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1.
地幔柱构造对松辽盆地及渤海湾盆地形成的制约 总被引：16，自引：0，他引：16
中国东部松辽盆地和渤海湾盆地形成与演化的深部动力学机制尚未得到很好的解释．通过对区域地震资料盆地沉积记录、火山岩岩石探针和大地构造演化历史的综合分析,认为地幔柱(柱头直径约500km)在晚侏罗世一晚白垩世时形成于松辽地区,经历了软流圈地幔上涌、地壳抬升与伸展、火山活动,导致松辽盆地的形成;由于华北板块向北移动,始新世时地幔柱(柱头直径600-800km)移动到京津一渤海湾地区,类似的地质过程形成了渤海湾盆地．渤海湾地幔柱的活动还可能是京津唐地区地震多发的根本原因。 相似文献
2.
《Russian Geology and Geophysics》2016,57(5):790-808
We provide new isotope-geochronological evidence for the synchronous occurrence of Late Paleozoic basic and granitoid magmatism in western Transbaikalia; this is a strong argument for the contribution of mantle magmas to granitoid petrogenesis. The Late Paleozoic basic rocks originated from the phlogopite-garnet-bearing lherzolitic mantle, which melted under “hydration conditions.” The specific features of Late Paleozoic magmatism in western Transbaikalia were determined by the combination of the activity of a low-energy mantle plume with the final stage of the Hercynian orogeny in space and time. At the early stage of magmatism, during the formation of the Barguzin granites,the plume had only a thermal influence on the crustal rocks heated as a result of Hercynian fold-thrust deformations. The mixing of mantle basic and crustal salic magmas at different levels marked the transition from crustal to mixed (mantle-crustal) granites, which include all post-Barguzin complexes (probably, except for alkali granites). In the geologic evolution of Transbaikalia, the Late Paleozoic magmatism was postorogenic, but it was initiated and influenced by the mantle plume. 相似文献
3.
华北古陆的形成与构造演化史 总被引：1，自引：0，他引：1
以华北古陆为例，论述了地球演化史中经历的三大阶段：（１）古陆的形成阶段（４６００～１８００Ｍａ）：地球形成早期，以地幔对流为主导作用，到早太古宙出现初始古陆核，地幔对流驱动的地体拼贴和板底垫托是陆壳形成的主要方式；中太古宙开始出现一定规模的坳陷盆地，发育了基性火山岩 碎屑岩 镁质碳酸盐岩等表壳岩，同时伴随着大量中基性、花岗质岩浆活动；晚太古宙和早元古宙是陆壳形成的主要时期，并已具现今板块活动特征。地幔热柱与板块构造共同控制着地壳运动。（２）古陆稳定发展阶段（１８００～２５０Ｍａ）：地幔热柱活动较弱，古陆主要表现为缓慢的升降运动（造陆运动）。（３）地球新活动时期（２５０Ｍａ至今）：地幔热柱活动进入一个新的活跃时期。岩石圈发生明显的热减薄，地幔热柱表现为多级演化，并导致盆岭系的形成。 相似文献
4.
