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1.
新疆霍什布拉克铅锌矿床地质、地球化学特征研究 总被引：3，自引：3，他引：3
新疆霍什布拉克铅锌矿床的矿体和含矿地层的产状一致,主矿体的矿石具有条带状、纹层状构造,矿石中大量发育霉球状、管状和环带状生物结构,显示出层控、热水沉积成因的特点。含矿地层和矿石样品的主量元素PER图解显示含矿碳酸盐岩以含石膏的灰岩为主,围岩的白云岩化微弱,矿化与硅化关系密切。矿石、含矿碳酸盐岩和页岩、粉砂质灰岩和泥质粉砂岩等碎屑岩具有各自鲜明的微量元素分布特征,上层矿体矿石中较强的富集过渡族元素Ti、V、Cr、Mn、Co、Ni、非活动性元素Zr、Hf及大离子亲石元素Sr和Pb,亏损活动性元素Na、K、Rb、Ba和非活动性元素Nb、Th。其围岩重结晶泥晶灰岩富集Ti、Mn、Ni、Sr和Pb,亏损Na、K、V、Fe、Rb、Ba、Zr、Hf、Nb和Th。下层矿体的围岩页岩和泥质、粉砂质灰岩样品的微量元素分布在平均上地壳线附近,部分样品较明显的富集Ti、V、Cr、Mn、Co、Ni、Rb、Y、Zr和Hf,亏损Na、Fe、Sr、Nb。上层矿体矿石和下层矿体围岩中的部分碎屑岩富集强亲岩浆元素Cr、Co、Ni,且上层矿体矿石的稀土元素分布模式具有强的正Eu异常,部分下层矿体围岩具有较明显的正Eu异常。地质和地球化学特征显示该矿床属于热水沉积矿床中的SEDEX型矿床。 相似文献
2.
Chemical modification of enclave magma by post-emplacement crystal fractionation,diffusion and metasomatism 总被引：3，自引：1，他引：3
Hornblende-bearing microgranitoid enclaves from the Swifts Creek Pluton (SCP), SE-Australia display mineralogical and textural variations from their margins to their centers. Margins are fine grained and display quench textures and are enriched in amphibole, biotite and in some cases magnetite relative to their coarser grained centers. Enclaves of this type and their adjacent granitoid host rocks have been sectioned into 0.3 to 1 cm thick slabs in order to determine the chemical variations associated with these mineralogical changes. The fine grained margins are variably enriched in Ti, Al, Mg, Fe, Mg, K, Rb, Ba, Nb, Y, Sc, V, Ni and the REE up to a factor of three relative to the enclave centers. This enrichment is compensated by a depletion of Si and Zr. Elements like Ca, Na and Sr show less coherent variation from margin to center. Host rocks in immediate contact with these enclaves are depleted in Mg, Na, K, Rb and Ba relative to host rocks that are not exposed to enclaves. No one single process can account for all the variations. Instead, we propose that the chemical variations are related to a combination of in situ crystal fractionation of isolated magma globules, mass transfer by diffusion and metasomatic exchange. 相似文献
3.
Robert Cullers 《Lithos》1988,21(4):301-314
A series of soil and stream sediments developed during intense weathering on the metaluminous Danburg granite, northeastern Georgia, U.S.A., have been analyzed mineralogically and chemically. The concentrations of Ba, Na, Rb and Cs in the silt and coarser fractions are controlled mainly by feldspars and biotite. Hf is controlled by zircon, and the REE (rare-earth elements) and Th are largely controlled by sphene. Variations in feldspar, sphene and zircon may produce small variations in Eu/Sm and La/Lu ratios. Ferromagnesian minerals control Ta, Fe, Co, Sc and Cr concentrations.
The mineralogical and chemical composition of the Danburg granite is more closely reflected in the silt than in the sand or gravel fractions of stream sediments. In the silt, the contents of Rb, REE, Th, Ta, Fe, Co and Sc and the ratios of La/Sc, Th/Sc, La/Co, Th/Co, Eu/Sm and La/Lu are similar to those in the unweathered granite. In contrast, these element contents or ratios in the sands and gravels are 0.05−3× the concentration in the unweathered granite. Ta and Ba contents are an exception to the above. The Ta and Ba contents of the sands and gravels are similar to those of the granite.
