南秦岭平利地区成矿构造地质条件及找矿远景研究
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
本文依托南秦岭平利地区南北4幅1:5万矿产远景调查,在充分搜集研究前人资料的基础上,通过野外实际路线和矿点调查及重要样品实验测试研究,重点对平利地区的区域地质和矿产特征、重要矿化类型及成矿特点进行了研究,探索了以花桥钛磁铁矿为代表的重要成矿类型,并研究分析了平利地区主要矿化类型的找矿远景。取得了以下主要成果和进展。
     1.平利地区地处扬子陆块与秦岭造山带结合部位,主要出露有基底中元古界杨坪组,由绢云绿泥片岩和绢云钠长片岩等组成,上覆有南华系耀岭河组的变质火山岩系、震旦系陡山沱组的碳硅质板岩和灯影组白云质灰岩等,早古生代主要沉积了一套被动大陆边缘还原相的硅质岩、灰岩和碳质板岩等,自泥盆纪以后地层缺失;区内岩浆作用微弱,岩浆岩出露有限,主要发育有南华系基性火山岩和奥陶纪碱性辉长岩类两期岩浆事件,分别代表Rodinia超大陆裂解在秦岭地区的响应和早古生代大陆板内构造—岩浆事件。现有构造和地形地貌是印支期构造运动的结果。
     2.平利地区整体矿化较弱,仅发现有一些工作程度较低的矿点、矿化点,主要成矿类型为与奥陶纪碱性辉长岩类有关的岩浆分异型钛磁铁矿,产于震旦纪灯影组灰岩中的MVT型铜铅锌矿和主要分布于寒武纪鲁家坪组碳硅质岩中的沉积改造型钒钼矿等。其中,钛磁铁矿有较好找矿远景,已发现有中小型成矿潜力的花桥矿点;产于灯影组灰岩中的铜铅锌矿化,区域成矿分析与扬子北缘MVT型铅锌矿处于同一层位,可能是该类型矿产在本研究区的表现,但研究区产于灯影组灰岩中的罗家院子矿点,以铅锌含量较低(0.01—1.68%),铜含量高(2.56—17.25%)为特点,与区域上扬子型MVT铅锌矿在矿种上有显著差异;寒武系中的钒钼矿目前尚未见有工业意义的矿化,可能是成矿元素富集不足。
     3.花桥钛磁铁矿作为区域上较有价值的与碱性辉长岩类有关的金属成矿类型,本论文进行了较为深入的研究。花桥钛磁铁矿可见赋矿岩体长约250m,宽8—10m,面积约2500m~2,岩体呈透镜体状,岩石类型主要为辉石岩、辉长岩等,主要含矿岩相为黑云母辉石岩,岩石主要由含钛普通辉石组成,其次为黑云母。含钛普通辉石呈自形一半自形晶,见微量磷灰石和榍石,岩石绿泥石化、碳酸盐化明显。钛磁铁矿体产于岩体中部,与岩体呈过渡关系,无清楚界线,矿石主要为稠密浸染状,主要金属矿物为钛磁铁矿、钛铁矿、磁铁矿和少量黄铁矿。
     4.花桥钛磁铁矿赋矿岩石岩石地球化学全碱—硅图解投图,主要落入碱性辉长岩中,但与一般碱性辉长岩相比,SiO_2较低,已获样品SiO_2在42.82—44.95(wt%)之间,Na20>K_2O,Na_2O/K_2O在2.56—5.26之间,属典型钠质型碱性岩类;MgO含量5.32—6.74%,TiO_2为3.82—5.84%,Al_2O_3为13.27—15.06%;m/f比值为0.37—0.56,属富铁质系列。Pearce(1977)的FeO—MgO—Al_2O_3图解,落入大陆板内。稀土元素总量较高,∑REE为157.60—336.63×10~(-6),呈显著轻稀土富集特点,(La/Yb)N=10.13—18.88,δEu为1.51—2.13,铕呈轻微正异常。矿石矿物钛磁铁矿TiO_2含量0.415—23.69%,FeO含量69.7—96.18%,Cr_2O_3含量0.062—0.761%。上述特征表明研究区钛磁铁矿是扬子陆块北缘早古生代幔源低程度部分熔融产物上侵分凝成矿作用结果。
     5.平利地区南北长80余公里,东西宽20余公里,约1700km~2范围内,运用综合分析方法,对岩浆分异型钛磁铁矿、MVT型铜铅锌矿和沉积改造型钒钼矿找矿远景进行预测。钛磁铁矿以碱性辉长岩类矿化,特别是辉石岩的产出为有利找矿标志,有明显磁异常和Ti元素地球化学异常,在研究区共圈出3个找矿远景区,以花桥远景区最具找矿前景;MVT型铜铅锌矿,主要找矿标志为震旦纪白云质灰岩及后期构造裂隙发育为典型特征,Cu、Pb、Zn元素地球化学异常为重要找矿指示,在研究区圈出6个找矿远景区,其中以罗家院子远景区最具找矿潜力。
On the basis of 4 one to fifty thousand of mineralization and prospective survey in Pingli area in South Qinling,the author collected and researched many datas of the the former geological workers in the area,and then through investigating field routes and ore occurrences and testing on important samples,especially researched the characters of regional geology,mineralization,important mineralization types in Pingli area.And quest for the important mineralization types which representative of Huaqiao titanomagnetite occurrence in the research area,then analyse and predicate the ore deposit of the major mineralization types in Pingli area.The major inclusion and advances as follows.
