共查询到20条相似文献，搜索用时 93 毫秒
1.
国外锰矿资源、类型、地质特征及其对我国锰矿找矿的借鉴 总被引：1，自引：0，他引：1
本文所论述的内容限于陆地范围的锰矿床。世界锰矿资源达70亿吨,主要分布在南非、苏联,其次为澳大利亚、加蓬、巴西、印度、墨西哥和加纳等。世界重要锰矿床约150个,其超过1亿吨储量的有11处。本文据成矿作用、含锰建造、锰质来源及成矿条件等因素,将锰矿床分为5大类11个类型:海相沉积矿床(碎屑泥质岩型、碳酸盐岩型)、火山沉积矿床(绿岩硅质岩型、斑岩硅质岩型)、变质矿床(锰榴石英岩型或条带状含铁建造型)、热液矿床(接触交代型、裂隙充填型)和风化矿床(锰帽型、残积型、淋滤型),并综合其地质特征分列成表,各类型借以典型实例精要叙述。据世界锰矿资源、矿床类型、成矿时代,地质特征和控矿因素等特点,对我国锰矿找矿工作可引以为诫的是要注意前寒武纪(早元古代)变质锰矿床矿化信息的捕捉,要注意老第三纪(主要渐新世)地台型海相泥质岩型锰矿化线索的探寻,要重视火山沉积型锰矿的找矿,要继续加强表生风化型锰矿床的找矿和要注意铁、锰、铜和金矿的综合找矿。 相似文献
2.
一、地质简况锰矿点位于盐边某地一个背斜的北西翼。由奥陶系、志留系地层组成了向北倾斜的单斜构造。本文中所述的蔷薇辉石,则呈小透镜状、薄层状、产于中奥陶统巧家组(O_2~(?))碳酸盐岩地层内,与上下岩层呈整合接触。这套碳酸盐岩地层,受区域变质作用并不深,其中的燧石条带,泥质条带及生物碎屑等仍可见到。岩相古地理环境为古陆边缘的小型海湾,它接受了锰质及硅质等的沉积,这就为以后蔷薇辉石等的形成提供了 相似文献
3.
镁质碳酸盐岩型温石棉矿床是成矿热液交代镁质碳酸盐岩生成的,一般均产于地台环境。按地台稳定性不同,成矿环境分为地台隆起区的基底建造类型和地台拗陷区的盖层建造类型。产于地台隆起区的矿床,以前震旦纪镁质碳酸盐岩为控矿层位。产于太古代及早、中元古代深变质结晶基底中的矿床,由区域变质及混合岩化过程中的变质热液交代碳酸盐岩成矿。产于晚元古代浅变质褶皱基底(扬子准地台)中的矿床,以岩浆期后热液或接触交代(湿矽卡岩)热液为成矿热液来源。产于地台拗陷区的矿床,均以震旦纪镁质碳酸盐岩为控矿层位。其成矿时期较晚,一般与拗陷区内岩浆活动同期,由岩浆期后热液或接触交代(湿矽卡岩)热液对镁质碳酸盐岩进行交代成矿。 相似文献
4.
江绍断裂两侧早元古代变质基底特征及形成的构造环境 总被引：3，自引：0，他引：3
江绍断裂东侧出露的早元古代变质基底以一套遭受中压型角闪岩相区域热流变质作用改造的黑云斜长变粒岩、云母石英片岩为主，夹少量斜长角闪岩和大理岩，已遭受４期构造变形作用改造，从原岩建造和主要岩类地球化学特点推测它可能形成于大陆或大陆边缘类似于内硅铝盆地环境。江绍断裂西侧早元古代变质基底则以星子杂岩为代表，由变粒岩、浅粒岩、（十字一石榴）云母片岩和少量斜长角闪岩组成，已遭受中压型高绿片岩相一低角闪岩相区域热流变质作用改造，推测其形成于活动性较强大陆一大陆边缘环境。江绍断裂两侧早元古代变质基底在原岩建造、变质一变形作用等特征上存在明显差异，因此华夏地块和扬子地块在早元古代可能是两个地块。 相似文献
5.
