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1.
The thermal and mechanical structures of the southern part of the Precambrian Indian Shield have been estimated using available heat flow data and shear stress profiles from olivine rheology. These and other geological, geochronological and geophysical data including deep seismic studies (DSS) profiles of Proterozoic Cuddapah basin on South Indian Shield, are utilized to examine thermal models for the evolution of Precambrian intracratonic, platform basins on the Archean lithosphere of Indian Shield. Evidence of mantle perturbations and cycles of thermal events are documented to be important in the Cuddapah basin's evolution. Haxby et al.'s (1976) thermal model has been shown to explain the Cuddapah basin's flexuring and magnitude of subsidence.  相似文献   

2.
Hudson Bay conceals several fundamental tectonic elements of the North American continent, including most of the ca. 1.9–1.8 Ga Trans-Hudson orogen (THO) and the Paleozoic Hudson Bay basin. Formed due to a collision between two cratons, the THO is similar in scale and tectonic style to the modern Himalayan–Karakorum orogen. During collision, the lobate shape of the indentor (Superior craton) formed an orogenic template that, along with the smaller Sask craton, exerted a persistent influence on the tectonic evolution of the region resulting in anomalous preservation of juvenile Proterozoic crust. Extensive products of 2.72–2.68 Ga and 1.9–1.8 Ga episodes of subduction are preserved, but the spatial scale of corresponding domains increases by roughly an order-of-magnitude (to 1000 km, comparable to modern subduction environments) from the Archean to the Proterozoic. Based on analysis of gravity and magnetic data and published field evidence, we propose a new tectonic model in which Proterozoic crust in the southeastern third of Hudson Bay formed within an oceanic or marginal-basin setting proximal to the Superior craton, whereas the northwestern third is underlain by Archean crust. An intervening central belt truncates the southeastern domains and is interpreted to be a continental magmatic arc.Thick, cold and refractory lithosphere that underlies the Bay is well imaged by surface-wave studies and comprises a large component of the cratonic mantle keel beneath North America. The existence of an unusually thick mantle root indicates that subduction and plate collision during the Trans-Hudson orogeny were ‘root-preserving’ (if not ‘root-forming’) processes. Although the Hudson Bay basin is the largest by surface area of four major intracratonic basins in North America, it is also the shallowest. Available evidence suggests that basin subsidence may have been triggered by eclogitization of lower-crustal material. Compared to other basins of similar age in North America, the relatively stiff lithospheric root may have inhibited subsidence of the Hudson Bay basin.  相似文献   

3.
R. Varne  J.D. Foden 《Tectonophysics》1987,140(2-4):275-295
In western Tasmania, small Precambrian regions are surrounded by a ramifying system of troughs filled with Cambrian sedimentary and volcanic rocks, and ophiolite complexes. The volcanic associations include a rift-related olivine tholeiite association, dacite-rhyolite and andesite associations, and a low-Ti, high-Mg andesite-tholeiite ophiolite association, and may have formed during a long-lived period of crustal thinning, punctuated by episodes of crustal rupturing, magmatism, and small scale rifting. Such extensional tectonism could occur in an active continental margin associated with strike-slip faulting of regional scale, and the volcanic associations may together constitute an igneous assemblage characteristic of magmatism in a transcurrent tectonic regime within an active continental margin undergoing break-up.

The western Tasmanian Cambrian palaeogeography and volcanism preserve a transitional stage between the Late Proterozoic Kanmantoo regime of sedimentary basins with little volcanism developed at the rifting margin of the Proterozoic craton, and the tectonic regime of the Palaeozoic Lachlan Fold Belt where the Cambrian volcanic rocks are dominated by island-arc associations and the rift-related olivine tholeiite association is absent. Eastern Australian lithosphere may have grown by the insertion of newly-formed igneous complexes within the stretched and rifted continental margin, as well as by the accretion of “terrenes” and the addition of packets of subduction complexes which developed off-shore.  相似文献   


