古生代
- 与 古生代 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Stratabound deposits in Archeozoio era: of the early Archeozoic, there are Qianxi iron ore deposit in volcanic and sedime...
层控矿床的成矿时代,由于其成矿的复杂性和成矿时间的不确定性,我们只能以地质一构造的巨旋回为准,分为太古宙、元古宙和显生宙的古生代和中-新生代四期。
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Himalaya, which formed on the basement of the Pan-African orogenic event at about 550 Ma BP and experienced Ordovician to Devonian platform sedimentation, was transformed into to a back-arc extensional-rifted zone at the end of the Carboniferous. The Yarlung Zangbo ophiolitic mélange zone is a Mesozoic back-arc spreading basin corresponding to the Gangdise paleo-island arc zone on the south side of the Tethyan Ocean. The Gangdise zone experienced island-arc orogeny in the Late Paleozoic. The very significant differences in geology on both sides of the Bangong Co-Nujiang suture zone suggest that the suture zone is not only the northern boundary of Gondwanaland and the boundary between the Indian (Yunnan-Tibet) stratigraphic realm and the South China (Qiangtang-Sanjiang) stratigraphic realm, but also the relics of subductional collision and final extinction of the Phanerozoic Tethyan Ocean after the breakup of the Neoproterozoic supercontinent Rodinia. The basic point of study of the collisional orogenic processes of the plateau is the structure and composition of the archipelagic arc-basin tectonic realm of three different stages bounded by three rigid paleocontinental blocks (Gondwanaland, Laurasia and Pan-Cathaysian) and the mutual constraining, transformation and coupling of various material movement forms.
喜马拉雅奠基于5.5亿年左右的泛非造山事件基底上,历经奥陶纪至泥盆纪台地沉积,并于石炭纪末转化为印度板块北缘的弧后伸展裂陷带;雅鲁藏布江蛇绿混杂岩带曾是特提斯大洋南侧与冈底斯古岛弧带相对应的中生代弧后扩张盆地;冈底斯带曾经历了晚古生代岛弧造山作用;班公湖-怒江带两侧大量地质特征重大差异表明,班公湖-怒江带是冈瓦纳大陆北界,是印度地层区和华南地层区的分界,是新元古代Rodinia超大陆解体后显生宙特提斯大洋俯冲,消减,碰撞,最后消亡的遗迹。
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In the period of Mesozoic-Palaeozoic, Caledonian events and the evolution of Hercynian -early indo-Chinese cycle are experienced in two-phase marine passive continental margin and Craton basin in the lower and middle Yangtze Region, by which stable enormous thick Mesozoic-Palaeozoic deposites are induced, six sets of source rocks are produced, it has a strong capacity of hydrocarbon generation.
通过构造演化特征分析了海相烃源岩的发育,中、下扬子区中-古生代经历了加里东和海西-早印支旋回两个阶段的海相被动大陆边缘和克拉通盆地演化,形成了岩性稳定的巨厚中-古生界,发育了6套烃源岩,具有较强的生烃能力。
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Surprisingly, cadalene, retene and perylene, usually used as the terrestrial biomarkers, are abnormally abundant in the Lower Paleaozoic source rocks.
卡达烯、惹烯和苝在下古生界烃源岩中的普遍存在充分说明它们不是可靠的陆源标志物,早古生代繁盛的兰绿藻等浮游植物无疑也是其主要的生物来源。
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Finally, it can be concluded for the first time that there was a large time gap between diagentic process of the volcanic rocks related to the Dapingzhang VHMS deposit and the ore-forming process, then a ore-forming model of the Dapingzhang deposit can be made, that is, the deposit passed through two important stages: the ore-forming metals concentrated during formation of the Early Palaeozoic spilite-quartz keratophyre on the island-arc belt, and the mineralization caused by the Late Palaeozoic magmation.
