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1.
选取黔西北筲箕湾铅锌矿床作为研究对像,勘测其地质构造和矿体产出等特征,在显微镜下观察其矿石组构特征。利用红外显微镜对闪锌矿中的包裹体的类型、形态、盐度、均一温度进行了测量。分析结果表明,闪锌矿中的原生流体包裹体主要是富液相包裹体,气液比小,测得的均一温度范围为115.4~169.9℃,平均温度为140℃;冰点-0.5~-13.7℃,盐度0.88%~17.52%(eq.NaCl wt%),密度为0.92~1.06 g/cm3,流体的压力为1×105~5×105Pa。筲箕湾铅锌矿床成矿流体为浅成低温流体,盐度主要有低盐度流体和中等盐度两个端元,成矿机制可能是低盐度大气降水与携带矿质的中高盐度流体混和使铅锌产生沉淀形成。  相似文献   

2.
赤普铅锌矿床位于扬子地台西南缘川滇黔成矿区内,是川滇黔地区重要的铅锌矿床之一.通过野外和显微镜下观察,将成矿期形成的石英划分为Ⅰ、Ⅱ、Ⅲ三个阶段.本次选取了21件样品进行研究,对保存于石英、闪锌矿及硅化白云石中的原生包裹体进行的详细研究,赤普铅锌矿床中包裹体类型相对较为单一,以气液包裹体为主.Ⅰ、Ⅱ、Ⅲ阶段石英中流体包裹体均一温度和盐度范围分别为:230℃~270℃和2.74~19.68wt%(NaCl),150℃~200℃和3.71~16.99wt%(NaCI)和180℃~220℃和0.70~16.15wt%(NaCl)三个区间.主成矿阶段的闪锌矿流体包裹体的均一温度和盐度范围为127℃~210℃和4.34%~22.17%(NaCl).该矿床成矿流体均一温度和盐度范围主要在130℃~200℃和8.5%~17.0%(NaCl)之间,属于低温、中等盐度铅锌矿床.成矿流体为H2O-NaCl-CaCl2体系;成矿过程中成矿流体始终处于相对还原环境.成矿物质来源于上地壳,成矿流体主要来自围岩地层;成矿机制可能为含金属和舍还原硫流体混合成矿.该矿床应归属于密西西比型铅锌矿床.  相似文献   

3.
新疆西北部的托库孜巴依(巴依)金矿床位于西伯利亚古板块南缘,阿尔泰陆缘活动带克兰弧后盆地与哈巴河弧间盆地接壤处。本次研究在前人成果基础上,通过详细的野外调查、室内显微观察、流体包裹体测温、激光拉曼成分分析和氢-氧同位素分析等多种方法,揭示了巴依金矿各成矿阶段流体特征、成矿热液来源和流体演化过程。根据野外矿脉空间分布、穿插关系、矿物组合及结构构造等特征,结合流体包裹体研究,本文将巴依金矿的成矿作用划分为4个阶段:石英-磁铁矿阶段(Ⅰ),主要发育富液相包裹体,均一温度范围在3529~4134℃区间,盐度范围为73%~147%NaCleqv,平均为104%NaCleqv;石英-黄铁矿阶段(Ⅱ),该阶段主要发育富液相包裹体、富气相包裹体以及含子晶包裹体,均一温度范围为1860~3398℃,盐度变化范围为27%~443%NaCleqv,平均为92%NaCleqv;石英-黄铁矿-黄铜矿阶段(Ⅲ)主要发育富液相包裹体和含(富)CO_2三相水溶液包裹体,均一温度范围为1410~1864℃(富液相包裹体),盐度范围较大,介于0~88%NaCleqv之间;石英-方解石阶段(Ⅳ),流体包裹体以富液相为主,均一温度范围1020~1400℃,盐度范围为02%~43%NaCleqv。该矿床从成矿早阶段到成矿晚阶段温度-盐度整体呈下降趋势,在主要成矿阶段(Ⅱ、Ⅲ)出现流体沸腾现象。各成矿阶段δ~(18)O、δD同位素变化范围分别为:成矿早阶段(Ⅰ)531‰和-8510‰;主要成矿阶段(Ⅱ、Ⅲ)-153‰~150‰和-974‰~-811‰;成矿晚阶段(Ⅳ)-352‰~-342‰和-939‰~-871‰,成矿流体主要是早阶段的变质水与中晚阶段加入的大气水混合而成。巴依金矿成矿流体表现为一套中低盐度NaCl-H_2O-CO_2流体体系,符合造山型金矿成矿流体特征。综合矿床地质研究,本文认为在晚石炭世-二叠纪喀拉通克岛弧与西伯利亚板块碰撞造山构造体制下,流体混合、压力降低和沸腾作用是巴依金矿床富集成矿的主要机制。  相似文献   

