重庆市巫山县桃花铁矿地质特征分析
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摘要
重庆市巫山县桃花铁矿大地构造位置处于扬子准地台上扬子台坳渝东南陷褶束七曜山凹褶束。矿区位于七曜山背斜北东段南东翼之次级褶皱贺家坪背斜北东段。矿床产于上泥盆统黄家磴组灰绿色、紫色粉砂质页岩中。矿体顶、底板围岩与矿体界线清楚,矿体呈层状至似层状产出。矿石矿物以赤铁矿为主,其次菱铁矿,占90%左右;脉石矿物主要有石英、水云母、鲕绿泥石、胶磷矿等,含量少许。杂质元素磷主要以胶磷矿形态赋存于铁矿石中,常呈细小团块分布在赤铁矿中,有时也和赤铁矿一起形成圈层的鲕粒。全矿区矿石平均品位达TFe43.58%,有害成分磷含量为0.5～1.1%之间,总体较高,致使本矿区矿石为高磷鲕状赤铁矿矿石。本区矿石结构主要有豆鲕粒状结构及鲕砂状结构,矿石构造主要有条带状构造及块状构造。
本矿床的形成主要受岩相古地理条件控制。本文总结出了对形成沉积铁矿床有利的岩相古地理条件:①湿热的古气候条件,促使古陆的含铁岩石进行红土化作用,并提供充足的铁质来源。②相对较封闭或半封闭的内陆古海盆地、古海湾,在这里海水深度不大,且较平静,无海洋大风大浪的侵袭,有利于铁矿沉积作用的进行。③浅海的海侵沉积岩系中,一般形成鲕状赤铁矿矿石相。④铁质可能主要是以胶体、细悬浮凝胶或呈吸附的氧化物形式被古陆的河流进行搬运的。本区位于鄂西-湘西北成矿区。鄂西-湘西北成矿区属于一个相对较封闭的内陆古海盆地,海水比较平静,有利于铁矿沉积作用的进行。
成矿主要物质铁质主要来自周围受风化的古陆。近滨相完全具有建鲕条件,加上含有丰富的核心材料,在悬浮状态下,各种赤铁矿泥晶等围绕核心以胶体化学方式发生沉积形成赤铁矿鲕粒。形成的赤铁矿鲕粒经过波浪和潮汐水流的再次搬运改造与富集,最终就位于近滨相至远滨相上部环境,形成“宁乡式”铁矿床。
本矿区赤铁矿矿床的成因类型系同生沉积成因,鲕状赤铁矿以胶体化学沉积方式形成。
The geotectonic location of Taohua mining area of Wushan in Chongqing lies in Qiyaoshan arcuate-folded area in Southeast Chongqing depression-folding beam of upper Yangtze Syneclise of Yangtze para-platform.Mining area lies in NE end at Hejiaping anticline belonging to secondary fold of SE wing at Qiyaoshan anticline.The deposit is hosted in grey green and violet silty shale in the Huangjiadeng Formation of upper devonian.The orebody has a clear demarcation with the roof and bottom of orebody,and is occurred in form of stratiform and stratiform-like.Ore minerals which are about 90% in ores mostly contain hematite and siderite secondly;Gangue minaerals that have a low content in ores mostly contain quartz and hydromica and chamosite and collophanite.Impurity P mainly occurs in form of collophanite in iron ores,which usually distributes in hematite ores by form of fine briquettes and sometimes forms oolites of circle layer with hematites.The average grade of ores in mining area reaches TFe43.58%.The content of harmful component P is 0.5～1.1%,which is generally quite high.As a result,ores in this mining area become oolitic hematite ores containing high P.Ores texture mostly are pisolitic-oolitic and oolitic-sandy.Ores structure mostly are banding and massive.
