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1.
Yo-ichiro Otofuji Takaaki Matsuda Ryo Enami Koji Uno Katsuhiko Nishihama Li Su Ruslan G. Kulinich Petr S. Zimin Anatoly P. Matunin Vladimir G. Sakhno 《Tectonophysics》2002,350(3)
We present paleomagnetic results of Paleocene welded tuffs of the 53–50 Ma Bogopol Group from the northern region (46°N, 137°E) of the Sikhote Alin volcanic belt. Characteristic paleomagnetic directions with high unblocking temperature components above 560 °C were isolated from all the sites. A tilt-corrected mean paleomagnetic direction from the northern region is D=345.8°, I=49.9°, α95=14.6° (N=9). The reliability of the magnetization is ascertained through the presence of normal and reversed polarities. The mean paleomagnetic direction from the northern region of the Sikhote Alin volcanic belt reflects a counterclockwise rotation of 29° from the Paleocene mean paleomagnetic direction expected from its southern region. The counterclockwise rotation of 25° is suggested from the paleomagnetic data of the Kisin Group that underlies the Bogopol Group. These results establish that internal tectonic deformation occurred within the Sikhote Alin volcanic belt over the past 50 Ma. The northern region from 44.6° to 46.0°N in the Sikhote Alin volcanic belt was subjected to counterclockwise rotational motion through 29±17° with respect to the southern region. The tectonic rotation of the northern region is ascribable to relative motion between the Zhuravlevka terrane and the Olginsk–Taukhinsk terranes that compose the basements of the Sikhote Alin volcanic belt. 相似文献
2.
Kohei SATO Anatoly A. VRUBLEVSKY Sergei M. RODIONOV Nikolai P. ROMANOVSKY Munetomo NEDACHI 《Resource Geology》2002,52(1):1-14
Abstract: Age of magmatism and tin mineralization in the Khingan‐Okhotsk volcano–plutonic belt, including the Khingan, Badzhal and Komsomolsk tin fields, were reviewed in terms of tectonic history of the continental margin of East Asia. This belt consists mainly of felsic volcanic rocks and granitoids of the reduced type, being free of remarkable geomagnetic anomaly, in contrast with the northern Sikhote‐Alin volcano–plutonic belt dominated by oxidized‐type rocks and gold mineralization. The northern end of the Khingan‐Okhotsk belt near the Sea of Okhotsk, accompanied by positive geomagnetic anomalies, may have been overprinted by magmatism of the Sikhote‐Alin belt. Tin–associated magmatism in the Khingan‐Okhotsk belt extending over 400 km occurred episodically in a short period (9510 Ma) in the middle Cretaceous time, which is coeval with the accretion of the Kiselevka‐Manoma complex, the youngest accretionary wedge in the eastern margin of the Khingan‐Okhotsk accretionary terranes. The episodic magmatism is in contrast with the Cretaceous‐Paleogene long–lasted magmatism in Sikhote–Alin, indicating the two belts are essentially different arcs, rather than juxtaposed arcs derived from a single arc. The tin‐associated magmatism may have been caused by the subduction of a young and hot back‐arc basin, which is inferred from oceanic plate stratigraphy of the coeval accre‐tionary complex and its heavy mineral assemblage of immature volcanic arc provenance. The subduction of the young basin may have resulted in dominance of the reduced‐type felsic magmas due to incorporation of carbonaceous sediments within the accretionary complex near the trench. Subsequently, the back‐arc basin may have been closed by the oblique collision of the accretionary terranes in Sikhote–Alin, which was subjected to the Late Cretaceous to Paleogene magmatism related to another younger subduction system. These processes could have proceeded under transpressional tectonic regime due to oblique subduction of the paleo‐Pacific plates under Eurasian continent. 相似文献
3.