In the kaolinite-halloysite clays, the content of Na is depleted relative to the source. Rb, Cs, Ba, Hf and Ta are depleted or enriched in the clays relative to the source, while the REE, Th, Fe, Co, Sc and Cr are enriched. The Eu/Sm (Eu anomaly size) and La/Lu ratios, and the REE patterns of the clays are similar to those of the source.
Thus, the mineralogy and element contents of a siltstone developed from metaluminous, granitic sources during intense weathering would be expected to be more similar to the source rock than the sandstones and conglomerates. Claystones should contain similar REE patterns and Eu/Sm ratios as the source rock, but such fine-grained sediments might represent much larger areas of source rocks than the more locally derived sandstones or conglomerates. 相似文献
4.
通过对龙王山灰白色细粒石英闪长岩和灰白色细粒二长花岗岩样品进行LA-ICP-MS锆石U-Pb测年结果属于晚志留世侵入岩。岩石地球化学特征表明,为高钾过铝质-准铝质碱钙性岩;稀土元素Eu具有弱负异常特征;微量元素中Ta、Nb、gr、Sr、Ti、P相对贫化,Rb、Th、Hf、Ba、Sc、K、Ce、Nd、Sm含量相对富集。Rb／Sr平均值为0．30,介于上地幔值与地壳值之间,反映出壳幔源的特点,为s型花岗岩。综合分析该期花岗岩是弧陆碰撞向陆陆碰撞转化阶段构造背景下形成的同碰撞花岗岩。 相似文献
5.
白银厂矿田早中寒武世火山岩地球化学及成因分析 总被引：16，自引：3，他引：13
白银厂矿田早中寒武世火山岩主要为玄武岩－碱性玄武岩－安山岩－玄武安山岩－玄武粗安岩－英安流纹岩－流纹岩。其中基性和中基性岩类为碱性系列和亚碱性系列,碱性玄武岩主要为钾质玄武岩系列。酸性岩类为钙碱性系列。岩石全碱含量平均为５．７６％,Ｋ２Ｏ／,Ｋ２Ｏ／Ｎａ２〈１,Ｆｅ２Ｏ／ＦｅＯ平殚为０．７４;ＴｉＯ２绝大部分样品含量小于１％（在酸性火山岩中含量较低：０．２％～０．８３％,平均为０．５３％;基性和中 相似文献
6.
CHARACTERISTICS OF VOLCANIC ROCKS AND ITS TECTONIC SETTING IN WESTERN PART OF LAZHULONG-JINSAJIANG STRUCTURAL BELT 相似文献
7.
Mineralization of pegmatites in parts of the Oban Massif, Southeastern Nigeria： A preliminary analysis 总被引：1，自引：0，他引：1
The Oban Basement Massif of southeastern Nigeria is composed of metamorphosed rocks including phyllites, schists, gneisses and amphibolites cut by pegmatitic dykes of varying length and thickness, which intruded the metamorphic rocks. Preliminary geochemical study and analysis of these pegmatites from western Oban Massif at Uyanga, Akwa Ibami, Iwuru I, Iwuru Ⅱ and Igbofia showed that the pegmatites are highly albitized. This is incon-sistent with earlier postulations that the pegmatites in this part of Nige... 相似文献
8.
LA-ICP-MS锆石U-Pb测年结果表明,研究区中生代火山岩可分为2期,分别是早白垩世早期（约144Ma）吉祥峰组流纹岩类和早白垩世晚期（约125Ma）上库力组流纹岩类与梅勒图组玄武岩类。早白垩世早期吉祥峰组流纹岩富硅、富碱、富钾（K2O/Na2O〉1）,富集轻稀土元素和Rb、Th、U等元素,亏损重稀土元素、高场强元素（Nb、Ta、Ti）及Sr、P,具有A型流纹岩的特征,暗示其形成于伸展环境。早白垩世晚期火山岩显示双峰式岩石组合特征,基性端元富碱、高钾,富含轻稀土元素和Rb、Ba,亏损重稀土元素和高场强元素（Nb、Ta、Ti、Y）,类似于钾玄质玄武岩,酸性端元显示A型流纹岩的特征。双峰式火山岩组合的存在暗示其形成于陆内拉张的构造环境。结合区域上中生代火山岩的空间分布规律,认为早白垩世早期火山岩的形成与蒙古-鄂霍次克缝合带的演化有关,早白垩世晚期双峰式火山岩的形成与古太平洋板块向欧亚大陆下的俯冲作用相联系。 相似文献
9.
