉岔断裂和位于碧罗雪山主峰的碧罗雪山断裂.澜沧江结合带由上古生界吉东龙组（P1j）、沙木组（P2sm）组成,形成于浅海陆棚-陆棚边缘盆地环境.其中,沙木组上段（P2sm2）的火山岩形成于岛弧环境.沿吉岔断裂出露的超镁铁-镁铁岩划分为2个部分：吉岔超镁铁-镁铁-斜长花岗岩具蛇绿岩特征,很可能属澜沧江洋壳的零星残片,在澜沧江洋消亡过程（早中三叠世?）中迁移定位;维登镁铁岩属阿拉斯加型,是兰坪-思茅中生代沉积盆地消亡过程（白垩纪）中沿吉岔断裂上侵的产物. 相似文献
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从鉴别陆块(地块)、结合带边界断裂入手,将滇西北大地构造划分为10个二级单元。根据地质体属性及重要断裂,在二级单元内划分出25个三级大地构造单元。结合西藏、滇西南部地区资料,归并为3个一级大地构造单元。二级大地构造单元自西向东为:独龙江弧盆系、丙中洛地块、莫得结合带、崇山地块、澜沧江火山弧、兰坪地块、云岭陆缘弧、金沙江结合带、香格里拉地块、甘孜-理塘弧盆系。分界断裂自西向东为:高黎贡山断裂、棒当断裂、福贡断裂、碧罗雪山断裂、吉岔断裂、德钦-雪龙山断裂、羊拉-东竹林断裂、金沙江断裂、香格里拉断裂、三江口断裂。该划分方案较为全面地反映了滇西北区域地质调查和科学研究的新进展,对前人划分方案进行了有依据的修改调整,二级、三级大地构造单元的划分尺度统一,厘定了各级大地构造单元的边界断裂。 相似文献
3.
云南地质(断裂)构造骨架新认识 总被引：2，自引：0，他引：2
云南最主要的骨架断裂构造是德钦-阿墨江西部大洋向东部扬子大陆及其增生带俯冲的深大断裂（F5），其西部为澜沧．西盟微板块，崇山微板块，高黎贡山微板块。从华力西运动开始至喜马拉雅运动期间，从5SW向NNE方向漂移，逐一拼贴而显今日之貌。F5深大断裂两侧，矿产形成地质环境、形成机理差异大，找矿勘查的思路和侧重点也不尽相同。卫片图上看，碧罗雪山-沦源（西）深断裂（F2）经保山市东侧往南直下，而F2断裂与南澜沧江断裂（F4）极不协调，具有前者切错后者的迹象。本文把以往认为沿澜沧江是一条完整的深大断裂划分为碧罗雪山-沧源（西）深大断裂（F2）和南澜沧江深大断裂（F4）两部分。 相似文献
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青藏高原东南部地貌边界带晚新生代构造运动 总被引：17，自引：1，他引：16
青藏高原是中国大陆最高一级地貌阶梯,其东南部地貌边界大致沿龙门山－大相岭－锦屏山－玉龙山－碧罗雪山一线分布。该文主要从青藏高原东南部地貌边界两侧的晚新生代地层记录来探讨晚新生代构造运动以及高原隆升。青藏高原东南部地貌边界带雏形出现于距今２．５Ｍａ左右,定型于１．２Ｍａ前的构造运动中,之后又在构造运动进程中不断得到加强,并最终形成今日之构造地貌格局。青藏高原从海变陆,并上升至平均海拔４５００ｍ以上, 相似文献
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大湄公河次地区有多条结合带。根据它们及相关构造单元的时空演化和配置关系，对其南北延伸和连接提出了一些新的意见：(1)印缅山脉结合带向北延与葡萄-密支那结合带汇合后，西接雅鲁藏布江结合带；(2)葡萄-密支那结合带西接雅鲁藏布江结合带，向南西被实皆右行断裂错断，其错断部分为西缅中央火山弧带北段的夏杜苏-隆东带，其南段可能潜没在古近纪沉积层之下；(3)班公湖-怒江结合带南延接潞西-抹谷结合带，再南可能潜伏在墨吉群和抹谷群推覆体之下；(4)昌宁-孟连结合带南延接清迈结合带，并在南奔一带与澜沧江结合带相交汇，原先的昌宁-孟连-清迈洋可能与西藏地区的马利-同卡裂谷盆地和双湖-冈玛错小洋盆构成一个类似现今日本海、东海海槽和南海那样呈串珠状分布的盆地带；(5)澜沧江结合带主体为一隐伏在东达山-临沧-景栋花岗岩带推覆体之下的隐伏结合带，向南接清莱—湄他一带的隐伏结合带和马来半岛的文冬-劳勿结合带，向北在西金乌兰湖一带与可可西里-金沙江结合带相交汇，可可西里澜沧江-文冬-劳勿结合带构成晚古生代冈瓦纲大陆和劳亚大陆的分界；(6)难河-程逸结合带向北延至思茅西边小黑江一带，可能终止在小黑江以北地区，向南接沙缴和贡布-何仙结合带；(7)哀牢山-斯雷博河结合带是新厘定的结合带，从哀牢山向南经南乌河带、老挝奠边府的镁铁质和超镁铁质岩线接黎府结合带和斯雷博河结合带；(8)马江结合带同哀牢山带一样，是一个早、晚古生代两个结合带相叠合的带，早古生代的结合带西接金沙江-哀牢山带，向东经红河左行断裂完全复位后可接越北的斋江结合带(华南洋俯冲形成)，与之相应的，它们北面的右江裂谷盆地可与黑河裂谷盆地(或小洋盆)和甘孜-理塘小洋盆相对应，构成一个围绕峨眉地幔柱，并受其影响而形成的晚古生代末—早中生代的盆地带。 相似文献
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对取自云南三江地区碧罗雪山与临沧岩体和西藏冈底斯岩带曲水岩体的黑云母、斜长石、钾长石与角闪石进行了^40Ar／^39Ar坪年龄测定。结果表明三个岩体的形成对代分别为420、234和43.4Ma。通过热历史与封闭温度研究表明碧罗雪山与临沧岩体在85—90Ma对经历了相同的热动力作用事件，代表了巽他次板块与欧亚板块的碰撞时间。曲水岩体在40-44Mt期间发生了快速隆起(2．6mm/a)，则标志着印度与欧亚板块的碰撞时间。 相似文献
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大湄公河次地区在地质构造上是西南三江构造带和华南加里东褶皱带的向南或南西的延伸。在理清了各构造单元的延伸趋势及其相互关系的基础上，对该区大地构造单元作了统一划分和对比。以印缅山脉结合带、澜沧江-文冬-劳勿结合带、金沙江-哀牢山-马江结合带作为主结合带，将该区划分为印澳板块、中缅马陆块、印支陆块和华南陆块4个一级单元。然后在亲冈瓦纳的中缅马陆块和亲华南型的印支陆块内再以次级结合带分别划分出4个二级构造单元：亲冈瓦纳型的西缅微陆块、腾冲-毛淡棉微陆块，保山-掸泰微陆块、临沧-景栋微陆块，亲华南型的景洪-帕府-东马来西亚微陆块、思茅-大叻微陆块、昆嵩微陆块和长山微陆块；华南陆块以越北斋江结合带为界分为扬子和华夏两微陆块。简要论述了各构造单元的基本地质特征，提出将可可西里-澜沧江-文冬-劳勿结合带作为南部冈瓦纳大陆和北部劳亚大陆的分界，指出昆嵩微陆块和长山微陆块是华夏微陆块的南西延伸，其西部的对应体可能是昌都微陆块。 相似文献
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各拉丹冬地区位于青海省唐古拉山地区北坡,变质岩研究程度较低。唐古拉山地区是揭开澜沧江结合带北延寻踪的关键性地区之一,近年笔者等在开展1∶25万赤布张错幅区域地质调查时,对该区的变质岩及围岩蚀变进行了系统调查,尤其是在测区西南部亚恰一带首次发现一套变质岩(时代问题尚存争论),但进一步丰富了唐古拉山地区变质岩内容。本文系集体力量的成果,对区内变质岩特征进行了总结,为进一步研究唐古拉山地区乃至北羌塘坳陷东南部盆地基底特征和双湖—澜沧江变质带提供了重要的基础地质资料,对高原腹地的变质岩详细研究具有启示意义。 相似文献