峨眉地幔柱的动力学特征 总被引：46，自引：1，他引：46
峨眉地幔柱起源于赤道附近,头部直径约８００ｋｍ。它的动力学特征主要反映在四大地质事件上：１．基性岩浆活动,地幔柱头部减压熔融引起大规模玄武岩浆喷发和大量基性－超基性岩体侵入。峨眉山玄武岩分布面积约５０万ｋｍ２,主喷发期在早、晚二叠世之间,活动时限海西晚期－印支期;２．酸性岩浆活动,地幔柱对深部地壳的热改造引起大规模酸性岩浆喷发并形成３００ｋｍ长的花岗岩带,酸性火山喷发产物除流纹岩外,酸性火山灰沉积遍及整个华南地区;３．古地热场与改造成矿作用,在地幔柱作用下,上扬子及其外围地区曾经存在一个古地热场,地热异常从海西晚期持续到燕山期,长时期的地热异常驱动热水循环,引起大规模改造成矿作用,形成分布广泛的层控金属矿床;４．地壳升降与裂陷,华南海西－印支期的地壳运动与地幔柱有密切关系,当它到达岩石圈底部之后,上覆岩石圈受热软化,伸展变薄,地壳沉降引起栖霞期海平面大幅度上升以及茅口期的强烈拉张与裂陷,地幔柱活动对大气圈、水圈、生物圈都有重要影响,它可能造成大规模生物绝灭。 相似文献
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A.P. Berzina V.O. Gimon I.V. Nikolaeva S.V. Palesskii A.V. Travin 《Russian Geology and Geophysics》2009,50(10):827-841
The Erdenetiyn-Ovoo magmatic center (EMC) with a porphyry Cu-Mo deposit includes the following intrusive complexes: Selenga, Shivota, ore-bearing porphyry, and post-ore dike. The EMC formed at 260–200 Ma. The geologic evolution of northern Mongolia in that period was much determined by the effect of a mantle plume, which showed two periods of activity: Late Paleozoic and Early Mesozoic. The long multistage evolution of the EMC was due to its localization on the periphery of the Late Paleozoic and Early Mesozoic areas of the plume’s influence. The Shivota and post-ore basites are considered to be comagmatic to the Late Permian–Early Triassic trachyandesite-basalt and Late Triassic–Early Jurassic trachyandesite series, respectively, which are similar to the products of Late Paleozoic and Early Mesozoic within-plate magmatism in northern Mongolia. The Selenga complex, which formed before the Shivota one, and the porphyry complex, which formed before the post-ore dike one, are differentiated gabbro-granite series. Gabbro-granitoid magmatism was initiated by the melting of rocks of continental lithosphere under the action of a plume. Later on, as the plume ascended to the surface and the lithosphere became thinner, the conditions were created favoring the lithosphere breakthrough and within-plate basaltoid magmatism.In geochemical features (high contents of LILE and LREE, low contents of HFSE and HREE) the studied basites are similar to the products of subduction magmatism. But this contradicts the geologic position of basites formed after the completion of subduction during the transition of the region to the rifting stage and during the rifting. The mantle metasomatized during the preceding subduction is regarded as the main source of basites. The high contents of alkalies and LREE in the volcanics of the post-ore dike complex and the REE patterns similar to the OIB ones evidence the influence of the plume on the magma formation. The high contents of incompatible trace elements and the Nd isotope composition corresponding to the weakly depleted mantle do not exclude a possible plume effect during the formation of the Selenga complex gabbroids. The geochemical features of the Shivota gabbros, comagmatic to volcanics produced during the Late Paleozoic within-plate activity, are partly transformed during the melt evolution in crustal chambers.The REE patterns of the EMC basites evidence that the evolution of ascending magma was accompanied by the fractionation of amphibole. During this process, ore elements were redistributed into mineral and concentrated in amphibole-containing rocks, from which metals were later mobilized by late melts and fluids. The evolution of basaltoid magmatism of the Selenga, Shivota, and porphyry complexes is regarded as a preliminary stage of ore formation, which was considerably responsible for the EMC productivity. 相似文献
7.
《Russian Geology and Geophysics》2014,55(2):153-176
The evolution of Late Paleozoic granitoid magmatism in Transbaikalia shows a general tendency for an increase in the alkalinity of successively forming intrusive complexes: from high-K calc-alkaline granites of the Barguzin complex (Angara–Vitim batholith) at the early stage through transitional from calc-alkaline to alkaline granites and quartz syenites (Zaza complex) at the intermediate stage to peralkaline granitoids (Early Kunalei complex) at the last stage. This evolution trend is complicated by the synchronous development of granitoid complexes with different sets and geochemical compositions of rocks. The compositional changes were accompanied by the decrease in the scales of granitoid magmatism occurrence with time. Crustal metaterrigenous protoliths, possibly of different compositions and ages, were the source of granitoids of the Angara–Vitim batholith. The isotopic composition of all following granitoid complexes points to their mixed mantle–crustal genesis. The mechanisms of granitoid formation are different. Some granitoids formed through the mixing of mantle and crustal magmas; others resulted from the fractional crystallization of hybrid melts; and the rest originated from the fractional crystallization of mantle products or the melting of metabasic sources with the varying but subordinate contribution of crustal protoliths. Synplutonic basic intrusions, combined dikes, and mafic inclusions, specific for the post-Barguzin granitoids, are direct geologic evidence for the synchronous occurrence of crustal and mantle magmatism. The geodynamic setting of the Late Paleozoic magmatism in the Baikal folded area is still debatable. Three possible models are proposed: (1) mantle plume impact, (2) active continental margin, and (3) postcollisional rifting. The latter model agrees with the absence of mafic rocks from the Angara–Vitim batholith structure and with the post-Barguzin age of peralkaline rocks of the Vitim province. 相似文献
8.
