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1.
Stable isotopic and fluid inclusion evidence for meteoric fluid penetration into an active mountain belt; Alpine Schist, New Zealand 总被引：2，自引：0，他引：2
Calcite and quartz veins have formed, and are forming, in steeply dipping fissures in the actively rising Alpine Schist metamorphic belt of New Zealand. The fluids that deposited these minerals were mostly under hydrostatic pressure almost down to the brittle-ductile transition, which has been raised to 5-6 km depth by rapid uplift. Some fluids were trapped under lithostatic pressures. Fluids in the fissure veins were immiscible H2 O + NaCl-CO2 mixtures at 200-350 C. Bulk fluid composition is 15-20 mol% CO2 and <4.3 total mol CH4 + N2 + Ar/100mol H2 O. Water hydrogen isotopic ratio δDH2 O in the fissure veins spans -29 to -68‰, δ18 OH2 O -0.7 to 8.5‰, and bulk carbon isotopic ratio δ13 C ranges from -3.7 to -11.7‰. The oxygen and hydrogen isotopic data suggest that the water has a predominantly meteoric source, and has undergone an oxygen isotope shift as a result of interaction with the host metamorphic rock. Similar fluids were present during cooling and uplift. Dissolved carbon is not wholly derived from residual metamorphic fluids; part may be generated by oxidation of graphite. 相似文献
2.
Abstract Andalusite-bearing veins formed during contact metamorphism in the aureole of the Vedrette di Ries tonalite. In the veins, quartz crystals that are completely armoured by andalusite or that occur in strain shadow areas contain three generations of fluid inclusions: low-salinity H2 O-CO2 -CH4 mixtures with CH4 /(CO2 + CH4 ) ± 0.35 (type A); low-salinity aqueous fluids (type B); H2 O-free, CO2 -CH4 fluids with the same carbonic speciation as A (type C). Carbonic types A and C typically have a dark appearance, which is attributed to graphite coatings on inclusion walls. Microstructural analysis of the host quartz and calculated densities indicate that type A inclusions were likely trapped during vein formation. These inclusions underwent strain-assisted re-equilibration during cooling that resulted in density increases without change of composition. After the rocks had cooled below about 350 ° C, type C inclusions appear to have formed from one of the immiscible fractions after unmixing of the H2 O-CO2 -CH4 fluid mixtures. Aqueous type B inclusions, apparently trapped between 225 and 350 ° C, could represent an independent fluid, or could be the H2 O-rich fraction of unmixed type A fluids. Taking account of the uncertainties, the composition and density of the complex type A inclusion fluids are in good agreement with the properties of primary fluids calculated from the petrological data. The fluid inclusion data support the model of vein formation by hydrofracturing as a result of dehydration of graphitic metapelites. These new results also demonstrate the importance of considering strain in the interpretation of metamorphic fluid inclusions. 相似文献
3.
Results of electron microprobe and microthermometric studies of samples collected from the Bouvet Triple Junction Region (BTJR) during a joint Russian-Italian geological expedition on the R/V Academician Nikolaj Strakhov (1994) have revealed new data on the composition of basaltic magmas and oceanic hydrothermal fluids connected with magmatic processes. Detailed analysis of basaltic glasses shows that the modem Mid-Atlantic Ridge (MAR) rift valley is composed of normal mid-ocean ridge basalts with low concentrations of K2 O and TiOz (N-MORB), while its flanks are more enriched with these components approaching E-MORB. A marked influence of the Bouvet hot spot volcanism on magma generation on the South-West Indian Ridge (SWIR) near Bouvet Island is observed. Basaltic melts in this area belong to alkalic and transitional series and have maximum contents of K2 O, TiO2 , H2 O.