4.
The evolution of the Indian Shield has been envisaged from the analysis of available tectono-lithostratigraphic, geochronological, geochemical and geophysical data. It appears that the Dharwar schist belts and their equivalents, except the Kolar schist belt, are not typical greenstone belts, but are representative of a transitional era of rapid transformation from simatic to sialic crust. In the Archaean—Proterozoic tract of India, relics of rocks older than 3.0 b.y. are identified in five widely separated regions of distinct tectono-litho-stratigraphic assemblages which probably represent the primordial continental nucleii. It is suggested that the growth of the Indian Shield has taken place through nucleation, accretion and merger into three protocontinents named Dharwar, Aravalli and Singhbhum. The cratonisation of the Indian unit seems to have been rapid and almost completed by the middle Proterozoic, as there is no significant variation in the composition of the clastic sediments and basalts from middle Proterozoic onwards. The continental nucleii appear to merge along the deep-seated lineaments, which are reflected on the tectonic map of India. Further, the Dharwar, Aravalli and Singhbhum protocontinents also seem to merge along a Y=shaped Narmada—Son—Godavari lineament which along with the Mahanadi lineament, between the two continental nucleii of the Singhbhum protocontinent have later developed into rift valleys.  相似文献   

5.
The Aravalli mountain range (AMR) in the northwestern part of the Indian Peninsula consists of two main Proterozoic metasedimentary and metaigneous sequences, the Aravalli and Delhi Supergroups, respectively, which rest over the Archaean gneissic basement. A synthesis and reinterpretation of the available geological, geochronological and geophysical data, including results of own field work and geophysical interpretations pertaining to the AMR, indicate its origin as an inverted basin: rifting into granitoid basement began ca. 2.5; Ga ago with Aravalli passive rifting (ca. 2.5–2.0 Ga) and Delhi active rifting (ca. 1.9–1.6 Ga). Associated mafic igneous rocks show both continental and oceanic tholeiitic geochemistry and are comparable with Phanerozoic, rift-related magmatic products. Available data showed no conclusive evidence for oceanic lithoshere and island-arc/active margin magmatic activity in the AMR. Subsequent inversion and orogeny (Delhi orogeny, ca. 1.5-1.4 Ga) lead to complex deformation and metamorphism. Only in the western and central zones has the basement been involved in this mid-Proterozoic (Delhi) deformation, whereas it is unaffected in the eastern part, except for local shear zones mainly along the basement/cover interface. The grade of metamorphism increases from the greenschist facies in the east to the amphibolite facies in the west with local HP assemblages. These latter are explained by rapid burial and exhumation of thin and cool continental lithosphere. Subsequently, during a final, mild phase of inversion, the Vindhyan basins consisting mainly of sandstones, limestones and shales, flanking the AMR formed which are comparable to foreland basins. The tectonic evolution of the AMR is therefore interpreted as an example of a major inverted continental rift and of a Proterozoic intra-continental orogen.  相似文献   

6.
安徽北淮阳构造带基底变质岩的构造属性   总被引:3,自引:2,他引:1  
安徽北淮阳构造带的基底由一套变火山沉积岩建造 (即原称庐镇关群 )所组成。岩类学、岩石地球化学、年代学的研究表明 ,这套火山岩属碱性玄武岩系列、拉斑玄武岩系列和钙碱性玄武岩系列 ,分别形成于中元古宙陆内裂解 (扩张 )带和晚元古宙岛弧两种构造环境 ,其中以岛弧环境火山岩为主要部分 ,由此可以证明北淮阳构造带是在中元古宙陆内裂解带基础上发展起来的古弧系 ,具有大陆型基底性质  相似文献   