Hossein Azizi Ayten Hadi Yoshihiro Asahara Youssef Osman Mohammad 《Central European Journal of Geosciences》2013,5(4):523-537
The Iraqi Zagros Orogenic Belt includes two separate ophiolite belts, which extend along a northwest-southeast trend near the Iranian border. The outer belt shows ophiolite sequences and originated in the oceanic ridge or supra-subduction zone. The inner belt includes the Mawat complex, which is parallel to the outer belt and is separated by the Biston Avoraman block. The Mawat complex with zoning structures includes sedimentary rocks with mafic interbedded lava and tuff, and thick mafic and ultramafic rocks. This complex does not show a typical ophiolite sequences such as those in Penjween and Bulfat. The Mawat complex shows evidence of dynamic deformation during the Late Cretaceous. Geochemical data suggest that basic rocks have high MgO and are significantly depleted in LREE relative to HREE. In addition they show positive ? Nd values (+5 to+8) and low 87Sr/86Sr ratios. The occurrence of some OIB type rocks, high Mg basaltic rocks and some intermediate compositions between these two indicate the evolution of the Mawat complex from primary and depleted source mantle. The absence of a typical ophiolite sequence and the presence of good compatibility of the source magma with magma extracted from the mantle plume suggests that a mantle plume from the D″ layer is more consistent as the source of this complex than the oceanic ridge or supra-subduction zone settings. Based on our proposed model the Mawat basin represents an extensional basin formed during the Late Paleozoic to younger along the Arabian passive margin oriented parallel to the Neo-Tethys oceanic ridge or spreading center. The Mawat extensional basin formed without creation of new oceanic basement. During the extension, huge volumes of mafic lava were intruded into this basin. This basin was squeezed between the Arabian Plate and Biston Avoraman block during the Late Cretaceous. 相似文献
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四川盆地具有演化历史长、沉积盖层厚度大、油气资源丰富等特点,是我国大型含油气盆地之一。上扬子地区中、晚二叠世之间的峨眉山地幔柱活动改变了四川盆地古地理格局,造成地壳的快速抬升,盆地西南地区地壳抬升幅度最大,呈现古剥蚀高地,往北东方向的影响逐渐减弱,从而导致沉积环境自西南向北东由单一的海相依次转变为陆相、海陆过渡相至海相沉积。本文讨论了峨眉山大火成岩省的形成过程及对四川盆地油气储层的影响,认为峨眉山大火成岩省对四川盆地油气储层的影响主要体现在两个阶段、3种影响作用方式。两个阶段是指中二叠世末期和晚二叠世—早三叠世时期。3种方式是指峨眉山地幔柱导致的地壳抬升对下伏中二叠统灰岩储层的改造作用,表现为地幔柱核心区(大理—永仁)中二叠世地层发育风化壳岩溶型储层;峨眉山大火成岩省的火山喷发旋回对火山岩储层的空间发育的控制作用,发育了火山岩储层;峨眉山地幔柱活动控制的晚二叠世盆地构造格架对上覆沉积储层的控制作用,导致了峨眉山地幔柱外围伸展区(川东北—西北)发育海槽,控制了晚二叠世礁滩相沉积的发育等。峨眉山大火成岩省的形成过程不仅形成了优质的火山岩储层,同时也影响了沉积岩相的空间分布、改造了下伏碳酸盐岩的孔隙特征,进而控制了四川盆地的油气储层。 相似文献
11.
