新疆哈密卡拉塔格铜(锌)矿红石幅1∶50 000矿产地质图数据库

新疆哈密卡拉塔格铜(锌)矿红石幅(K46E009008)1∶50 000矿产地质图数据库是根据《固体矿产地质调查技术要求(1∶50 000)》(DD2019-02)和行业其他标准及要求,在充分利用1∶200 000、1∶50 000等区域地质调查工作成果资料的基础上,采用数字填图系统进行野外地质专项填图,并应用室内与室外填编图相结合的方法完成。本数据库将中-上奥陶统荒草坡群大柳沟组、下志留统红柳峡组和卡拉塔格组的建造类型进行了重新划分,把图幅内侵入岩时代划分为志留纪、泥盆纪、二叠纪等3期,建立了岩浆岩演化序列。图幅区内有大中小型矿床和矿点共8个,成矿时代集中分布在志留纪、石炭纪,赋矿围岩为火山碎屑岩和次火山岩,该区优势矿产以铜锌金为主,矿床类型以VMS型和次火山热液脉型矿床为主,分布在图幅东南一带。除金属矿产外,尚有膨润土矿床产出,具有较好的找矿潜力。本数据库包含5个地层单位和3期岩浆岩资料,数据量约为 15.1 MB。这些数据充分反映了该图幅 1∶50 000 矿产地质调查示范性成果,对该区矿产资源研究和勘查等具有参考意义。     

Relative contribution of magmatic and post-magmatic processes in the genesis of the Thompson Mine Ni-Co sulfide ores,Manitoba, Canada