岩石地球化学分析表明小龙潭斑岩高钾(K_2O/Na_2O=0.85~8.39)、富碱(K_2O+Na_2O=9.05%~12.45%),总体属于钾玄岩系列的岩石。岩石富集Rb、Ba、Th、LREE等大离子亲石元素而亏损Ti、Nb、Ta、HREE等高场强元素,具有较高的ΣLREE/ΣHREE比值和(La/Yb)N比值,具中等程度Eu负异常。从岩石地球化学特征分析,小龙潭富碱斑岩起源于金沙江洋壳俯冲交代作用形成的富集地幔,富碱斑岩可能与Cu、Mu、Ag成矿作用密切相关。 相似文献
10.
Analytical data are presented for the following elements: Cs, Rb, Ba, K, Sr, Ca, Na, Fe, Mg, Cu, Co, Ni, Li, Sc, V, Cr, Ga, Al, Si, La, Y, and Zr. Eight samples were analysed by the spark source method for rare earths, Tl, Pb, Hf, Sn, Nb, Mo, Bi, and In. In addition to data on rhyolitic volcanics, a small number of intermediate volcanics and eugeosynclinal sediments were analysed for comparative purposes. The following features are shown by the trace element data:
- The rhyolitic rocks have consistently lower concentrations of most trace and minor elements when compared with recent estimates of average concentrations in granites. None of the criteria for strong fractionation (e.g. low K/Rb, Ba/Rb and K/Cs ratios) are present.
- The data do not indicate any systematic differences between the rhyolitic lavas and ignimbrites, although the very young rhyolitic pumices are consistently more “basic” in their element concentrations compared to the other rhyolitic analyses.
- The residual glasses (and devitrified matrices) are depleted, relative to the total rock compositions, in Fe, Mg, Ca, Sr, V, Sc, and Al, and enriched in Cs, Rb, K, Ba, and Si. Zr is depleted in the residual glasses separated from rhyolites, but not in the andesitic residual matrices.
- The rare earth fractionation patterns of the rhyolitic and andesitic extrusives are very similar, being intermediate between chondritic and sedimentary patterns i.e., there is no evidence of strong fractionation. The rhyolitic patterns also indicate a slight Eu depletion.
- Comparable trace and minor element behaviour (with the possible exception of Zr) seems to exist through the rhyolite-andesite compositional range. This is supported by the whole rock-residual liquid trends for the various elements studied, which broadly coincide with the observed whole rock trends, both through the rhyolitic-andesitic compositonal range, and within the rhyolitic compositional range.
11.
新疆阿吾拉勒山西段下二叠统陆相火山岩岩石地球化学特征、成因及构造背景 总被引：4，自引：0，他引：4
新疆阿吾拉勒山西段是伊犁石炭-二叠纪裂谷的重要组成部分,本文对该区下二叠统典型的双峰式玄武岩-流纹岩组合进行了系统的岩相学和岩石地球化学研究。岩石整体高Na2O、高Al2O3、低TiO2、富碱。玄武岩富集大离子亲石元素Ba、K、LREE和P,亏损高场强元素Th、U、Ta、Nb。粗面斑岩和流纹斑岩富集大离子亲石元素Rb、K、LREE、高场强元素Th、Zr、Hf,亏损Ta、Nb、Sr、Ti和P。玄武安山玢岩的蛛网图与粗面斑岩和流纹斑岩较为一致,但少量元素的特征与玄武岩相似。玄武岩浆来源于弱亏损地幔,并受到了下地壳物质的混染,而玄武安山玢岩、粗面斑岩和流纹斑岩则可能来源于地壳物质的部分熔融。双峰式火山岩的形成可能与上地幔玄武岩浆的底侵作用有关。裂谷演化导致的陆相火山活动持续到早二叠世晚期达到顶峰,中二叠世以后,构造环境由拉伸转为挤压,裂谷演化趋于终止。该区石炭纪末-早二叠世的裂谷活动与整个天山地区晚古生代的构造演化背景具有一致性。 相似文献
12.