滇西南澜沧群中氧化锰矿成矿规律及找矿前景 总被引：1，自引：0，他引：1
澜沧群中优质氧化富锰矿是层状，似层状硅酸锰矿层表生富集作用的结果，它的形成受到气候、地貌、水文条件及原生含锰建造特征的控制，南北向排列的元古代古火山口的火山化学沉积外圈，硅锰沉积建造因区域变质作用形成的原生硅酸锰矿分布区，具有寻找这类锰矿床的良好前景。 相似文献
6.
7.
8.
在辽东－吉南地区存在两个性质不同的变质地体：辽北地体和辽南地体,二者之间以断裂带或韧性剪切带相接。辽北地体包括北辽河群和老岭群,辽南地体包括南辽河群和集安群。不同变质地体内的早元古代变质岩系在地层系统及岩石组合、原岩建造及沉积环境、变质作用类型及ｐＴｔ轨迹、区域构造和岩浆活动等方面都存在明显的差别。它们在早元古代时期形成于不同的大陆边缘,具有完全不同的形成条件和演化历史。两个变质地体最晚在早元古代晚期经构造作用拼贴在一起。 相似文献
9.
辽东宽甸地区早元古代石榴黑云片麻岩是早期地壳演化的产物,其石榴石矿物成分环带记录了早期地壳演化史。早元古代地壳演化集中表现在区域变质作用上。该区石榴石(DFD9)成分环带记录着2期变质作用过程,其热力学条件的演化规律均表现在PTt 轨迹上。其中,早期区域变质作用发生在1900±Ma,与相应全球性构造-热事件密切相关,是一次峰期达到角闪岩相的变质作用。晚期变质作用发生在1600±Ma,是一次峰期达到高角闪岩相的变质作用。两期变质作用PTt 轨迹均显示顺时针的演化趋势,反映地壳沉降、抬升过程中的变质作用特点。 相似文献
10.
辽东地区古元古代裂谷里尔峪组和大石桥组中分别分布有富镁质的碳酸盐岩建造, 其中产有硼矿、菱镁矿、滑石、岫岩玉等大型-特大型矿床.这些镁质非金属矿床的形成先与古元古代的蒸发岩系有关, 然后经历了吕梁期区域变质和热液交代变质改造, 以及印支、燕山期构造-岩浆作用改造等成矿系统作用过程.其中, 镁质碳酸盐岩建造、成矿构造、成矿流体对镁质非金属矿床的形成起着重要的控制作用.这些矿床也是古元古代矿源场、流体场、热场(能量场)、应力场等在一定的时空条件下耦合和后期构造-岩浆作用叠加改造的综合产物. 相似文献
11.
中国锰矿成矿规律初探-陈毓川院士八十华诞专辑 总被引：3，自引：0，他引：3
中国锰矿资源较丰富,资源量排名在世界上位列第5.中国锰矿种类多样,有海相沉积型、火山-沉积型、碳酸盐岩中热水沉积型(或“层控”型)、与岩浆作用有关的热液型、受变质型及表生型.其中,海相沉积型占资源量的71.4％,表生型占15.7％,是最主要的两种类型.中国锰矿广泛分布于“泛扬子区”、华北陆块的燕辽地区以及天山和祁连山部分地区,尤以“泛扬子区”为最,并具分布广泛又相对集中的总体特征.中国的成锰时代多,中—新元古代、早古生代(寒武纪、奥陶纪)、晚古生代—早中生代是中国锰矿形成的重要时代.中国锰矿时-空分布的主要特征是“北锰南迁”:中元古代锰矿主要产于华北陆块的燕辽裂谷带,新元古代—古生代锰矿主要产于“泛扬子区”的大陆边缘盆地或台内盆地中.大型、超大型锰矿床或锰矿田的形成,受控于非构造期盆地性质、古海洋结构、古海水性质及海平面升降等因素,其形成环境存在一定的相似性及同源性. 相似文献
12.