     1.The Pingli area is located in the region of the joints of Yangtze block and Qinling orogenic belt.The outcrops are mainly fundus of Yangping Group of Middle Algonkian, which is composed of sericite chlorite-schist and sericite albite-schist.The roof rock consist of metamorphic lava of Nanhuaan System,Doushantuo Group carbonaceous-siliceous rocks and Dengying Group dolomitic-limestone of Sinian Period,and a set of siliceous rocks, limestone and carbonaceous slate in deoxidize environment on the edge of passive continental margin in Early Paleozoic.And the strata were lost began from Devonian.The magmatism were faint and the magmatic rock are exiguous exposed in the Pingli area,and mainly developed two times of magma events of basic lava of Nanhuaan System and alkaline-gabbro of Ordovician,The basic lava of Nanhuaan System represents the corresponding to the breakup of the Rodinia super-continent in Qinling,and the alkaline gabbro of Ordovician represents the intracontinental tectonic- magmatism in Early Paleozoic.
     2.The mineralization is faint in the whole Pingli area,and only found some mineralization occurrences which were inadequate exploration in this area.The main mineralization types of them are Magmatic Differentiation-type of titanomagnetite occurrence related to the alkaline-gabbro of Ordovician,the MVT-type of Cu-Pb-Zn mineralization produced in the Dengying Group dolomitic-limestone of Sinian Period and the Sedimentary Reformation-type of V-Mo mineralization mainly distributed in the Lujiaping Group carbonaceous-siliceous rocks of Cambrian et al.The titanomagnetite occurrence has the long-range view in these mineralization types and it has found the Luojiayuanzi Cu-Pb-Zn ore occurrence,which has the long-term view of becoming small-middle sized deposit.According to the regional mineralization analysis,the Cu-Pb-Zn mineralization occurs in the Dengying Group limestone is found in the same strata horizon to the MVT-type of Cu-Pb-Zn mineralization in the edge of Yangtze block,it maybe the behaviour of MVT-type of Cu-Pb-Zn mineralization in Pingli area.But the Luojiayuanzi is characterd by low-grade of Pb/Zn(0.01—1.68%),high-grade of Cu(2.56—17.25%),it is different to the ore of MVT-type mineralization.It hasn't found economic value of V-Mo mineralization in the Cambrian system,it is probably because of the inadequate enrichment of mineralization elements.
     3.Huaqiao titanomagnetite occurrence,as has the economic value of the metal mineralization type related to the alkaline-gabbro in the region,the author made embedded study on it.The visible ore-body of Huaqiao titanomagnetite occurrence is about 250m long and 8—10m wide,and the area is about 2500m~2.It was lens shape,and the ore type are mainly pyroxenite and gabbro et al.The ore-bearing lithofacies is biotite- pyroxenite.The rock mainly consists of titaniferous-pyroxene,the others is biotite.In the rock the titaniferous-pyroxene is automorphic-hypautomorphic,and there is a little of apatite and sphene in it.The chloritization and carbonatization are distinct in the rock.The titanomagnetite occurrence is occured in the middle part of the pyroxenite body,and is gradual changed of no obvious borderline between the ore body and the country rocks.The ore is mainly of dense-disseminated and consists of titanomagnetite,mohsite,magnetite and little pyrite.
