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1.
铜陵中酸性侵入岩成因及锆石SHRIMP定年 总被引：15，自引：7，他引：8
铜陵地区高钾钙碱性系列侵入岩包括辉长闪长岩+石英二长闪长岩+花岗闪长岩,橄榄安粗岩系列侵入岩包括辉石二长闪长岩+二长岩+石英二长岩。高钾钙碱性系列侵入岩中含有富云母包体和微粒闪长质包体以及镁铁质石英二长闪长质包体,与区内的铜(金)矿化关系密切;橄榄安粗岩系列岩体中含多种深源堆积岩包体,与金(铜)、银、铅、锌等矿化关系密切。锆石SHRIMP定年结果表明,石英二长闪长岩为140Ma左右,花岗闪长岩为142～146Ma,辉长闪长岩为143Ma,辉石二长闪长岩为138～142Ma,二长岩为143Ma,可见两个系列侵入岩的年龄既有一定的差别,也有一些重叠。岩石地球化学及包体岩石学研究表明,橄榄安粗岩系列岩石可能为幔源碱性玄武质岩浆分异后形成,高钾钙性系列岩石可能为分异的幔源岩浆与壳源岩浆混合后形成。 相似文献
2.
羌塘错尼地区新生代火山岩研究 总被引：7，自引：0，他引：7
同位素年代学、岩石学、矿物化学和岩石地球化学特征研究表明,羌塘错尼地区火山岩可以划分为3套岩石组合：①高钾钙碱性火山岩(44Ma～38Ma);②钾玄岩质火山岩;③强碱性火山岩(34Ma～19Ma)。3套火山岩均是大陆碰撞造山后期岩浆作用的产物,始新世以来,随着该区由碰撞、挤压作用发展到出现走滑,应力环境由挤压转变为张性,导致依次喷发高钾钙碱性火山岩、钾玄岩质火山岩和强碱性火山岩。强碱性火山岩的地球化学特征暗示了岩浆源区受到过地幔流体的强烈交代作用。 相似文献
3.
4.
铜陵矿集区燕山期中酸性侵入岩地球化学特征及其地质意义 总被引：12，自引：2，他引：12
铜陵矿集区燕山期中酸性侵入岩由橄榄玄粗质系列和高钾钙碱性系列岩石组成,两者的岩石化学和地球化学特征存在差异,相互间不存在岩浆分异演化关系.稀土和微量元素以及O、Pb、Sr、Nd同位素研究表明,高钾钙碱性系列侵入岩的原始岩浆以下地壳深变质岩部分熔融岩浆为主,在有幔源玄武质岩浆注入的情况下先于橄榄玄粗质系列岩浆侵位形成;起源于富集地幔的碱性玄武岩与有限的地壳物质发生同化混染并通过结晶分异作用(AFC)形成了橄榄玄粗质系列侵入岩.下地壳或岩石圈地幔拆沉继而环流热幔上涌是本区侵入岩形成的直接起因;同时,侵入岩浆的强烈活动也是本区构造环境由挤压向伸展转换的标志. 相似文献
5.
南澜沧江结合带火山岩岩浆成因——洋脊洋岛与弧岩浆作用的性质 总被引：10，自引：1，他引：9
在对滇西南昌宁—孟连带石炭—二叠纪火山岩和南澜沧江带二叠—三叠纪火山岩的微量元素和稀土元素研究的基础上,划分了岩浆作用类型和岩浆演化系列,探讨了岩浆源区成分特点。昌宁—孟连带玄武质岩浆的演化主要受部分熔融和分离结晶作用控制;这些岩浆可以划分为３个岩浆演化系列：（１）稀土曲线平坦型的洋脊型拉斑玄武岩浆演化系列,其岩浆起源于亏损型地幔;（２）稀土曲线中等富集型的准洋脊型拉斑玄武岩浆演化系列,其岩浆起源于过渡型地幔;（３）稀土曲线强烈富集型的洋岛型碱性玄武岩浆演化系列,其岩浆起源于富集型地幔。南澜沧江带弧火山岩的岩浆成因主要受分离结晶作用控制,也可以划分为３个岩浆演化系列：（１）二叠纪低钾拉斑—中钾钙碱性岩浆演化系列;（２）中南段的晚三叠世低钾拉斑—中钾钙碱性岩浆演化系列;（３）北段的晚三叠世钾玄岩—高钾钙碱性岩浆演化系列 相似文献
6.
