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内蒙古四子王旗地区地球化学特征表明:二叠系大石寨组二、三、四段富集金、银、锰、铜等成矿元素,哲斯组富集金、钨等成矿元素,成矿元素具有强分异性.西力庙向斜、艾力登查干德背斜为主要控矿构造,区内岩浆热液活动,提供了丰富矿源.研究区共圈出综合异常18处,对综合异常进行分类,其中甲类异常2处,乙1类异常4处,乙2类异常5处,乙3类异常4处,丙类异常3处.依据区域成矿地质背景、区域地球化学特征、研究区地球化学异常特征及异常查证成果,划分了四个成矿远景区. 相似文献
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黑龙江塔源地区金银铜成矿系统研究 总被引：6，自引：0，他引：6
以黑龙江塔河地区的地质，地球物理，地球化学等多源地质信息为基础，对该区的地质背景，矿区地质，成矿要素等进行了综合分析，建立了该区的金，银，铜矿产的成矿系统模型。模型指出，大陆边缘活动带，古元古宙基底，以北东向为主导的断裂构造系统，以及火山岩－侵入岩是区内金，银，铜矿成矿系统形成的有利大地构造环境和成矿地质背景。在地球物理上有利的成矿地质背景表现为复杂磁场区和重力相对高场区。Au,Ag,As,Sb,Cu,Bi组合异常成矿系统的地球化学异常标志。 相似文献
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区域成矿地球化学理论以成矿物质为主体,以成矿地质条件为背景,主要研究大型超大型矿床在成壳、成岩、成矿与成晕过程中的地球化学规律。区域成矿地球化学理论体系是基于成矿地质过程与成矿级次建立的研究框架,包括成矿地球化学块体理论、成矿地球化学异常系列理论、成矿地球化学次级分带理论和成矿地球化学原生分带理论,主要研究成矿省(域)、成矿区带、成矿亚带和矿床等各级次成矿地球化学问题。在区域成矿地球化学理论指导下,结合我国长期形成的区域、普查与详查化探工作程序特点,建立与之相适应的区域矿产资源地球化学评价体系和区域地球化学勘查方法技术体系,系统研究不同层级的成矿与找矿地球化学问题。各体系之间既密切相关地联系在一起,又具有独立的研究内涵与范畴。本文结合西南三江北段成矿带沱沱河区域化探异常集群的重大发现,主要讨论区域成矿地球化学理论体系及相关的评价体系与方法体系问题。 相似文献
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应用地球化学基础理论和多元计分析方法研究东石门斑岩型铜矿床地球化学特征,初步总结了矿致导致异常特征,建立了该矿床的轴向元素分带序列,提出了该矿床的成矿地球化学指标及其深部的成矿预测。 相似文献
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本文以牟平－乳山地区浅成热液金矿床为研究对象，从成矿的地质、地球化学基础资料分析入手，建立金矿找矿的地质和地球化学特征标志，根据各地质特征标志对金矿贡献的大小将各标志数量化；对地球化学数据进行了特征提取。通过金矿各因素相互之间的关系，将地质、地球化学因素有机地结合起来，建立了统一的数学评价模式，从而能够综合评价浅成熟液金矿的地球化学异常。 相似文献
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通过分析桐木铜多金属成矿亚带地质-地球物理特征可知,研究区磁场特征较为简单,为平稳的弱磁场区,放射性场则呈现出明显的平行条带状特征,与断裂及地层走向相同。对重点异常开展了地物化综合研究,并以此为基础建立了该成矿亚带地质-地球物理-地球化学找矿标志,区内HF35等重点放射性局部异常具较大寻找铜多金属矿的潜力。成矿亚带受构造和围岩双重控制作用明显,但主要受桐木区域性大断裂控制,大断裂及次级构造所形成的构造破碎带对成矿最为有利。 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
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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
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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
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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