4.
康家湾铅锌矿床位于湖南省水口山矿田,矿体主要产于二叠系当冲组下段泥灰岩、硅质岩与栖霞组灰岩的层间硅化破碎带中。根据矿物组合和穿插关系,可将该矿床的成矿作用过程划分为3个阶段:黄铁矿-石英阶段、闪锌矿-方铅矿(黄铁矿)-石英阶段和方解石-闪锌矿-方铅矿阶段。流体包裹体研究表明,康家湾铅锌矿床黄铁矿-石英阶段的流体主要为中-高温(243~343℃)、中-高盐度(18.4%~33.8% NaCleqv)的流体;闪锌矿-方铅矿(黄铁矿)-石英阶段的流体为中-高温(278~352℃)、中-低盐度(1.1%~20.7% NaCleqv)流体;晚期方解石-闪锌矿-方铅矿阶段的流体为低温(125~191℃)、低盐度(0.2%~6.7%NaCleqv)的流体。其中,闪锌矿-方铅矿(黄铁矿)-石英阶段的流体发生了沸腾作用。激光拉曼分析结果显示,该矿床成矿期的石英和闪锌矿中的液体包裹体气相成分主要为H_2O。H-O、S同位素研究显示,康家湾铅锌矿床的成矿流体可能主要来源于岩浆水,并在运移过程中混合了大气水。结合矿床地质、流体包裹体和氢氧、硫同位素特征,流体混合导致温度、盐度降低和沸腾作用可能是导致康家湾铅锌矿床成矿物质发生大规模沉淀的重要因素。  相似文献   

5.
新疆萨热阔布金矿床流体包裹体研究及矿床成因   总被引:2,自引:0,他引:2  
新疆萨热阔布金矿床位于阿尔泰造山带南缘克兰火山-沉积盆地内,矿体呈脉状产于康布铁堡组上亚组地层中(D1k2)。不同成矿阶段石英脉中广泛发育流体包裹体,可划分为H2O-CO2包裹体(C型)、纯CO2包裹体(PC型)、水溶液包裹体(W型)及含子矿物多相包裹体(S型)四类。测温结果显示,成矿早阶段主要发育C型和PC型包裹体,均一温度范围为271~446℃,流体盐度介于5.9%~8.4%NaCleqv之间;中阶段主要发育C、PC、W和S型包裹体,均一温度低于早阶段,为236~374℃,流体盐度介于4.8%~15.0%NaCleqv之间;晚阶段主要发育W型包裹体,均一温度范围为139~264℃,流体盐度介于1.1%~6.9%NaCleqv之间。对成矿压力和深度的估算表明,成矿压力为90~330MPa,成矿深度为9~12km。综上所述,萨热阔布金矿成矿流体具有富CO2、中低盐度的变质流体特征,流体沸腾导致了成矿物质的沉淀。结合矿床地质特征,萨热阔布金矿床属于造山型金矿床。  相似文献   

6.
哈尔达坂铅锌矿位于西天山赛里木湖铅锌成矿带.哈尔达坂铅锌矿床经历了 3期成矿作用:同生沉积期、成岩变质期、热液成矿期.同生沉积期石英中主要发育富液相包裹体,包裹体均一温度为143.8℃~208.4℃,盐度w(NaCl eq)为5.7%~8.0%.,成矿流体主要来源于海相碳酸盐岩;成岩变质期变质石英脉中主要发育富液相(L...  相似文献   