最后,首次提出与块状硫化物矿床有关的火山岩成岩过程和成矿过程可以有较大的时间间隔。在此基础上建立了大平掌矿床的成矿模式,并认为成矿作用可能经历了两个重要阶段,即早古生代岛弧型细碧岩-石英角斑岩建造形成过程中成矿元素的初始富集和晚古生代岩浆活动最终导致成矿。
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In the early Paleozoic and Indosinian cycle, the tectonic movement is weak, and the rock has acoustic emission once, whose maximum paleo-stress is 13.3MPa and 24MPa, moreover the Majiang ancient reservoir is in the mainly accumulation period; the high frequency and intensity paleo-stress correspond to the Majiang ancient reservoir's reservoir comes into being or destruction. The single Neopaleozoic acoustic emission whose maximum paleo-stress is 92.6MPa means the reservoir comes into being.
在早古生代末期和印支期构造运动较弱,测试岩石的发声一次,古应力值分别为13.3MPa和24MPa,是麻江古油藏的主要成藏期;声发射次数较多或者古应力值较大时的时期,主要对应于麻江古油藏储层的发育期和油藏大规模破坏期。
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Based on the date of outcrop, log and lithology, sequence stratigraphic division and correlation were made on Neopaleozoic in south of North China Basin, and high-precision geologic correlation framework was built up in the basin.2. In the term of sedimentary features of Neopaleozoic in south of North China Basin, lateral variation of sedimentary facies was studied selectively in Benxi-Taiyuan Formation, Shanxi Formation, Lower Shihezi Formation, Upper Shihezi Formation and Shiqianfeng Formation. Lithofacies paleographic features and the sedimentary evolutionary process of Late Paleozoic in south of North China Basin were worked also.3. On the basis of sand-bodies Isopach figure drawing, the distribution of major reservoir sand-bodies of Neopaleozoic in south of North China Basin was studied. Basing on the distribution of sand-bodies in sequence stratigraphic framework, combining the development and distribution features of barrier and underwater distributary channel, there is a disquisition on the distribution regularity of pay reservoir sand-bodies of Neopaleozoic in this area.
以露头、测井和岩性资料为基础,对华北盆地南部上古生界进行了层序地层的划分与对比工作,建立了盆地范围内的高精度地层对比格架。2、根据华北盆地南部上古生界的沉积特点,按本溪组—太原组、山西组、下石盒子组、上石盒子组和石千峰组5个层组分别开展了沉积相的横向变化对比研究,并以此为基础探讨了华北盆地南部晚古生代的岩相古地理特征及其沉积演化过程。3、以编制砂体等厚图的方式研究了华北盆地南部上古生界主要储集砂体的平面展布规律,并以层序地层格架下的砂体展布研究为基础,从沉积体系控制下的砂体分布特点出发,结合障壁岛与水下分流河道的发育与分布特点,系统深入地开展了区内上古生界有利储集砂体的分布规律研究。
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Kalamaili suture zone is an important plate boundary in north Xinjiang, and there are plenty of Neopaleozoic volcanic rocks around itThese volcanic rocks are enriched in LILEs and relatively depleted in HFSEs, and they are also characterized by high Nb, Zr, TiO2 contents and Zr/Y, Nb/Y ratios, and depleted SrNd isotopesThe characteristics of these volcanic rocks suggest that they were produced in postcollisional periodThe postcollisional volcanic rocks around Kalamaili suture zone become younger from west to east, which indicates that this suture zone entered postcollisional period gradually from west to east, and reflects that the Kalamaili Ocean had been closed gradually from west to eastAs to the Kalamaili suture zone