安徽铜陵矿集区出露的侵入岩可划分为高钾钙碱性和橄榄安粗岩系列,作为铜陵7大矿田之一的焦冲地区是否也存在两个系列侵入岩?它们的时代及成因与整个铜陵地区的侵入岩是否相同?这些问题目前仍不清楚。本文选择铜陵焦冲矿田的侵入岩开展了岩相学、岩石地球化学、LA-ICPMS锆石U-Pb定年及原位Hf同位素地球化学研究。结果表明,焦冲矿田也存在高钾钙碱性系列和橄榄安粗岩系列侵入岩,前者的主要岩石类型为石英二长闪长岩、花岗闪长岩,后者为辉石二长闪长岩。LA-ICPMS锆石U-Pb定年结果显示,高钾钙碱性系列侵入岩年代与铜陵地区其他矿区同类岩石年代相同,约为142 Ma;而橄榄安粗岩系列侵入岩年代比铜陵地区其他矿区同类岩石年轻,约为136 Ma。总体上看,铜陵地区两个系列侵入岩具有多期次侵位的特征。焦冲高钾钙碱性系列侵入岩含有较多的老的继承性锆石,说明本区古老地壳卷入了岩浆形成过程。结合铜陵地区侵入岩的特征和焦冲矿田侵入岩岩石地球化学研究结果,笔者认为,焦冲矿田两个系列侵入岩成因与铜陵地区侵入岩相似,即橄榄安粗岩系列侵入岩是来自莫霍面附近深部位岩浆房富碱基性岩浆结晶分异后的产物,而高钾钙碱性系列侵入岩是深位岩浆房分异后的岩浆与浅位岩浆房长英质岩浆混合后的产物。 相似文献
7.
铜陵地区铜官山矿田侵入岩锆石SHRIMP定年 总被引：7，自引：0，他引：7
铜陵铜官山矿田的中酸性侵入岩属高钾钙碱性系列,主要岩石类型为石英二长闪长岩和花岗闪长岩。本文对该矿田内的铜官山岩体和天鹅抱蛋岩体进行了锆石的SHRIMPU-Pb定年。结果表明,铜官山和天鹅抱蛋石英二长闪长岩的锆石SHRIMPU-Pb年龄几乎相同,分别为141.8±1.0Ma和141.3±1.3Ma,反映它们是同一次岩浆侵入作用的产物。结合锆石CL分析得出,两岩体中均含有新太古代、古元古代和新元古代岩浆型的继承性锆石核,说明本区岩浆的源岩含有古老的下地壳成分,锆石微量及稀土元素特征也表明其为陆壳而非洋壳成因,结合同位素和包体特征,得出岩浆来自富集地幔并含有古老地壳成分。 相似文献
8.
江山—龙游南部地区晚中生代侵入岩分布广泛,以往被认为是钙碱性系列岩石,笔者通过野外地质、岩石学和元素地球化学研究表明,石英二长岩、二长岩、正长岩以及与之伴生的花岗岩与花岗斑岩属钾玄质系列岩石。这套岩石高碱(Na2O K2O=7.80%～10.47%)、富钾(K2O/Na2O=0.92～1.91)、贫钛(TiO2=0.2%～0.88%)、Al2O3含量较高且变化范围大(11.08%～17.77%),富集大离子亲石元素(LILE)和轻稀土元素(LREE),且Ce/Yb(27.29～85.64)、Ta/Yb(0.42～0.73)和Th/Yb(3.44～14.44)比值高,具有钾玄质系列的岩石地球化学特征。该区矿产资源较为丰富,矿床在时间与空间上多与钾玄质侵入岩密切共生,钾玄质侵入岩为成矿母岩,是重要的找矿岩石学标志。 相似文献
9.
扬子岩浆岩带东段基性岩地球化学 总被引：20，自引：7，他引：13
长江中下游中生代岩浆岩带称为扬子岩浆岩带。该带岩浆岩属高钾钙碱性岩系和橄榄安粗岩系,共基性端员玄武岩和辉长岩高钾富碱,硅弱不饱和,富集Ｒｂ、Ｂａ、Ｔｈ、Ｋ、ＬＲＥＥ等强不相容元素,强烈亏损Ｃｒ、Ｎｉ等强相容元素;ＲＥＥ球粒陨石标准化曲线为右倾型,在Ｌａ／Ｓｍ－Ｌａ图上排列成一斜线,是地幔不同程度部分熔融为主的产物。基性岩εＮｄ较高,Ｉｓｒ较低,在εＮｄ－ＩＳｒ图上沿地幔排列及其延长线分布,略向右漂 相似文献
10.
