青藏高原北部发现印支运动的新证据——来自同构造花岗细晶岩脉的响应

在青藏高原北部昆仑山口-甘德断裂与巴颜喀拉山中央断裂之间发育延伸超过100 km的呈雁列排列的花岗细晶岩脉带,这些花岗细晶岩脉走向多为北西向(118°),少量呈南北向(2°)。通过对其宏、微观特征分析研究,并结合在这两组花岗细晶岩脉中分别采获的224.7±0.64 Ma(南北向)与220.5±1.1 Ma(北西向)的锆石LA-ICP-MS U-Pb同位素年龄数据,指出这些花岗细晶岩脉是印支运动的产物,是早印支期可可西里-巴颜喀拉地块向东昆仑地块斜向俯冲过程中,岩浆沿着昆仑山口-甘德北西向冲掩断层下盘(南盘)形成的北西向与南北向两组"X"型共轭剪节理贯入形成的同构造花岗细晶岩脉。两组"X"型共轭剪节理的展布方向揭示了印支运动的主压应力方向,即NNW-SSE向;北西向雁列排列的节理反映其受右行走滑作用控制的特点;花岗细晶岩脉形成的最早时间(224.7±0.64 Ma)代表了这次俯冲走滑事件的时间,也即昆仑山口-甘德断裂的形成时间。     

个旧老厂矿田花岗岩地球化学特征及其形成构造背景

个旧老厂矿田是中国著名的铜锡多金属矿产地而倍受关注,本文以个旧老厂矿田花岗岩体为研究对象,结合岩体产出的地质条件,在岩石学研究的基础上,运用主量元素及微量元素地球化学方法对老厂花岗岩的地球化学特征、源区及其形成的构造背景进行了系统研究。结果表明,老厂花岗岩体为一复式岩体,来源于陆壳岩石的部分熔融,但其具有不同的源区性质。构造环境判别图显示,老厂花岗岩体不同单元形成于不同的构造环境,与成矿作用有关的花岗岩则主要形成于后碰撞造山向板内环境的转换阶段,这种特殊的构造环境是区内超大型矿床形成的有利条件。     

The Turkei anorthosite complex revisited

Geological investigation in recent years reveals that the anorthosite-leuconorite massif (81 sq km) is much larger than known from previous studies. The massif is bordered by a suite of garnetiferous felsic rocks comprising quartz monzonite gneiss, granite gneiss and megacrystic K-feldspar-bearing granite. Ferrodiorites, hitherto unknown from this area, occur as veins at the massif-felsic suite interface, and as rare apophyses within leuconorites at the massif margin. The massif and the bordering felsic rocks were presumably emplaced during the earliest of the three phases of folding documented by the metasedimentary gneisses that host the massif. The petrographic and geochemical characteristics suggest that the low-K anorthosite-leuconoriteferrodiorite suite does not share a common parentage with the bordering high-K felsic intrusives. The anorthosites and leuconorites were derived by polybaric fractionation of mantle-derived melts. The ferrodiorites are anorthosite residual melts that were not entirely segregated from the host solids. By contrast, the granite gneisses and granites originated by incongruent melting of crustal rocks. The chemical differences between quartz monzonite and granite gneisses point to their derivation from different crustal precursors.     

A study of igneous rocks related to Zn–Pb mineralization in the Shinyemi and Gagok deposits of the Taebaeksan Basin,South Korea

The Shinyemi and Gagok deposits, located in the Taebaeksan Basin, South Korea, display Zn–Pb mineralization along a contact between Cretaceous granitoids and Cambrian–Ordovician carbonates of the Joseon Supergroup. The Shinyemi mine is one of the largest polymetallic skarn‐type magnetite deposits in South Korea and comprises Fe and Fe–Mo–Zn skarns, and Zn–Cu–Pb replacement deposits. Both deposits yield similar Cretaceous mineralization ages, and granitoids associated with the two deposits displaying similar mineral textures and compositions, are highly evolved, and were emplaced at a shallow depth. They are classified as calc‐alkaline, I‐type granites (magnetite series) and were formed in a volcanic arc. Compositional variation is less in the Shinyemi granites and aplites (e.g., SiO₂ = 74.4–76.6 wt% and 74.4–75.1 wt%, respectively) than in the Gagok granites and aplites (e.g., SiO₂ = 65.6–68.0 wt% and 74.9–76.5 wt%, respectively). Furthermore, SiO₂ vs K/Rb and SiO₂ vs Rb/Sr diagrams indicate that the Shinyemi granitoids are more evolved than the Gagok granitoids. Shinyemi granitoids had been already differentiated highly in deep depth and then intruded into shallow depth, so both granite and aplite show the highly evolved similar chemical compositions. Whereas, less differentiated Gagok granitoids were separated into two phases in the last stage at shallow depth, so granite and aplite show different compositions. The amounts of granites and aplite are similar in the Shinyemi deposit, whereas the aplite appears in an amount less than the granite in the Gagok deposit. For this reason, the Shinyemi granitoids caused not only Fe enrichment during formation of the dolomite‐hosted magnesian skarn but also was associated with Mo mineralization in the Shinyemi deposit. Zn mineralization of the Gagok deposit was mainly caused by granite rather than aplite. Our data suggest that the variation in mineralization displayed by the two deposits resulted from differences in the compositions of their associated igneous intrusions.     