The formation of iron deposit mainly is controlled by the condition of lithofacies- paleogeography.This paper summarizes the condition of lithofacies-paleogeography that is beneficial to form iron deposit:①Paleoclimate condition of damp-heat impels laterization of rocks containing iron on ancient land,which provides adequate iron source;②In ralatively quite closed or semi-closed inland furumi basin and ancient coastal bay,because of their sea depth are ralative shallow,the condition of no great storms is useful for sedimentation of iron deposit;③Generally speaking,the transgression sedimentary series of shallow sea are helpful for oolitic hematite ore facies;④The iron may be mainly transported in the form of colloids and fine suspended gels or adsorbing oxides by the ancient land rivers.This area lies in metallogenic province of Western Hubei and Northwestern Hunan,which belongs to a relatively quite closed inland furumi basin and has useful condition of no invasion of great sea storms and quiet sea for sedimentation of iron deposit.
The main metallogenic material Fe mostly comes from around ancient land weathered.Nearshore facies totally have the condition of building oolites,superadd containing abundant core materials.At state of suspending,various hematite micrites form hematite oolites in methods of collochemistry sedimentary.After being transformed and enriched by sea wave and tide process,these oolites form the Ningxiang-type iron deposit which is finally believed to belong to nearshore facies and upper offshore facies.
The genetic type of hematite deposit belongs to syngenetic deposit.Oolitic hematites are formed by collochemistry sedimentary.
本矿床的形成主要受岩相古地理条件控制。本文总结出了对形成沉积铁矿床有利的岩相古地理条件:①湿热的古气候条件,促使古陆的含铁岩石进行红土化作用,并提供充足的铁质来源。②相对较封闭或半封闭的内陆古海盆地、古海湾,在这里海水深度不大,且较平静,无海洋大风大浪的侵袭,有利于铁矿沉积作用的进行。③浅海的海侵沉积岩系中,一般形成鲕状赤铁矿矿石相。④铁质可能主要是以胶体、细悬浮凝胶或呈吸附的氧化物形式被古陆的河流进行搬运的。本区位于鄂西-湘西北成矿区。鄂西-湘西北成矿区属于一个相对较封闭的内陆古海盆地,海水比较平静,有利于铁矿沉积作用的进行。
成矿主要物质铁质主要来自周围受风化的古陆。近滨相完全具有建鲕条件,加上含有丰富的核心材料,在悬浮状态下,各种赤铁矿泥晶等围绕核心以胶体化学方式发生沉积形成赤铁矿鲕粒。形成的赤铁矿鲕粒经过波浪和潮汐水流的再次搬运改造与富集,最终就位于近滨相至远滨相上部环境,形成“宁乡式”铁矿床。
本矿区赤铁矿矿床的成因类型系同生沉积成因,鲕状赤铁矿以胶体化学沉积方式形成。
The geotectonic location of Taohua mining area of Wushan in Chongqing lies in Qiyaoshan arcuate-folded area in Southeast Chongqing depression-folding beam of upper Yangtze Syneclise of Yangtze para-platform.Mining area lies in NE end at Hejiaping anticline belonging to secondary fold of SE wing at Qiyaoshan anticline.The deposit is hosted in grey green and violet silty shale in the Huangjiadeng Formation of upper devonian.The orebody has a clear demarcation with the roof and bottom of orebody,and is occurred in form of stratiform and stratiform-like.Ore minerals which are about 90% in ores mostly contain hematite and siderite secondly;Gangue minaerals that have a low content in ores mostly contain quartz and hydromica and chamosite and collophanite.Impurity P mainly occurs in form of collophanite in iron ores,which usually distributes in hematite ores by form of fine briquettes and sometimes forms oolites of circle layer with hematites.The average grade of ores in mining area reaches TFe43.58%.The content of harmful component P is 0.5～1.1%,which is generally quite high.As a result,ores in this mining area become oolitic hematite ores containing high P.Ores texture mostly are pisolitic-oolitic and oolitic-sandy.Ores structure mostly are banding and massive.
The formation of iron deposit mainly is controlled by the condition of lithofacies- paleogeography.This paper summarizes the condition of lithofacies-paleogeography that is beneficial to form iron deposit:①Paleoclimate condition of damp-heat impels laterization of rocks containing iron on ancient land,which provides adequate iron source;②In ralatively quite closed or semi-closed inland furumi basin and ancient coastal bay,because of their sea depth are ralative shallow,the condition of no great storms is useful for sedimentation of iron deposit;③Generally speaking,the transgression sedimentary series of shallow sea are helpful for oolitic hematite ore facies;④The iron may be mainly transported in the form of colloids and fine suspended gels or adsorbing oxides by the ancient land rivers.This area lies in metallogenic province of Western Hubei and Northwestern Hunan,which belongs to a relatively quite closed inland furumi basin and has useful condition of no invasion of great sea storms and quiet sea for sedimentation of iron deposit.