Jiancheng Xie Yu Wang Quanzhong Li Jun Yan Weidong Sun 《International Geology Review》2018,60(11-14):1361-1380
ABSTRACTLarge-scale Cu–Au mineralization is associated with Late Mesozoic intrusive rocks in the Tongling region of eastern China, which mainly comprise pyroxene monzodiorite, quartz monzodiorite, and granodiorite. To constrain the petrogenesis of the intrusive rocks and Cu–Au mineralization, detailed analyses of the geochronology, apatite in situ geochemistry, whole-rock geochemistry, and zircon Hf isotopic compositions were performed. Magmatic zircons from pyroxene monzodiorites, quartz monzodiorites, and granodiorites yield U–Pb ages of 136–149 Ma, 136–146 Ma, and 138–152 Ma, respectively, indicating that their formation ages are contemporaneous. Quartz monzodiorites and granodiorites (SiO2 = 57.9–69.5 wt.%) are highly potassic calc-alkaline rocks with adakitic affinity and have low MgO and Y contents, low zircon εHf(t) values (?11.7 to ?39.0), high apatite Cl contents (>0.2 wt.%), and log fO2 values (?23.2 to ?8.23), indicating that they may have formed when metasomatized mantle-derived magmas mixed with slab-derived magmas before undergoing crustal assimilation and fractional crystallization. Pyroxene monzodiorites (SiO2 = 48.4–53.0 wt.%) are shoshonitic and record high MgO, P2O5, and Y contents, high zircon εHf(t) values (1.55 to ?7.87), high oxygen fugacity, low Nb and Ta contents, and low apatite Cl contents (mainly <0.2 wt.%), suggesting that they were primarily derived from a metasomatized lithospheric mantle-derived magma that experienced the assimilation of lower crustal materials. The results indicate that the intrusive rocks and associated large-scale Cu–Au mineralization of the Tongling region resulted from the partial melting of the subducted oceanic slab in an oxidizing environment. 相似文献
11.
Early Paleozoic batholiths in the northern part of the Kuznetsk Alatau: Composition,age, and sources
S. N. Rudnev S. M. Borisov G. A. Babin O. A. Levchenkov A. F. Makeev P. A. Serov D. I. Matukov Yu. V. Plotkina 《Petrology》2008,16(4):395-419
The paper reports geological, chemical, and geochronological data on the Early Paleozoic granitoid and gabbro-granite associations, which compose the Kozhukhovskii and Dudetskii batholiths in the northern part of the Kuznetsk Alatau. The Kozhukhovskii batholith located in the Alatau volcanoplutonic belt is made up of tholeiitic, calc-alkaline, and subalkaline rocks that were formed in two stages. The first stage corresponded to the formation of granitoids of the Tylinskii quartz diorite-tonalite-plagiogranite complex (～530 Ma, Tylinskii Massif, tholeiitic type) in an island arc setting. The second stage (～500 Ma) produced the Martaiga quartz diorite-tonalite-plagiogranite complex (Kozhukhovskii Massif, calc-alkaline type) and the Krasnokamenskii monzodiorite-syenite-granosyenite complex (Krasnokamenskii Massif, subalkaline type) in an accretionary-collisional setting. The Dudetskii batholith is situated in the Altai-Kuznetsk volcanoplutonic belt and contains widespread subalkaline intrusive rocks (Malodudetskii monzogabbro-monzodiorite-syenite and Karnayul’skii granosyenite-leucogranite complexes) and less abundant alkaline rocks (Verkhnepetropavlovskii carbonatite-bearing alkaline-gabbroid complex), which were formed within the age range of 500–485 Ma. Our Nd isotopic studies suggest mainly a subduction source of the rocks of the Kozhukhovskii batholith (εNd from + 4.8 to + 4.2). Subalkaline rocks of the Dudetskii batholith exhibit wide isotopic variations. The Nd isotopic composition of monzodiorites and monzogabbro of the Malodudetskii Complex (εNd = + 6.6), in association with the elevated alkalinity and high Nb and Ta contents of these rocks, testifies to the predominant contribution of an enriched mantle source at the participation of a depleted mantle source. The lower εNd (from + 3.2 to + 1.9) in its syenites possibly indicates their generation through melting of metabasic rocks derived from enriched mantle protolith. The rocks of the Karnayul’skii Complex have lower Nb and Ta contents at similar εNd (+3.6), which suggests some crustal contribution to their formation. 相似文献
12.