     4.The petrogeochemistry of Whole alkali-Silicon schema of Huaqiao titanomagnetite occurrence reveals it is in the alkaline-gabbro range,but it has lower content of SiO_2 than the common gabbro,the SiO_2 is 42.82—44.95(wt%) of the now get samples.The Na_2O>K_2O, (Na_2O/K_2O = 2.56—5.26),so that it is typical natrium-type alkali rock.MgO = 5.32—6.74%,TIO_2 = 3.82—5.84%,Al_2O_3 = 13.27—15.06%.The value of m/f= 0.37—0.56,then it is belongs to Fe-rich rock series.The FeO—MgO—Al_2O_3 schema(Pearce,1977) of the samples' data revels it is within the continent.The∑REE = 157.60—336.63×10~(-6),shows the LREE-rich character.(La/Yb)_N =10.13—18.88.δEu =1.51—2.13,display a faint positive anomaly trend of Eu.The TIO_2=0.415—23.69%,FeO = 69.7—96.18%,Cr_2O_3 = 0.062—0.761%of the titanomagnetite.All the characters above show that the titanomagnetite occurrence is the result of magmatic segregation when the low-degree of partly fusing outcome of mantle origin in the north edge of the Yangtze block in the early Paleozoic.
     5.The investigation area of this paper is about 80 km long and 20 km wide,the area is about 1700km~2.Through the integrate analysis,the author predicate the prospective ore deposit to the Magmatic Differentiation-type of titanomagnetite mineralization,the MVT-type of Cu-Pb-Zn mineralization and the Sedimentary Reformation-type of V-Mo mineralization.It suggest in this paper that the mineralization of alkaline-gabbro,spatially the emergence of pyroene is the effective symbol indicating the titanomagnetite mineralization,and there are distinct magnetic and Ti petrogeochemistry abnormity,and predict 3 prospective zones,the Huaqiao zone is the best one.The major orefinding symbols of MVT-type of Cu-Pb-Zn mineralization are dolomitic-limestone of Sinian Period and development of Later tectonic break,and the Cu/Pb/Zn petrogeochemistry abnormity are important oresearch indicator,and predict 6 prospective zones,the Luojiayuanzi zone is the best one.
引文
陈孝德,史兰斌.伸展构造中德基性岩墙.见钱祥麟主编.伸展构造研究.北京:北京地质出版社,1994,56-89
    程裕淇等,杨遵仪,王泽九等.中国地层典.第四分册(新元古界),1996:25-97;第五分册(寒武系),1996:16-75;第七分册(志留系),1996:30-83
    邓晋福,赵海铃,莫宣学等.中国大陆根-柱构造-大陆动力学的钥匙.北京:地质出版社,1996,175-190
    段成龙.试论攀枝花式铁矿的成因问题.四川冶金,2000,(3):1-5
    范德廉,叶杰,杨瑞英等.扬子地台前寒武-寒武纪界线附近的地质事件及成矿作用.沉积学报,1987,5(3):72-103
    范德廉,张焘,叶杰等.中国的黑色岩系及其有关矿床.北京:科学出版社,2004,1-141
    高长林.中国内蒙古中部和陕南东部两类古大陆边缘的地球化学研究.武汉:中国地质大学出版社,1993.3-91