The main metallogenic material Fe mostly comes from around ancient land weathered.Nearshore facies totally have the condition of building oolites,superadd containing abundant core materials.At state of suspending,various hematite micrites form hematite oolites in methods of collochemistry sedimentary.After being transformed and enriched by sea wave and tide process,these oolites form the Ningxiang-type iron deposit which is finally believed to belong to nearshore facies and upper offshore facies.
The genetic type of hematite deposit belongs to syngenetic deposit.Oolitic hematites are formed by collochemistry sedimentary.
引文
[1]中国矿业网.金属矿产资源(铁矿)[EB/OL].http://www.chinamining.com.cn/report/de fault.asp:V_DOC_ID=1059.
[2]刘树臣,马建明,崔荣国.国内外铁矿资源供需形势[EB/OL].http://xian.gov.cn/kuangchanz iyuan/2008/0819/content_1556.html.
[3]赵一鸣,毕承思.宁乡式沉积铁矿床的时空分布和演化[J].矿床地质,2000,19(4):350～361.
[4]谢家荣,孙健初,程裕淇,等.扬子江下游铁矿志[Z].地质专报,1935,甲种第13号,1～78.
[5]丁格兰.中国铁矿志(1923,上下册)[Z].谢家荣译,地质专报甲种第二号,1938,27～276.
[6]王曰伦,刘祖彝,程裕淇.湖南宁乡铁矿地质[Z].地质汇报,1938,第32号,1～32.
[7]边效曾.铁矿的普查与勘探[M].北京:地质出版社,1958,1～189.
[8]程裕淇,赵一鸣,陆松年.中国几组主要铁矿类型[J].地质学报,1978,52(4):253～268.
[9]程裕淇,陈毓川,赵一鸣,等.再论矿床的成矿系统问题[J].中国地质科学院院报,1983,第6号,1～64.
[10]程裕淇,赵一鸣,林文蔚.中国铁矿床[M].见宋叔和主编《中国矿床》中册.北京:地质出版社,1994,386～479.
[11]傅家谟.鄂西宁乡式铁矿的形成和分布规律[J].地质科学,1959,(4):109～115.
[12]傅家谟.鄂西宁乡式铁矿的相与成因[J].地质学报,1961,41(2):112～128.
[13]廖士范.中国南方宁乡式铁矿的岩相古地理条件及其成矿规律的探讨[J].地质学报,1964,44(1):68～80.
[14]云南地质局第四地质队.云南鱼子甸中泥盆世铁矿成矿地质特征[C].《铁铜矿产专辑》,第二集.北京:地质出版社,1974,38～52.
[15]湖南地质局414地质队.湘中地区宁乡式铁矿概况[C].《铁铜矿产专辑》,第三集.北京:地质出版社,1975,28～32.
[16]江西省地质局九○一大队.江西某地区宁乡式铁矿中菱铁矿的发现及其矿床地质特征[C].《铁铜矿产专辑》.北京:地质出版??976,115～122.
[17]姚培慧主编.中国铁矿志[M].北京:冶金工业出版社,1993,1～662.
[18]重庆市地质矿产勘探开发局川东南地质大队.重庆市巫山县桃花赤铁矿区详查2006年地质工作年报[R].2006,4～6.
[19]四川省地质矿产局.四川省区域地质志[M].北京:地质出版社,1991,580.
[20]贵州省地质矿产中心实验室.重庆市巫山桃花高磷鲕状赤铁矿物质组成研究报告[未刊].2007,8～11.
[21]李星学.中国晚古生代陆相地层[M].北京:科学出版社,1963,49～53.
[22]王钰,俞昌民.中国的泥盆系[M].北京:科学出版社,1962,32～37.
[23]杨式溥,胡昌铭,孙永传.汉阳锅顶山地区晚泥盆世遗迹化石的发现及其意义[J].地球科学,12(1):1～8.