Alexander Deutsch 《Contributions to Mineralogy and Petrology》1984,85(1):45-57
Fortyfive new K-Ar ages and Sr isotope data on amphiboles, biotites, clinopyroxenes and whole rock samples from subvolcanic dykes south of the Tauern Window establish, that alkalibasaltic dykes were intruded 30 m.y. ago and shoshonitic volcanism occured between 30 and 24 m.y. ago. Two calc-alkaline rocks of high-potassium composition yielded ages of 40 and 26 m.y. resp., a spread which may or may not be real. Calc-alkaline dykes with medium and low potassium contain excess argon and are hence undatable. Alkalibasaltic dykes have 87Sr/86Sr ratios of 0.7056–0.7070, shoshonitic rocks 0.7075–0.7133, potassium rich calc-alkaline dykes 0.7077–0.7100. 87Sr/86Sr of all other calc-alkaline rocks scatter between 0.7074 and 0.7150. Sr data indicate that dykes studied do not represent closed Sr systems, but that Sr characteristics result from selective strontium assimilation en route to surface. Primary Sr isotopic ratios of alkalibasaltic dykes point to an origin of these rocks in enriched sub-continental upper mantle. The source region of shoshonitic and high-potassium calcalkaline rocks could have 87Sr/86Sr around 0.707, which is assigned to the input of a component rich in alkalies, LREE and LIL elements. Genetic relationships with other Tertiary magmatites of similar geotectonic position are explained in terms of plate tectonic models of the Eastern Alps. 相似文献
13.
Pleistocene to Recent stratovolcanoes in the Highlands of Papua New Guinea are made up of calc-alkaline to shoshonitic lava, tuff, agglomerate, ash, and lahar deposits. The volcanic rocks are characterized by high and variable Al, high K and total alkalis, and low Fe, Mg, and Ca. There is a continuous variation between high-K calc-alkaline, low-Si high-K calc-alkaline, and shoshonitic rocks. The elements V, Rb, Sr, Zn, Nb, and Ba are high relative to general andesitic abundances, particularly in the shoshonites. The Highlands volcanic rocks originated either in the base of thick sialic crust which is undergoing stabilization after major orogeny and uplift, or more probably, in eclogite sinking through the underlying mantle. Variation in content of K and other incompatible elements was either inherited from the source rocks in the base of the crust, or was produced by zone refining in a thick upper mantle zone containing interstitial fluid rich in these elements. Further variation, mainly in Fe/Mg, Si, and total alkalis, was caused by minor low-pressure crystal fractionation involving olivine, clinopyroxene, and, to a lesser extent, calcic plagioclase. 相似文献
14.
在华北克拉通北缘阴山地块东部固阳地区发现了假白榴石粗面玄武岩和钾质粗面岩两种高钾准铝质碱性火山岩。地质年代学数据显示,假白榴石粗面玄武岩的磷灰石U-Pb年龄为322±14Ma,钾质粗面岩的锆石U-Pb年龄为315.6±7.5Ma,说明其形成时代均为晚石炭世。岩石地球化学特征显示,二者均富Al、Fe,贫Mg;富集大离子亲石元素(如Rb、Ba和K),相对亏损高场强元素(如Ta、Nb和Ti),轻重稀土分异明显,富集轻稀土,相对亏损重稀土,Eu异常不明显;高(87Sr/86Sr)i比值(0.710028~0.714745),低εNd(t)值(-9.0~-17.2),表现出相似的交代岩石圈地幔源区和地壳混染特征。将该碱性火山岩与兴蒙造山带晚石炭世-早二叠世中基性火山岩和阴山地块白垩纪中基性火山岩进行岩石类型对比,发现华北克拉通北缘产出的火山岩多为高钾碱性系列,而兴蒙造山带中产出的火山岩则多为钙碱性系列;与兴蒙造山带晚石炭世-早二叠世中基性火山岩进行岩石成因对比,发现它们的岩浆源区和混染程度并不相同,即固阳地区碱性火山岩为受到早古生代俯冲沉积物交代的岩石圈地幔部分熔融所形成的岩浆在上升过程中混染华北克拉通TTG片麻岩后喷发的产物,而兴蒙造山带中火山岩的产出则多为亏损地幔部分熔融所形成的岩浆在上升过程中轻度混染地壳物质后喷发的结果。在固阳地区发现晚石炭世碱性火山岩,代表着古亚洲洋在该时期的后造山伸展作用范围已延伸至华北克拉通北缘。 相似文献
15.