Microthermometric analyses of fluid inclusions in the samples from the BTJR have revealed major differences in the oceanic hydrothermal fluid systems on the MAR and near SWIR, which depends on the peculiarities of magma. In the area of the MAR (with dry melts) only H2 O solution inclusions in quartz were found; thus, seawater is probably the only primary source of hydrothermal fluids (NaCl + MgCl2 + H2 O; T = 170–200°C). In the SWIR area (with the high content of water in melts) syngenetic liquid CO2 and H2 O solution inclusions in quartz indicate the influence of the magmatic fluid component on the ore-forming water/carbon dioxide solutions (NaCl + CaC12 + H2 O + CO2 ; T = 200–310 °C; P = 900–1700 bar). 相似文献
Microthermometric analyses of fluid inclusions in the samples from the BTJR have revealed major differences in the oceanic hydrothermal fluid systems on the MAR and near SWIR, which depends on the peculiarities of magma. In the area of the MAR (with dry melts) only H
4.
Submillimeter Scale Variation of Oxygen Isotope of Vein Quartz at the Hishikari Deposit, Japan 总被引：2，自引：1，他引：1
Abstract: The physical and chemical mechanism of gold precipitation in the typical low-sulfidation epithermal gold deposit at the Hishikari mine was quantified by submillimeter scale oxygen isotope analyses of vein quartz. In situ CO2 laser-ablated fluorination was used to measure temporal δ18 O excursions. The calculated oxygen isotopic compositions of the ore-forming fluid indicate a dynamic process of epithermal vein formation. Intermittent opening of the vein allowed introduction of metal-bearing deep fluid to the epithermal system, and associated boiling and subsequent mixing with meteoric water caused precipitation of precious metals. 相似文献
5.
L.S. HOLLISTER 《Journal of Metamorphic Geology》1988,6(4):467-474
Abstract Nearly pure CO2 fluid inclusions are abundant in migmatites although H2 O-rich fluids are predicted from the phase equilibria. Processes which may play a role in this observation include (1) the effects of decompression on melt, (2) generation of a CO2 -bearing volatile phase by the reaction graphite + quartz + biotite + plagioclase = melt + orthopyroxene + CO2 -rich vapour, (3) selective leakage of H2 O from CO2 + H2 O inclusions when the pressure in the inclusion exceeds the confining pressure during decompression, and (4) enrichment of grain-boundary vapour in CO2 by subsolidus retrograde hydration reactions. 相似文献
6.
Abstract. The Onsen site is an active submarine hydrothermal system hosted by the Desmos caldera in the Eastern Manus Basin, Papua New Guinea. The hydrothermal fluid is very acidic (pH=1.5) and abundant native sulfur is deposited around the vent. The δ34 S values of native sulfur range from -6.5 to -9.3 %o. δ34 S values of H2 S and SO4 in the hydrothermal fluid are -4.3 to -9.9 %o and +18.6 to +20.0 %o, respectively. These δ34 S values are significantly lower than those of the other hydrothermal systems so far reported. These low δ34 S values and the acidic nature of the vent fluids suggest that volcanic SO2 gas plays an important role on the sulfur isotope systematic of the Onsen hydrothermal system. Relationship among the δ34 S values of S-bearing species can be successively explained by the model based on the disproportionation reaction starting from the volcanic SO2 gas. The predicted δ34 S values of SO2 agree with the measured whole rock δ34 S values. δD and δ18 O values of clay minerals separated from the altered rock samples also suggest the contribution of the magmatic fluid to the hydrothermal system. Present stable isotopic study strongly suggests that the Onsen hydrothermal site in the Desmos caldera is a magmatic submarine hydrothermal system. 相似文献
7.
