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1.
中国中东部沉积盆地在中-新生代的沉积演化   总被引:6,自引:0,他引:6  
王德发  陈建文 《地球科学》1996,21(4):441-448
论述了中国东部沉积盆地在中,新生代各沉积时期的发育特征,沉积相和沉积体系分布,古气候特征,清楚地反映了各沉积盆地的沉积演化和全区范围内的沉积发育过程。  相似文献   

2.
利用测井相分析、岩心观察、粒度及古生物分析等资料,从沉积特征,主要是岩性的纵、横向变化方面,论述了东营凹陷东营组沉积时期沉积体系的发育情况及其分布与演化。认为东营组在上可以划分出冲积扇、河流、三角洲和湖泊4类沉积体系(其中河流沉积体系发育有正常河流沉积体系和辫状河沉积体系,湖泊沉积体系只发育有滨浅湖亚相沉积);在垂向上湖泊沉积体系的分布范围逐渐缩小,河流和三角洲沉积体系的分布范围逐渐扩大,至东营组  相似文献   

3.
根据精细岩相分析,在滇东南泥盆纪台地及台地边缘沉积区识别出9个三级层序,而在深水盆地沉积区仅能识别出3个三级层序。结合海平面波动及构造作用分析,认为在台地或台地边缘沉积区,能划分出的层序在盆地中难以一一对应的原因是:掀斜拉伸作用导致下沉一侧的沉降速度总大于海平面的下降及沉积速率,而保持盆地深水沉积体系的沉积特点或海侵沉积特点,或是以饥饿性盆地性质出现,以致形成的沉积层序相对较少。三级及三级以上(高频沉积层序)沉积层序的形成主要受区域构造作用影响,因构造活动强度的差异而难以进行大区域对比,同一层序界面在不同地区表现出不同的性质。  相似文献   

4.
中国中东部中,新生代盆地分布及沉积体系类型   总被引:3,自引:0,他引:3  
王德发  陈建文 《地球科学》1996,21(4):395-400
中国中东部在中、新生代地震演化中,形成了众多以陆相沉积为主的沉积盆地,可将其分为6大沉积区,其中共发育14类沉积体系,不同的沉积区其发育阶段不同,沉积体系类型和分布亦不同。  相似文献   

5.
嫩江下游现代河流沉积特征   总被引:5,自引:0,他引:5       下载免费PDF全文
王俊玲  任纪舜 《地质论评》2001,47(2):193-199
本文运用河流沉积学原理,以黑龙江省富裕县塔哈乡大马岗嫩江现代沉积露头为例,利用探槽,探坑及钻井获取的野外露头资料及室内各种微观分析测试资料,对嫩江下游现代河流沉积特征进行了详细研究,研究表明,该区河流积积自上而下包括了两种河型沉积,底部是以砾石沉积为主的辫状河沉积,其砾石层厚>5米,横向上可追踪数百米,上部为一低能量曲流河点坝沉积,以中砾质细砂及粉砂沉积为主,底部无明显冲刷面,发育低角度槽状交错层理,同沉积变形层理及波状交错层理,向上过渡为天然堤的粉砂质泥与粉矿薄互层沉积及漫滩粉砂质泥沉积,其整体沉积特征是在一个辫状河泛滥平原上发育起来的低能源曲流河沉积,这一研究为地下复杂的河流相地层识 提供了一个新的实例。  相似文献   

6.
河流深槽沉积体是河流沉积的一种特殊沉积体。辽河坳陷第三纪断裂活动强烈,火山岩广泛分布,形成了独特的地貌条件,具备形成河流深槽沉积体的地质条件。本文以辽河坳陷东部凹陷大25井区为例,对河流深槽沉积体的成因及特征进行探讨,证实了大25井区巨厚砂砾岩沉积是河流在火山岩古地形的限制下发生急转弯,在其变曲河段的深槽中沉积的深槽沉积体。该沉积体中发育良好的储集空间,有利于油气储集。该类储集体的发现,丰富了辽河坳陷的储层类型,为油气勘探提供了新的领域。  相似文献   

