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祁连山二叠纪植物群的特征

甘肃地质 1987年 37-60页

作者：王德旭贺勃张淑玲甘肃省地质矿产局地质科学研究所

1927—1935年中瑞考察团成员柏克塞尔(Bexell)报导了南山剖面,该剖面第6层——植物层C所含化石经赫纳(Halle)鉴定有:Phyllotheca deliquescens,Calli-pteris sp.(***),Iniopteris sibirica,Brongniartites salicifo-lius,Zamiopteris glo ssopteroides,Rhipidopsis lobata,Noegge thiopsis sp.等10个安加拉植物群分子,引起了中外地质学家的重视和极大的兴趣。Halle的一篇关于南山的新发现,即安加拉植物群盖覆于华夏植物群的论文,是在1935年Heerlen所举

关键词：二叠纪地层祁连山区植物化石层华夏植物群大黄沟组安加拉植物群植物

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祁连山二叠纪植物群的特征

甘肃地质 1986年第2期 37-60页

作者：王德旭贺勃张淑玲甘肃省地质矿产局地质科学研究所

1927—1935年中瑞考察团成员柏克塞尔(Bexell)报导了南山剖面,该剖面第6层——植物层C所含化石经赫纳(Halle)鉴定有:Phyllotheca deliquescens,Callipterissp.(***),Iniopteris sibirica,Brongniartites salicifolius,Zamiopteris glo s... 详细信息

关键词：二叠纪石炭纪地层祁连山区植物化石层华夏植物群安加拉植物群大黄沟组植物

Have a correct understanding of the attribute of geologic environmentgive full play to the role of geoscience in environmental protection

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Journal of Environmental Sciences 1995年第4期7卷 491-501页

作者： Ha Chengyou(institute of Environmental geology, Ministry of geology and mineral resources, Beijing 100081 , China)

Ｈａｖｅａｃｏｒｒｅｃｔｕｎｄｅｒｓｔａｎｄｉｎｇｏｆｔｈｅａｔｔｒｉｂｕｔｅｏｆｇｅｏｌｏｇｉｃｅｎｖｉｒｏｎｍｅｎｔｇｉｖｅｆｕｌｌｐｌａｙｔｏｔｈｅｒｏｌｅｏｆｇｅｏｓｃｉｅｎｃｅｉｎｅｎｖｉｒｏｎｍｅｎｔａｌ... 详细信息

ＨａｖｅａｃｏｒｒｅｃｔｕｎｄｅｒｓｔａｎｄｉｎｇｏｆｔｈｅａｔｔｒｉｂｕｔｅｏｆｇｅｏｌｏｇｉｃｅｎｖｉｒｏｎｍｅｎｔｇｉｖｅｆｕｌｌｐｌａｙｔｏｔｈｅｒｏｌｅｏｆｇｅｏｓｃｉｅｎｃｅｉｎｅｎｖｉｒｏｎｍｅｎｔａｌｐｒｏｔｅｃｔｉｏｎＨａＣｈｅｎｇ...

关键词： geologic environment attribute geologic resources geologic capacity geologic disaster.

Types and Metallogenic Models of Nickel Sulfide Deposits of China

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Acta Geologica Sinica(English Edition) 1988年第2期1卷 193-206页

作者： Tang Zhongli Ren Duanjin bureau of geology and mineral resources of gansu Province, Lanzhou, gansu bureau of geology and mineral resources of gansu Province Lanzhou Gansu

Most of the sulfide nickel deposits in China occur on the margins of platforms and their outer mobilebelts. The ore-bearing basic-ultrabasic rock bodies were formed in the Proterozoic and Variscan. The types ofmetallogenic rock bodies include ultrahasic-basic complexes related to volcanism in eugeosynclines andultrabasic rock bodies, ultrabasic-basic complexes and basic rock bodies related to deep fractures. On the basisof ore-forming processes and modes, nickel sulfide deposits of China may be divided into two major types:in-situ magmatic liquid unmixing deposits and deep-seated magmatic liquid unmixing injection deposits. Thelatter may by subdivided into four types: single injection deposits, multiple injection deposits, and pulsatory in-jection depositis, and late injection deposits which may inject into either comagmatic rocks or other kinds ofcountry rocks. Two metallogenic models for nickel sulfide deposits are proposed in this paper.

关键词： Types and Metallogenic Models of Nickel Sulfide Deposits of China

Geochemical Conditions of Metallization of the Lijiagou Pb-Zn Deposit, gansu Province

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 89-99页

作者： Lin Bing Zhejang institute of geology and mineral resources, Hangzhou Sun Sheping Zhe jiang institute of geology and mineral resources Hangzhou

The Lijiagou Pb-Zn deposit in gansu Province is a syngenetic hydrothermal-depositonal and meta-morphosed hydrothermal weakly-reworked stratabound ore deposit. The metallogenic physicochemical condi-tions of the deposit are thoroughly dealt with in this paper according to its different mineralization *** on the systematic study of metallogenic material sources, it is considered that the ore-forming metals, oresulphur and water of mineralizing fluids are mainly derived from the basement, reduction sulphur of marinesulfate and infiltrating heated meteoric water and partially recharged sea water, respectively. Finally, themetallogenic model of this deposit is established.

