用户名: 密码: 验证码:
西藏甲玛铜多金属矿伴生元素金的赋存状态研究
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
西藏墨竹工卡县甲玛铜多金属矿床位于青藏高原冈底斯成矿带中南部,是目前西藏最具有经济价值的超大型铜多金属矿床之一。该矿床不仅规模巨大,而且除主元素铜、钼达到超大型外,其他有用组分金、银、铅锌均达到大型规模。本文通过对金的赋存状态进行研究,将有助于资源的合理利用,提高矿床的经济价值,也将有助于我们了解为什么甲玛铜多金属矿有别于冈底斯成矿带其它中新世斑岩铜矿,富含金等成矿元素。
     在冈底斯成矿带,像甲玛这样矿体规模巨大、矿石类型复杂、成矿元素丰富、富矿体厚度大的斑岩-矽卡岩型矿床实属罕见。而且,在主矿体的边部已发现石英闪长玢岩型的独立金矿体,因此,研究矿石中金的赋存状态意义重大。
     论文在广泛收集资料、野外地质调查和钻孔编录的基础上,通过对岩矿石样品的采集、基本化学样品的分析数据的处理、镜下光薄片鉴定、电子探针测试(黄铁矿、黄铜矿、斑铜矿、自然金为主)和电镜扫描等方面的研究,初步掌握了甲玛含金矽卡岩型矿石的地质特征、金的分布规律、金的运移沉淀和赋存状态并取得了如下认识:
     通过野外调查、剖面测制、平硐编录、岩矿鉴定、分析测试等工作,确定甲玛矿床属于斑岩型-矽卡岩型铜多金属矿,矿石中金的含量较高,平均品位约0.33g/t,最高可达98.7g/t,伴生金一般富集于矽卡岩中的含铜矿石。而在角岩型矿体、斑岩型矿体中含量则很低,总体达不到伴生有用组分的含量。主要富金矿石位于矿区的东北部ZK025附近,垂向分布于海拔4280~4550m之间的矽卡岩铜钼矿体中。通过组合分析发现,矿床中金与铜存在明显的正相关关系,其次是银,而金与其它元素间的相关性较差。
     矿体中的金的赋存状态主要有以下几种方式:一、以自然金的方式产于斑铜矿的裂隙中,部分产于石英裂隙中;二、以自然金和银金矿的方式产于闪锌矿和斑铜矿的矿物颗粒之间;三、以自然金和银金矿的形式产于斑铜矿和黄铜矿的边缘,形成连生金结构;四、以自然金和银金矿的形式包裹于多金属硫化物中,其中黄铜矿和斑铜矿是包裹金的主要载体。此外,在矿区的脉石矿物中还发现有自形粒度的铜金矿和含金自然银。
     金的粒度较小,属于显微金,大部分金在0.06~0.0002 mm之间,在选冶过程中需要将矿石磨至0.06mm以下,有利于金的充分回收。由于独立金矿体的金主要赋存于黄铁矿和毒砂中,因此在选冶过程中应区别处理。
Jiama copper-polymetallic deposit in Mozhugongka county of Tibet is located in the south-central Gangdise ore belt of Tibetan Plateau.And it is one of the most economic value of ultra-large type copper-polymetallic deposits. The deposit is not only huge in the scale, but also many main elements like copper and molybdenum reach the ultra-large type and except these two elements, other useful components such as gold, silver, lead and zinc all achieve a large scale. Based on the studying of gold’occurrence state, it will contribute to make good use of resources and improve the economic value of deposits, and it will also help us understand why Jiama copper polymetallic is different from other Gangdese Miocene porphyry copper deposits, riched in gold and other ore-forming elements.
     In the Gangdese metallogenic belt, it is very rare to see such huge orebody like Jiama deposite. It is huge, of complexe ore types and of rich ore-forming elements, and it belongs to porphyry– skarn deposite of high-grade ore body thickness. Moreover, at the margin of the main ore body, we have found independent gold of quartz diorite porphyry type, and therefore the study of the occurrence of gold in ore is of great significance.