[24]李星学,蔡重阳,欧阳舒.长江下游五通组研究的新进展[J].中国地质科学院院报,1984,第9号,119～136.
[25]曾允孚,张锦泉,刘文均,等.中国南方泥盆纪岩相古地理与成矿作用[M].北京:地质出版社,1993,1～123.
[26]姜在兴.沉积学[M].北京:石油出版社,2003,1～540.
[27]徐安武,胡宁,曾波夫.中扬子泥盆纪岩相古地理及有关矿产[C].岩相古地理文集(7).北京:地质出版社,1992,127～172.
[28]百度百科.石英砂的用途及作用[EB/OL].http://baike.baidu.com/view/35665.htm.
[29]刘宝珺.沉积岩石学[M].北京:地质出版社,1980,1～497.
[30]刘宝珺,许效松,潘杏南,等.中国南方古大陆沉积地壳演化与成矿[M].北京:科学出版社,1993,1～236.
[31]袁见齐,朱上庆,瞿裕生.矿床学[M].北京:地质出版社,1985,233～239.
[32]陈志明.沉积铁矿形成过程中的生物作用[J].1992,7(6):56～59.
[33]王守伦,刘其严,张殿学,等.闽粤地区海底热液喷气成因铁矿床的地球化学特征[J].1993,8(3):14～27.
[34]裴荣富.中国矿床模式:模式19、模式44[M].北京:地质出版社.1995,91～93,175～177.
[35] Gruner J.W..The Origin of Sedimentary Iron Formation[J].Econ.Geol.,1922,17(6): 407～460.
[36] L.Bubenicek.Geologie des minerais de fer oolithiques[J].Mineral.Deposita(Berl.),1968,3:89～108.
[37]刘英俊,曹励明.元素地球化学导论[M].北京:地质出版社,1987,128～133.
[38] Moore E.S.and Maynard J.E..Solution,Transportation and Precipitation of Iron and Silica[J].Econ.Geol.,1929,24(3、4、5):272～303、365～402、506～527.
[39]廖士范、魏梁鸿、刘成德,等.中国泥盆纪鲕铁石沉积环境、成因[J].沉积学报,1993,11(1):93～102.
[40]胡宁、徐安武.鄂西宁乡式铁矿分布层位岩相特征与成因探讨[J].地质找矿论丛,1998,13(1):40～47.
[41]陈志明.冀西北铁岩类型与沉积环境[J].地质科学,1981,16(4):338～343.
[42]赵东旭.宣龙铁矿铁质鲕粒的显微结构及成因[J].地质科学,1994,29(1):71～77.
[2]刘树臣,马建明,崔荣国.国内外铁矿资源供需形势[EB/OL].http://xian.gov.cn/kuangchanz iyuan/2008/0819/content_1556.html.
[3]赵一鸣,毕承思.宁乡式沉积铁矿床的时空分布和演化[J].矿床地质,2000,19(4):350～361.
[4]谢家荣,孙健初,程裕淇,等.扬子江下游铁矿志[Z].地质专报,1935,甲种第13号,1～78.
[5]丁格兰.中国铁矿志(1923,上下册)[Z].谢家荣译,地质专报甲种第二号,1938,27～276.
[6]王曰伦,刘祖彝,程裕淇.湖南宁乡铁矿地质[Z].地质汇报,1938,第32号,1～32.
[7]边效曾.铁矿的普查与勘探[M].北京:地质出版社,1958,1～189.
[8]程裕淇,赵一鸣,陆松年.中国几组主要铁矿类型[J].地质学报,1978,52(4):253～268.
[9]程裕淇,陈毓川,赵一鸣,等.再论矿床的成矿系统问题[J].中国地质科学院院报,1983,第6号,1～64.
[10]程裕淇,赵一鸣,林文蔚.中国铁矿床[M].见宋叔和主编《中国矿床》中册.北京:地质出版社,1994,386～479.
[11]傅家谟.鄂西宁乡式铁矿的形成和分布规律[J].地质科学,1959,(4):109～115.
[12]傅家谟.鄂西宁乡式铁矿的相与成因[J].地质学报,1961,41(2):112～128.