The chemical and trace-element features of the Late Cretaceous and Early Paleogene ignimbrite complexes of East Sikhote Alin are discussed. The Turonian-Campanian volcanic rocks of the Primorsky Complex compose linear structure of the Eastern Sikhote Alin volcanic belt. They are represented by crystalrich rhyolitic, rhyodacitic, and dacitic S-type plateau ignimbrites produced by fissure eruptions of acid magmas. The Maastrichtian-Paleocene volcanic rocks occur as isolated volcanic depression and caldera structures, which have no structural and spatial relations with the volcanic belt. This period is characterized by bimodal volcanism. The Samarginsky, Dorofeevsky, and Severyansky volcanic complexes are made up of basalt-andesite-dacite lavas and pyroclastic rocks, while the Levosobolevsky and Siyanovsky complexes are comprised of rhyolitic and dacitic tuffs and ignimbrites. Petrogeochemically, the felsic volcanic rocks are close to the S-type plateau ignimbrites of the Primorsky Complex. The Paleocene-Early Eocene silicic volcanics of the Bogopolsky Complex are represented by S- and A-type dacitic and rhyolitic tuffs and ignimbrites filling collapsed calderas. The eruption of A-type ferroan hyaloignimbrites occurred at the final stage of the Paleogene volcanism (Bogopolsky Complex). The magmatic rocks show well expressed mineralogical and geochemical evidence for the interaction between the crustal magmas and enriched sublithospheric mantle. It was shown that the revealed differences in the mineralogical and geochemical composition of the ignimbrite complexes are indicative of a change in the geodynamic regime of the Asian active continental margin at the Mesozoic-Cenozoic transition. 相似文献
4.
New data are presented on the geology and composition of volcanic and intrusive rocks of the Orochenka caldera, which is located in the western part of the East Sikhote Alin volcanic belt. The SHRIMP and ICP MS age of zircons of volcanic and intrusive rocks, respectively, and the composition of the volcanic rocks allow comparison of these complexes with volcanic rocks of the eastern part of the volcanic structure. New data indicate the period of transition between subduction to transform regimes. 相似文献
5.
Abstract: Sn, B and Pb-Zn skarn, vein and disseminated deposits occur in the eastern part of Sikhote-Alin fold system associated with the late Cretaceous-earliest Paleogene volcano-plutonic complexes, which are products of a continental margin-type subduction along the East Sikhote-Alin belt. There are two metallogenic zones where the ore deposits are concentrated. The Taukha metallogenic zone combining B and Pb-Zn skarn, vein and disseminated deposits occurs on the main volcanic chain along the Japan Sea coast. Late Cretaceous-earliest Paleogene calc-alkaline plutonic and volcanic rocks of magnetite series predominate here. Volcanic rocks overlie on the lower Cretaceous Taukha terrane which consists of abundant olistostromes with numerous olistoliths of Triassic limestones. During the middle-late Cretaceous time, an ignimbrite erupted and formed a huge borosilicate skarn deposit. A later subduction related volcanism of the late Cretaceous-earliest Paleogene stage (70–55 Ma) was predominated by andesites and rhyodacites. Many Pb-Zn skarn and vein deposits were formed. Sulfur isotope compositions of galena in the B and Pb-Zn deposits of the Taukha metallogenic zone vary from –1. 3 to +2. 0%, averaging 0% in the δ34 S. 相似文献
6.
Based on geological and isotope geochemical data obtained during the past decade, the eastern Sikhote Alin volcanic belt can be considered as a polygenic structure with spatially superimposed magmatic complexes of different geodynamic stages. Only Late Cretaceous intermediate and silicic volcanics enriched in LILE and depleted in HFSE can be interpreted as typical subduction complexes. Cenozoic lavas of mainly basic composition were formed after the termination of active subduction under complex dynamic conditions of the rearrangement of eastern Eurasia owing to the collision with the Indian plate. The eruption of Eocene-Oligocene-early Miocene basalts corresponded to the transform continental margin environment, rupture of an ancient subducted slab, and upwelling of hot depleted oceanic asthenosphere of the Pacific MORB-type into the Asian subcontinental lithosphere with EMII-like isotopic characteristics. The late Miocene-Pliocene magmatic activity of the eastern Sikhote Alin showed an intraplate character, but the composition of erupted magmas was strongly affected by previous tectonomagmatic events: subduction of different ages and opening of the Sea of Japan Basin. The distinct EMI isotopic signature of low-potassium plateau basalts, which is not observed in the lavas of earlier stages of volcanic belt evolution, suggests that the continental asthenosphere contributed to magma formation, and the direction of mantle flows changed owing to the formation of a new subduction zone. 相似文献
7.
8.
Abstract: Systematic measurements of magnetic susceptibility were carried out at the outcrops of the Uchiyama granitic pluton, Tsushima Islands. The pluton consists of hornblende-biotite granodiorite and biotite granite. It intrudes concordantly along an anticline axis of the Taishu Group in middle Miocene (16. 10. 5 Ma), and crops out in five areas. The results show that the low magnetic susceptibility facies (LM–facies, <100A-10-6 emu/g) always occurs in the peripheral part of the pluton, while the high magnetic susceptibility facies (HM–facies, > 250 A 10-6 emu/g) occupies the core through the medium magnetic susceptibility zone (MM–facies). It is pointed out that the pluton forms a magnetic zoning within a single plutonic body.