Role of latitudinal compression in the formation of Paleozoic intrusive structures in the southern Primorye region in the Far East

The structural-geodynamic features of the Anna, Gaidamak, Dunai, Tinkan, and Tafuin gabbroid and granite intrusions are analyzed. They are recently considered as elements of the basite Sergeevka terrane, which was previously known as the Sergeevka metagabbroid inlier (or massif). At the same time, their outcrops mark the ENE-trending Tafuin anticlinorium, which, being conjugate and synchronous with the northerly adjacent Petrovka depression, was formed in the Mesozoic as a constituent of the long-living Sergeevka structure. Therefore, these intrusions are considered in this work along with Cretaceous massifs, which occur among Mesozoic sediments, as resulting from tectonic-magmatic pulses transforming the basic substrate. These pulses mark the Proterozoic-Early Paleozoic, Late Paleozoic, and Mesozoic geodynamic periods with each being characterized by particular directions of the lateral compression with the Late Paleozoic one being the most intense. The latter was responsible for the near-meridional elongation of the structures and the dominant directions of their elements: the layering, banding, taxitic textures, cleavage, and foliation. All of them were determined by the cleavage formation and thrusting (in form of counter thrusts) of the same direction. The intrusions exhibit shear-type pseudofolds, which are considered as produced by flattening and warping.     

川西李家沟锂多金属矿区晚三叠世花岗细晶岩脉的成因：地球化学、锆石U-Pb年龄和Hf同位素的证据

李家沟锂多金属矿床位于松潘–甘孜褶皱造山带东南缘,是近年来在区内发现的超大型锂多金属矿床,矿区内广泛发育花岗细晶岩脉。本文对花岗细晶岩脉进行了全岩地球化学测试、锆石U-Pb定年和Hf同位素分析,探讨其岩石成因及地质意义。花岗细晶岩锆石U-Pb加权平均年龄为200±2 Ma,属晚三叠世—早侏罗世。岩石具高硅（w（SiO₂）=73.27%~75.14%）、富铝（w（Al₂O₃）=14.8%~15.25%）、富碱（w（Na₂O+K₂O）=4.86%~8.08%）、贫钙（w（CaO）=0.45%~1.45%）的特征,A/CNK值均大于1.1,属中钾–高钾钙碱性强过铝质S型花岗岩。微量元素表现出Rb、Th、U、K的正异常和Ba、Sr、P、Ti相对负异常。稀土元素显示轻稀土富集、重稀土亏损及弱的负Eu异常（δEu=0.68~0.81）。岩石中锆石ε_Hf（t）值和对应的二阶模式年龄（t_DM2）较为均一,分别为－6.36～－3.39和1424～1616 Ma。研究表明,花岗细晶岩脉形成的构造背景为松潘–甘孜洋（古特提斯支洋）闭合后的后碰撞造山阶段,源岩为古老地壳变杂砂岩。结合前人研究成果,认为锂矿化花岗伟晶岩与花岗细晶岩为同一源区不同源岩（变泥质岩和变杂砂岩）部分熔融的产物。

     

