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1.
Kevin Burke 《Tectonophysics》1976,36(1-3)
Well over one hundred separate graben formed in association with ocean opening can be recognized around the shores of the Atlantic Ocean. The graben are linked forming an elaborate network of triple-rift systems. Some rifts developed to form ocean but many failed. The stratigraphie and structural history of these rift structures is varied and helps to illuminate the processes that operate at continental rupture. Rifting has been commonly accompanied by basaltic vulcanism and rapid accumulation of several kilometers of sediment. Horsts within the graben strongly influence early sediment distribution. Generally, rift faulting ceases about the time of onset of normal marine sedimentation but there are a few exceptions and some graben formed at ocean opening have influenced sediment distribution more than 100 m.y. later. Although tensional structures predominate strike-slip and compressional structures have developed locally in the graben. The rivers bringing the largest amounts of sediment into the Atlantic during the last 150 m.y. have prograded along failed rift arms formed at continental rupture. In some cases their deltas have come to lie on oceanic crust. 相似文献
2.
Many continental basins were formed when the most of the South Mongolian territoty is modulated to continents from Late Carboniferous (Tectonic map of Mongolia, 1978). One of these basins is Noyon-Gurvantes continental sedimentary basin (NGCB). (Fig. 1)
NGCB comprises on the territory Gurvantes and Noyon sums of Umnugovi aimag (province), which are Noyon mountain range, its mountain side, foot of the mountain, Nariinsukhait and Argun hills geographically. The purpose of our study was to determine the geological age of coal bearing sediments of the coal mines near or at Nariin Sukhait, and to study their structure and moreover enhance the chance to discover new deposits. 相似文献
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西藏许如错地区在国内鲜有学者研究,仅在少有的区域地质报告中出现。研究区内发育一套古近系碎屑岩沉积——日贡拉组,该地层在研究区局部具有一套火山岩夹层。文章通过对许如错地区古近系日贡拉组碎屑锆石的LA-ICP-MS U-Pb测年分析,结合周边盆地年龄结构及研究区沉积现象,进而追寻盆地沉积物物源和盆地充填记录。研究表明,日贡拉组为一套由粗变细最终又变粗的碎屑岩沉积夹少量火山岩,根据沉积原生构造和宏观剖面判断其主要是扇三角洲-浅湖相-扇三角洲的沉积环境;岩浆成因的碎屑锆石年龄峰值集中在127～134 Ma年龄段内,结合周缘年龄推断日贡拉组物源来自北—北西中部拉萨地块的早白垩世花岗岩。通过对研究区日贡拉组岩石组合、岩石地层序列、物源分析、沉积演化过程以及年代证据等方面的研究,发现日贡拉组的发育处于青藏高原俯冲碰撞隆升阶段和汇聚挤压隆升阶段。 相似文献
6.
东海盆地中、新生代盆架结构与构造演化 总被引：6，自引：0，他引：6