     The discourse is on the basis of wide collecting predecessor's information, geological survey and drill core logging. And brings to success by ore samples collection, processing of the basic chemical analysis data of ore samples, identification of the polished thin section under the microscopy, electron probe microanalyser (pyrite, Copper, bornite, native gold-based) and scanning electron microscopy. Through those methods above, we have a preliminary grasp of the Jiama auriferous skarn-type ore geological features, the distribution and the precipitation process of gold’s occurrences and migration. Finally, we achieved the following understanding:
     Through field investigation, profile measurement system, adit logging, rock and mineral identification, analysis and testing, it is ascertained to figure out that Jiama deposit is a porphyry - skarn copper-polymetallic ore. It has a high content of gold in ore, with an average grade of about 0.33g / t, the highest being 98.7g / t, and associated gold generally enriches in the copper-bearing ore of skarn. However, associated gold is in the condition of low content in hornstone orebody and porphyry orebody, which in general doesn’t reach of the content of useful components associated. The gold rich ore is mainly located near the northeast ZK025 of the mining area, and vertically distributes in skarn copper-molybdenum ore body at an altitude of between 4280 ~ 4550 meters. Through a combination of analysis, gold and copper of the deposits is in the obvious positive correlation, and so is gold and sliver. While the correlation of gold and other elements is poor.
     The occurrence state of gold in orebody mainly has the following ways: firstly, Au appears in fracture of bornite in the form of native gold or it is partly wrapped in cracks of quartz; Secondly, Au presents among mineral particles of sphalerite and bornite in the way of native gold and electrum; Thirdly, Au produces at the edge of bornite and chalcopyrite in the way of native gold and electrum, forming structure of attachement gold ; Fourthly, Au is wrapped in polymetallic sulfide in the form of native gold and electrum, and chalcopyrite and bornite are the main carriers of inclusion gold. In addition, in the gangue minerals of the mining area, it is also found that there are copper gold and gold-bearing native silver which respectively form grain size of their own.
     The particle size of gold is relatively small, which belongs to microscopic gold.The size of most gold is among 0.06 ~ 0.0002 mm. In the process of beneficiation and metallurgy, the size of minerals needs grinding to 0.06mm below, which is good for the full recovery of gold. As the independent gold ore bodies mainly occur in pyrite and arsenopyrite, they should be dealt with differently in the process of beneficiation and metallurgy.
引文
Batchelder J N. Light stable isotope and fluid inclusion study of the porphyry copper deposit at Copper Canyon, Vevada [J]. 1977, Econ Geol, 1977, 72 (1): 60~70.
    Bowman J N., O’Neil J R, Essene J. Contact skarn formation at Elkhorn ,MontanaⅡ:origin and Evolution of C-O-H skarn fluid [J]. Econ Geol,1985,285 (7): 621~660.
    Bowman J R.Stable isotope systematics of skarns [A]. In: Lentz D R, ed. Mineralized intrusion-related skarn systems[C]. Quebec.Short Course Series 26,1998,99~147.
    Clement Gariepy, Claude J.Allegre and Rong Hua Xu.1985.The Pb-isotope geochemistry of granitoids from the Himalaya-Tibet collision zone: implications for crustral evolution[J].Earth and Planetary Science Letters ,74:220~234.
    Cannon R S, Pierce A P, Antweiler J C et al.,1961The data of lead isotope geology related to problems of ore genesis [J].Economic Geology,56(1):1~38.
    Doe B R, Stacey J S. The application of lead isotopes to the problems of ore Genesis and ore prospect evaluation: a review [J] Econ Geol, 1974, 69 (6): 757-776.
    Faure G and Mensing T M. 2005. Isotopes: Principles and Applications (Third Edition) [M]. NewYork: John Wiley& Sons. 256~283.
    Hoefs J. 1997. Stable Isotope Geochemistry (Forth Edition) [M]. Berlin: Springer-Verlag. 119~120.
    Ohmoto H. Stable isotope geochemistry of ore deposits [J]. Rev. Mineral, 1986, l6 (1): 491一559.
    Ohmoto H and Rye R O. 1979. Isotopes of sulfur and carbon [C]. In Barnes H L (ed), Geochemistry of hydrothermal ore deposits [A]. New York: John Wiley&Sons. 509~567.
    Pinckney,O.M.te al.,1972.Fractionation of sulfur isotopes during ore-deposition in the upper Mississippi Valley pb-zn district:Econmic Geology,67(3):315~328.