内蒙古东北部额尔古纳地区上护林-向阳盆地中生代
火山岩LA-ICP-MS锆石U-Pb年龄和地球化学特征 总被引：9，自引：5，他引：4
LA-ICP-MS锆石U-Pb测年结果表明,研究区中生代火山岩可分为2期,分别是早白垩世早期(约144Ma)吉祥峰组流纹岩类和早白垩世晚期(约125Ma)上库力组流纹岩类与梅勒图组玄武岩类。早白垩世早期吉祥峰组流纹岩富硅、富碱、富钾(K2O/Na2O>1),富集轻稀土元素和Rb、Th、U等元素,亏损重稀土元素、高场强元素(Nb、Ta、Ti)及Sr、P,具有A型流纹岩的特征,暗示其形成于伸展环境。早白垩世晚期火山岩显示双峰式岩石组合特征,基性端元富碱、高钾,富含轻稀土元素和Rb、Ba,亏损重稀土元素和高场强元素(Nb、Ta、Ti、Y),类似于钾玄质玄武岩,酸性端元显示A型流纹岩的特征。双峰式火山岩组合的存在暗示其形成于陆内拉张的构造环境。结合区域上中生代火山岩的空间分布规律,认为早白垩世早期火山岩的形成与蒙古-鄂霍次克缝合带的演化有关,早白垩世晚期双峰式火山岩的形成与古太平洋板块向欧亚大陆下的俯冲作用相联系。 相似文献
13.
新疆可支塔格蛇绿混杂岩位于青藏高原北缘东昆仑西段,属于木孜塔格-鲸鱼湖大断裂的西延部分。主要由辉橄岩、辉长岩、闪长岩、斜长花岗岩、辉绿岩、玄武岩及硅质岩等组成,形成时代为早石炭世。其中辉橄岩具有高Mg,贫Al,Ca,低硅、低碱的特点,富集相容元素Cr,Ni,Co。稀土总量低,接近于球粒陨石稀土元素总量,以LREE略富集为特征。闪长岩SiO2,K2O含量较低,MsO,CaO,Na2O较高,稀土总量高,∑REE为90．95×10^-6,LREE富集。斜长花岗岩SiO2 69．8％,Na2O〉K2O,K2O／Na2O为0．78,A／CNK为1．68,具有大洋斜长花岗岩的岩石化学特征。闪长岩、斜长花岗岩的微量元素特征相似,表现为大离子亲石元素K,Sr,Rb,Ba相对富集,高场强元素Nb,Ta,Zr,Hf相对亏损。研究表明,辉橄岩来源于亏损的地幔岩,接近于强烈亏损的方辉橄榄岩,而明显不同于结晶分异作用成因的超镁铁质岩石。闪长岩、斜长花岗岩为蛇绿混杂岩的浅色岩组分,是地幔岩浆结晶分异的产物,但可能受到了围岩的混染和后期热液交代影响。 相似文献
14.
Alistair R. Allen 《Contributions to Mineralogy and Petrology》1979,71(1):85-98
Geochemical investigations in the Utralanama Block, an intermediate pressure granulite facies terrain in the Arunta Block, central Australia, has revealed several anomalous features, not consistent with the depletion of granitophile components generally considered to accompany granulite facies metamorphism. However, other geochemical features are indicative of depletion. The mean K2O for the Utralanama Block is exceptionally low relative to most other granulite facies terrains, but Rb contents are comparatively high. Consequently, the mean K/Rb ratio is relatively low for granulite facies terrains as is the mean Ba/Rb ratio, whilst mean K/Sr and Rb/Sr ratios are much higher than usual for such terrains. Only the K/Ba ratio shows equivalent values to depleted terrains elsewhere.Comparison of these ratios for the three main compositional groups of rocks in the Utralanama Block reveals that for mafic rocks all the above ratios are characteristic of extreme depletion, whereas, for all but the K/Ba ratio, mean ratios for the pelitic rocks, and to a lesser extent for the quartzofeldspathic rocks approach normal crustal values or values for metasomatic rocks. The abnormally high Rb/Sr ratios of these rocks compared to average crustal rocks suggest, however, that metasomatism is the cause of the anomalous geochemical features of the Utralanama Block, and this is supported by field and microstructural evidence. Thus, Rb/Sr ratios appear to be useful indicators of metasomatism where no gross mineralogical or microstructural evidence for metasomatism is obvious, and under such conditions the K/Ba ratio may be more reliable than the K/Rb ratio for indicating prior depletion of the terrain. 相似文献
15.