《International Geology Review》2012,54(9):1097-1121
The Coastal Accretionary Complex of central Chile constitutes the product of early Carboniferous to Late Triassic subduction at the rear of Chilenia, a continental terrane likely derived from Laurentia and accreted to southwestern margin of Gondwana during the Mid to Late Devonian. The complex contains basaltic metavolcanic sequences of the subducted oceanic lithosphere accreted to the active margin. In this paper, we address the tectonic setting of these rocks by means of a geochemical study in the coastal area of Pichilemu region, central Chile. The accreted fragments of oceanic crust occupy different structural levels, exhibit variable metamorphic grade, and have geochemical fingerprints that reveal a compositional heterogeneity of the subducted oceanic crust. The amphibolites have N to E-MORB compositions. Greenschist units include N-MORB and E-MORB transitional to OIB, and blueschists and greenschists interleaved within a single metavolcanosedimentary sequence have OIB signatures. Neodymium isotopic systematics indicate depleted and enriched mantle sources, whereas strontium isotopic systematics indicate seawater/rock interaction. The variety of rocks suggests formation in an oceanic setting characterized by shallow and deep mantle sources, such as plume-influenced ridge. Based on the geological, petrological, geochemical, and isotopic characteristics, we propose that the metavolcanic protoliths of the Pichilemu region formed relatively close to the western margin of the Chilenia terrane during the initial stage (late Cambrian–Early Devonian) of seafloor development and drifting of this continental block. Geochemical similarities with oceanic units accreted to the active margin south of the Pichilemu region indicate a regional pattern of the oceanic crust subducted under the Palaeozoic Chilean margin between, at least, 34°S and 39°S latitude, strongly supporting the activity of a mantle plume. This, in turn, can be correlated with the location of the Pacific plume generation zone in early Palaeozoic era, corroborating a Laurentian origin for the Chilenia terrane. 相似文献
12.
http://www.sciencedirect.com/science/article/pii/S1674987111001095 总被引：11，自引：2，他引：9
During the Late Mesozoic Middle Jurassic-Late Cretaceous,basin and range tectonics and associated magmatism representative of an extensional tectonic setting was widespread in southeastern China as a r... 相似文献
13.
页岩热演化史与页岩气的成烃、成藏过程关系极为密切.一方面,页岩热演化过程决定了页岩生烃过程、页岩气类型和生气量;另一方面,页岩有机孔隙的形成与页岩热演化过程密切相关.在前期热史恢复基础上,以锆石（U-Th）/He和沥青反射率Rb等古温标进行标定,模拟了川西南地区代表性钻孔下寒武统筇竹寺组页岩热演化史,探讨了页岩热演化过程与页岩气成烃、成藏的关系.研究结果表明,川西南地区下寒武统筇竹寺组页岩热演化过程和生烃史差异性明显,可以识别出两种模式:加里东期坳陷区,筇竹寺组页岩在加里东期成熟,中?晚二叠世期间快速演化定型,两个生烃高峰期分别出现在志留纪（生油高峰?湿气阶段）、中?晚二叠世（干气阶段）,此后再无明显的生烃活动;加里东期古隆起区,筇竹寺组页岩在加里东期未熟?低熟,晚海西期?燕山期持续增熟,亦存在两期生烃高峰,分别是中?晚二叠世（生油高峰阶段）、晚侏罗世?早白垩世（湿气?干气阶段）,筇竹寺组页岩生烃过程持续到晚白垩世末期.分析表明中?晚二叠世期间筇竹寺组页岩的埋深差异造成了其受峨眉山地幔柱热效应的影响不同,进而决定了加里东期坳陷区与隆起区筇竹寺组页岩热演化过程和生烃史差异,并最终导致了威远?犍为地区筇竹寺组页岩含气性优于盆地外围.综合川西南地区筇竹寺页岩生烃史和孔隙度演化模型,将川西南成藏条件相对优越的威远?犍为地区筇竹寺组页岩气成藏过程分为4个阶段:早古生代时期源?储?盖形成和生物气成藏阶段、中?晚二叠世期间初始成藏阶段、晚侏罗世?早白垩世主成藏阶段和晚白垩世以后调整改造阶段.该成果以页岩热演化过程为切入点解释了川西南威远?犍为地区与盆地外围下寒武统筇竹寺组页岩气成藏差异的原因. 相似文献
14.