The Ni-Co-(PGE) sulfide deposits of the Thompson Nickel Belt (TNB) in Northern Manitoba, Canada are part of the fifth largest nickel camp in the world based on contained nickel; past production from the TNB deposits is 2500 kt Ni. The Thompson Deposit is located on the eastern and southern flanks of the Thompson Dome structure, which is a re-folded nappe structure formed during collision of the Trans-Hudson Orogen with the Canadian Shield at 1.9–1.7 Ga. The Thompson Deposit is almost entirely hosted by P2 member sulfidic metasedimentary rocks of the Paleoproterozoic Ospwagan Group. Variably serpentinised and altered dunites, peridotites and pyroxenites contain disseminated sulfides and have a spatial association with sediment-hosted Ni sulfides which comprise the bulk of the ore types. These rocks formed from rift-related komatiitic magmas that were emplaced at 1.88 Ga, and subsequently deformed by boudinage, thinning, folding, and stacking.Disseminated sulfide mineralization in the large serpentinised peridotite and dunite intrusions that host the Birchtree and Pipe Ni-Co sulfide deposits typically has 4–6 wt% Ni in 100% sulfide. The disseminated sulfides in the less abundant and much smaller boudinaged serpentinised peridotite and dunite bodies associated with the Thompson Deposit have 7–10 wt% Ni in 100% sulfide. The majority of Thompson Mine sulfides are hosted in the P2 member of the Pipe Formation which is a sulfidic schist developed from a shale prololith; the mineralization in the schist includes both low Ni tenor (<1 wt% Ni in sulfide) and barren sulfide (<200 ppm Ni) and a Ni-enriched sulfide with 1–18 wt% Ni in 100% sulfide. The semi-massive and massive sulfide ores show a similar range in Ni tenor to the metasediment-hosted mineralization, but there are discrete populations with maximum Ni tenors of ∼8, 11 and 13 wt% Ni in 100% sulfide. The variations in Ni tenor are related to the Ni/Co ratio (high Ni/Co correlates with high Ni tenor sulfide) and this relationship is produced by the different Ni/Co ratios in sulfides with a range in proportions of pyrrhotite and pentlandite. Geological models of the ore deposit, host rocks, and sulfide geochemical data in three dimensions reveal that the Thompson Deposit forms an anastomosing domain on the south and east flanks of a first order D3 structure which is the Thompson Dome. In detail, a series of second order doubly-plunging folds on the eastern and southern flank control the geometry of the mineral zones. The position of these folds on the flank of the Thompson Dome is a response to the anisotropy of the host rocks during deformation; ultramafic boudins and layers of massive quartzite in ductile metasedimentary rocks control the geometry of the doubly-plunging F3 structures. The envelope of mineralization is almost entirely contained within the P2 member of the Pipe formation, so the deposit is clearly folded by the first order and second order D3 structures. The sulfides with highest Ni tenor (typically >13 wt% Ni in sulfide) define a systematic trend that mirrors the configuration of the second order doubly-plunging F3 structures on the flanks of the Dome. Although moderate to high Ni tenor mineralization is sometimes localized in fold hinges, more typically the highest Ni tenor mineralization is located on the flanks of the fold structures.There is no indication of the mineralogical and geochemical signatures of sedimentary exhalative or hydrothermal processes in the genesis of the Thompson ores. The primary origin of the mineralization is undoubtedly magmatic and this was a critical stage in the development of economic mineralization. Variations in metal tenor in disseminated sulfides contained in ultramafic rock indicate a higher magma/sulfide ratio in the Thompson parental magma relative to Birchtree and Pipe. The variation in Ni tenor of the semi-massive and massive sulfide broadly supports this conclusion, but the variations in metal tenor in the Thompson ores was likely created partly during deformation. The sequence of rocks was modified by burial and loading of the crust (D2 events) to a peak temperature of 750 °C and pressure of 7.5 kbar. The third major phase of deformation (D3) was a sinistral transpression (D3 event) which generated the dome and basin configuration of the TNB. These conditions allowed for progressive deformation and reformation of pyrrhotite and pentlandite into monosulfide solid solution as pressure and temperature increased; this process is termed sulfide kinesis. Separation of the ductile monosulfide solid solution from granular pentlandite would result in an effective separation of Ni during metamorphism, and the monosulfide solid solution would likely be spread out in the stratigraphy to form a broad halo around the main deposit to produce the low Ni tenor sulfide. Reformation of pentlandite and pyrrhotite after the peak D2 event would explain the broad footprint of the mineral system. The effect of the D3 event at lower pressure and temperature would have been to locally redistribute, deform, and repeat the lenses of sulfide.The understanding of the relationships between petrology, stratigraphy, structure, and geochemistry has assisted in formulating a predictive exploration model that has triggered new discoveries to the north and south of the mine, and provides a framework for understanding ore genesis in deformed terrains and the future exploration of the Thompson Nickel Belt.     

大岭子金矿地质特征及选矿浸出率

大岭子金矿V1矿体赋存于中元古界高黎贡山群变质岩中,受韧性剪切带控制,矿石类型以氧化矿石为主。提出选矿依据。     

东天山双龙铜矿石英闪长岩锆石U-Pb定年、Hf同位素分析及对构造环境的制约

通过对新疆东天山雅满苏岛弧带双龙铜矿成岩地质特征、岩石地球化学特征及Hf同位素分析,认为赋矿岩体为一套形成于后碰撞环境下的准铝质高钾钙碱性岩石系列的石英闪长岩,LA-ICP-MS锆石U-Pb同位素年龄为(300.9±1.2)Ma。岩石地球化学显示,赋矿岩石具富集大离子亲石元素(LILE)K,Rb等及高场强元素(HFSE)Th,U,Zr和Hf,贫Nb,Ta,Ti,Sr,P特征,可能形成于后碰撞构造环境。石英闪长岩锆石176Hf/177Hf变化范围0.282949~0.283002,平均值0.282979,εHf(t)值为12.32~14.40,平均13.40,tDM2(Hf)为375~482Ma,平均429Ma,表明岩浆物源可能来自志留纪新生地壳的部分熔融。     