    Staecy J S and Kramers J D. 1975. Approximation of terrestrial lead isotope evolution by a two stage model [J]. Earth and plant Sci Letters, 26 (2): 207~221 ( in Chinese with English abstract).
    Zartman R E and Doe B R. 1981. Plumbtectonics-The model [J].Tectonophysics, 75 (1-2): 135~162.
    Boyle R W. 1984,金与金矿床地球化学[M].马万钧等译.北京:地质出版社, 1984: 26~35.
    程顺波,庞迎春,曹亮.2008.西藏蒙亚啊矽卡岩铅锌矿床的成因探讨[J].华南地质与矿产,10(1):50~56.
    地质部宜昌地质矿产研究所同位素地质研究室,1979.铅同位素地质研究的基本问题[M].北京:地质出版社.35~137.
    杜光树,姚鹏,潘凤雏等.1998.喷流成因夕卡岩与成矿-以西藏甲马铜多金属矿床为例[J].成都:四川科学技术出版社
    冯孝良,管仕平,牟传龙等.2001.西藏甲马铜多金属矿床的岩浆热液交代成因:地质与地球化学证据[J].地质地球化学,29(4):40~48
    胡涛,陈容美,张振儒.1992.伴生金的赋存状态研究的意义及方法[J].黄金,13 (1):1~17
    侯增谦,曲晓明,王淑贤等.2003.西藏高原冈底斯斑岩铜矿带辉钼矿Re-Os年龄:成矿作用时限与动力学背景[J].中国科学(D辑),33 (7):609~618
    侯增谦,曲晓明,杨竹森等.2010.青藏高原碰撞造山带:ó.后碰撞伸展成矿作用X[J].矿床地质,Vol.25,No.6
    金章东,李福春.1998.斑岩型铜矿床成矿过程中铜的迁移与沉淀机制研究新进展[J].矿产与地质,V01.12,No.2
    李光明,芮宗瑶,王高明等,2005.西藏冈底斯成矿带甲马和知不拉铜多金属矿床的Re-Os同位素年龄及其意义[J],矿床地质. 24 (5) :481~489.
    李光明,王高明,高大发,黄志英,姚鹏.2002.西藏冈底斯南缘构造格架与成矿系统[J].沉积与特提斯地质,22(2):l~7
    李金高,王全海,郑明华等.2001.西藏sedex型矿床赋矿性质对成矿元素的制约作用[J].沉积与特提斯地质,21(4):ll~20
    李胜荣,袁万明,屈文俊等.2008.西藏墨竹工卡县甲马多金属矿床几组年龄数据的比较与成因研究[J].岩石学报,24(2):511~518
    刘家军,何明勤,李志明等.2004.云南白秧坪银铜多金属矿集区碳氧同位素组成及其意义[J].矿床地质, 23(1):1~8.
    刘家军,毛光剑,吴胜华等. 2010.甘肃礼县-岷县成矿带西段寨上金矿床中自然金的发现及成因意义[J].地质通报, 29(1):115~23.
    连玉,徐文艺,杨丹等.2008.西藏冈底斯甲马和南木矿床流体包裹体SR-XRF研究[J].岩石矿物学杂志.Vol.27,No.3(185~198)
    孟祥金,候增谦,李振清.2006.西藏驱龙斑岩铜矿S、Pb硫铅同位素组成:对含矿斑岩与成矿物质来源的指示[J].地质学报,80(4):554~562.
    毛晓冬,黄思静.2002.长坑-富湾金、银矿床硫同位素组成特征及其意义[J].华南地质与矿产,(1):17~22.
    潘风雏.2001.西藏甲马喷流交代夕卡岩型铜多金属矿床成矿模式.中国地质大学(北京).硕士学位论文
    潘凤雏,邓军,姚鹏等.2002.西藏甲马铜多金属矿床夕卡岩的喷流成因[J].现代地质,16(4):
    潘风雏,粟登奎,姚鹏等.1997.西藏甲马喷流夕卡岩型铜多金属矿床地质特征[J].西藏地质,18(2):62~73
    彭勇民,姚鹏,李金高.2001.西藏甲马铜多金属矿区上侏罗统一白垩系层序地层与成矿[J].地质论评,47(6):584~589
    秦志鹏.2010.西藏甲玛铜多金属矿床似埃达克岩的成岩成矿作用.成都理工大学.硕士学位论文
    曲晓明,候增谦,李佑国.2002.S、Pb同位素对冈底斯斑岩铜矿带成矿物质来源和造山带物质循环的指示[J].地质通报,21(11):768~776.