    国土资源网.江西:要主攻“扬子型”铅锌矿床.http://news.mlr.gov.cn/front/chinaResource/read/news-info.asp?ID=108665,2007-03-17/2007-05-08
    胡健民等,赵国春,孟庆任等.武当地块基性侵入岩群的地质特征与构造意义.岩石学报,2003,19(4):601-611
    胡素芳,周新华.镁铁-超镁铁层状侵入体研究现状.矿物岩石地球化学通报,2001,(1):52-57
    黄汲清,任纪舜等.中国大地构造演化.北京:科学出版社,1980,12-189
    黄月华,任有祥,夏林圻等.北大巴山早古生代双模式火山岩套:以高滩辉绿岩和嵩坪粗面岩为例.岩石学报,1992,8(3)243-256
    黄月华.岚皋碱性镁铁-超镁铁质潜火山杂岩中金云角闪辉石岩类地幔捕虏体矿物学特征.岩石学报,1993,19(4)367-378
    林长谦,温礼琴,马文胜.湖北竹溪-谷城一带铅锌矿地质特征及找矿方向[J].资源环境与工程,2005,(02):33-37
    刘淑文.南秦岭古生代盆地演化中幕式流体成岩成矿作用研究.西安:长安大学,2006:9-14
    刘文均.我国东部地区产于碳酸盐岩中层控铅锌矿床的区域特点[J].矿床地质,1984,3(3):38-46
    刘英俊,曹励明,李兆麟等.元素地球化学.北京:科学出版社,1984,6-415
    龙宝林,刘忠明.鄂西地区铅锌矿基本特征与找矿方向[J].地质与勘探,2005,(03):45-52
    马润华,伊鸥英等.陕西省岩石地层.中国地质大学出版社,1998:1-144
    齐文,侯满堂,汪克明等.陕西南郑县马元一带发现大型层控型铅锌矿带.地质通报,2004,23(11):1139-1142
    邱家骧,林景仟主编.岩石化学换算方法.北京:地质出版社.1993,6-276
    邱家骧等.秦巴碱性岩.北京:地质出版社,1993,5-42
    阙梅英,罗安屏,张立生等.滇东北上震旦一下寒武统层控铅锌矿.成都:成都科技大学出版社,1993, 1-186
    芮宗瑶,李宁,王龙生.关门山铅锌矿床:盆地热卤水成矿及铅锌同位素打靶.北京:地质出版社,1991,3-134
    芮宗瑶,叶锦华,张立生等.扬子克拉通周边及其隆起边缘的铅锌矿床.中国地质,2004,31(4):337-346
    宋谢炎,马润刚,王玉兰等.攀枝花层状侵入体韵律层理及岩浆演化特征.矿物岩石,1994,14(4):37-45
    宋谢炎,马润则,王玉兰,张正阶.攀枝花层状侵入体韵律层理及岩浆演化特征[J].矿物岩石,1994,(04).37-45
    唐纳W,海因德曼.火成岩与变质岩石学(上册).邱家骧,王方正,耿小云等译.武汉:中国地质大学出版社,1985,165-188
    陶洪祥,何恢亚,王全庆,裴先治.扬子板块北缘构造演化史.西安:西北大学出版社,1993:1-7,110-125
    王根宝,冯华,焦建宏.论南秦岭加里东运动.陕西地质,1998:16(1):11-16
    王中刚,于学元,赵振华等.稀土元素地球化学.北京:科学出版社.1989,17-276
    吴利仁,徐贵忠.东秦岭-大别山碰撞造山带的地质演化.北京:科学出版社,1998:252-260
    吴仁利.论中国基性超基性岩的成矿专属性.中国地质学会三十二届年会论文选.矿物/岩石/地化部分.1963
    夏林圻,夏祖春,徐学义.秦岭中晚元古代火山岩性质与前寒武纪大陆裂解.中国科学(D辑),1996,26(3):237-243
    夏林圻,夏祖春等.祁连、秦岭山系海相火山岩.武汉:中国地质大学出版社,1991,5-311
    夏祖春,夏林圻,张城.北大巴山碱质基性-超基性潜火山岩的辉石矿物研究.西北地质科学,1992,13(2):22-30
    肖振民,叶水泉,钟庆禄等.南京栖霞山铅锌银矿床地质及勘查模式.北京:地质出版社,1996,1-98
    晏云翔.陕西紫阳-岚皋地区碱-基性岩墙群的岩石地区化学及Sr、Nd、Pb同位素地球化学研究,西安:西北大学,2005
    杨应选,柯成熙,林方成等.康滇地轴东缘铅锌矿床成因及成矿规律.成都:四川科学技术出版社,1994,1-181
    袁见齐,朱上庆,翟裕生.北京:地质出版社.矿床学,1985,13-98
    张本仁,高山,张宏飞,韩吟文.秦岭造山带地球化学.北京:科学出版社,2002,100-101
    张本仁主编,秦巴岩石圈构造及成矿规律地球化学研究,中国地质大学出版社,1994,12-121
    张成立,高山,张国伟等.秦岭早古生代碱性岩墙群的地球化学及其地质意义.中国科学(D辑),2002,32(10):819-829
    张二朋,牛道韫,霍有光等.秦巴及邻区地质构造特征概论.北京:地质出版社,1993,263-271
    张二朋,杨应章编.西北地区重要成矿带基础地质综合研究项目成果报告.西安地质矿床研究所,2006
    张国伟,柳小明.关于“中央造山带”几个问题的思考.地球科学-中国地质大学,1998,23(5):443-448
    张国伟,梅志超,李桃红.秦岭造山带南部被动大陆边缘.见张国伟等《秦岭造山带的形成及其演化》.西安:西北地质大学出版社,1988,32-112
    张国伟,孟庆任,赖绍聪.秦岭造山带结构构.中国科学(B辑),1995,25(9):994-1003
    张国伟,张本仁,袁学诚,肖庆辉等.秦岭造山带与大陆动力学.北京:科学出版社,2001.130-150,430-431