Makoto Haruna Takahiro Hanamuro Kaoru Uyeda Hirokazu Fujimaki Hiroshi Ohmoto 《Resource Geology》2003,53(2):75-88
Abstract. The petrography, chemical, fluid inclusion and isotope analyses (O, Rb-Sr) were conducted for the shale samples of the Mount McRae Shale collected from the Tom Price, Newman, and Paraburdoo mines in the Hamersley Basin, Western Australia. The Mount McRae Shale at these mines occurs as a footwall unit of the secondary, hematite-rich iron ores derived from the Brockman Iron Formation, one of the largest banded iron formations (BIFs) in the world. Unusually low contents of Na, Ca, and Sr in the shales suggest that these elements were leached away from the shale after deposition. The δ18 O (SMOW) values fall in the range of + 15.0 to +17.9 per mil and show the positive correlation with calculated quartz/sericite ratios of the shale samples. This suggests that the oxygen isotopic compositions of shale samples were homogenized and equilibrated by postdepositional event. The pyrite nodules hosted by shales are often rimmed by thin layers of silica of varying crystallinity. Fluid inclusions in quartz crystals rimming a pyrite nodule show homogenization temperatures ranging from 100 to 240C for 47 inclusions and salinities ranging from 0.4 to 12.3 wt% NaCl equivalent for 18 inclusions. These fluid inclusion data give direct evidence for the hydrothermal activity and are comparable to those of the vein quartz collected from the BIF-derived secondary iron ores (Taylor et al, 2001). The Rb-Sr age for the Mount McRae Shale is 1,952 ± 289 Ma and at least 200 million years younger than the depositional age of the Brockman Iron Formation of ∼ 2.5 Ga in age. All the data obtained in this study are consistent with the suggestion that high temperature hydrothermal fluids were responsible for both the secondary iron ore formation and the alteration of the Mount McRae Shale. 相似文献
8.
9.
乌日尼图钨钼矿位于内蒙古苏尼特左旗境内,是近几年该区新发现的较大规模的钨钼矿床.钨钼矿体主要产于燕山期花岗岩体的内外接触带附近,以细脉状矿化类型为主.该矿床中的流体包裹体主要发育气液两相、富气相、富液相和纯液相包裹体等类型.包裹体均一温度为130.0~371.7 ℃(峰值为160.0~260.0 ℃),盐度为0.2%~15.9% NaCl eqv(峰值为0.2%~12.5% NaCl eqv),属于中低温、中低盐度钨钼矿床.激光拉曼和群体包裹体成分分析结果表明,流体体系气相成分以H2O、CO2为主,其次为N2、O2以及少量CO、CH4、C2H2、C2H4和C2H6等; 液相成分以Ca2+、Na+、SO42-、Cl-为主,其次为K+、F-、NO3-、Mg2+以及少量Br-和Li+.成矿流体为H2O-NaCl-CO2体系.流体包裹体氢氧同位素分析表明,成矿流体的δ18O水的含量范围为-2.11%~-0.11%,δD水的含量范围为-85%~-108%,成矿流体为岩浆水与大气降水的混合物.结合矿床地质和成矿流体特征,认为该矿床为与燕山期岩浆活动有关的中低温热液石英脉型钨钼矿床,成矿物质以深源为主. 相似文献
10.
Abstract: Fluid inclusions in hydrothermal quartz and anhydrite samples from the Mori geothermal field, southwest Hokkaido, have been studied microthermometrically using heating/freezing stages. Based on homogenization temperatures of fluid inclusions, salinities after correction of effect of freezing-point depression of CO2 on ice melting temperatures of fluid inclusions, and previous geochemical data by Yoshida (1991), we discuss the geneses of various types of inclusion fluids in the Mori geothermal reservoir. 相似文献
11.
A breccia vein sampled from a shear zone in greenschist facies metapelites at Mount Isa, Queensland, Australia, shows a systematic variation in vein geometry that is related to the geometry of folding and faulting within the sample. Calcite vein-fill is coarse grained and equigranular, suggesting precipitation in a fluid-filled space. Partially folded veins suggest that veining occurred during folding and faulting. The breccia vein contains a central zone in which dilation has occurred simultaneously in all directions in the plane of section, implying that this was a zone of high fluid pressure and nearly isostatic differential stress during folding and faulting. From these observations, it can be inferred that the breccia vein was a zone of high permeability and a likely fluid channel during deformation. This hypothesis was tested by stable isotope analysis of veins and host rocks. The calcite veins have δ13 C values of -11.1 ± 0.1% and δ18 O values of 6-10%o , whereas the host metapelite has δ13 C values of -10.62 and -10.11% and δ18 O values of 14-15%o . These values are consistent with an igneous-derived, H2 O-dominated fluid that exchanged little oxygen with the host rocks, but derived much of its carbon from the wall rock. The isotopic disequilibrium between the veins and the wall rock confirms that the fluid was externally derived, and that the breccia vein acted as a channel for large-volume fluid flow within the shear zone. 相似文献
12.