Chemical compositions of the granitoids show no conspicuous differences in major elements among the LM–, MM–, and HM–facies. Biotites from the LM–, MM–, and HM-facies also indicate uniform compositions with Fe/(Fe+Mg)=0. 6.
The pluton is principally surrounded by black mudstones of the Lower Formation of the Taishu Group, which is deltaic to shallow sea sediments of the Eocene to early Miocene age, and the carbon contents in them were analyzed. The analyses show that carbon was mostly decomposed and lost in the hornfels zone, while mudstones in the non-hornfels zone usually contain 0. 5 to 0. 7 % C.
From these facts, it is concluded that the magnetically zoned pluton at Tsushima was formed by an external volatile buffer system such as CH4 –CO2 during the solidifying magma process. 相似文献
Chemical compositions of the granitoids show no conspicuous differences in major elements among the LM–, MM–, and HM–facies. Biotites from the LM–, MM–, and HM-facies also indicate uniform compositions with Fe/(Fe+Mg)=0. 6.
The pluton is principally surrounded by black mudstones of the Lower Formation of the Taishu Group, which is deltaic to shallow sea sediments of the Eocene to early Miocene age, and the carbon contents in them were analyzed. The analyses show that carbon was mostly decomposed and lost in the hornfels zone, while mudstones in the non-hornfels zone usually contain 0. 5 to 0. 7 % C.
From these facts, it is concluded that the magnetically zoned pluton at Tsushima was formed by an external volatile buffer system such as CH
9.
A. V. Kudymov 《Russian Journal of Pacific Geology》2013,7(4):277-287
By the stress field’s reconstruction and the analysis of the distribution for the slickenside belts and the dike-hosting faults, the dominating left-lateral strike slip component is found for the Kolumbe Fault. This component is caused by the regional SES-NWN compression. The igneous rocks of the East Sikhote Alin volcanic-plutonic belt are considered as units synchronous with the regional displacement. Following the opinion of V.P. Utkin, the rift strike-slip-tension origin of these structures is suggested. Based on the structural-tectonic position of the volcanic rocks and the accompanying intrusive bodies and on the other geological data as well, several dislocation stages are distinguished in the Kolumbe Fault’s evolution. It is found that the dominating strike-slip motions along the main fault and its feathering faults changed to normal and reverse faulting deformations at the end of every stage. 相似文献
10.
G. A. Valui E. Yu. Moskalenko A. A. Strizhkova G. R. Sayadyan 《Russian Journal of Pacific Geology》2008,2(2):150-157
The Cretaceous-Paleogene granites of the Eastern Sikhote Alin volcanic belt (ESAVB) and Late Cretaceous granitoids of the Tatibin Series (Central Sikhote Alin) are subdivided into three groups according to their oxygen isotope composition: group I with δ18O from +5.5 to +6.5‰, group II with δ18O from +7.6 to +10.2‰, and group III with less than +4.5‰. Group I rocks are similar in oxygen isotope composition to that of oceanic basalts and can be derived by melting of basaltic crust. Group II (rocks of the Tatibin Series) have higher δ18O, which suggests that their parental melts were contaminated by sedimentary material. The low 18O composition of group III rocks can be explained by their derivation from 18O-depleted rocks or by subsolidus isotopic exchange with low-18O fluid or meteoric waters. The relatively low δ18O and 87Sr/86Sr in the granitoids of Primorye suggest their derivation from rocks with a short-lived crustal history and can result from the following: (1) melting of sedimentary rocks enriched in young volcanic material that was accumulated in the trench along the transform continental margin (granites of the Tatibin Series) and (2) melting of a mixture of abyssal sediments, ocean floor basalts, and upper mantle in the lithospheric plate that subsided beneath the continent in the subduction zone (granites of the ESAVB). 相似文献
11.
《International Geology Review》2012,54(11):1994-2016
There is no clean-cut boundary within the upper crust between volcanic and plutonic phenomena, nor between their associations. Numerous examples from the comparatively young circum-Pacific belt — and a number from older associations throughout the world — are presented to illustrate this point of view. Most of the examples are of volcanoes with deeply eroded cores consisting of crystallized porphyritic to even-grained rocks, or of "batholiths" capped by genetically related effusive and pyroclastic rocks, especially ignimbrites. The ever-growing roster of such examples indicates that they are the rule rather than the exception. Modern systematics of igneous rocks should have three, rather than two, main divisions: volcanic, plutonic, and volcano-plutonic. These three rock types reflect the overall progress of igneous activity within the diversity of natural processes. Only by conceding the presence of companion volcanic phenomena for shallow to intermediate plutonic phenomena, and vice versa, can one gain an understanding of magmatic phenomena actually existing under certain geologic conditions. The controlling tectonic mechanism for alternation of comagmatic volcanic and plutonic series remains obscure. Tectono-physical analysis of such associations must be supported by field data. Eventually, it should be possible to set up a general structural and genetic systematics of igneous rocks and to work out a classification of volcano-plutonic rocks now underway. — R. C. Epis. 相似文献
12.