Mohammed Ikramuddin Yemane Asmeron Paul M. Nordstrom Kirk P. Kinart Walter M. Martin Sharon J.M. Digby Danelle D. Elder Walter F. Nijak Adolphus A. Afemari 《Journal of Geochemical Exploration》1983,19(1-3)
Several recent studies have suggested that rocks associated with mineral deposits of hydrothermal origin are generally enriched in Rb. TI is similar in its geochemical characteristics to Rb, but its use as a potential guide to ore deposits has not been suggested. Although TI has the same size and valency as Rb, it is concentrated more in residual melts than Rb and K because the TI-O bond is more covalent and weaker than either the Rb-O or K-O bonds.A new method which is rapid and precise has been developed by one of the authors for the determination of TI in geological materials at the ppb level. About 350 rocks from 4 mineralized areas in northeastern Washington and central Montana were analyzed for TI by this method. Most of these rocks were also analyzed for SiO2, A12O3,Fe2O3, MgO, CaO, Na2O, K2O, TiO2, P2O5, MnO, Ag, As, Au, Ba, Co, Cu, F, Li, Mo, Ni, Pb, Sr, Sb, Sn, Sr, Te, U, W, and Zn. The ore deposits of the areas studied include the gold-silver deposits of the Republic district, the uranium deposit of the Midnite mine, the coppermolybdenum deposit of Mount Tolman, and the gold deposits of the North Moccasin mining district.In all the mineralized areas there is significantly more TI in hydrothermally altered rocks than in unaltered rocks. The very high abundance of TI in the altered rocks of the North Moccasin gold district, and the significant positive correlations of TI and K and TI and Rb in the mineralized rocks of the other three areas suggest that TI was concentrated in hydrothermal fluids. In altered rocks the average K/Rb and K/TI ratios are lower, and the Rb/Sr and TI/Sr ratios are higher.Often the abundance of TI and the K/TI and TI/Sr ratios are more useful in delineating mineralized areas than the abundance of Rb and the K/Rb and Rb/Sr ratios. The ternary relationships between TI and several other elements, especially Rb, K, Ba, and Sr, show mineralized rocks to fall near the TI apices or near the TI-Rb or TI-K boundaries. 相似文献
16.
The Vestfold Block, like other Archaean cratons in East Antarctica and elsewhere, consists predominantly of felsic orthogneiss (Mossel and Crooked Lake gneisses), with subordinate mafic granulite (Tryne metavolcanics) and paragneiss (Chelnok supracrustals). Two major periods of continental crust formation are represented. The Mossel gneiss (metamorphosed about 3,000 Ma ago) is mainly of tonalitic composition, and is similar to much of the roughly coeval Napier Complex in Enderby Land. The Crooked Lake gneiss was emplaced under high-grade conditions about 2,450 Ma ago and comprises a high proportion of more potassic rocks (monzodioritic and monzonitic suites), as well as tonalite and minor gabbro and diorite. Both Mossel and Crooked Lake gneisses are depleted in Y and have moderate to high Sr, Ce/Y, and Ti/Y, consistent with melting of a mafic source (?subducted hydrated oceanic crust) leaving major residual hornblende (± garnet). Most Crooked Lake gneisses are more enriched in incompatible elements (P, Sr, La, Ce, and particularly Rb, Ba, and K) than Mossel gneisses, suggesting derivation from a more enriched mafic source. The Vestfold Block contains few orthogneisses derived by melting of older felsic crustal rocks, in marked contrast to the Archaean Napier Complex and, in particular, southern Prince Charles Mountains. Both Mossel and Crooked Lake tonalites are strongly depleted in Rb, K, Th, and U, and have very low Rb/Sr and high K/Rb; more potassic orthogneisses are depleted in Th, U, and, to lesser extents, Rb. Tryne metavolcanics are depleted in Th and Rb, but appear to have been enriched in K (and probably Na), possibly during early low-grade alteration. 相似文献
17.
大兴安岭富克山地区兴华渡口群地球化学及锆石U-Pb年龄特征 总被引：1，自引：0，他引：1
对富克山地区兴华渡口群岩石地球化学、锆石LA-ICP-MS U-Pb年代学研究结果表明,5件样品:Si O_2=50.24%~54.66%,Al_2O_3=14.41%~17.36%,Ca O=6.5%~8.68%,Na_2O=2.62%~4.67%,K_2O=1.36%~2.29%,Na_2O+K_2O=4.09%~6.3%,稀土总量∑REE=108.33×10~(-6)~240.28×10~(-6),稀土元素配分模式表现为轻稀土元素富集,重稀土元素相对亏损的右倾型曲线,具有弱的负铕异常。富集大离子亲石元素(K、Rb、Ba),相对亏损高场强元素(Nb、Ta、Zr、P、Ti等)。锆石U-Pb测年结果表明其岩浆形成时代为晚寒武世—早奥陶世(486.6±3.3 Ma)。富克山地区兴华渡口群原岩岩石组合类型为基性火山岩,为一套晚寒武世—早奥陶世活动大陆边缘火山建造。 相似文献
18.