Geologic structure of Western Primorye: Structuring dynamics

The first data are reported on the structuring dynamics of Western Primorye. The analysis of the structural parageneses of the least studied macro- and mesolevels of the arrangement of the geologic space allowed us to distinguish three sequentially superposed structural patterns (parageneses), each of which was formed by its own stress field during separate geodynamic periods: the Late Proterozoic-Early Paleozoic, the Middle-Late Paleozoic, and the Mesozoic-Cenozoic. During the first two episodes of geodynamic activation (Late Proterozoic-Early Paleozoic), the main compression axis was oriented longitudinally. The first episode was characterized by the formation of a thrust-fold structural pattern. The second episode resulted in the superposition of the meridional riftogenic structures and, respectively, in the pull-apart normal-fault segmentation of the crystalline basement into mainly longitudinal blocks, which partially coincide with the previously distinguished terranes. During the latitudinal compression and oblate deformation that predominanted during the Middle-Late Paleozoic geodynamic period, the down-thrown and uplifted blocks were transformed into depressions and arches, respectively. The depressions were filled with Paleozoic sediments, while the primary rocks in the arches experienced granitization with the formation of two granitic complexes that joined terranes. The granites are characterized by shadow and shear-type fold and pseudofolded forms. The Mesozoic-Cenozoic period governed by NNW compression is divided into the Triassic-Jurassic, Early Cretaceous, and Tertiary tectonic episodes. During the Triassic-Jurassic period, the ENE-trending narrow arches and depressions were formed by warping. The arches accumulated granitized rocks, while the depressions were compensated for by the Early-Late Triassic sedimentary-volcanogenic sediments. All these processes led to the formation of structural complexes that joined and overlapped older complexes of meridional blocks (terranes) across the strike. Two subsequent Mesozoic-Cenozoic episodes manifested themselves in the discrete formation of coal-bearing depressions due to the NNW compression and ENE extension of the warping products.     

海南抱伦矿区构造变形、成矿时代与金矿化关系研究

抱伦金矿床位于海南岛西南部乐东县境内,是一个以石英脉型为主的大型金矿床。野外地质调查表明,矿区大致经历了三期构造变形:早期(D1)NE向褶皱,中期(D2)NNW向褶皱和剪切变形,晚期(D3)脆性断层和节理。其中,中期的NNW向右行剪切变形为金矿体的赋存提供了主要空间,金矿化主要发生于三个不同的阶段,以第一阶段(自然金-Q2石英阶段)最为重要,形成了大量自然金,为主要矿化阶段。对切割矿体的细晶岩脉中锆石的定年研究表明,抱伦金矿化主要与印支期尖峰岭花岗岩浆活动有关,而与燕山晚期岩浆活动关系不大。     

The main reasons for the compositional evolution of the Early Paleozoic granitoids of the Eastern Sayan: Evidence from the Munku-Sardyk massif

This paper addresses the reasons for the evolution and genesis of the Early Paleozoic granitoids of the Munku-Sardyk Range, Eastern Sayan. It was established that the massif consists of three phases representing derivatives of mantle and crustal magmas. The major part of the massif is made up of mantle-derived granitoids, which are chemically similar to the exotic NEB-adakite association.The crustal granitoids of pluton were formed under the influence of the thermal field of primary magmas. The protoliths of these granitoids were presumably the metamorphic rocks of the Slyudyanka Group. In terms of geochemistry, they are ascribed to calc-alkaline rocks but bear some signatures of anorogenic granitoids.It was shown that the compositional variations of the granitoids were controlled by many factors, the most important of which are the compositions of primary magmas and their contaminant. The geochemical characteristics and mineral compositions of the granitoids distinctly reflect interaction with the host metamorphic sequences. Carbonate rocks played an important role in this process, causing an increase in the alkalinity and basicity of granitoid magmas. The abundance of carbonate rocks in the region was probably the main reason for the broad variations of alkalinity in coeval granitoids.Using the obtained data, a genetic model was proposed to explain all stages of the formation of the massif and compositional evolution of its rocks.     

小兴安岭霍吉河钼矿区含矿花岗岩类特征及成矿年龄

黑龙江霍吉河钼矿区内含矿花岗岩类岩石组合为黑云母二长花岗岩、二长花岗岩和花岗细晶岩,属高钾钙碱性岩-钾玄岩系列准铝质-过铝质岩石,具有轻稀土富集、重稀土亏损分馏模式;富集不相容元素(Cs、Th)并表现为Ta和Nb负异常以及Pb、Sr正异常,显示俯冲带地球化学特征.含矿岩浆岩明显富集Mo、Cu、Pb、Zn、W、Cr等金属元素.岩石全岩铅同位素来源比较复杂,具有混合成因铅特征.辉钼矿Re-Os模式年龄为180.7±2.5Ma和181.3±2.6Ma,钼矿成矿时代为早侏罗世.霍吉河钼矿是在蒙古-鄂霍茨克洋和古太平洋相向联合俯冲作用下,导致霍吉河地区发生地壳增生和壳幔相互作用以及后来的拆沉作用,形成了该区花岗质岩石和钼矿床.高度演化的花岗岩体(脉)可以作为今后本区钼矿床的找矿方向.     