7.
南秦岭泥盆纪海底热液沉积的野外和野内研究使我们认识到:泥盆纪同生海底絷宙积作用在泥盆系沉积柱中形成了多种类型的层状岩石和矿石;作为沉积柱中不可分割的一部分,海底热液沉积有其自身的特点,可识别并用于指导找矿;沉积柱中不同层位多种热液沉积构成海底热液沉积记录,海底热液沉积成矿作用是这种热演化达到一定阶段的结果,海底热液沉积的内涵是壳内释热以流体形式在达地表或近地表所发生的以化学沉积作用为主,并伴有交代  相似文献   

8.
陈振岩  李军生 《沉积学报》1996,14(3):157-161
河流深槽沉积体是河流沉积的一种特殊沉积体。辽河坳陷第三纪断裂活动强烈,火山岩广泛分布,形成了独特的地貌条件,具备形成河流深槽沉积体的地质条件。本文以辽河坳陷东部凹陷大25井区为例,对河流深槽沉积体的成因及特征进行探讨,证实了大25井区巨厚砂砾岩沉积是河流在火山岩古地形的限制下发生急转弯,在其变曲河段的深槽中沉积的深槽沉积体。该沉积体中发育良好的储集空间,有利于油气储集。该类储集体的发现,丰富了辽河坳陷的储层类型,为油气勘探提供了新的领域。  相似文献   

9.
陆源碎屑与碳酸盐混合沉积研究中的几点思考   总被引:11,自引:0,他引:11  
在前人研究的基础上,结合一些具体研究实例,对混合沉积的定义进行了修正和补充;对混积岩和混积层系重新进行分类和命名;根据混合沉积的定义、成因、成分、结构、沉积构造及接触关系等因素,按照“沉积事件+剖面结构”的原则,提出了渐变式、突变式和复合式3种成因类型,对前人的研究成果进行了概括和归纳;对混合沉积的控制因素进行了深入讨论;在以碳酸盐沉积为主和以陆源碎屑沉积为主的2类沉积背景下详细论述了层序格架中混合沉积的发育情况;结合混合沉积本身的特点讨论了混合沉积与油气的关系。最后针对混合沉积研究现状,指出了该领域研究中存在的问题,并对未来的研究方向进行了展望。  相似文献   

10.
本文根据杭州湾沿海平原大量的钻井、静力触探井和分析化验等资料,研究了下切河谷(钱塘江和太湖下切河谷)充填物的沉积建造和沉积相,以及浅层生物气藏分布特征。研究表明,末次冰期以来,随着海平面变化,杭州湾地区下切河谷演化经历了深切、快速充填和埋藏三个阶段。末次冰盛期,海平面下降的幅度大,增加了河流梯度、加强了下切作用,本区形成了钱塘江和太湖下切河谷,随后在冰后期被充填和埋藏,下切河谷的两侧为暴露地表的古河间地。根据岩石学、沉积结构和沉积构造特征,本区下切河谷充填沉积物表现为向上变细的沉积层序,可以划分为4个沉积相类型,有河床滞留沉积物到部分曲流河沉积体系的边滩沉积、河漫滩-河口湾沉积、河口湾-浅海沉积和河口湾沙坝沉积。在河漫滩-河口湾相沉积期间,由于海平面上升、潮流体系、沉积物供给和可容空间条件适合一个潮流沙脊体系的发育,该相中砂质透镜体可能代表下切河谷内发育的潮流沙脊。对于河口湾-浅海沉积和河口湾沙坝沉积而言,由于沉积条件不再有利,没有形成沙脊沉积。所有的商业性生物气都存储在下切河谷内河漫滩-河口湾砂质透镜体中。  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

13.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

14.
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931.  相似文献   

15.
PALEONTOLOGY     
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.)  相似文献   

16.
正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.)  相似文献   

17.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.)  相似文献   

18.
PETROLOGY     
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus.,  相似文献   

19.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an  相似文献   

20.
正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of  相似文献   

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