The Milogradovo gold-silver deposit, which is of the intracaldera structural type, was formed within the ore-magmatogenic
system (OMS), which combines a set of genetically and paragenetically related subvolcanic complexes, cover volcanogenic units,
diatremes, hydrothermal rocks, and ore zones of variable mineral associations. The deposit is located within the Limovskaya
caldera. The first U-Pb dating of zircons from the caldera’s igneous rocks using the SHRIMP method has shown that these are
related to the Eocene stage of magmatism (the Milogradovo volcanic-extrusive complex). Such types of volcanic structures are
widespread in the East Sikhote Alin Belt and are the most promising in the sense of Au-Ag mineralization. 相似文献
13.
中亚造山带西南缘东天山觉罗塔格造山带广泛发育石炭纪火山岩,这些石炭纪火山岩的成因和构造历史一直是该区域地质问题争论的焦点.通过对东天山觉罗塔格造山带石炭纪基性火山岩详细的岩石学、地球化学、锆石U-Pb年代学和Sr-Nd同位素研究,获得了如下认识:（1）东天山觉罗塔格造山带石炭纪基性火山岩分为两期爆发,早期爆发时间为336 Ma,晚期爆发时间为320 Ma.早期336 Ma基性火山岩由玄武岩、玄武安山岩及同成分的火山碎屑岩组成,显示出弧火山岩属性;晚期320 Ma基性火山岩主要由玄武岩和玄武安山岩组成,包括Ⅰ型火山岩和Ⅱ型火山岩,Ⅰ型显示出大洋中脊玄武岩属性,Ⅱ型显示出弧玄武岩特征.（2）石炭纪基性火山岩中发现的大量捕获锆石（371~3 106 Ma）年龄谱系与中天山地块显示为相似的特征,表明它们在石炭纪之前可能同属一个板块,也指示早古生代地壳可能参与了成岩过程.（3）该区域石炭纪火山岩与现今存在的Okinawa Trough和Mariana Trough弧后盆地玄武岩（BABB）很相似,从弧玄武岩向洋中脊玄武岩的演变,反映了石炭纪中天山北部弧后盆地的发展.因此推断早石炭世火山岩为弧后盆地初始裂开阶段的产物,而晚石炭世火山岩为弧后盆地弧后扩张阶段的产物.早石炭世晚期的初始裂开和晚石炭世早期的弧后扩张表明天山洋的俯冲最终结束于晚石炭世末期,包括主大洋和弧后盆地最终关闭,而最终关闭的位置很可能位于中天山以南. 相似文献
14.
I. P. Voinova 《Russian Journal of Pacific Geology》2016,10(3):230-238
The results of study of the volcanic rocks of the Khabarovsk accretionary complex, a fragment of the Jurassic accretionary prism of the Sikhote Alin orogenic belt (the southern part of the Russian Far East), are presented. The volcanic rocks are associated with the Lower Permian limestones in the mélange blocks and Triassic layered cherts. The petrography, petrochemistry, and geochemistry of the rocks are characterized and their geodynamic formation conditions are deduced. The volcanic rocks include oceanic plume basalts of two types: (i) OIB-like intraplate basalts formed on the oceanic islands and guyots in the Permian and Triassic and (ii) T(transitional)-MORBs (the least enriched basalts of the E-MORB type) formed on the midoceanic ridge in the Permian. In addition to basalts, the mélange hosts suprasubduction dacitic tuff lavas. 相似文献
15.
新疆东准噶尔石炭纪火山机构类型与时限 总被引：10，自引：2，他引：8
东准噶尔卡拉麦里大气田的主要储层是石炭纪火山岩,石炭纪古火山机构的样式与组合特征,与火山岩储层展布关系密切。野外调查表明,隐爆角砾岩是东准噶尔石炭纪古火山机构最常见的标志之一。东准噶尔石炭纪古火山机构类型主要有中心式、裂隙式和裂隙-中心式等样式。中心式火山机构以大石头层状火山、柯克巴斯套锥状火山最为典型;巴塔玛依内山附近沿断裂分布的带状火山岩具有裂隙式喷发的特征;东黑山火山具有火山口串珠状排列特征,是裂隙-中心式喷发的产物。大石头地区原缪林托凯陶山组火山岩的锆石SHRIMP U-Pb年龄为345.6±7.1 Ma,而已知巴塔玛依内山组火山岩年龄是350.0±6.3Ma,因此东准噶尔火山活动的主要时期是早石炭世。 相似文献
16.