7.
江西香炉山矽卡岩型钨矿床流体包裹体研究   总被引:13,自引:5,他引:8  
从江西西北部至安徽南部发育一条显著的斑岩-矽卡岩型钨成矿带,香炉山是其中一典型的矽卡岩钨矿床。矿床具有明显的矿化分带特征,由近接触带矽卡岩和云英岩矿体和远接触带脉状石英-硫化物-白钨矿和透镜状矿体组成。通过对不同蚀变带上矿石矿物和脉石矿物的流体包裹体显微测温分析表明:矽卡岩中的流体包裹体的均一温度范围在209~383℃,脉状石英-白钨矿和石英-硫化物-白钨矿中流体包裹体的均一温度范围分别为163~278℃和204~284℃,晚期方解石脉的温度最低为143~235℃;矽卡岩中的流体包裹体的盐度范围在0.35%~5.26%NaCleqv,脉状石英-白钨矿和石英-硫化物-白钨矿中流体包裹体的盐度范围分别为0.35%~5.86%NaCleqv和0.70%~9.21%NaCleqv,晚期方解石脉的盐度为0.35%~2.07%NaCleqv。激光拉曼探针测试表明,矽卡岩、石英-白钨矿脉和石英-硫化物-白钨矿脉中流体包裹体组分主要为H2O,还含有一定量CH4和少量的N2。从早期到晚期成矿阶段表现为一个降温的过程,指明了钨成矿温度较宽泛;钨在流体中可能以钨酸的形式运移,与围岩反应时,温度降低和碱性升高,促使白钨矿沉淀成矿。早期到晚期成矿流体温度和物质组成发生变化是成矿发生分带的重要原因。  相似文献   

8.
迪彦钦阿木钼矿是近年来发现的一个超大型斑岩钼矿床,位于大兴安岭中段二连浩特-东乌旗多金属成矿带。本文主要对迪彦钦阿木钼矿床的流体包裹体及硫同位素进行了系统研究。迪彦钦阿木钼矿发育有四个成矿阶段:石英-钾长石阶段、石英-辉钼矿阶段、石英-多金属硫化物阶段及石英-萤石-碳酸盐阶段。矿床不同阶段的流体包裹体中,富气相(V类)、富液相(L类)和含子晶(S类)包裹体大量共存。显微测温结果显示,第一阶段包裹体均一温度为492~ 600℃,盐度分为两部分:5. 36%NaCleqv(L类)和32. 39%~64. 90%NaCleqv(S类);第二阶段包裹体均一温度为292~510℃,盐度为4. 49%~19. 92%NaCleqv(L类)和28. 43%~70. 21%NaCleqv (S类);第三阶段包裹体均一温度为206~388℃,盐度为2. 24%~22. 71%NaCleqv(L类)和28. 62%~54. 64%NaCleqv(S类);第四阶段包裹体均一温度、盐度最低,均一温度为133~288℃,盐度为0. 88%~7. 86%NaCleqv。流体具有从高温、高盐度向低温低盐度演化趋势。前三个成矿阶段L类、V类和S类包裹体大量共存,端元包裹体均一温度相近,盐度相差很大,表明发生了强烈的流体沸腾作用。多期次的流体沸腾作用是迪彦钦阿木矿床的主要成矿机制。硫同位素研究显示,δ~(34)S值的变化范围是1. 78‰~10. 41‰,暗示着迪彦钦阿木钼矿成矿物质主要来自于岩浆。  相似文献   

9.
阿奇山铅锌(铜)矿床是东天山觉罗塔格成矿带西段新发现的大型铅锌(铜)矿床,具有超大型矿床潜力。在分析矿床地质特征的基础上,对主成矿阶段的矿石矿物(闪锌矿、石英、方解石、石榴子石)进行流体包裹体测温和盐度测试。结果表明:包裹体以气液型两相为主,含子晶的三相包裹体少量,气液两相包裹体气液比为5%~10%,均一温度与盐度分别为94.8~440.1℃和4.8%~44.32%;其中闪锌矿明显分为高温闪锌矿(331℃)和低温闪锌矿(145~181℃),盐度主要分布在8%~14%和18%~22%。通过对流体包裹体的研究,结合矿床地质地球化学研究成果,显示阿奇山铅锌(铜)矿床主要存在早期硅酸岩热液和晚期碳酸盐热液2个成矿阶段,二者叠加部位为主成矿阶段,成矿流体具有低温、中盐度的特征,进而总结了矿床成矿模式。  相似文献   