Petrostructural evolution of ultramafic rocks of the Kalninsky chromite-bearing massif, Western Sayan

The Kalininsky ultramafic massif is a fragment of lower structural zone of the Kurtushiba ophiolitic belt in the extreme northeastern part of the Western Sayan. The massif is composed largely of rocks making up the dunite-garzburgite banded complex. The northeastern part of the massif is composed mainly of dunite with linear NW-trending chromite-bearing zones, the localization of which is controlled by banding of the dunite-harzburgite complex. Harzburgite and dunite are characterized by inhomogeneous structures and textures caused by nonuniform ductile deformation, which is expressed as heterogeneous extinction, kink bands, and syntectonic and annealing recrystallization. The petrostructural patterns of olivine in harzburgite and dunite provide evidence for three stages of ductile deformation. At the first stage under deep mantle-crustal conditions, the ductile flow of ultramafic rocks developed mainly in a regime of axial compression, high temperature (>1000°C), and low strain rate (? < 10^?6 s^?1), which resulted in translational gliding along the (010)[100] and (100)[001] systems in olivine and enstatite, respectively, in combination with a subordinate role of syntectonic recrystallization. Consequently, the rocks acquired a medium-grained (mesogranular) microstructure. At the second stage, related to the thermal effect on ultramafics, the ductile flow developed under the settings of low strain rate (? < 10^?6 s^?1) and rising temperature (>1000°C). The translational gliding in olivine proceeded largely along (010)[100] and was accompanied by diffusion creep. As the temperature rose, ductile deformation gave way to secondary recrystallization of annealing, which facilitated the growth of olivine grains free of dislocations owing to absorption of individual grains oriented adversely relative to the compression axis and deformed grains saturated with dislocations. As a result, dunite and harzburgite with a coarse-grained porphyroblastic microstructure have been formed. The third stage of ductile flow was apparently related to their transport along deep-seated thrust faults under settings of intense shear deformations at a high temperature (～1000°C) and strain rate (? >10^?4 s^?1). The ductile flow in olivine resulted in heterogeneous translational gliding along (010)[100] and accompanied by intense syntectonic recrystallization with the formation of a porphyroblastic microstructure. Chromite mineralization in dunite is controlled by internal banding. Intense ductile flow facilitated the metamorphic separation of linearbanded Cr-spinel segregations. Thus, the results of a petrostructural study show that ultramafic rocks of the Kalninsky massif, ascending to the upper lithosphere, underwent both axial and shear ductile deformations in the mantle and lower crust, and these deformations controlled chromite mineralization.     

广西栗木水溪庙不对称层状伟晶岩－细晶岩岩脉的成因讨论

水溪庙不对称层状伟晶岩─细晶岩岩脉生根于黄玉钠长石花岗岩中，其底板部分多以钠质细晶岩为主，顶板部分多以钾硅质伟晶岩为主，中间部分则往往以上述二种岩性的韵律式互层为主。笔者认为，岩脉的母岩浆应该与黄玉钠长石花岗岩的母岩浆相同，是一种富含Ｆ、Ｎａ的残余花岗质熔浆。岩脉自底板至顶板在组分和结构上的规律性变化，与这种特殊熔浆在岩脉环境下的分异演化、Ｆ含量的涨落和黄玉的周期性晶出以及熔浆结晶的动力学机制有关。     

基底收缩对斜向挤压盆地构造格局影响的实验研究

实验设计了不同基底条件的两个斜向挤压砂箱模型,实验结果表明:基底收缩可以促使斜向挤压盆地形成复杂的构造面貌,说明复杂构造格局并非总是意味着盆地经历了复杂的构造变形过程、或变形历史。基底收缩的斜向挤压实验模型说明盆地内部不同走向的断层也可以形成于同一挤压变形过程,不同走向的断层非总是意味着盆地经历了多期构造作用。基底收缩可以促使斜向挤压盆地形成雁列式断层带,雁列式断层带并非是走滑活动、或拉分作用的确凿证据。基底收缩可以促使斜向挤压盆地形成背冲式构造组合格局。基底收缩的斜向挤压实验模型为研究复杂构造格局盆地的成因机制提供了新思路。     