锰的用途非常广泛,世界上90%~95%的锰应用于冶金工业,其余应用于电池工业、陶瓷工业、化学工业等。根据成矿作用过程中的含矿岩系特征,将世界锰矿划分为海相沉积型、火山(热液)-沉积型、变质型、热液型和表生型5类,以海相沉积型、变质型和表生型为主。截至2019年,世界锰的储量达8.12亿t,但分布极不均匀,主要集中在南非、巴西、乌克兰、澳大利亚、加蓬、中国、印度、加纳等国,而优质锰矿石主要分布在南非、澳大利亚、加蓬、加纳。时间上,将锰的成矿作用分为7期,其中元古宙和新生代是主要的成矿期。空间上,锰矿床主要分布在南非德兰士瓦群、乌克兰尼科波尔盆地、澳大利亚格鲁特岛和皮尔巴拉克拉通、中国泛扬子区、西非克拉通等。目前,锰的生产主要集中在南非的卡拉哈里和波斯特马斯堡锰矿田、澳大利亚的格鲁特岛、加蓬的莫安达锰矿、加纳的恩苏塔锰矿等地。 相似文献
13.
V. N. Kuleshov 《Lithology and Mineral Resources》2011,46(5):473-493
Major regularities in the formation of manganese rocks and ores have been established on the basis of available published
and original data. The proposed genetic classification of main manganese deposits (with model examples) is as follows: sedimentary-diagenetic
(Nikopol, Bol’she-Tokmak; Ukraine), (volcanogenic) hydrothermal-sedimentary (deposits of the Atasui area, Kazakhstan; Magnitogorsk
Trough, South Urals), epigenetic (catagenetic) (deposits of the Kalahari manganese ore field, South Africa; Usinsk deposit,
Kuznetsk Alatau), and supergene (residual, infiltrational, cavern filling, and pisolitic deposits in India, Brazil, South
Africa, and Australia). The results suggest the following conclusions: (1) all primary manganese rocks and ores at the known
deposits are hydrothermal- and diagenetic-sedimentary formations of marine environments; (2) manganese concentrations achieve
the size of deposits at postsedimentary stages of the initial manganiferous sediment and manganese rock transformation (diagenesis,
catagenesis, and retrograde diagenesis); (3) indispensable participation of the isotopically light carbon dioxide related
to the destruction of organic matter (OM) is a characteristic feature of manganese carbonate formation during diagenesis;
and (4) the role of organic carbon in manganese ore formation becomes notable since early stages of Mn accumulation in the
Precambrian sedimentary basins (terminal Archean-initial Early Proterozoic). 相似文献
14.
非洲锰矿床成矿规律、开发利用与勘查建议 总被引：1，自引：0，他引：1
锰矿是我国重要的战略矿产资源,需求量不断增长,长期依赖国外资源保障供需关系。本文总结分析了非洲锰矿资源的特点、矿床类型与成矿规律等地质特征与勘查开发利用及贸易现状。分析表明：非洲是全球探明锰矿储量和资源量最多的地区,具有分布集中,规模大、品位高、杂质少的特点;锰矿床类型主要有条带状含铁建造（BIF）型、海相沉积型、海相火山-沉积型、陆相（湖相三角洲）沉积型、岩浆热液型等五大类,普遍遭受表生风化淋滤（溶蚀）作用改造;主要分布在卡普瓦尔克拉通、刚果克拉通西北部的加蓬地块和西非克拉通南缘的马恩-莱奥地盾中;成矿时代主要集中于前寒武纪,尤其是2.2~2.0Ga;非洲锰矿资源的勘查开发程度较高,其中南非是非洲锰矿勘查程度最高的国家,中非、北非国家的勘查开发程度较低;南非是全球最大的锰矿石生产国和锰矿产品出口国,目前占全球出口量的68.19%以上,我国是非洲锰矿产的最大出口地,占其出口总量的70.19%。建议：我国在非洲的勘查应重点关注非洲中部的条带状含铁建造（BIF）型锰矿和海相火山-沉积型锰矿;在非洲已有的中企基础上,组建大型的集团公司,建立多元的锰矿资源供应体系。 相似文献
15.
It is shown that cooccurrences (parastereses) of chemical elements, minerals, sedimentary rocks, facies, and formations should be distinguished from their parageneses, which represent geological formations related to a single geological process. It has been established that phosphorus is concentrated in sedimentary manganese ores and is not accumulated in volcanosedimentary and hydrothermal deposits. Parageneses of Mn and P in sedimentary deposits are characterized. Parastereses of manganese ore and phosphorite-bearing facies in Oligocene rocks of southwestern Eurasia, Mesozoic and Upper Paleozoic sections of the Urals, and Mesozoic- Cenozoic sequences of Morocco are considered. 相似文献
16.