辽西地区是中国中生代火山岩主要分布区之一。义县组分为4个岩性段。义县火山旋回可分为4个亚旋回。第一亚旋回分为4个小旋回。从早期至晚期，义县旋回火山岩逐渐由基性向中基性、中性和酸性演化，火山岩岩石组合为基性岩-中性岩-酸性岩组合，从北票-义县，火山活动显示了由老到新的迁移性。主要氧化物关系表明岩石的SiO2与K2O呈正相关，SiO2与MgO、CaO、FeO Fe2O3呈负相关。TAS图解反映了火山岩较高碱度的总体特征，硅-碱关系图和AFM图解反映了火山岩属于亚碱性系列中的钙碱性系列岩石，在SiO2-K2O关系图上，绝大部分样品落于高钾钙碱性系列区内，少量落于钾玄岩系列区，因此义县旋回火山岩以高钾钙碱性系列岩石为主，部分为钾玄岩系列，表明岩石富钾。义县旋回火山岩具有大陆板内火山岩的基本特征。 相似文献
16.
Evidence from Muriah, Indonesia, for the Interplay of Supra-Subduction Zone and Intraplate Processes in the Genesis of Potassic Alkaline Magmas 总被引：11，自引：5，他引：6
The high-K alkaline volcano Muriah is situated in central Javaand has erupted two lava series, a younger highly potassic series(HK) and an older potassic series (K). The HK series has higherK2O contents for a given MgO content; greater silica undersaturation;and higher concentrations of LILE (Rb, Sr, Ba, and K), LREE(La and Ce), and HFSE (Nb, Zr, Ti, and P), than the K series.The HK series lavas have incompatible trace element patternssimilar in many respects to ocean island basalts. The K serieshas slightly higher 87Sr/86Sr (O70453
[GenBank]
-O70498) and 18O (+6?2to + 8?4%o) and lower 143Nd/144Nd (0?512530–0?5126588)than the HK series (for which 87Sr/86Sr = 0?70426–0?70451,<518O = +6?52 to +7–0%o, and 1*3Nd/1*4Nd= 0?512623–0?512679),and higher LILE/HFSE and LREE/ HFSE ratios. A7/4 and A8/4 arehigh and do not show any systematic change from the K to theHK series. The proposed model for the Muriah lavas involvesthree source components: (1) the astheno-sphere of the mantlewedge of the Sunda arc, which has Indian Ocean MORB characteristics;(2) a metasomatic layer situated at the base of the lithosphere,which has characteristics similar to enriched mantle (i.e.,EMU); (3) subducted pelagic sediments from the Indian Ocean. Trace element and isotope data indicate that the characteristicsof the K series are produced by mixing of two endmember magmas:an undersaturated magma derived wholly from within-plate sourcesand a calc-alkaline magma derived from the subduction-modifiedasthenospheric mantle. The calc-alkaline magma is believed tobe contaminated by the arc crust before mixing. Low-pressurefractionation took place in the K series after mixing. Initiallithospheric extension in the Bawean trough (in which Muriahis located), may be responsible for decompressive melting ofthe metasomatic layer and thus the production of the HK serieslavas. The magmas erupted from Muriah show a transition fromintraplate to subduction zone processes in their genesis. 相似文献
17.
新疆新源县城南石炭纪火山岩岩石学和元素地球化学研究 总被引：14，自引：0，他引：14
新疆新源县南部那拉提山北坡出露的石炭纪火山岩主要由玄武岩、玄武质粗面安山岩、粗面安山岩、安山岩、流纹岩和火山碎屑岩组成。该火山岩中玄武岩属于钙碱性系列，安山质岩石和流纹岩属于高钾钙碱性系列，其中轻稀土轻微富集而重稀土相对亏损，玄武岩富集大离子亲石元素、U、Th和Pb，亏损高场强元素。研究表明，该火山岩岩浆可能是由俯冲板片脱水产生的流体交代地幔楔后，地幔楔发生部分熔融的结果。微量元素模拟计算表明，该玄武岩岩浆可以由石榴石二辉橄榄岩经3％～6％的部分熔融得到；安山质岩浆可由玄武岩岩浆经15％-28％的分离结晶形成。 相似文献
18.