    张立生.康滇地轴东缘以碳酸盐岩为主铅锌矿床的几个地质问题.矿床地质,1998,17(增刊):135-178
    周朝宪,魏春生,叶造军.密西西比河谷型矿床.地质地球化学,1997,(1):69-75
    周鼎武,张成立,王居里等.武当地块基性岩墙群初步研究及其地质意义.科学通报,1997,2(23):2546-2549
    Anderson G M.Preeipititation of Mississippi valley-type ores[J].Econ.,Geol.,1975,70(5):737-942
    Andersson A,Dahlman B,Gee D G et al.The Scandinavian Alum Shales.Avhandlingar OCH Uppsatser 1A4,Ser.Ca NR,56:2-68
    Bateman,A.M.The formation of late magmatic oxide ores.Econ,Geol.,1951,Vol.46.p.404-26.
    Giordano T H,Barres H L.Lead transport in Mississippi valley-type ore solutions[J].Econ.,Geol.,1981,76(8):2200-2211
    Haynes F M and Kesler S E.Chemical evolution of brines during Mississippi valley-type mineralization:evidence from east Tennessee and Pine Point[J].Econ.,Geol.,1987,82(1):53-71
    Lindgren W.Au and Ag in shales from Western Kansas.U.S Geol.Surv.Bull.,1902,202:21
    Melimans R K,Barnes H L,Ohmoto H.Sphalerite stratigraphy of the upper Mississippi valley-type zinc-lead district,southwest Wisconsin[J].Econ.,Geol.,1985,80(6):1736-1752
    Ohle E L.Some considerations in determining the origin of ore deposits of the Mississippi valley-type-part Ⅱ[J].Econ.Geol.,1980,75(2)161-172
    Pirojno Franco.Ore deposits and mantle plumes.Landon:Klawer Academic Publishers.2000,1-540.
    Rdedder E.Fluid inclusion studies of ore deposits in the Viburnum trend,Southeast Missouri[J].Econ.,Geol.,1977,72(3):474-479
    Sangter D F.层控赋金属矿床及其成矿作用[J].国外矿床地质,1985(增刊):1-99
    Sverjensky D A,Oil field brines as ore-forming solution[J].Econ.Geol.1984,79(1):23-37
    Sverjensky D A,Rye D M,Doe B R.The lead and sulfide isotopic compositions of galena from a Mississippi Valley-type deposit in the New lead belt,Southesast Missouri[J].Econ.,Geol.,1979,74(1):149-153
    Sverjensky D A.Genesis of Mississippi valley-type lead-zinc deposits[J].Annual Review of Earth and Planetary Science,1986,14:177-199
    Sverjensky D A.The distribution of divalent trace elements between sulfides,Oxides,silicates and hydrothermal solutions:1:themodynamic basis[J].Geochimiea Acta,1985,49(3):853-864
    Willson M.Igneous petrogenesis.London:Allen and Unwin,1989
    Windley BF.进化中的大陆.赵锡文,杜宽平,赵福堂等译.武汉:中国地质大学出版社,1989,32-166
    Zhao Chaoxian,Wei chunsheng,Gao jijun,etal.The source of metals in the Qilinchang Zn-Pb deposit,Northeastern Yunnan,China:Pb-Sr isotope constraints.[J].Econ.,Geol.,2001,96(7):583-598

© 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