A sequence of regional metamorphic isograds indicating a range from prehnite-pumpellyite to lower amphibolite facies was mapped in metabasites near Flin Flon, Manitoba. The lowest grade rocks contain prehnite + pumpellyite and are cut by younger brittle faults containing epidote + chlorite + calcite. Isobaric temperature- X CO2 and pressure-temperature (constant X CO2 ) diagrams were calculated to quantify the effects of CO2 in the metamorphic fluid on the stability of prehnite-pumpellyite facies minerals in metabasites containing excess quartz and chlorite. Prehnite and, to a lesser extent, pumpellyite are stable only in fluids with X co2 <0.002. For X co2 >0.002, epidote + chlorite + calcite assemblages are stable. Our calculated phase relations are consistent with regional metamorphism in the Flin Flon area in the presence of an H2 O-rich fluid and a more CO2 -rich fluid in the later fault zones. We believe that the potential effects of small amounts of CO2 in the metamorphic fluid should be assessed when considering the pressure-temperature implications of mineral assemblages in low-grade metabasites. 相似文献
13.
良山钼矿是近年来赣中地区新发现的钼矿,浅部矿体主要赋存于南华系浅变质岩系的构造裂隙中,矿石类型以含辉钼矿石英脉为主。流体包裹体岩相学和显微测温结果表明：含辉钼矿石英脉中的流体包裹体主要呈星散状随机或成群分布,其形态多样,大小集中在2~15 μm,包裹体的类型主要有纯液相包裹体、富气相两相包裹体、富液相两相包裹体和含液体CO2三相包裹体4类,其中以富液相两相包裹体最为发育;包裹体的均一温度为136~298 ℃,盐度为1.22%~10.11%NaCleqv,密度为0.78~0.99 g/cm3,成矿流体属中-低温、低盐度、较低密度流体;成矿压力估算为13~70 MPa,形成深度为0.5~2.6 km。流体包裹体激光拉曼光谱分析表明：包裹体中气液相成分以H2O为主,气相中还有少量的CO2和CO。H、O、S同位素组成显示：成矿流体的δD值介于-61‰~-57.9‰,δ18OH2O值介于-3.32‰~-0.52‰,具有岩浆水和大气降水混合的特征;成矿热液中的δ34S值介于-1.8‰~+1.9‰,具有岩浆硫的特征。综合成矿地质特征及相关分析,认为成矿流体可能与燕山期的岩浆活动有关,属于岩浆热液流体,混合作用及钾化作用是促进金属富集沉淀成矿的主要因素,推测矿床属于岩浆热液充填石英脉型钼矿。 相似文献
14.
Abstract Oxygen and hydrogen isotope analyses have been made of coexisting quartz, ilmenite, muscovite, and biotite from Late Precambrian metapelitic rocks, staurolite-kyanite to K-feldspar-muscovite-sillimanite zones, from Mica Creek, British Columbia. The δ18 O and †D values of these minerals are generally uniform and do not decrease significantly with increasing metamorphic grade. This implies that there has not been significant infiltration of deep crustal, possibly magmatic, fluids into the metapelites that has been suggested for other high-grade metamorphic terranes. The uniformity of oxygen isotope compositions of the Mica Creek metapelite rocks may reflect isotopic uniformity in the sedimentary protolith rather than widespread exchange with an isotopically homogeneous metamorphic pore fluid.