在滇东南建水地区发现产于峨眉山玄武岩中的高镁火山岩包体,这对于地幔柱的形成演化具有重要研究意义.对这些包体进行了锆石U-Pb年代学、地球化学和岩矿分析.高镁火山岩包体具斑状结构,致密块状构造,斑晶主要为贵橄榄石和透辉石.13颗锆石U-Pb LA-ICP-MS加权平均年龄为259±2Ma(MSWD=1.9),显示与寄主岩石同期形成.包体岩石具有高镁(Mg~#=68～75)、低硅(SiO_2=45.11%～45.93%)特征,轻稀土元素(LREE)、高场强元素(HFSE)富集而重稀土元素(HREE)亏损,属于亚碱性、拉斑玄武岩系列,具有板内玄武岩(IPB)特征.火山岩包体的原始岩浆起源于石榴子石二辉橄榄岩低程度部分熔融的产物,岩浆演化过程中发生了橄榄石和单斜辉石的分离结晶作用,在侵位上升过程中未受明显的地壳混染作用.该高镁火山岩的存在,显示地幔柱除了垂直上升运动外,在地球深部不同的边界还有多次侧向扩展移动,表明滇东南晚二叠世存在峨眉山地幔柱的一个分支-地幔枝活动. 相似文献
15.
New data on composition and age of Precambrian granites and volcanic rocks in the southern part of the Lyapin structure (Northern Urals) are considered. The geochemical features of the igneous rocks are similar to those of the rocks formed in both divergent and convergent environments. In the Late Precambrian (583–553 Ma), the investigated area is assumed to have been a part of the active margin above the mantle plume. 相似文献
16.
Permian komatiites and associated basalts from the marine sediments of Chhongtash Formation, southeast Karakoram, Ladakh, India 总被引：1，自引：0，他引：1
Summary The Karakoram micro-plate is the southern most sector of the Central Asian micro-plate mosaic which was separated by a narrow
rift basin. A major rifting phase started during Permian time, which lead to drift of not only Karakoram but of the entire
Eurasian (Asian) Plate from Gondwana land. This was at a time when a prominent sequence of black argillites occupied most
part of the Karakoram Tethys basin. The geodynamic setting for this sequence may be interpreted as the evolution of a passive
margin affected by extensional tectonics. The extensional activity is evident from the extrusion of basalts and komatiitic
rocks in the region.
In this paper the geochemical relations between komatiites and basalts of the Chhongtash, southeast Karakoram are investigated.
The basaltic and komatiitic (ultrabasic) flows are petrologically and geochemically distinct, yet they display a close spatial
and temporal association, and they are related to each other through olivine and clinopyroxene fractionation. The chemical
characteristics of the ultrabasic to basic magmatism in the region is consistent with formation above a mantle plume that
impinged on the continental lithosphere. Hence, a model of partial melting in a mantle plume and fractional crystallization
in a deep-seated magma chamber is envisaged to explain the evolution of these volcanic rocks. The komatiite melts are interpreted
to have been derived by high degree partial melting of mantle plumes in the tail region, while the basalts were interpreted
to be the result of interaction of source plume with cool mantle through which the plume head passed. This study is the first
of its kind, to suggest a rift related nature in the Chhongtash, southeast Karakoram, that represent the initial stage of
Mesozoic rifting along the southern margin of Eurasia when Gondwana started to drift away from Eurasia. 相似文献
17.