关键词： Geochemical Conditions of Metallization of the Lijiagou Pb-Zn Deposit Zn Pb

Discovery of Fossil Charophytes from the Late Triassic Xujiahe Formation and Early Jurassic Lower Yimen Formation, Sichuan Province, and Its Significance

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 301-309,327页

作者： Liu Junying Chen Zhongliang institute of geology, Chinese Academy of Geological Sciences, Beijing Panxi Geological Party, Sichuan bureau of geology and mineral resources, Xichang Liu Linqun institute of geology Chinese Academy of Geological Sciences Beijing China

This paper describes the fossil charophytes collected from the Late Triassic Xujiahe Formation in Dazuand Early Jurassic Lower Yimen Formation in Xichang, Sichuan Province, and their significance. Up to now,papers dealing with fossil charophytes of the Late Triassic, especially of the Early Jurassic, have been rarelypublished. The description of the two new species of Porochara, P. dazuensis and P. xichangensis, and theirfossil assemblage not only provides an important basis for classification and correlation of red beds insouthwestern China but reveals for the first time the features of the charophyte flora of the Late Triassic-EarlyJurassic in the area, thus offering valuable data for the establishment of Triassic and Jurassic charophyte fossilzones in China.

关键词： Sichuan Late Triassic Early Jurassic charophyte fossil

Magmatic Sulfide Ni-Cu Deposits in China

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Journal of Earth Science 1999年第1期18卷 12-16页

作者： Tang Zhongli gansu bureau of geology and mineral resources, Lanzhou 730000

Deep seated magmatic liquation injection deposits form a major type of magmatic sulfide deposit in China. The reserves of nickel and copper in this type of deposit may attain several hundred thousand tons (*** 7 and Karatunggu) to nearly ten million tons (***). Those deposits can be classified as large or superlarge deposits. The ore grade is relatively high, commonly with w (Ni)>1 %. The mineralized intrusions are small in size, generally only 0.0 n km 2 to 0. n km 2, with the largest one not exceeding a few km 2. Before intruding, the primary magmas have undergone liquation and partial crystallization at depth; as a result, the magmas have partitioned into barren magma, ore bearing magma, ore rich magma and ore magma, which then ascended and injected into the present locations once or multiple times, to form ore deposits. The above mentioned mineralizing process is known as deep seated magmatic liquation injection mineralization. The volume of the barren magma is generally much larger than those of the ore bearing magma, ore rich magma and ore magma. In the ascending process, most of the barren magma intruded into different locations or outpoured onto the ground surface, forming intrusions or lava flows. The rest barren magma, ore bearing magma, ore rich magma and ore magma may either multiple times inject into the same place in which rocks and ores are formed or separately inject into different spaces to form rocks and ores. Such deep seated magmatic liquation injection deposits have a much smaller volume, greater ore potential and higher ore grade than those of in situ magmatic liquation deposits. Consequently, this mineralizing process leads to the formation of large deposits in small intrusions.

关键词： deep seated liquation injection spatio temporal distribution magmatic sulfide deposit.

Analytical Model for the Palaeoenvironmental Evolution of the Nihewan Beds

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 77-86页

作者： Yue Jun Wen Qizhong Tianjin institute of geology and mineral resources institute of Geochemistry, Academia Sinica Tianjin institute of geology and mineral resources China

In this paper, the evolutional characteristics of palaeoclimate and oxidation-reduction conditions as well asacidity-alkalinity environment are discussed by means of the step-regression, cluster, optimal partitioning andcorrelation analyses of CaCO_3, C / P_2O_5, Fe^(2+) / Fe^(3+), pH and Eh values, taking the Xiaodukou section in theNihewan basin as an example. The CaCO_3, C / P_2O_5 and pH were calculated respectively using the optimalpartitioning method. Thus five cold zones and six warm zones as well as five reduction and six oxidation zoneswere distinguished. Then the inductive method was used to produce four numerical groups: 8.10, 8.3-8.4,8.6-8.7 and 8.9-8,97. The above-mentioned results are respectively based on CaCO_3 content, C/P_2O_5 andpH values. From Fig. 3, Tables 1 and 2 it can be seen that the Nihewan Beds were formed mainly under a re-duction and slightly alkaline environment of cold climate, with pH values of 8.3-8.4. Fig. 3 shows that bed 35is approximately near the boundary between the Brunhes and Matuyama polarity epochs, 0.73 Ma in age; bed26 is roughly near the Jaramillo event (base), 0.97 Ma in age; bed 18 coincides roughly with themagnetostratigraphic boundary of 2.00 Ma (?). Bed 13 may be the Pleistocene-Pliocene boundary, 2.48 Ma inage. Thus geochemical zones Ⅰ, Ⅱ, Ⅲ and Ⅳ include respectively cold zones 1; 2 and 3; 4; and 5.

关键词： Analytical Model for the Palaeoenvironmental Evolution of the Nihewan Beds

Minerogenetic Model for Two Types of Fluorite Deposits in Southeastern China

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 75-88页

作者： Li Changjiang Jiang Xuliang Zhejiang institute of geology and mineral resources, Hangzhou Liu Linqun Zhejiang institute of geology and mineral resources Hangzhou

On the basis of the studies of field geology, strontium, hydrogen and oxygen isotopes and REEgeochemistry, coupled with the dating of mineralization, the authors suggest a minerogenetic model of circula-tion and drawing of Late Cretaceous geothermal waters for the fluorite deposits in southeastern China. Thismodel includes two types of mechanism: 1) the leaching-out and drawing through deep circulation of thegeothermal water, and 2) the leaching-out and drawing through shallow circulation of the water. The fluoritemineralization of Mesozoic volcanic rock terrain is related mainly to the former mechanism, with the mineraliz-ing material coming chiefly from the Precambrian metamorphic rocks of the basement underlying the hostrocks; while that of Yanshanian granite terrain is associated with the latter mechanism, with the mineralizingmaterial derived primarily from the host granites and sedimentary rocks.

关键词： Minerogenetic Model for Two Types of Fluorite Deposits in Southeastern China