Temperature estimates based upon18 O exchange thermometry for samples below the sillimanite zone are in reasonable agreement with the results of garnet-biotite Fe–Mg exchange thermometry. In the higher grade rocks, the oxygen isotope and garnet-biotite thermometry yield results which disagree by about 100°C. The highest temperatures recorded by oxygen isotope thermometry, 595°C, are at least 60°C below the minimum temperatures required by phase equilibria. These discrepancies appear to result from pervasive equilibrium retrograde exchange of oxygen isotopes between coexisting minerals. In addition, there are problems with calibration of garnet-biotite thermometry at higher temperatures. Retrograde oxygen isotope exchange may be a general characteristic of high-grade metamorphic rocks and oxygen isotope thermometry may not usually record peak metamorphic temperatures if they significantly exceed 600°C. 相似文献
Temperature estimates based upon
15.
Hydrogen Isotope Study of Fluid Inclusions in Vein Quartz of the Hishikari Gold Deposits, Japan 总被引：1，自引：0，他引：1
Abstract: The origin of mineralizing fluids responsible for the Hishikari vein-type epithermal Au deposits was studied on the basis of the hydrogen isotopic ratio (δD) of the inclusion fluid from vein quartz and adularia. The origin of hydrothermal fluids was estimated by combination of the present δ values and the oxygen isotopic ratios (δ18O) previously reported by Shikazono and Nagayama (1993). The water in the fluid inclusions was extracted by means of decrepitation of quartz at 500°C. Hydrogen was obtained by reduction of the collected water with Zn shot at 450°C. The δD values were determined by mass spectrometer. The δD values of inclusion fluid obtained from quartz range from –61 to –114%. These are significantly lower than the δD value of the thermal water presently venting from the Hishikari deposits and that of local meteoric water. Hydrogen isotopic fractionation between water and amorphous silica, which might have initially precipitated from the hydrothermal fluids at least partly, is not a probable cause of this isotopic depletion, while some water might have been released from the initial hydrous amorphous silica during recrystallization to quartz observed presently. Thus, a part of ore fluids for the Hishikari deposits is supposed to have been originated from the water having anomalous δD values of lower than –100%. Such D depletion cannot be caused by simple oxygen-shift of meteoric water or by contribution of magmatic volatiles. The δD values of water released from the shale samples of the Shimanto–Supergroup, a major host to the Hishikari veins range from –132 to –148%. Therefore, the anomalous δD values of inclusion fluids from some vein quartz and adularia suggest that the water released from hydrous minerals of the sedimentary basement rocks by dehydration or the groundwater isotopically exchanged with sedimentary rocks at elevated temperatures during circulation, partly contributed to the hydrothermal fluids responsible for the Hishikari deposits. 相似文献
16.