in postcollisional period, the lithosphere extended and thinned, and the asthenosphere materials upwelled and melted partially, and intensive mantle convection occurred, leading to a plenty of mantlederived magmas underplating the suture zoneThe lithospheric mantle metasomatized by fluid in subduction period melted partially under decompression and high temperature, the resulting melts contaminated the underplating asthenospheric materials, and the erupted lavas became the Neopaleozoic postcollisional volcanic rocks
卡拉麦里缝合带是北疆的一条重要界线,沿该带广泛发育晚古生代火山岩。这些火山岩具有LILE相对富集、HFSE相对亏损的特征,且具有较高的Nb、Zr、TiO2含量和Zr/Y、Nb/Y比值,SrNd同位素主要表现出亏损的特征。综合分析表明,这些火山岩形成于后碰撞期。对卡拉麦里缝合带而言,从西向东后碰撞火山岩的时代逐渐变新,表明该缝合带从西向东逐渐演化进入后碰撞期,这从侧面反映了卡拉麦里洋盆是从西向东逐渐关闭的。对卡拉麦里缝合带而言,在后碰撞期,岩石圈伸展减薄,软流圈地幔物质上涌并发生部分熔融,加上地幔对流作用强烈,使得缝合带下产生了大规模的幔源岩浆底垫;先前在洋壳消减期被流体交代提取过的岩石圈地幔也在低压高温下发生部分熔融,形成的熔体混染了底垫的软流圈物质并喷发,形成了晚古生代的后碰撞期火山岩。
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Based on the regional tectonic evolution, combined with the high precision isotopic ages from this paper and other geologists, we have some new acquaintances as follows: 1 There has no Caledonian granite belt distributed in north margin of North China Craton. So, the traditional evolving model of North China Carton, which formed on this idea and the acquaintance about the collision of North China plate and Siberian plate, must be incorrect; 2 The age date show that the earliest magmatic activity began since late-Palaeozoic Permian, which is inconsistent with the previous idea that there were Caledonian and Hercynian active continental margin in the north of North China Craton and in the south Xingkai Massif. 3 the crust and lithosphere were thickened by the subduction and collision of Siberia plate and North China plate during Late Paleozoic. The magma is formed when the crust is heated and melts caused by thickened lithosphere delamination and caused the Asthenosphere upwelling. But only a little basaltic magma erupted, most magma underplate under the bottom of the crust. Thermal energy derived from basaltic magma underplating made the middle and lower crust melt partially and the late Permian-early Triassic granites is formed in large scale.
根据区域构造演化分析,并结合本文及他人高精度同位素年龄,我们对延边花岗岩形成的大地构造环境有了新的认识:1在华北地台北缘并不存在所谓的加里东花岗岩带,因此,建立在此之上的传统的华北地台北缘演化模式及有关西伯利亚板块与华北板块的碰撞拼合的认识也必然是不正确的;2华北地台北缘和兴凯地块南缘不存在加里东期和海西期花岗岩带,表明两地块边缘最早的花岗质岩浆活动始于晚古生代的二叠纪,即不存在传统观点所认为的加里东期或海西期活动陆缘;3晚古生代由于西伯利亚板块与华北板块的俯冲碰撞,致使地壳和岩石圈增厚,导致加厚岩石圈发生拆沉作用,使得软流圈上涌,加热地壳使之熔融形成岩浆,但玄武质岩浆少量喷出地表,大部分底侵于地壳底部,形成下地壳高密度的玄武质底侵层,玄武质岩浆底侵的热能引起中下地壳广泛部分熔融,形成大面积分布的晚二叠世—早三叠世花岗岩。
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Of the five stages deformation, the exact ages of the (2) and (3) were determined by 40Ar/39Ar method as 290 and 259 Ma respectively.2. New results on the metamorphic belts and associated metamorphism of the Xiaopu metamorphic rocksBased on detailed microtextural observations and occurrence of typical metamorphic minerals, five metamorphic belts in the Xiaopu metamorphic rocks are identified. From the north