10.
通过会泽矿山厂铅锌矿床闪锌矿流体包裹体显微测温和成矿物理化学条件参数计算,结合前人研究结果,得出以下认识:会泽矿山厂铅锌矿床闪锌矿流体包裹体均一温度为126280℃,具有较宽的变化区间,盐度(w(NaCl))为3.2%22.8%;白云石流体包裹体均一温度为86163℃,大部分盐度较低,为1.1%-14.8%。3个成矿阶段闪锌矿和白云石中流体包裹体均一温度和盐度具有较明显的分布特征:从热液成矿期Ⅰ阶段→Ⅱ阶段→Ⅲ阶段→围岩蚀变,流体呈现中高温-高盐度→中温-中高盐度→中低温-中高盐度→中低温-低盐度的演化规律。在整个热液成矿过程中,有两种不同盐度的流体参与了作用,流体混合可能是矿物沉淀的主要机制。pH值计算结果表明,迁移阶段时,成矿流体呈酸性,从成矿阶段Ⅰ—Ⅳ,流体pH逐渐增大,主成矿阶段Ⅱ—Ⅲ时,闪锌矿和方铅矿在中性、弱碱性下大量析出。受控于CO、CO_2、O_2间逸度平衡的CO_3~(2-)和HCO_3~-缓冲对调节了成矿流体的pH值,碳酸盐岩在铅锌的运移沉淀中起了至关重要的作用。  相似文献   

11.
Numerical and analytical models of fluid flow that account for fluid production during prograde regional and contact metamorphism show that expulsion of metamorphic fluids dominates the convective flux when crustal permeabilities are less than 0.1–100 μD, depending primarily on the rate of fluid production. When this is the case, fluid circulation is limited or prevented, fluid pressures are elevated above hydrostatic values, and flow throughout most of the model is up and away from the region of maximum fluid production. Fluid circulation is predicted to occur where permeability is high, in dry rocks, or after rates of fluid production decrease as peak temperatures are reached. Large changes in the pattern of flow and influx of externally derived fluids may thus occur in metamorphic terranes when dehydration wanes or ceases and cooling begins. Inclusion of an impermeable horizon in the models further inhibits fluid circulation. Earlier, shallow hydrothermal models and interpretations based on the Rayleigh number may be inappropriate for characterizing fluid flow during prograde metamorphism at depth because they do not account for fluid production.  相似文献   

12.
含油气盆地中热流体活动的流体包裹体依据   总被引:1,自引:0,他引:1  
彭晓蕾  高玉巧  刘立 《世界地质》2005,24(4):350-355,377
为寻找含油气盆地中热流体活动的证据,根据国内外含油气盆地中与热流体有关的包裹体的对比研究,阐述了流体包裹体宿主矿物产状、形貌特点及均一温度实测值高异常等特征。研究表明,脉体矿物多数是与热流体活动有关的包裹体的宿主矿物,有些碎屑矿物成岩愈合微裂隙中的包裹体也与热流体活动有关。沸腾包襄体反映了油气成藏与热流体的脉动式活动密切相关。流体包裹体的均一温度高异常是由热流体活动所导致的。因此,流体包裹体研究对识别古热流活动具有重要的指示意义。  相似文献   