西藏昂仁县罗布真金银矿位于冈底斯成矿带西段,其大地构造位置属于南拉萨微陆块,矿体受北西西的断裂构造控制,呈脉状、透镜状产于始新世帕那组火山岩中。按照矿石工业类型分类,矿石类型可分为角砾岩型、石英脉型和蚀变岩型等三类,主要金银矿石矿物为自然金和碲银矿等。矿区广泛繁育不同特征的热液脉体,通过系统的野外观测以及全面的岩相学研究,依据矿物共生组合、脉体切穿关系及蚀变特征,将热液脉体从早到晚划分为石英-黄铁矿阶段(S1)的石英-黄铁矿大脉、玉髓华石英-金-多金属硫化物阶段(S2)的石英-金属硫化物网脉、石英-碳酸盐矿物阶段(S3)的石英-方解石细脉。罗布真金银矿床热液脉体主要发育气液两相流体包裹体(富液两相包裹体、富气两相包裹体)和含子矿物(碳酸盐矿物)三相流体包裹体。本文在野外地质调查的基础上,对不同成矿阶段的石英脉进行了流体包裹体的岩相学观测、显微测温、成分分析以及H-O同位素测试。S1阶段流体包裹体的形成温度集中在310~330 ℃,盐度(w(NaCleq))集中在5.0%~10.1%,密度介于0.60~0.80 g/cm3;S2阶段流体包裹体的形成温度集中在240~280 ℃,盐度介于3.0%~7.0%,密度介于0.70~0.90 g/cm3;S3阶段流体包裹体的形成温度集中在121~215 ℃,盐度集中在1.0%~5.0%,密度集中在0.85~1.00 g/cm3。拉曼分析表明,罗布真金银矿的流体包裹体成分以H2O为主,并含有少量的CO2、N2、CH4等气体及方解石子晶。各热液脉体石英中流体包裹体的δ${{\text{D}}_{{{\text{H}}_{2}}\text{O},\text{V-SMOW}}}$值的变化范围为-106.1‰~-97.5‰,δ18${{\text{O}}_{{{\text{H}}_{2}}\text{O},\text{V-SMOW}}}$值的变化范围为-7.33‰~-7.13‰,展示其成矿流体主要源自火山岩围岩中的循环地下水,在早阶段还有少量岩浆水的加入。成矿流体在岩浆作用驱动下,沿着断裂从深部封闭体系运移到浅部的开放体系,迅速突破临界状态减压沸腾并产生相分离导致金属硫化物沉淀,形成矿化。随着含矿热液成矿物质及金属硫化物的大量析出,流体温度、盐度迅速降低,金属矿物成矿作用随之结束。罗布真金银矿床的成矿流体为中低温、低盐度、中低密度并含有少量CO2、N2、CH4等气体的流体,具有典型的浅成低温热液矿床成矿流体的特征。 相似文献
17.
花岗伟晶岩石英流体包裹体中的短链羧酸 总被引：5，自引：1，他引：4
用离子色谱法研究了某些花岗伟晶岩中石英流体包裹体浸取液的短链送终酸（甲酸、乙酸、丙酸和草酸）和无机阴离子（氟、氯和硫酸根离子）组成,同时进行了矿物包裹体流体的氢和石英的氧同位素成分测定以及显微计温学研究。结果表明,北京延庆大庄科花岗伟晶岩的石英流体包裹体浸取液中含有少量的甲酸和乙酸。花岗岩演化晚期－伟晶岩阶段的高温水热流体中可以存在短链羧酸。 相似文献
18.
Calc-silicate granulites from the Bolingen Islands, Prydz Bay, East Antarctica, exhibit a sequence of reaction textures that have been used to elucidate their retrograde P–T path. The highest temperature recorded in the calc-silicates is represented by the wollastonite- and scapolite-bearing assemblages which yield at least 760°C at 6 kbar based on experimental results. The calc-silicates have partially re-equilibrated at lower temperatures (down to 450°C) as evidenced by the successive reactions: (1) wollastonite + scapolite + calcite = garnet + CO2 , (2) wollastonite + CO2 = calcite + quartz, (3) wollastonite + plagioclase = garnet + quartz, (4) scapolite = plagioclase + calcite + quartz, (5) garnet + CO2 + H2 O = epidote + calcite + quartz, and (6) clinopyroxene + CO2 + H2 O = tremolite + calcite + quartz.
The reaction sequence observed indicates that a CO2 was relatively low in the wollastonite-bearing rocks during peak metamorphic conditions, and may have been further lowered by local infiltration of H2 O from the surrounding migmatitic gneisses on cooling. Fluid activities in the Bolingen calc-silicates were probably locally variable during the granulite facies metamorphism, and large-scale CO2 advection did not occur.