7.
The widespread records of mafic intrusives (both sills and dykes) are reported from the Proterozoic sedimentary basins of the Indian Shield. Amongst them, the Bijawar basin is also intruded by Paleoproterozoic (ca. 1.98−1.97 Ga) mafic sills. We provide first hand information on petrological and geochemical characteristics of these mafic sills together with a few NW-trending mafic dykes belong to the Jhansi swarm emplaced within the Bundelkhand craton, adjacent to the Bijawar basin. These Paleoproterzoic mafic intrusive rocks, i.e. sills and dykes, are believed to be integral parts of the Jhansi LIP, identified in the Bundelkhand craton. The studied mafic magmatic samples are medium- to coarse-grained and contain doleritic mineral compositions and textures. Geochemically, the mafic sill samples of the Bijawar basin, which belong to the Darguwan-Surjapura mafic sills (DSMS), are sub-alkaline basaltic-andesite to andesite in character. They are co-genetic in nature and show close geochemical similarities with a set of NW-trending mafic dykes (low-Ti) emplaced in the Bundelkhand craton. On the other hand, another set of NW-trending mafic dykes (high-Ti) of the Bundelkhand craton have distinct geochemical nature; likely to have different genetic history. The rare-earth element contents and trace-element modeling suggest that the DSMS and low-Ti dyke samples are likely to be derived from a melt generated ≥20 % melting of a shallower mantle source (spinel stability field), whereas the high-Ti dyke samples show their derivation from a melt generated through ≤15 % melting of the similar mantle source but at deeper level (garnet or garnet-spinel transition stability field); with a substantiate percentage of olivine fractionation of melts before crystallization. Their emplacement in an intracratonic tectonic regime and role of plume in the genesis of these rocks are suggested. The geochemical signature also indicates the role of an ancient (Archean) subduction event that has metasomatized the mantle before the cratonization. Their spatiotemporal correlation with other similar magmatic events of the globe indicate that the Bundelkhand craton was closer to the Karelia-Kola craton (Baltica Shield), North China craton and northern Superior craton, which could be part of the Columbia supercontinent, during its assembly.  相似文献   

8.
The Saharan Metacraton   总被引:2,自引:0,他引:2  
This article introduces the name “Saharan Metacraton” to refer to the pre-Neoproterozoic––but sometimes highly remobilized during Neoproterozoic time––continental crust which occupies the north-central part of Africa and extends in the Saharan Desert in Egypt, Libya, Sudan, Chad and Niger and the Savannah belt in Sudan, Kenya, Uganda, Congo, Central African Republic and Cameroon. This poorly known tract of continental crust occupies 5,000,000 km2 and extends from the Arabian-Nubian Shield in the east to the Tuareg Shield to the west and from the Congo craton in the south to the Phanerozoic cover of the northern margin of the African continent in southern Egypt and Libya. The term “metacraton” refers to a craton that has been remobilized during an orogenic event but is still recognizable dominantly through its rheological, geochronological and isotopic characteristics. Neoproterozoic remobilization of the Saharan Metacraton was in the forms of deformation, metamorphism, emplacement of igneous bodies, and probably local episodes of crust formation related to rifting and oceanic basin development. Relics of unaffected or only weakly remobilized old lithosphere are present as exemplified by the Archean to Paleoproterozoic charnockites and anorthosites of the Uweinat massif at the Sudanese/Egyptian/Libyan boarder. The article explains why the name “Saharan Metacraton” should be used, defines the boundaries of the metacraton, reviews geochronological and isotopic data as evidence for the presence of pre-Neoproterozoic continental crust, and discusses what happened to the Saharan Metacraton during the Neoproterozoic. A model combining collisional processes, lithospheric delamination, regional extension, and post-collisional dismembering by horizontal shearing is proposed.  相似文献   

9.
华北克拉通北缘与盆地流体有关的若干矿床实例   总被引:7,自引:0,他引:7  
与华南一样,在华北克拉通北缘及其增生带也有与盆地流体有关的矿床产出。矿床的生成总是与张裂型沉积盆地有关。根据基底大地构造性质和盆地动力学演化特征,可划分出两个与盆地流体有关的、特征各异的金属成矿省:1)华北克拉通北部元古代金.多金属成矿省,在克拉通内部,边缘元古代裂谷增生期生成沉积喷流型硫多金属矿床和沉积岩容矿的微细浸染型金矿床;2)大兴安岭中南段古生代锡.多金属成矿省,在克拉通北缘早/晚古生代增生带的张裂型沉积盆地内分别生成各具特征的铅锌/锡-多金属矿床。  相似文献   