17.
18.
A Mesoarchean greenstone belt (3.5–3.0 Ga) in the western part of the East Indian Shield comprising the Iron Ore Group of the Noamundi basin contains economic resources of both iron and manganese ores in the NNE plunging regional synclinorium. Manganese mineralization in the central and eastern parts of this synclinorium, particularly in Joda–Noamundi sector, has taken place in multiple cycles starting from syngenetic sedimentary and exhalative type through mobilization and remobilization in different stages of tectonism, deformation and hydrothermal activities to latest lateritic or supergene type. A relatively high temperature metamorphic jacobsite–hausmannite–bixbyite–braunite assemblage, low temperature hydrothermal pyrolusite–psilomelane–hollandite assemblage and supergene pyrolusite–manganomelane–groutite–polianite assemblage are present and were formed by recycling of manganese in different stages of mineralization. A detailed structural study of the manganese ore bodies as well as their ore petrographic and mineralogical characteristics with mineral chemistry has revealed systematic mineralization and their relation to deformational phases. Such recycling of manganese and its structural control of mineralization in different phases is unique of its kind in comparison with other Archean manganese deposits in the world. 相似文献
19.
Datangpo-type sedimentary manganese deposits, which are located in northeastern Guizhou province and its adjacent areas, are Mn carbonate-type deposits hosted in black carbonaceous shale that represent a series of medium to large deposits containing a huge tonnage of reserves. PAAS-normalized rare earth element distribution patterns of manganese ores record “hat-shaped” REY (REE + Y) plots characterized by pronounced middle rare earth element enrichment, evident positive Ce anomalies, weak to strong positive Eu anomalies and negligible negative Y anomalies. These REY geochemical characteristics are different from those of country rocks and record the processes and features of sedimentation and diagenesis. Manganese was precipitated as Mn-oxyhydroxide particles in oxidized water columns with the sorption of a certain amount of rare earth elements, subsequently transforming from Mn-oxyhydroxides to rhodochrosite and redistributing REY in reducing alkaline pore-water during early diagenesis. A number of similarities can be observed through a comparison of Datangpo-type manganese ores and modern marine ferromanganese oxyhydroxide precipitates based on their rare earth elements. The precipitation of Datangpo-type manganese ores is similar to that of hydrogenetic crusts and nodules based on their positive Ce anomalies and relatively higher total REY concentrations. However, several differences also exist. Compared to hydrogenetic crusts and nodules, Datangpo-type manganese ores record smaller positive Ce anomalies, lower total REY concentrations, unobvious fractionation between Y and Ho, and weak to strong positive Eu anomalies. These were caused by quicker sedimentary rates in the oxic water columns of the shallower basin, after which pore water became strongly reducing and alkaline due to the degradation of organic matter in the early diagenetic stage. In addition, compared to typical deposits in the world, Datangpo-type manganese ores are similar to hydrogenetic deposits and different than hydrothermal deposits. All of these characteristics of manganese ores indicate that Datangpo-type manganese ores, the principal metallogenic factors of which include oxidation conditions during deposition and reducing conditions during early diagenetic stages, represent hydrogenetic deposits. 相似文献
20.
Vasconcelos P M 《中国地质大学学报(英文版)》2004,15(3):312-323
INTRODUCTIONModern4 0 Ar/ 39Arlaserstep heatinganalysishasbeensuccessfullyappliedtodateverysmallmineralgrainsfromdiversegeologicalenvironments .Thefineresolutionofthismethodhasgreatlyhelpovercomeproblemsintrinsicintradi tionalK Armethod ,inducedbyexcessargon ,argonlossbythermalresetting ,39Arrecoilduringirradiation ,andinter growthsand/orcontaminationofdifferentgenerationminer als ,withintheanalyzedmineral (Smithetal.,1998;Vas concelosetal.,1994 ) .Supergenemanganeseoredepositsareeconom… 相似文献