A retrograde P–T path, from the sillimanite stability field ( c. 760°C at 6 kbar) into the andalusite stability field ( c. 450°C at <3 kbar), is suggested by the occurrence of secondary andalusite in an adjacent cordierite–sillimanite gneiss in which sillimanite occurs as inclusions in cordierite. 相似文献
The reaction sequence observed indicates that a CO
A retrograde P–T path, from the sillimanite stability field ( c. 760°C at 6 kbar) into the andalusite stability field ( c. 450°C at <3 kbar), is suggested by the occurrence of secondary andalusite in an adjacent cordierite–sillimanite gneiss in which sillimanite occurs as inclusions in cordierite. 相似文献
19.
湘西北花垣矿集区位于扬子地台东南缘,是湘西-鄂西成矿带上最典型的超大型铅锌矿床所在地.通过对花垣矿集区典型铅锌矿床流体包裹体显微测温、成分分析及C、H、O同位素研究,结果表明,该区铅锌矿床闪锌矿与方解石中流体包裹体的均一温度范围集中在120~200℃,盐度范围集中在8%~20% NaCleqv.流体中液相离子成分主要为Ca2+、Na+、Mg2+、SO42-、Cl-,气相成分主要为H2O、N2和CO2及少量的CO、CH4和H2.流体的δDSMOW值范围为-60.4‰~-33.0‰,δ18O流体值范围为3.8‰~9.2‰.以上流体包裹体和稳定同位素分析结果表明,花垣矿集区铅锌矿床的成矿流体具有热卤水的性质,主要来源于建造水和大气降水.成矿期方解石的δ13CPDB值范围为-4.89‰~0.57‰,δ18OSMOW值范围为13.37‰~21.73‰,略低于碳酸盐围岩,说明成矿流体中的碳主要来源于碳酸盐围岩的溶解作用.矿石沉淀机制可能为两种流体的混合,即来自深部的富含金属物质的热卤水与富含有机质和硫酸盐的建造水及下渗大气降水的混合导致了铅锌矿石的沉淀.对地质和地球化学资料的综合结果表明,花垣矿集区铅锌矿床属于密西西比河谷型（MVT）铅锌矿床. 相似文献
20.
The oxygen isotope and trace element composition of hydrothermal quartz has been integrated with scanning electron microscope-cathodoluminescence (SEM-CL) images and fluid inclusion properties to track fluid sources and hydrothermal processes in the Mt. Leyshon Au deposit, Australia. Oxygen isotope and trace element data were collected on parallel traverses across the same quartz sections, using secondary isotope mass spectrometry (SIMS) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), respectively, with SEM-CL images obtained before analysis for petrographic context. Over the 280 to 650 °C quartz precipitation range suggested by fluid inclusion microthermometry, δ18Oquartz varies from 0.0 to 14.4‰, corresponding to a wide range of equilibrium δ18Ofluid values, from-6.1 to 10.2‰ (vs. V-SMOW). The δ18Oquartz signature varies systematically among distinct SEM-CL quartz generations (both within and between samples), and can be correlated with variations in temperature and fluid composition, but is independent of intra-generational oscillatory zoning. In contrast, Al and Li concentrations correlate broadly with CL intensity in oscillatory quartz, whereas their concentration is unpredictable in sealed fractures and overgrowths. Concentrations of B, Mg, Na, P, Cl, K, Ti, Mn, Fe, Ge, and Sn are independent of Al, Li, and oscillatory CL features, but Ti correlates with quartz precipitation temperature. Although no systematic correlation between δ18Oquartz and trace element concentrations was found, complementary patterns exist in narrow overgrowths of low δ18Oquartz ( 0‰) and high Al (> 10,000 ppma). These quartz zones likely formed during the incursion of 18O-depleted meteoric water into the magmatically-dominated Mt. Leyshon hydrothermal system. We interpret the highest Al concentrations as the result of high quartz precipitation rates, triggered by depressurisation of the hydrothermal cell. The decoupling of oxygen isotope and trace element patterns in quartz leads to the suggestion that (1) under most circumstances, temperature and fluid chemistry dominate δ18Oquartz, and (2) the trace element record, and in particular Al and Li, is influenced by the superimposed effects of quartz precipitation rate. 相似文献