13.
贵州太平洞金矿床流体包裹体特征及流体不混溶机制   总被引:7,自引:2,他引:5  
太平洞金矿床是兴仁-安龙金矿带灰家堡金矿区的重要卡林型金矿之一。流体包裹体研究证明,石英-黄铁矿阶段(Ⅰ)、石英-黄铁矿-毒砂阶段(Ⅱ)、石英-方解石-雄黄阶段(Ⅲ)的包裹体类型丰富,以气液水两相包裹体、CO2-H2O包裹体和纯液相水包裹体为主,CO2两相包裹体、纯气相有机质包裹体和有机质-H2O包裹体次之,偶见气液有机质包裹体。由Ⅰ→Ⅱ→Ⅲ阶段,气液水包裹体均一温度(200~260℃→180~240℃→100~160℃)呈现逐渐降低的趋势。在Ⅰ阶段的石英中,只在局部偶见到CO2-H2O包裹体和气液两相水包裹体共生;在Ⅱ阶段的石英中,纯液相水包裹体、气液两相盐水包裹体、CO2-H2O包裹体、CO2包裹体及纯气相有机质包裹体共存,它们共生在同一平面中且气液两相盐水包裹体和CO2-H2O包裹体测温数据相差不大,说明当时捕获的是不均匀成矿流体,它是由含有机质的成矿流体经历了CO2-低盐度水的不混溶作用形成的。因而认为,太平洞金矿床中成矿早期流体不混溶作用不明显,主成矿阶段流体的不混溶作用是导致金矿质沉淀的重要原因。  相似文献   

14.
高庄金矿床形成于华北板块和扬子板块造山后的板内伸展环境,矿体是二郎坪群中充填于平行造山带走向的脆韧性剪切带中的石英-金多金属硫化物矿脉。本次运用"流体包裹体组合"(FIA)方法进行流体包裹体特征研究。研究表明,高庄金矿含矿石英中包裹体主要有CO_2-H_2O型三相包裹体、CO_2包裹体和水溶液包裹体3种类型,其中,CO_2-H_2O型三相包裹体为主体类型,完全均一温度变化范围为286~349℃,w(Na Cleq)为0.41%~4.14%,估算流体密度为0.788~0.874 g/cm3,成矿压力为130~160 MPa,成矿深度为4.8~5.9 km,成矿流体具有中温,富CO_2、低盐度的特征。在同一视域内可见CO2-H2O型三相包裹体和水溶液包裹体共存,均一方式各异,且均有相近的均一温度,指示存在流体不混溶作用。成矿流体中水的δDH_2O=-83.4‰~-76.3‰,δ18OH_2O=5.8‰~7.1‰,显示成矿流体来自于岩浆热液。结合区域构造背景,认为高庄金矿床为形成于华北板块与扬子板块碰撞造山作用后,板块内部构造变形过程中形成的中温岩浆热液型金矿。  相似文献   

15.
流体不混溶性和流体包裹体   总被引:16,自引:4,他引:12  
卢焕章 《岩石学报》2011,27(5):1253-1261
大多数流体包裹体是捕获于均匀体系,但有一部分包裹体捕获自非均匀体系(不混溶体系)。在自然界存在着许多不混溶的过程,这包括基性岩浆和酸性岩浆之间,岩浆与热液,岩浆与CO2,盐水溶液与CO2等。液体的不混溶性对于成矿作用十分重要,这方面有3个典型的例子,第一个是金矿的成矿作用与NaCl-H2O-CO2体系流体的不混溶有着重大的关系;第二个例子是斑岩铜矿;第三个例子是伟晶岩,发现在伟晶岩演化和成矿作用中存在着岩浆和热液的不混溶作用。实际上不混溶的大部分证据是从流体包裹体的研究中获得的。现在的问题是如何来确定哪些包裹体是从不混溶过程中捕获的。这种捕获于不混溶过程中的流体包裹体怎么来确定他的Th和成分。这种捕获于不混溶过程中的流体包裹体怎么与"卡脖子"拉伸作用"中捕获的包裹体和捕获自均匀体系的流体包裹体相区分。  相似文献   