    曲晓明,侯增谦,黄卫.2001.冈底斯斑岩铜矿(化)带:西藏第二条“玉龙”铜矿带? [J].矿床地质,20(4):355~366
    任云生,粟登逵,张金树.2002.西藏甲马铜多金属矿床金的叠加成矿[J].吉林大学学报(地球科学版),32(3):225~228
    芮宗瑶,侯增谦,曲晓明等.2003.冈底斯斑岩铜矿成矿时代及青藏高原隆升[J].矿床地质,22(3):217~225
    唐菊兴,王登红,汪雄武等.2010.西藏甲玛铜多金属矿矿床地质特征及其矿床模型[J].地球学报,31(4):495~506
    于津生,李耀菘. 1997.中国同位素地球化学研究[M].北京:科学出版社,1997:314-409.
    王全海,王保生,李金高等.2002.西藏冈底斯岛弧及其铜多金属矿带的基本特征与远景评估[J].地质通报,2l(1):35~40
    王万顺,路彦明,向永生等.2001.西藏班公湖-怒江成矿带中段金矿资源评价〔R〕.河北廊坊:武警黄金地质研究所,
    姚鹏,顾雪祥,李金高等.2006.甲马铜多金属矿床层控夕卡岩流体包裹体特征及其成因意义[J].成都理工大学学报(自然科学版),2006a 33 (3):285~293
    姚鹏,李金高,顾雪祥等.2006.从REE和硅同位素特征探讨西藏甲马矿床层状夕卡岩成因[J].岩石矿物学杂志,2006b 25(4):303~3l3
    姚鹏,杜光树.1999.西藏甲马多金属矿床容矿岩石的地球化学特征及其成因初步研究[J].特提斯地质,(23):46~57
    姚鹏,郑明华,彭勇民等.2002.西藏冈底斯岛弧带甲马铜多金属矿床成矿物质来源及成因研究[J].地质论评,48(5):468~479
    杨时惠.1995.西藏甲马赤康多金属矿床金银钴铋镍赋存状态及其矿物学特征研究[J].矿物岩石,15(1):26~34
    应立娟,唐菊兴,王登红等.2009.西藏甲玛铜多金属矿床矽卡岩中辉钼矿铼-锇同位素定年及其成矿意义[J].岩矿测试. 28(3):265~268.
    袁万明,侯增谦,李胜荣等.2001.西藏甲马多金属矿区热历史的裂变径迹证据[J].中国科学(D辑),3l:l17~121
    赵一鸣,林文蔚,毕承思,等.中国含金夕卡岩矿床的分布和主要地质特征[J].矿床地质, 1997b,16(3):193-203.
    赵一鸣,张轶男,毕承思. 1997.含金夕卡岩矿床产出构造环境和地质地球化学评价标志[J].地学前缘,1999b,6(1):181-193.
    赵一鸣.夕卡岩矿床研究的某些重要新进展[J].矿床地质,2002,21(2):113-120.
    郑文宝,陈毓川,宋鑫等.2010.西藏甲玛铜多金属矿元素分布规律及地质意义[J].矿床地质. Vol.29,No.5:775~784
    郑文宝,陈毓川,唐菊兴等.2010.西藏甲玛铜多金属矿床铜矿化富集规律研究及应用[J].金属矿山,404(2):87~91
    张理刚.1985.稳定同位素在地质科学中的应用[M].西安:陕西科学技术出版社.152~185.
    郑永飞,陈江峰.2000.稳定同位素地球化学[M].北京:科学出版社.143~245.
    朱训,黄崇轲,芮宗瑶等.1983.德兴斑岩铜矿〔R〕.北京:地质出版社
    朱炳泉等.1998.地球科学中同位素体系理论与应用-兼论中国大陆壳幔演化[M].北京:科学出版社.216~230.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700