对南堡凹陷馆陶组(粉)砂岩的主量、微量及稀土元素的地球化学特征研究表明：多数主量元素含量中等,SiO2、Al2O3等主元素含量及其相关比值反映大多数砂岩属于岩屑砂岩和长石砂岩,个别为杂砂岩;镁铁族元素(Co,Cr,Ni,Sc,V)和大离子亲石元素(Rb,Cs,Ba,Sr)含量类似于上地壳。砂岩十分相似的REE分布模式显示了相似的物源和构造背景。SiO2-K2O/Na2O图解、主元素双变量判别图解及Th-Sc-Zr/10和Th-Co-Zr/10等构造背景判别图解均表明,馆陶组物源区属于活动大陆边缘构造背景。根据主元素物源判别方程图、La/Sc-Co/Th和Th-Hf-Co图投影及(Gd/Yb)N值,表明馆陶组物源主要来自由长英质岩石组成的后太古宙上陆壳。通过与燕山地区不同时代(期)中酸性火山岩和花岗岩REE的对比,表明母岩主要来自燕山褶皱带地区于燕山期发育的中酸性火山岩和/或花岗岩体。 相似文献
19.
东昆仑可支塔格蛇绿混杂岩的地质地球化学特征 总被引：1，自引：0，他引：1
东昆仑可支塔格蛇绿混杂岩属于木孜塔格-鲸鱼湖大断裂的西延部分,主要由辉橄岩、辉长岩、闪长岩、斜长花岗岩、辉绿岩、玄武岩及硅质岩等组成,形成时代为早石炭世。为构造强烈破坏的蛇绿混杂岩,形成于俯冲带环境,属SSZ型蛇绿岩。其中辉橄岩以相对低SiO2、TiO2、Al2O3和CaO、高MgO为特征,贫有色金属成矿元素,富集相容元素Cr、Ni、Co。稀土总量低,接近于球粒陨石稀土元素总量,以LREE略富集为特征。闪长岩SiO2、K2O含量较低,MgO、CaO、Na2O较高,稀土总量高,∑REE为90.95μg/g,LREE富集。斜长花岗岩SiO269.8%,Na2O>K2O,K2O/Na2O为0.78,A/CNK为1.68,具有大洋斜长花岗岩的岩石化学特征。闪长岩、斜长花岗岩的微量元素特征相似,表现为大离子亲石元素K、Sr、Rb、Ba相对富集,高场强元素Nb、Ta、Zr、Hf相对亏损。研究表明,辉橄岩来源于亏损的地幔岩,接近于强烈亏损的方辉橄榄岩,而明显不同于结晶分异作用成因的超镁铁质岩石。闪长岩、斜长花岗岩为蛇绿混杂岩的浅色岩组分,是地幔岩浆结晶分异的产物。 相似文献
20.
This paper presents a study of Middle Paleozoic, Late Paleozoic, Early Cretaceous, and Early—Late Cretaceous granitoid complexes from two Pacific marginal seas. The granitoid complexes are subdivided into two large groups: (1) mantle-crust derivatives, including andesite differentiates, and (2) crustal palingenetic granites. In terms of formation depth, they are subdivided into abyssal, mesoabyssal, and hypabyssal granites, with decreasing depth from the old to young complexes. It was established that the granitoids of different genesis have peculiar geochemical features. The granitoids of distinguished genetic types differ in the content and proportions of alkalis, primarily, K, as well as Rb, Sr, and Ba. The palingenetic granites show the predominance of K over Na and are classified as high-K calc-alkaline rocks, whereas andesitic derivatives correspond to the calc-alkaline rocks. The former are characterized by the higher Rb and Ba contents, which is related to the geochemical affinity of these elements to K. In contrast, the Okhotsk Sea rocks are characterized by the predominance of Na over K, the elevated Sr content, and the lower Ba and Rb contents. In terms of geodynamic setting, the studied granitoids fall in the field of volcanic arcs and syncollisional rocks. The latters are represented by the palingenetic granitoids of the Sea of Japan. 相似文献