10.
南非境内矿产资源种类繁多、储量巨大,其内部的构造单元包括一个太古宙克拉通与一系列元古宙-古生代造山带,以及一个代表弧后前陆沉积系统的卡鲁盆地(狭义)。文章结合区域构造演化与成矿关系,将南非划分为6个Ⅲ级成矿区带:太古宙卡普瓦尔克拉通金-铀、铁-铜-铂族元素、金刚石成矿区,古元古代林波波金-金刚石成矿,古元古代海斯铁-锰成矿带,中元古代那马奎铜-铅-锌多金属成矿,古生代开普褶皱带钨-锡-铜-钼多金属成矿带,古生代-中新生代卡鲁盆地铀-金刚石-砂金成矿区。  相似文献   

11.
The kimberlite fields scattered across the NE part of the Siberian Craton have been used to map the subcontinental lithospheric mantle (SCLM), as it existed during Devonian to Late Jurassic time, along a 1000-km traverse NE–SW across the Archean Magan and Anabar provinces and into the Proterozoic Olenek Province. 4100 garnets and 260 chromites from 65 kimberlites have been analysed by electron probe (major elements) and proton microprobe (trace elements). These data, and radiometric ages on the kimberlites, have been used to estimate the position of the local (paleo)geotherm and the thickness of the lithosphere, and to map the detailed distribution of specific rock types and mantle processes in space and time. A low geotherm, corresponding approximately to the 35 mW/m2 conductive model of Pollack and Chapman [Tectonophysics 38, 279–296, 1977], characterised the Devonian lithosphere beneath the Magan and Anabar crustal provinces. The Devonian geotherm beneath the northern part of the area was higher, rising to near a 40 mW/m2 conductive model. Areas intruded by Mesozoic kimberlites are generally characterised by this higher, but still ‘cratonic' geotherm. Lithosphere thickness at the time of kimberlite intrusion varied from ca. 190 to ca. 240 km beneath the Archean Magan and Anabar provinces, but was less (150–180 km) beneath the Proterozoic Olenek Province already in Devonian time. Thinner Devonian lithosphere (140 km) in parts of this area may be related to Riphean rifting. Near the northern end of the traverse, differences in geotherm, lithosphere thickness and composition between the Devonian Toluopka area and the nearby Mesozoic kimberlite fields suggest thinning of the lithosphere by ca. 50–60 km, related to Devonian rifting and Triassic magmatism. A major conclusion of this study is that the crustal terrane boundaries defined by geological mapping and geophysical data (extended from outcrops in the Anabar Shield) represent major lithospheric sutures, which continue through the upper mantle and juxtapose lithospheric domains that differ significantly in composition and rock-type distribution between 100 and 250 km depth. The presence of significant proportions of harzburgitic and depleted lherzolitic garnets beneath the Magan and Anabar provinces is concordant with their Archean surface geology. The lack of harzburgitic garnets, and the chemistry of the lherzolitic garnets, beneath most of the other fields are consistent with the Proterozoic surface rocks. Mantle sections for different terranes within the Archean portion of the craton show pronounced differences in bulk composition, rock-type distribution, metasomatic overprint and lithospheric thickness. These observations suggest that individual crustal terranes, of both Archean and Proterozoic age, had developed their own lithospheric roots, and that these differences were preserved during the Proterozoic assembly of the craton. Data from kimberlite fields near the main Archean–Proterozoic suture (the Billyakh Shear Zone) suggest that reworking and mixing of Archean and Proterozoic mantle was limited to a zone less than 100 km wide.  相似文献   