额尔古纳地块基底地质构造

额尔古纳地块是额尔古纳-马门-加格达奇拼合地块中的典型代表.研究表明,其基底由前中元古代绿岩及与之伴生的花岗质杂岩组成,它们具有地壳早期演化的地质构造特征.绿岩带为典型的变质基性-酸性火山岩及部分变质沉积岩系构成的火山-沉积建造,火山岩以拉斑玄武岩为主,向上过渡为钙碱性火山岩系列,表现为双峰态型特点.花岗岩类为TTG岩系及石英二长岩-花岗岩组合.花岗岩-绿岩地体内各岩石类型的岩石地球化学特征与国外太古宙及我国华北陆台花岗岩-绿岩带内同类岩石极为相似.双峰态型火山岩及绿岩建造组合,以及类似于TH2、FII型的变质基性火山岩和长英质火山岩特征,结合高铝型英云闪长岩-奥长花岗岩组合,指示了研究区绿岩带的形成环境类似于大陆边缘弧后裂谷型火山-沉积盆地.     

辽宁兴城新立屯地区岩浆杂岩岩石学特征、侵位顺序及地质意义

辽宁兴城新立屯地区岩浆杂岩主要由4种不同的岩石单元组成,分别为似斑状黑云母二长花岗岩,中细粒石英闪长岩,花岗细晶岩和花岗伟晶岩,前两者分布广泛且为研究区的主要岩石单元,后两者则呈脉状侵入到前两者中。应用LA-ICP-MS锆石U-Pb定年方法,测得似斑状黑云母二长花岗岩,中细粒石英闪长岩及花岗细晶岩的年龄分别为2 496±18 Ma,2 490±19 Ma,2 479±29 Ma,形成于古元古代早期。结合野外地质特征,侵位顺序由早到晚依次为:似斑状黑云母二长花岗岩,中细粒石英闪长岩,花岗细晶岩,花岗伟晶岩。岩石地球化学特征显示,新立屯地区岩浆杂岩主量元素方面具高硅(SiO2=61.38%~74.99%),富碱(Na2O+K2O=6.86%~9.41%),富Mg#(56~70)特征;A/CNK=0.91~1.18,属准铝质-过铝质岩石;微量元素方面,相对富集轻稀土元素,亏损重稀土元素,具有Eu异常(δEu=0.50~0.96);富集大离子亲石元素,亏损高场强元素;锆石Lu-Hf同位素特征εHf(t)值为-1.12~+6.13;TDM2(Hf)介于2 594~2 937 Ma,显示该套岩浆杂岩可能为地幔物质加入新生地壳再造的产物。     

Age and sources of the Paleoproterozoic premetamorphic granitoids of the Goloustnaya block of the Siberian craton: Geodynamic applications

This paper reports the results of geological, geochronological, and isotope geochemical investigations of two premetamorphic granite massifs of the Goloustnaya block of the Baikal salient of the basement of the Siberian craton and granite gneisses from the migmatite–gneiss sequence of this block. The U–Pb zircon age of the granites of the Khomut massif is 2153 ± 11 Ma. The age of the Elovka massif was previously determined by us as 2018 ± 28 Ma. The Khomut and Elovka granites underwent structural and metamorphic transformations accompanied by migmatization. An age of 1.98–1.97 Ga was obtained for the structural and metamorphic processes in the Goloustnaya block from the analysis of margins of zircon grains from the Khomut granites and zircon from the granite gneisses. The biotite granites of the Khomut massif show transitional I–S-type geochemical characteristics, which allowed us to suggest that they were derived by melting of a crustal source of intermediate–acid composition. The Khomut granites show positive ε_Nd(T) values from +2.0 to +2.2 and a Nd model age of 2.4 Ga, which may indicate their formation owing to the reworking of the Paleoproterozoic juvenile continental crust. The combined isotope geochemical data are consistent with collision of island arcs as a possible environment for the formation of the Khomut granites. The formation of these granites was not related to the development of the structure of the Siberian craton, similar to a few other anorogenic magmatic complexes of the margin of the Chara–Olekma terrane of the Aldan shield with ages of ~2.2–2.1 Ga, including the granites of the Katugin complex. The biotite–amphibole granites of the Elovka massif with an age of ~2.02 Ga are geochemically similar to I-type granites. The geochemical characteristics of these granites, including elevated Sr and Ba and low Nb and Ta contents, were inherited from a subduction-related source. Negative ε_Nd(T) values from–0.9 to–1.8 and rather high contents of K₂O and Th allow us to suppose a metamagmatic crustal source for the granites of the Elovka massif. The combined isotope geochemical characteristics of the Elovka granites suggest that a mature island arc or an active continental margin is the most probable environment of their formation. The estimates of the age of structural and metamorphic processes affecting the Goloustnaya block (1.98–1.97 Ga) coinciding with the time of similar transformations in the central part of the Aldan shield and eastern Anabar shield (1.99–1.96 Ga) indicate wide occurrence of collisional events of similar age in the Siberian craton and allow us to consider this age interval as an early large-scale stage of the formaiton of the structure of the Siberian craton.     