大兴安岭北端塔木兰沟组玄武质岩石的地球化学特征及构造背景 总被引：8，自引：1，他引：8
大兴安岭北部晚侏罗世塔木兰沟组玄武质岩石具有富碱（K2O＋Na2O〉5．45％），高K2O（2．15%-3．75％）、K2O／Na2O（0．48-1．12）和高的Th／Ta、Ce／Nb、Ta／Nb比值，以及强烈富集大离子亲石元素（LILE）和轻稀土元素（LKEE）的特征，属于钾玄质系列。现有资料分析表明，该钾玄质岩石形成于大陆板内环境。元素地球化学特征揭示，形成钾玄质岩石的原生岩浆经过强烈的结晶分异作用，并混染了前中生代的基底物质。 相似文献
19.
桂东南富钾岩浆岩岩的Nd同位素组成：华南中生代地幔物质上涌事件 总被引：16，自引：9，他引：16
广西东南部罗容杂岩体由辉长岩－闪长岩－二长岩－正长岩组成，马山由碱性辉长岩－正长岩－花岗闪长岩－花岗岩组成。它们富K、富大离子亲石元素（LIL），无Nb、Ta负异常等特征表明它们是形成于板内环境的钾玄质侵入岩。罗容杂岩体的各种岩石和马山的基性岩的εNd(T)稍低，为－0．6，此岩石单元是由幔源岩浆加热地壳使之熔融的壳源岩浆形成的，并伴有幔源岩浆的混合或交换。此二杂岩体形成于拉张构造环境。地幔物质上涌导致了中生代华南地壳张裂以及华南大规模花岗岩和相关矿床的形成。 相似文献
20.
草桃背矿床白垩纪橄榄玄粗岩与铀成矿关系 总被引：1，自引：0，他引：1
赣南会昌断陷盆地沿石城-寻乌深断裂分布一条白垩纪橄榄玄粗岩系列的火山岩带。草桃背大型铀矿床内出露大富足岩体中-粗粒黑云母花岗岩及早白垩世晚期到晚白垩世早期橄榄玄粗岩系列火山岩。大富足花岗岩体岩石w(SiO2)平均为74.67％,碱总量(w（K2O+Na2O）)平均为7.99％,w(K2O)>w(Na2O),w(CaO)平均为0.54％,w(Al2O3)>w(CaO+Na2O+K2O),属高钾钙碱性岩石系列。橄榄玄粗系列火山岩岩石w(SiO2)为45.78 %~59.78 %,w(K2O+Na2O)平均为7.37%,K2O/Na2O平均为1.02,w(TiO2)平均为0.86%, 全铁质量分数平均为7.09%,属偏碱性橄榄玄粗质火山岩类。草桃背铀矿床赋矿岩性为橄榄玄粗岩、碎裂花岗岩及隐爆角砾岩。赋存于碎裂花岗岩及隐爆角砾岩中铀矿石化学成分,与围岩花岗岩成分相似;赋存于橄榄玄粗岩中铀矿石,Fe2O3+Fe2O、CaO、MgO不同程度地带出,w(SiO2)明显增高,表明橄榄玄粗岩在成矿过程中,通过输出大量Fe、Mg、Ca等阳离子而促进铀离子从含矿溶液中沉淀。草桃背矿床的铀矿化与充填在草桃背火山口的橄榄玄粗岩关系密切,在时间上相近、在空间上相伴、在成生上相关,受橄榄玄粗岩岩浆系列热动力的影响,铀元素发生活化、转移或物质交换而成矿,成岩成矿时代属早白垩世晚期到晚白垩世早期。从草桃背铀矿床岩石学、地球化学及赋矿特征入手,总结了铀成矿是富铀矿的花岗岩基底、北东向构造及火山作用结合的产物,橄榄玄粗岩提供热源,并指出半岭、上寮、小富足等地段是寻找草桃背式铀矿床的极有利地区。 相似文献