[13]廖士范.中国南方宁乡式铁矿的岩相古地理条件及其成矿规律的探讨[J].地质学报,1964,44(1):68～80.
[14]云南地质局第四地质队.云南鱼子甸中泥盆世铁矿成矿地质特征[C].《铁铜矿产专辑》,第二集.北京:地质出版社,1974,38～52.
[15]湖南地质局414地质队.湘中地区宁乡式铁矿概况[C].《铁铜矿产专辑》,第三集.北京:地质出版社,1975,28～32.
[16]江西省地质局九○一大队.江西某地区宁乡式铁矿中菱铁矿的发现及其矿床地质特征[C].《铁铜矿产专辑》.北京:地质出版??976,115～122.
[17]姚培慧主编.中国铁矿志[M].北京:冶金工业出版社,1993,1～662.
[18]重庆市地质矿产勘探开发局川东南地质大队.重庆市巫山县桃花赤铁矿区详查2006年地质工作年报[R].2006,4～6.
[19]四川省地质矿产局.四川省区域地质志[M].北京:地质出版社,1991,580.
[20]贵州省地质矿产中心实验室.重庆市巫山桃花高磷鲕状赤铁矿物质组成研究报告[未刊].2007,8～11.
[21]李星学.中国晚古生代陆相地层[M].北京:科学出版社,1963,49～53.
[22]王钰,俞昌民.中国的泥盆系[M].北京:科学出版社,1962,32～37.
[23]杨式溥,胡昌铭,孙永传.汉阳锅顶山地区晚泥盆世遗迹化石的发现及其意义[J].地球科学,12(1):1～8.
[24]李星学,蔡重阳,欧阳舒.长江下游五通组研究的新进展[J].中国地质科学院院报,1984,第9号,119～136.
[25]曾允孚,张锦泉,刘文均,等.中国南方泥盆纪岩相古地理与成矿作用[M].北京:地质出版社,1993,1～123.
[26]姜在兴.沉积学[M].北京:石油出版社,2003,1～540.
[27]徐安武,胡宁,曾波夫.中扬子泥盆纪岩相古地理及有关矿产[C].岩相古地理文集(7).北京:地质出版社,1992,127～172.
[28]百度百科.石英砂的用途及作用[EB/OL].http://baike.baidu.com/view/35665.htm.
[29]刘宝珺.沉积岩石学[M].北京:地质出版社,1980,1～497.
[30]刘宝珺,许效松,潘杏南,等.中国南方古大陆沉积地壳演化与成矿[M].北京:科学出版社,1993,1～236.
[31]袁见齐,朱上庆,瞿裕生.矿床学[M].北京:地质出版社,1985,233～239.
[32]陈志明.沉积铁矿形成过程中的生物作用[J].1992,7(6):56～59.
[33]王守伦,刘其严,张殿学,等.闽粤地区海底热液喷气成因铁矿床的地球化学特征[J].1993,8(3):14～27.
[34]裴荣富.中国矿床模式:模式19、模式44[M].北京:地质出版社.1995,91～93,175～177.
[35] Gruner J.W..The Origin of Sedimentary Iron Formation[J].Econ.Geol.,1922,17(6): 407～460.
[36] L.Bubenicek.Geologie des minerais de fer oolithiques[J].Mineral.Deposita(Berl.),1968,3:89～108.
[37]刘英俊,曹励明.元素地球化学导论[M].北京:地质出版社,1987,128～133.
[38] Moore E.S.and Maynard J.E..Solution,Transportation and Precipitation of Iron and Silica[J].Econ.Geol.,1929,24(3、4、5):272～303、365～402、506～527.
[39]廖士范、魏梁鸿、刘成德,等.中国泥盆纪鲕铁石沉积环境、成因[J].沉积学报,1993,11(1):93～102.
[40]胡宁、徐安武.鄂西宁乡式铁矿分布层位岩相特征与成因探讨[J].地质找矿论丛,1998,13(1):40～47.
[41]陈志明.冀西北铁岩类型与沉积环境[J].地质科学,1981,16(4):338～343.
[42]赵东旭.宣龙铁矿铁质鲕粒的显微结构及成因[J].地质科学,1994,29(1):71～77.