The origin of banding in the Main Donegal Granite,N.W. Ireland

This Caledonian pluton exhibits a regular, sub-vertical banding in which layers of dark, relatively fine grained trondhjemite alternate with layers of light, coarse grained granite. The textures and the presence of cross-cutting bands of granite indicate that the light bands were derived by potash feldspathization of the trondhjemite. The geometry of the banding indicates that it formed during the “synplutonic” deformation of the pluton, largely in situ. The bands formed by segregation of alkalies into dilatant zones of movement produced during the deformation of partly consolidated magma.     

Synkinematic granitoid magmatism of Western Sangilen,South-East Tuva

The problems of tectonic control of composition, size, and morphology of synkinematic crustal granitoids are discussed by the example of the Western Sangilen granites (South-East Tuva). Comparative analysis was performed for felsic bodies and massifs spatially confined to tectonic zone (Erzin shear zone): Erzin migmatite–granite complex (510–490 Ma), Matut granitoid massif (510–490 Ma), Bayankol polyphase gabbro-monzodiorite–granodiorite–granite massif (490–480 Ma), and the Nizhneulor Massif (480–470 Ma). It is shown that synkinematic felsic melts during the transition from collisional compression to transpression were formed at different crustal levels. An increase of shear component provided favorable conditions for the migration of felsic melts, increase of size and morphology of intrusive bodies from vein type to harploith (likely, loppoliths and laccoliths) and further to stocks. All kinematic granitoids of the Erzin tectonic zone are ascribed to the crustal S-type granites. Dispersion and average chemical composition of the synkinematic granites strongly depend on the degree of their “isolation” from protolith. From auto- and paraautochthonous granitoids to allochthonous granites, the compositional dispersion decreases and the chemical composition is displaced toward I-type magmatic rocks.     

佳木斯地块北部早古生代沉积建造的时代与物源:来自岩浆和碎屑锆石U-Pb年龄及Hf同位素的制约

本文对出露于佳木斯地块北部金银库组变沉积岩和侵入其中的火成岩脉体中的锆石进行了系统的LA-ICP-MS/SIMS U-Pb定年和Hf同位素研究,旨在限定金银库组的沉积时限,并揭示其物源及沉积环境。3个样品中锆石呈自形-半自形,显示典型的岩浆生长环带或条痕状吸收,暗示其岩浆成因。研究结果显示:采自金银库组绢云母片岩中的碎屑锆石72个分析点给出1 955~457 Ma的年龄区间,主要峰期年龄为814、757、568、491和463 Ma,其ε_Hf（t）值为-13.9~-0.1,Hf同位素一阶段模式年龄T_DM1和二阶段模式年龄T_DM2分别为1 827~1 307 Ma和2 411~1 715 Ma。采自侵入金银库组的花岗细晶岩和辉绿岩分别给出了263和267 Ma的结晶年龄,前者的ε_Hf（t）值为0.9~2.0,Hf同位素二阶段模式年龄T_DM2为1 110~1 047 Ma;后者的ε_Hf（t）值为-7.7~6.4,Hf同位素一阶段模式年龄T_DM1为1 206~662 Ma。结合佳木斯地块及邻区约430 Ma火成岩的存在和金银库组中该期碎屑锆石的缺乏以及碎屑锆石年龄众数及其Hf同位素组成,我们认为金银库组的形成时代应为晚奥陶世至早志留世（463~430 Ma）,形成于被动大陆边缘背景,沉积物源主要来自佳木斯地块及其邻区的古元古代和早古生代早期火成岩。