16.
We have investigated the geochemical pattern of fluid infiltration in the extensional detachment of Tinos Island (Cyclades, Greece). Ion microprobe O-isotope analyses and fluid inclusion studies have been conducted in strain fringes developing around pyrite blasts in the mylonite of the shear zone. Micro-scale traverses in quartz and calcite fibres show that δ18O increases from 17–18 to 20–21‰ in 1 mm towards the blast, drops of 3‰ in ∼200 μm, then rises again in the direction of growth. δ18O variations are interpreted as transient influxes of exotic fluids into the shear zone between periods of closed system buffering by the host rock. Fluid inclusions trapped in the fibres show fluctuating salinities (0–4 wt% NaCl eq.) and densities that reflect drops of the pore pressure from lithostatic (λ=1) to hydrostatic (λ=0.4) values during fringe growth. Isotopic and microthermometric data are consistent with models of seismic pumping developed for compressive shear zones. We therefore suggest that co-seismic pore pressure variations developed suction forces sufficient to drive large-scale fluid migration in the Tinos detachment, as in convergent tectonic settings.  相似文献   

17.
The Bismark deposit (8.5 Mt at 8% Zn, 0.5% Pb, 0.2% Cu, and 50 g/t Ag) located in northern Mexico is an example of a stock-contact skarn end member of a continuum of deposit types collectively called high-temperature, carbonate-replacement deposits. The deposit is hosted by massive sulfide within altered limestone adjacent to the Bismark quartz monzonite stock (~42 Ma) and the Bismark fault. Alteration concurrently developed in both the intrusion and limestone. The former contains early potassic alteration comprising K-feldspar and biotite, which was overprinted by kaolinite-rich veins and alteration and later quartz, sericite, and pyrite with minor sphalerite and chalcopyrite. Prograde exoskarn alteration in the limestone consists of green andradite and diopside, and transitional skarn comprising red-brown andradite, green hedenbergite and minor vesuvinite, calcite, fluorite, and quartz. The main ore stage post-dates calc-silicate minerals and comprises sphalerite and galena with gangue pyrite, pyrrhotite, calcite, fluorite, and quartz. The entire hydrothermal system developed synchronously with faulting. Fluid inclusion studies reveal several distinct temporal, compositional, and thermal populations in pre-, syn- and post-ore quartz, fluorite, and calcite. The earliest primary fluid inclusions are coexisting vapor-rich (type 2A) and halite-bearing (type 3A; type 3B contain sylvite) brine inclusions (32 to >60 total wt% salts) that occur in pre-ore fluorite. Trapping temperatures are estimated to have been in excess of 400 °C under lithostatic pressures of ~450 bar (~1.5 km depth). Primary fluid inclusions trapped in syn-ore quartz display critical to near critical behavior (type 1C), have moderate salinity (8.4 to 10.9 wt% NaCl equiv.) and homogenization temperatures (Th) ranging from 351 to 438 °C. Liquid-rich type 1A and 1B (calcite-bearing) inclusions occur as primary to secondary inclusions predominantly in fluorite and show a range in Th (104–336 °C) and salinity (2.7–11.8 wt% NaCl equiv.), which at the higher Th and salinity ranges overlap with type 1C inclusions. Oxygen isotope analysis was carried out on garnet, quartz, and calcite (plus carbon isotopes) in pre-, syn-, post-ore, and peripheral veins. Pre-ore skarn related garnets have a δ18Omineral range between 3.9 and 8.4‰. Quartz from the main ore stage range between 13.6 and 16.0‰. Calcite from the main ore stage has δ13C values of –2.9 to –5.1‰ and δ18O values of 12.3 to 14.1‰, which are clearly distinct from post-ore veins and peripheral prospects that have much higher δ18O (16.6–27.3‰) and δ13C (1.3–3.1‰) values. Despite the numerous fluid inclusion types, only two fluid sources can be inferred, namely a magmatic fluid and an external fluid that equilibrated with limestone. Furthermore, isotopic data does not indicate any significant mixing between the two fluids, although fluid inclusion data may be interpreted otherwise. Thus, the various fluid types were likely to have formed from varying pressure–temperature conditions through faulting during exsolution of magmatic fluids. Late-stage hydrothermal fluid activity was dominated by the non-magmatic fluids and was post-ore.  相似文献   