南天山托云盆地晚白垩世——早第三纪玄武岩的地球化学特征 … 总被引：18，自引：0，他引：18
托云盆地晚白垩世－－早第三纪碱性橄榄玄武岩Ｓｒ、Ｎｄ、Ｐｂ同位素组成表明,本区玄武岩以低Ｓｒ、Ｐｂ和相对高的Ｎｄ同位素值（＾８７Ｓｒ／＾８６Ｓｒ为０．７０３５５４￣０．７０３８８４;＾１４３Ｎｄ／＾１４４Ｎｄ为０．５１２８３８￣０．５１２９０４;＾２０６Ｐｂ／＾２０４Ｐｂ为１８．００６３￣１８．４７２０;＾２０７Ｐｂ／＾２０４Ｐｂ为１５．４４１１￣１５．５０６０;＾２０８Ｐｂ／＾２０４Ｐｂ为３７． 相似文献
18.
WANG Yanbin WANG Yong LIU Xun FU Derong XIAO Xuchang QI Longshui . Institute of Geology Chinese Academy of Geological Sciences Beijing . Hebei College of Technology Tangshan 《Continental Dynamics》2001,(1)
1. Introduction The Tianshan Mountains is a typical intercontinental orogenic belt in the world. From late Carboniferous to Permian, the old Tianshan formed during the tectonic amalgamation of the Tarim block, Tianshan block and Siberia craton (Carroll et al, 1990). Mid-Cenozoic basalts are widely distributed in both the Tuyon basin of southwest Tianshan and its western part of Tianshan in Jierjisi in late Cretaceous-Paleogene period, which indicates the activation of the old Tianshan.… 相似文献
19.
中国东北晚中生代-新生代盆山体系构造演化及成因探讨 总被引：1，自引：0，他引：1
中国东北盆山体系主要形成和发展于晚侏罗世晚期-新近纪,经历了晚侏罗世晚期-早白垩世小盆山（盆岭）和晚白垩世-新近纪大盆山（盆山）两个阶段的构造发展过程.盆岭阶段起始于东北高原向盆岭体系转换的张家口期,全盛于义县-九佛堂期,萎缩于盆岭向盆山体系构造转换的沙海-阜新期,结束于张老公屯期（东山期）.盆山阶段经历了晚白垩世早期大规模拗陷、晚白垩世晚期拗陷萎缩、古近纪大规模裂谷和新近纪后裂谷拗陷.认为太平洋板块对盆山体系形成和发展有巨大的影响,但无论是板块、地幔柱和超级地幔柱均不太可能形成如此规模,又具北北东向的中-新生代岩浆岩带和盆山体系,更可能是超级地幔热带、地幔柱和东亚多向板块汇聚背景下,西太平洋板块俯冲共同作用的结果. 相似文献
20.
《Russian Geology and Geophysics》2007,48(2):141-156
The Erdenet-Ovoo magmatic center (EOMC) lies within the North Mongolian magmatic area formed through the interaction of a Permo-Triassic plume with the lithosphere in an environment of active continental margin. Two stages are recognized in the EOMC history: subduction stage with participation of basalt-andesite-dacite-rhyolite series and rifting stage with trachybasalt series. The granitoid magmatism (258–220 Ma) is expressed as the Selenge, Shivota, and ore-bearing porphyry complexes. The formation of the Selenge and Shivota granitoids was preceded by the intrusion of gabbroids. Trachybasalts formed during the granitoid magmatism after the Selenge complex, nearly synchronously with the Shivota and ore-bearing porphyry complexes. At the subduction stage of the EMC evolution, the plume influence is documented from the appearance of gabbros both depleted and enriched in lithophile trace elements similar to volcanic rocks of trachybasalt series and basaltoids of bimodal series in northern Mongolia. The Rb-Sr and Sm-Nd isotope characteristics of the enriched gabbros suggest the participation of a lower mantle source in their formation. The plume, as a heat carrier, led to a large-scale manifestation of volcanism and, obviously, a wide development of basic rocks of this stage at depth. The basic rocks were the source of granitoid magma that produced the Selenge granitoids. The protolith melted in the >50 km thick crust preventing the wide manifestation of basaltoid volcanism in that period. The increased plume influence, rifting, uplift of the region, and extension of the crust favored the basaltoid and granitoid (Shivota and ore-bearing porphyry) magmatism activity. 相似文献