to the south, they are biotite belt, garnet belt, staurolite belt, andalusite belt, and sillimanite belt. I suggested that the metamorphic belts occurred in the Xiaopu area belongs to the high temperature/low pressure series, may have resulted from the later Permian crust extension at ca. 290 Ma.3. I suggest that there may have been a Carboniferous backarc basin along the southern slope of the Harlik Mountain.Detrital Zircon SHRIMP U-Pb dating indicated that the sedimentary age of the Julideneng formation lithic sandstone must be later than late Devonian, most likely is Carboniferous rather than previously thought Precambrian. Analyses on its geologic setting, location of provenance, and sedimentary environment suggest the Carboniferous strata may form in a lagged backarc basin bounded by backarc uplifts.5. Reconstruction of the post-Paleozoic tectonic evolution history of the Harlik MountainThe tectonic evolution of Harlik mountains since the Paleozoic were reconstructed as followings:(1) arc-affinity magmative activities occurred during the middle-Ordovician to early-Silurian;(2) the middle-Silurian to late-Devonian was a back-arc uplift stage;(3) back-arc extension featured the Carboniferous period;(4) post-collisional extension and/then compression during Permian;(5) at the Mesozoic, differential uplift developed; and (6) the late Cenozoic is the intra-continental re-orogen stage.6. Primary estimation of the crust shortening is madeThe folded pre-Mesozoic strata were used to estimate crust shortening along the Harliknanshankou-Koumenzi, Shichengzi-Baishitou, and Qincheng-Xiaopu sections. Their shortening ratios are 16.2%, 19.8%, and 20.1% respectively corresponding crust shortening are 4.3, 9, and 11.3 km.
根据Ar-Ar热年代学研究,精确测定了早二叠世伸展变形和晚二叠世挤压变形的峰期时代分别为290Ma和259Ma.2、提出了关于哈尔里克山南麓小铺一带变质带和变质作用的新认识根据显微观察资料和特征变质矿物的出现,把小铺一带的变质岩由SW向NE方向依次划分为黑云母带、石榴石带、十字石带、红柱石带和矽线石带等变质带;初步确定该区的变质作用属于中温-低压型,变质作用发生的时代为290Ma左右,是该区早二叠世地壳伸展的产物。3、首次提出哈尔里克山南麓在石炭纪可能发育弧后盆地的新观点根据哈尔里克山南麓原&居里得能组&岩屑砂岩的碎屑锆石SHRIMP U-Pb定年,确认这套地层的沉积不早于晚泥盆世,很可能是石炭纪,而不是前人所说的前寒武纪;结合对其区域地质背景、源区位置和沉积环境分析,推测该区石炭纪可能为滞后弧后盆地和弧后隆起区构造背景。4、进一步证明哈尔里克山不发育与岛弧演化相关的泥盆纪岩浆活动根据对代表性闪长岩和花岗岩的锆石SHRIMP年代学研究获得的新资料,结合该区已有相关资料的综合研究,确定哈尔里克山岩浆岩分别形成于奥陶纪-志留纪和石炭纪晚期-二叠纪,不存在泥盆纪的岩浆岩,进而认为该区泥盆纪不属于岛弧环境。5、重建了哈尔里克山古生代以来的地质演化过程根据区域资料以及本次研究所获得的资料,把哈尔里克山古生代以来的构造演化划分中奥陶世-早志留世为岛弧、中志留世-晚泥盆世为弧后区、石炭纪弧后伸展、二叠纪为后碰撞伸展与挤压、中生代差异隆升和晚新生代陆内再造山过程等构造阶段。6、初步估算了哈尔里克山地壳缩短率和缩短量根据前中生代地层褶皱估算的哈尔里克山南山口-口门子、石城子-白石头和沁城-小铺三条剖面的地壳缩短率分别为16.2%、19.8%和20.1%,相应的地壳缩短量分别为4.3km、9km和11.3km。
- 推荐网络例句
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According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.
曝气设备的动力效率在叶轮转速为120rpm~150rpm时取得最大值,此时氧利用率和充氧能力也具有较高值。
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The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.
稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世,形体几无变化。
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When I was in school, the rabbi explained everythingin the Bible two different ways.
当我上学的时候,老师解释《圣经》用两种不同的方法。