12.
早前寒武纪地质及深成构造作用研究进展   总被引:4,自引:0,他引:4  
早前寒武纪地质的研究进展主要表现在准大陆克拉通早期构造演化,克拉通及古老造山带深层结构,元古代超大陆恢复对比、早期地壳性质及生长等主要问题上开展多学科研究计划的实施。其中,同位素年代学,特别是锆石U-Pb方法,地震反射、P-T计算及古地磁研究对前寒武纪地质学的进展具有重要的推动作用。和个古陆克拉通区域地质学的持质研究积累,不断产生新的认识,这种新的科学思想涉及到早期陆壳组成及区划,太古代克拉通化历史,太古代-元古代界限及性质,元古代造山带网络与克拉进陆块拼合,大陆下地壳剖面及其组成等同题。华北早前寒武纪地质演化研究中的重要问题包括:华北麻粒岩相带与克拉通基底构造的关系,克拉通基底构造区域,早期陆壳性质及其记录的重大构造一热事件幕,华北克拉通与世界典型陆块构造演化对比等。  相似文献   

13.
中生代华北克拉通破坏是目前引人关注的研究课题。鉴于目前一些文章在表达克拉通状态时引用的地质图件不准确,忽略了华北克拉通从古至今的不同阶段的演化,不能正确的表达克拉通在破坏之前或之后的状态,本文强调华北克拉通破坏前的状态是研究的重要基础。华北克拉通是经历过多期克拉通化形成的。  相似文献   

14.
A.B. Roy   《Gondwana Research》2004,7(2):387-406
The Indian crust, generally regarded as a stable continental lithosphere, experienced significant tectono-thermal reconstitution during the Phanerozoic. The earliest Phanerozoic tectonic process, which grossly changed the geological and geophysical character of the Precambrian crust, was during the Jurassic when this crustal block broke up from the Gondwana Supercontinent. There were two earlier abortive attempts to fragment the supercontinent in the Palaeozoic. Different types of geological processes were associated with these aborted events. The first was the intrusion of anorogenic alkali granites during the Early Palaeozoic (at 500±50 Ma), while the second was linked with formation of the Gondwana rift basins during Late Palaeozoic. The tectonic history of the Indian Shield subsequent to its separation from the Gondwanaland at around 165 Ma is a complex account of its northward journey, which was culminated with its collision with the northern continental blocks producing the mighty Himalayas in the process. Considerable reconstitution of the Indian Shield took place due to magma underplating when this lithospheric block passed over the four mantle plumes. While the underplating events grossly changed the geophysical character of the Indian Shield in isolated patches, the propagation of the underplated materials was assisted by the deep crustal fractures (geomorphologically expressed as lineaments), which formed during the break-up of the Gondwanaland. Several of these deep fractures evolved through the reactivation of the pre-existing (Precambrian) tectonic grains, while some others developed as new fractures in response to either the extensional stresses generated during the supercontinental break-up or the plume-lithosphere reactions. Significant geomorphological changes occurred in peninsular India subsequent to the continental collision. Most of these changes were brought about by the movements along the lineaments, which fragmented the Indian Shield into a number of rigid crustal blocks. The present day seismic behaviour of the Indian Shield is a reflection of movements of the rigid crustal blocks relative to each other. An interesting feature of the Phanerozoic geological history of the Indian Shield is the evolution of a number of sedimentary basins under different tectono-thermal regimes.  相似文献   