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羌塘盆地区域地质调查成果与进展 总被引：2，自引：2，他引：2
北部可可西里-金沙江结合带与南部班公湖-怒江结合带之间的羌塘盆地主要涉及的1：25万区域地质调查图幅有乌兰乌拉湖幅、赤布张错幅和兹格塘错幅(2000—2002年)，取得的主要进展如下。 相似文献
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Guboglo M. N. 《GeoJournal》1980,4(1):53-58
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen. 相似文献
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Jiayu Rong Michael Melchin S. Henry Williams Tatyana N. Koren Jacques Verniers 《《幕》》2008,31(3):315-318
The Global Stratotype Section and Point （GSSP） for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy （SSS） proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy （ICS）. The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob＇s Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs. 相似文献
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Deviation of the major axis of the inertia ellipsoid of the Moon from the direction toward the Earth
B. P. Kondratyev 《Astronomy Reports》2017,61(8):709-714
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″. 相似文献
14.
东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。 相似文献
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Important tendencies in development of the world mineral-resources sector at the beginning of the 21st century were an increase in production and consumption of mineral materials differentiated by types of metals and nonmetallic mineral raw materials, by countries and regions, as well as the concentration of the production of mineral raw materials in a small number of countries, and a reduction in industrial reserves of minerals in the world economy, even at the current stage of their extraction. These tendencies should be taken into account in working out a strategy for development of the Russian mineral raw-material base. 相似文献
18.
Fouad N. Ibrahim Dr. 《GeoJournal》1988,17(1):133-141
Taking the example of W Sudan, an analysis of the climatic incidents leading to the two recent famine disasters is made. On this natural background, the human side is investigated. Focus is directed towards the fragile economic structure of the famine-prone population groups. An early-warning system for famine in the Sahelian Zone is proposed taking grain production and storage, livestock development and the relationship between the prices of livestock and grain as major indicators. 相似文献
19.
郯庐断裂南段研究进展与断裂性质讨论 总被引：13，自引：3，他引：13
据1：5万区域地质调查和专题研究资料，就郯庐断裂带是否南延与消失的原因，其与大别—苏鲁造山带交截形成的假位错效应，以及与中新生代沉积盆地形成演化的关系等作了新的阐述。在此基础上，讨论了郯庐断裂带是否为巨大的左行平移断层或转换断层。认为郯庐断裂带可能是在“古郯庐带”的基础上于早侏罗世重新活动、白垩纪强烈活动的地堑型枢纽断裂带。 相似文献
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The Importance of the Precipitation and the Susceptibility of the Slopes for the Triggering of Landslides Along the Roads 总被引：3，自引：1，他引：2
Clemente Irigaray Francisco Lamas Rachid El Hamdouni Tomás Fernández José Chacón 《Natural Hazards》2000,21(1):65-81
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning. 相似文献