西藏冈底斯带中部南木林地区林子宗群火山岩锆石U-Pb年龄和地球化学特征 总被引：1，自引：0，他引：1
林子宗群火山岩广泛分布在冈底斯带上,其岩石学特征及所代表的区域不整合事件被认为与特提斯洋俯冲消减到印度-亚洲大陆碰撞转变有关。对冈底斯带南木林地区的林子宗群火山岩进行了LA-ICP-MS锆石U-Pb测年及地球化学研究,获得林子宗群火山岩帕那组LA-ICP-MS锆石U-Pb年龄为46.08±0.47Ma、49.00±1.30Ma,对比冈底斯带其他地区已发表的年龄数据,认为印度-亚洲大陆碰撞(在西藏南部)的时间,东部可能依次早于中部和西部。地球化学特征表明,冈底斯带南木林地区林子宗群火山岩具有碰撞后地壳加厚背景下产生的弧火山岩特征,应为新特提斯洋俯冲消减到印度-亚洲大陆碰撞构造背景下形成的。 相似文献
17.
A classification diagram was empirically developed for acid volcanic rocks formed in modern geodynamic settings and reflects their peculiar chemical features. The testing of the binary diagram Al2O3/(CaO + MgO)?Fe2O 3 Tot /(CaO + MgO) for the Late Cretaceous (Pimorsky, Siyanovsky, Kamensky, and Levosobolevsky) and Paleogene (Bogopolsky) Volcanic Complexes of East Sikhote Alin demonstrated its high efficiency for deciphering the tectonic settings of ancient acid volcanism. 相似文献
18.
I. Yu. Chekryzhov V. K. Popov A. N. Panichev V. V. Seredin E. V. Smirnova 《Russian Journal of Pacific Geology》2010,4(4):314-330
This paper presents the results of studying the Cenozoic volcanogenic-sedimentary cover of the Vanchinskaya depression of
Sikhote Alin. It was established that, in terms of the taxonomic composition of the fossil plants, the basal part of the Cenozoic
section is attributed to the Paleocene, while the overlaying coal-bearing sequence, to the Early Eocene. The geochronological
(K-Ar) dating showed that the volcanic rocks intruding and overlaying the coal-bearing deposits are Middle Eocene in age:
rhyolites—44.7 ± 1.0; trachyandesites—43.7 ± 1.4 Ma. The petrographic and geochemical characteristics of the volcanic and
volcanogenic-sedimentary rocks and related zeolitites are described. The zeolitized rocks containing plant detritus differ
in their extremely high contents of Y and HREE. The zeolitization of the volcanic glass in tuffs, tuffites, and perlites was
caused by hydrothermal solutions that ascended along NW fault zones from the subsurface magmatic chamber. 相似文献
19.
西藏冈底斯西段狮多地区火山岩的地质地球化学特征 总被引：1，自引：4，他引：1
西藏冈底斯西段狮多地区火山岩为一套高钾钙碱性和钙碱性系列岩石,分为古新世(59 7Ma)和中新世(17 2Ma)两个活动时期,早期的时代和层位大致相当于冈底斯东段的林子宗群典中组。与典中组火山岩相比较,该期火山岩的稀土元素总量(w(∑REE)=58 83×10-6)低得多,轻、重稀土分馏程度(w(La)N/w(Yb)N=3 44)较弱,分布曲线更为平缓;N(143Nd)/N(144Nd)的现在值(0 512275～0 512420)和初始值εNd(t)(-6 7～-4 0)也明显偏低,这反映冈底斯东、西段同一时期的火山活动及演化各具特色。根据Pb、Nd、Sr同位素的组成特征和微量元素构造环境判别推断,狮多地区火山岩形成于陆缘弧—陆 陆碰撞造山的发展演化环境,是新特提斯洋壳向大陆下俯冲作用过渡到陆 陆碰撞造山作用的产物。狮多铁 铜矿与古新世火山岩有成因联系。 相似文献
20.
HETEROGENEITY OF THE LITHOSPHERE IN TIBETAN PLATEAU ON THE CONSTRAINTS OF MAGMATISM 相似文献