15.
The compositional structure and thermal state of the subcontinental lithospheric mantle (SCLM) beneath the Kalahari Craton and the surrounding mobile belts have been mapped in space and time using >3400 garnet xenocrysts from >50 kimberlites intruded over the period 520–80 Ma. The trace-element patterns of many garnets reflect the metasomatic refertilisation of originally highly depleted harzburgites and lherzolites, and much of the lateral and vertical heterogeneity observed in the SCLM within the craton is the product of such metasomatism. The most depleted, and possibly least modified, SCLM was sampled beneath the Limpopo Belt by early Paleozoic kimberlites; the SCLM beneath other parts of the craton may represent similar material modified by metasomatism during Phanerozoic time. In the SW part of the craton, the SCLM sampled by “Group 2” kimberlites (>110 Ma) is thicker, cooler and less metasomatised than that sampled by “Group 1” kimberlites (mostly ≤95 Ma) in the same area. Therefore, the extensively studied xenolith suite from the Group 1 kimberlites probably is not representative of primary Archean SCLM compositions. The relatively fertile SCLM beneath the mobile belts surrounding the craton is interpreted as largely Archean SCLM, metasomatised and mixed with younger material during Paleoproterozoic to Mesoproterozoic rifting and compression. This implies that at least some of the observed secular evolution in SCLM composition worldwide may reflect the reworking of Archean SCLM. There are strong correlations between mantle composition and the lateral variations in seismic velocity shown by detailed tomographic studies. Areas of relatively low Vp within the craton largely reflect the progressive refertilisation of the Archean root during episodes of intraplate magmatism, including the Bushveld (2 Ga) and Karroo (ca. 180 Ma) events; areas of high Vp map out the distribution of relatively less metasomatised Archean SCLM. The relatively low Vp of the SCLM beneath the mobile belts around the craton is consistent with its fertile composition. The seismic data may be used to map the lateral extent of different types of SCLM, taking into account the small lateral variations in the geotherm identified using the techniques described here.  相似文献   

16.
四川海相原型盆地的建设与改造   总被引:1,自引:1,他引:0       下载免费PDF全文
王清晨  蔡立国 《地质科学》2011,46(1):92-119
我们把沉积盆地的演化分为建设期和改造期两大阶段,并提出原型盆地恢复的两项主要任务为:重塑盆地建设期的种种特征(包括盆地边界、沉积环境、大地构造背景等)和研究盆地改造期的构造演化特征.对四川海相原型盆地原始边界的地震层析成像研究表明,其结晶基底的北界位于秦岭-大别山造山带下,西北界在松潘-甘孜造山带下,西界和西南界大致与...  相似文献   

17.
选取青海南部治多-杂多地区石炭纪-三叠纪的砂岩、粉砂岩样品,进行主量元素地球化学分析,利用分析结果判别物源区大地构造背景,探讨北羌塘盆地的性质及演化。研究结果表明:北羌塘中段的治多-杂多地区物源区大地构造背景早石炭世为被动大陆边缘;早中二叠世为被动大陆边缘、活动大陆边缘和大陆岛弧;晚三叠世为被动大陆边缘、活动大陆边缘和大陆岛弧。结合地层学、沉积学和岩石学,治多-杂多地区的沉积盆地经历了早石炭世被动陆缘克拉通盆地-早中二叠世裂陷盆地和早中三叠世被动边缘克拉通盆地-晚三叠世弧后前陆盆地的两个演化旋回,体现了金沙江缝合带和甘孜-理塘缝合带成生发展在研究区内的沉积响应。  相似文献   

18.
The geology of the southeastern and southwestern margins of the Guaporé Shield is described. The Shield rocks comprise high-grade granulite and low-grade greenschist sequences. These rocks are poorly known. Oldest recorded ages include Transamazonian datings (± 2 Ma). The margins of the shield show the development of a mobile belt formed by rocks of Upper Proterozoic to Cambrian age. Within this mobile belt, the Cuiabá Group of uncertain (but possibly Upper Proterozoic) age outcrops to the east and shows tectonic contacts with younger rocks that span the Vendian (Upper Proterozoic) to Cambrian age. The rocks of Vendian to Cambrian age form three isolated elongated basins which show evidence of fault control. The axes of these basins are equally separated by angles of ~ 120° and meet at a triple junction near Corumbá. The stratigraphy of the Vendian to Cambrian basins is correlated from Bolivia to Brazil, based on tectonic continuity, sedimentological similarity and fossil content. The central location at Corumbá shows instability since the Middle Proterozoic when important igneous activity is recorded at Rincon del Tigre (Bolivia) and in Brazil. This igneous activity is interpreted as being related to hot-spot activity in an intercratonic setting from which the younger Upper Proterozoic basins originated.  相似文献   

