本文主要研究内容
作者鲍佩声(2019)在《元古代蛇绿岩及铬铁矿》一文中研究指出:本文总结了国外典型元古代蛇绿岩的岩石组合、野外产状、地球化学资料以及成矿特征,并与显生宙蛇绿岩进行了对比,继而探讨元古代板块构造演化和铬铁矿成因。资料表明,早元古代和中-新元古代均有蛇绿岩的存在,但前者较少,仅见于Canadian地盾的Cape Smith Belt中的Prutuniq蛇绿岩(2. 05~2. 0Ga)和芬兰Fennoscandian地盾的Outokumpu和Jormua蛇绿岩(时代为1. 97~1. 96Ga),而中-新元古代的蛇绿岩则见于世界许多地区,如埃及东部沙漠区(~750Ma)和非洲东北部地区(ca.900~800Ma)等。与显生宙蛇绿岩相比,这些老蛇绿岩具如下特征:(1)它们均为被肢解的蛇绿岩,大多与"弧火山岩"和(或)混杂岩伴生,经历不同程度的变形和变质(具绿片岩相-角闪岩相组合);(2)岩石组合大多较齐全,壳层组合发育,以镁铁-超镁铁岩(堆晶岩)、辉长岩、镁铁质席状岩床(墙)杂岩、火山岩为代表;层状镁铁-超镁铁岩的韵律层以及矿物的隐晶变化等均提示了岩浆多期次活动及开放岩浆房的特征;(3)元古代蛇绿岩中既有高铝型铬铁矿,也有高铬型铬铁矿,且主要寄主于纯橄岩(或蛇纹岩)中;高铝型和高铬型直接受控于熔体的熔融程度及含水流体的参与,反映了铬铁矿形成于俯冲带演化的不同阶段;铬铁矿规模均较小,且均以低TiO 2为特征,均为岩浆分异作用的产物,明显区别于显生宙熔融残余成因的豆荚状铬铁矿;(4)元古代蛇绿岩常伴有硫化物Cu-Co-Zn-Au矿,且铬铁矿含Zn较高(Zn=0. 11%~0. 18%)(如芬兰Outokumpu蛇绿岩);橄榄岩及铬铁矿中常含较高的MnO (高达1. 79%,如埃及东部的Wizer蛇绿岩);(5)元古代蛇绿岩具多种成因:主要为俯冲带成因(如埃及蛇绿岩、北东非蛇绿岩、芬兰Outokumpu蛇绿岩),少量为洋中脊成因(加拿大Purtuniq蛇绿岩)及裂谷成因(芬兰Jormua蛇绿岩)等。
Abstract
ben wen zong jie le guo wai dian xing yuan gu dai she lu yan de yan dan zu ge 、ye wai chan zhuang 、de qiu hua xue zi liao yi ji cheng kuang te zheng ,bing yu xian sheng zhou she lu yan jin hang le dui bi ,ji er tan tao yuan gu dai ban kuai gou zao yan hua he ge tie kuang cheng yin 。zi liao biao ming ,zao yuan gu dai he zhong -xin yuan gu dai jun you she lu yan de cun zai ,dan qian zhe jiao shao ,jin jian yu Canadiande dun de Cape Smith Beltzhong de Prutuniqshe lu yan (2. 05~2. 0Ga)he fen lan Fennoscandiande dun de Outokumpuhe Jormuashe lu yan (shi dai wei 1. 97~1. 96Ga),er zhong -xin yuan gu dai de she lu yan ze jian yu shi jie hu duo de ou ,ru ai ji dong bu sha mo ou (~750Ma)he fei zhou dong bei bu de ou (ca.900~800Ma)deng 。yu xian sheng zhou she lu yan xiang bi ,zhe xie lao she lu yan ju ru xia te zheng :(1)ta men jun wei bei zhi jie de she lu yan ,da duo yu "hu huo shan yan "he (huo )hun za yan ban sheng ,jing li bu tong cheng du de bian xing he bian zhi (ju lu pian yan xiang -jiao shan yan xiang zu ge );(2)yan dan zu ge da duo jiao ji quan ,ke ceng zu ge fa yo ,yi mei tie -chao mei tie yan (dui jing yan )、hui chang yan 、mei tie zhi xi zhuang yan chuang (qiang )za yan 、huo shan yan wei dai biao ;ceng zhuang mei tie -chao mei tie yan de yun lv ceng yi ji kuang wu de yin jing bian hua deng jun di shi le yan jiang duo ji ci huo dong ji kai fang yan jiang fang de te zheng ;(3)yuan gu dai she lu yan zhong ji you gao lv xing ge tie kuang ,ye you gao ge xing ge tie kuang ,ju zhu yao ji zhu yu chun gan yan (huo she wen yan )zhong ;gao lv xing he gao ge xing zhi jie shou kong yu rong ti de rong rong cheng du ji han shui liu ti de can yu ,fan ying le ge tie kuang xing cheng yu fu chong dai yan hua de bu tong jie duan ;ge tie kuang gui mo jun jiao xiao ,ju jun yi di TiO 2wei te zheng ,jun wei yan jiang fen yi zuo yong de chan wu ,ming xian ou bie yu xian sheng zhou rong rong can yu cheng yin de dou jia zhuang ge tie kuang ;(4)yuan gu dai she lu yan chang ban you liu hua wu Cu-Co-Zn-Aukuang ,ju ge tie kuang han Znjiao gao (Zn=0. 11%~0. 18%)(ru fen lan Outokumpushe lu yan );gan lan yan ji ge tie kuang zhong chang han jiao gao de MnO (gao da 1. 79%,ru ai ji dong bu de Wizershe lu yan );(5)yuan gu dai she lu yan ju duo chong cheng yin :zhu yao wei fu chong dai cheng yin (ru ai ji she lu yan 、bei dong fei she lu yan 、fen lan Outokumpushe lu yan ),shao liang wei xiang zhong ji cheng yin (jia na da Purtuniqshe lu yan )ji lie gu cheng yin (fen lan Jormuashe lu yan )deng 。
论文参考文献
论文详细介绍
论文作者分别是来自岩石学报的鲍佩声,发表于刊物岩石学报2019年10期论文,是一篇关于元古代论文,蛇绿岩论文,铬铁矿论文,构造环境论文,岩石学报2019年10期论文的文章。本文可供学术参考使用,各位学者可以免费参考阅读下载,文章观点不代表本站观点,资料来自岩石学报2019年10期论文网站,若本站收录的文献无意侵犯了您的著作版权,请联系我们删除。
标签:元古代论文; 蛇绿岩论文; 铬铁矿论文; 构造环境论文; 岩石学报2019年10期论文;