云南巍山小纪罗异常区铜多金属矿找矿思路

小纪罗异常反映低温热液活动元素的主异常。已发现2个铜矿点。讨论异常区成矿围岩条件、矿化类型,分析矿化与构造、岩体之间的关系,为下一步铜多金属找矿工作提供思路。     

云南景东文玉火山热液型铜矿

铜矿赋存在三叠系上统小定西组火山岩系中,岩浆期后热液对矿质的运移、改造、叠加起重要作用。矿床具中低温火山热液蚀变特征。     

Geochronology and mineralogy of the Weishan carbonatite in Shandong province,eastern China

The Weishan REE deposit is located at the eastern part of North China Craton (NCC), western Shandong Province. The REE-bearing carbonatite occur as veins associated with aegirine syenite. LA-ICP-MS bastnaesite Th-Pb ages (129 Ma) of the Weishan carbonatite show that the carbonatite formed contemporary with the aegirine syenite. Based on the petrographic and geochemical characteristics of calcite, the REE-bearing carbonatite mainly consists of Generation-1 igneous calcite (G-1 calcite) with a small amount of Generation-2 hydrothermal calcite (G-2 calcite). Furthermore, the Weishan apatite is characterized by high Sr, LREE and low Y contents, and the carbonatite is rich in Sr, Ba and LREE contents. The δ¹³C_V-PDB (−6.5‰ to −7.9‰) and δ¹³O_V-SMOW (8.48‰–9.67‰) values are similar to those of primary, mantle-derived carbonatites. The above research supports that the carbonatite of the Weishan REE deposit is igneous carbonatite. Besides, the high Sr/Y, Th/U, Sr and Ba of the apatite indicate that the magma source of the Weishan REE deposit was enriched lithospheric mantle, which have suffered the fluid metasomatism. Taken together with the Mesozoic tectono-magmatic activities, the NW and NWW subduction of Izanagi plate along with lithosphere delamination and thinning of the North China plate support the formation of the Weishan REE deposit. Accordingly, the mineralization model of the Weishan REE deposit was concluded: The spatial-temporal relationships coupled with rare and trace element characteristics for both carbonatite and syenite suggest that the carbonatite melt was separated from the CO₂-rich silicate melt by liquid immiscibility. The G-1 calcites were crystallized from the carbonatite melt, which made the residual melt rich in rare earth elements. Due to the common origin of G-1 and G-2 calcites, the REE-rich magmatic hydrothermal was subsequently separated from the melt. After that, large numbers of rare earth minerals were produced from the magmatic hydrothermal stage.     

云南绿春杨家寨金多金属矿矿床特征及成矿规律

杨家寨金多金属矿位于西藏—三江造山系,兰坪—普洱双向弧后陆内盆地与绿春陆缘弧带结合部,矿体近矿围岩主要为下二叠统高井朝组安山质凝灰岩及安山岩,少部分为石英斑岩,矿体就位于与莫马洛断层（F4）成锐角度相交的次级构造、层间破碎带及层间剥离—滑脱构造带.成矿作用共分三个阶段：早二叠世晚期——矿源岩（层）形成阶段,燕山早期——矿床形成阶段;燕山晚期——矿床定位阶段.矿床类型为浅成低温热液构造—蚀变岩型多金属矿床.     

老挝帕莱通铁矿地质特征及找矿潜力

老挝帕莱通铁矿,矿体呈层状似层状,以出现多层矿产于中—晚三叠统基性火山岩系中,该铁矿为火山活动的直接产物.矿区显示了较好的找矿前景.尤其是矿区东部及其外围找矿潜力巨大,深部玄武岩喷发间断面之隐伏矿也有较好的找矿前景.矿区中东部除寻找Fe以外,也是Cu多金属矿形成的有利地段.     

云南省施甸县东山铅锌矿成因分析

云南省施甸县东山铅锌矿为一中型铅锌矿床.矿体赋存于二叠系沙子坡组,主要受近SN向的区域断裂F2和F18及次级断裂构造控制,岩石（性）控矿也十分明显,成矿与构造、深部断裂、岩浆热液活动密切相关.成矿地质背景及成矿地质条件有利,通过对矿床成因分析,展示了矿区较好的找矿前景和资源潜力.