19.
南海北部深水盆地沉积-构造的差异性及其油气意义   总被引:5,自引:3,他引:2  
南海北部深水区自西向东依次分布着琼东南盆地、珠江口盆地、台西南盆地等新生代被动陆缘盆地,这些盆地经历了大致相当的从裂陷到坳陷的构造演化史,但在张裂活动过程中存在着明显的沉积-构造的差异性。构造沉降特征分析显示:在同一构造带上自西向东有盆地主要构造沉降发生的时段逐步变晚的趋势;在不同构造带上自北向南有盆地主要构造沉降发生的时段逐步变晚的趋势。这种沉积-构造的差异性对烃源岩的发育类型、分布及生储盖组合等方面有明显的控制作用,表现为:裂谷期构造沉降幅度大的盆地,陆相烃源岩发育,以陆生陆储陆盖型成藏组合为主;裂后期构造沉降幅度大的盆地,海相烃源岩发育规模较大,海生海储海盖型成藏组合及混生海储海盖型生储盖组合所占分量逐渐增多。推测渐新统湖相-湖沼相及海陆过渡相源岩和中新统海相烃源岩应是南海北部深水区油气的主要来源,陆生海储海盖型、海生海储海盖型及混生海储海盖型生储盖组合应是深水区基本生储盖组合类型。  相似文献   

20.
During the Late Mesozoic and Cenozoic, extension was widespread in Eastern China and adjacent areas. The first rifting stage spanned in the Late Jurassic–Early Cretaceous times and covered an area of more than 2 million km2 of NE Asia from the Lake Baikal to the Sikhot-Alin in EW direction and from the Mongol–Okhotsk fold belt to North China in NS direction. This rifting was characterized by intracontinental rifts, volcanic eruptions and transform extension along large-scale strike–slip faults. Based on the magmatic activity, filling sequence of basins, tectonic framework and subsidence analysis of basins, the evolution of this area can be divided into three main developmental phases. The first phase, calc-alkaline volcanics erupted intensely along NNE-trending faults, forming Daxing'anling volcanic belt, NE China. The second phase, Basin and Range type fault basin system bearing coal and oil developed in NE Asia. During the third phase, which was marked by the change from synrifting to thermal subsidence, very thick postrift deposits developed in the Songliao basin (the largest oil basin in NE China).Following uplift and denudation, caused by compressional tectonism in the near end of Cretaceous, a Paleogene rifting stage produced widespread continental rift systems and continental margin basins in Eastern China. These rifted basins were usually filled with several kilometers of alluvial and lacustrine deposits and contain a large amount of fossil fuel resources. Integrated research in most of these rifting basins has shown that the basins are characterized by rapid subsidence, relative high paleo-geothermal history and thinned crust. It is now accepted that the formation of most of these basins was related to a lithospheric extensional regime or dextral transtensional regime. During Neogene time, early Tertiary basins in Eastern China entered a postrifting phase, forming regional downwarping. Basin fills formed in a thermal subsidence period onlapped the fault basin margins and were deposited in a broad downwarped lacustrine depression. At the same time, within plate rifting of the Lake Baikal and Shanxi graben climaxed and spreading of the Japan Sea and South China Sea occurred. Quaternary rifting was marked by basalt eruption and accelerated subsidence in the area of Tertiary rifting. The Okinawa Trough is an active rift involving back-arc extension.Continental rifting and marginal sea opening were clearly developed in various kind of tectonic settings. Three rifting styles, intracontinental rifting within fold belt, intracontinental rifting within craton and continental marginal rifting and spreading, are distinguished on the basis of nature of the basin basement, tectonic location of rifting and relations to large strike–slip faults.Changes of convergence rates of India–Eurasia and Pacific–Eurasia may have caused NW–SE-trending extensional stress field dominating the rifting. Asthenospheric upwelling may have well assisted the rifting process. In this paper, a combination model of interactions between plates and deep process of lithosphere has been proposed to explain the rifting process in East China and adjacent areas.The research on the Late Mesozoic and Cenozoic extensional tectonics of East China and adjacent areas is important because of its utility as an indicator of the dynamic setting and deformational mechanisms involved in stretching Lithosphere. The research also benefits the exploration and development of mineral and energy resources in this area.  相似文献   

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