18.
A mantle plume formation model based on possible migration of fluid in the plastic mantle as subvertical isolated cavities-fractures is offered. Excessive pressure (EP) proportional to the vertical size of the cavity and the difference in fluid and rock densities appears in such cavities under plasticity conditions. The excess of the EP value over rock hardness results in ??fluid fracturing?? (by analogy with hydrofracturing) in the ??head?? and, due to the cavity volume stability, in collapse of the fracture tail providing its movement upwards. Gas emission from the Earth??s core is accompanied by its accumulation at the boundary between the core and the mantle as fluid lenses, which having attained a critical size break through the mantle and migrate to the surface. In fact, a relatively stable fluid flow is created in the mantle heating it up and interacting with it. The flow stops down in the hard lithosphere base and spreads laterally initiating mantle metamorphism and melting accompanied by the formation of magmatic reservoirs massively intruding and flowing out when the critical height is attained.  相似文献   

19.
PAA无固相冲洗液的研究与应用   总被引:3,自引:0,他引:3  
为解决松软岩层钻孔施工中的护壁问题,经反复实验研制开发的PAA无固相冲洗液粘度可在18~30s范围内调整,以适应不同地层要求。该冲洗液的护壁作用主要是高分子链中的官能团在助剂A和助剂B的双重交联下,形成致密、坚韧、柔性好的网,吸附或渗入岩石缝隙间,起到网络、胶结破碎层的作用。经在狮子庙矿区试验,钻探直接成本降低了74 6%,钻孔事故率由52%下降到0 2%,台·月进尺、台·月效率提高3倍,优质孔率达到100%。  相似文献   

20.
安鹏  陈懋弘  孔志岗  陈港  王昱 《矿床地质》2023,42(5):907-926
广西隆或金矿床位于右江盆地隆或孤立碳酸盐岩台地内部,为一产于C/D不整合面上的层状卡林型矿床。为了查明隆或金矿的成矿流体来源,探讨矿床成因,本次工作对其开展了详细的野外地质考察,对不同成矿阶段石英、方解石进行了系统的包裹体岩相学观察、显微测温及C-H-O-He-Ar同位素分析。包裹体岩相学及测温结果显示,石英、方解石中主要发育富液相气液两相水溶液包裹体,含有少量CO2三相包裹体。其中石英中包裹体均一温度集中在170.4~282.6℃,盐度w (NaCleq)集中在2.57%~8.41%,密度为0.774~0.938 g/cm3;方解石中包裹体的均一温度集中在178.5~237℃,盐度w (NaCleq)集中在2.9%~7.17%,密度为0.845~0.935 g/cm3,为中低温、低盐度、低密度的H2O-NaCl体系。通过计算得出成矿流体的成矿压力为45.83~74.17 MPa,成矿深度为1.611~2.472 km。石英的δ18OV-SMOW值为25.5‰~28.7‰,对应的δ18OH2O为14.10‰~17.18‰,δDV-SMOW值为-79‰~-51‰,两个阶段石英H、O同位素投点虽位于变质水区域及附近,但Ⅱ阶段石英具有向岩浆水漂移的趋势。方解石的δ13CPDB集中在-6.5‰~-4.6‰,δ18OV-SMOW分布在19.9‰~21.1‰,其投点靠近海相碳酸盐岩区域,表明方解石的形成主要来源于碳酸盐的溶解。石英包裹体中3He/4He的值为0.351~0.744 Ra,位于地幔氦和地壳氦之间,幔源He (%)值为5.11%~11.17%,说明地壳流体占主导地位;方解石中3He/4He值为0.038~0.073 Ra,位于地壳氦附近。石英、方解石的40Ar/36Ar值为303.1~436.4,经计算得成矿流体中大气40Ar贡献介于67.71%~97.49%,表明了成矿流体具有壳幔混合的特征,并且有大量大气水的参与。综上分析,文章推测隆或金矿床中原始成矿流体来自深部岩浆流体,原始成矿流体在上升过程中与盆地建造水发生混合,形成了多流体混合的成矿流体,并且随着成矿的进行,大量的大气降水或地下水的渗入。结合构造环境、矿化蚀变等特征,文章认为隆或金矿床为中低温低压浅成热液卡林型金矿床。  相似文献   

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