基于地貌、钻井、岩石测年和地震等资料,分析盆地地层分布、盆架结构、构造单元划分和裂陷迁移规律,结果表明东海盆地由台北坳陷、舟山隆起、浙东坳陷、钓鱼岛隆褶带和冲绳坳陷构成,是以新生代沉积为主、中生代沉积为辅的大型中、新生代叠合含油气盆地;古元古代变质岩系构成了盆地的基底。该盆地不仅是印度-太平洋前后相继的动力体系作用下形成的西太平洋沟-弧-盆构造体系域一部分,而且也是古亚洲洋动力体系作用下形成的古亚洲洋构造域和特提斯洋动力体系作用下形成的特提斯洋构造域一部分,晚侏罗世至早白垩世经历了构造体制转换,盆地格局发生重大变革,早白垩世以前主要受古亚洲-特提斯洋构造体制影响的强烈挤压造山和地壳增厚作用演变为早白垩世以来主要受太平洋构造体制控制的陆缘伸展裂陷和岩石圈减薄作用,经历侏罗纪古亚洲-特提斯构造体制大陆边缘拗陷和白垩纪以来太平洋构造体制弧后裂陷两大演化阶段。白垩纪以来太平洋构造体制的弧后裂陷演化阶段可细分为早白垩世至始新世裂陷期、渐新世至晚中新世拗陷期和中新世末至全新世裂陷期。 相似文献
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通过楚雄盆地与四川盆地中西部区域地质条件和油气地质条件的对比研究,探讨了楚雄盆地与四川盆地中西部地区盆地性质、沉积序列、油气地质条件等方面的异同点,从而给楚雄盆地的油气勘探一些启示：它们间的基本地质特征、油气地质特征类似,且上三叠统地层为主要的烃源岩和自生自储组合,侏罗系储层也具有低孔、低渗、高含水饱和度、非均质性强的特征,裂缝对油气的富集、高产起到了重要作用。认为：加强砂体的展布、连通性研究,裂缝、断层性质、形态、沟通性、规模等研究,在有白垩系、第三系覆盖区完全有可能进行油气勘探。 相似文献
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桂西南晚古生代深水相地层序列及沉积演化 总被引：10，自引：0，他引：10
右江盆地晚古生代沉积由浅水陆棚、地台边缘—斜坡、孤立碳酸盐岩台地和深水盆地4种主要的沉积类型组成,自北向南呈现由浅到深的规律性分布。深水区地层以含锰粘土岩、硅质岩、滑塌角砾灰岩和普遍发育玄武岩为重要特征,与盆地边缘差别显著。以斜坡相区生物地层控制良好的层序地层和重要事件为桥梁,建立了深水区地层序列、主要的海平面变化旋回及其与不同相区的年代地层对比关系。深水区岩浆活动可识别D1晚期—D2早期、D3晚期—C1早期、C2中期—P1早期以及P3—T1早期4个幕式活跃期;以洋岛型玄武岩(OIB)为主,滇—桂—越边境地区具洋岛—洋脊型(MORB)过渡特征。枕状玄武岩主要集中在C1早期、C2中期—P1早期和T1早期三个时段,其中C2—P1玄武岩厚度最大、分布最广。研究表明右江盆地是晚古生代发育于扬子与印支地块间的小洋盆,属东特提斯多岛洋的一部分。其沉积演化经历了浅水陆表海盆地(D1)、深水裂谷盆地(D2—D3)、扩张洋盆(C1—P2)、收缩洋盆(P3—T2早期)、残余盆地(T2晚期—T3早期)五个阶段。盆地西南缘可能属印支地块的北部边缘,而盆地北部属扬子地块的西南缘。 相似文献
9.
为了发挥油气化探“迅速掌握全局快速缩小靶区”的战略性作用，服务油气化探全国扫面计划，选择塔里木含油气盆地北部开展低密度（1点/25km2）油气地球化学填图试点。油气化探填图指标土壤酸解烃、顶空气轻烃、荧光光谱、紫外吸收光谱和蚀变碳酸盐在大型油气田、油气富集区带上方均发育地球化学省异常，异常平面空间分布与地下油气富集区带具有良好的套合关系，对油气富集具有指示意义。区域性的荧光光谱等指标异常浓集中心沿轮台断裂等主干断裂带分布，与地下断裂位置良好的匹配性指示了油气大规模的运聚。甲烷碳同位素证实研究区油气地球化学省异常成因为热解成因，土壤样品三维荧光光谱发育共性峰，三维荧光光谱指纹特征反映了近地表土壤烃类异常与地下油气运移和油气藏类型相关。塔里木盆地北部地区油气地球化学填图试点结果表明，大型盆地可以采用甚低密度油气地球化学填图技术，圈出寻找大、中型油气田和油气富集区带的异常区，发挥油气化探“迅速掌握全局快速缩小靶区”的战略性作用。 相似文献
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Acta Geochimica - Surface radioactive survey has been carried with portable gamma ray spectrometer (PGRS) about the 45 km2 around the Srisailam sub basin, the surface radioactive anomalies... 相似文献
11.
The Ruhr coal basin is part of the external fold and thrust belt of the Variscan orogen in Central Europe. Information from extensive coal mining, outcrops in the south of the Ruhr district, reflection seismic surveys and about 800 exploration boreholes in the north, support the interpretation of a mostly molasse-type sequence, more than 6000 m thick, of Namurian and Westphalian age. Both the southwest-northeast trending sedimentary basin structures and the fold structures of the Ruhr Carboniferous were caused by the compressive regime of the Variscan folding in its hinterland, but there is no direct relationship between sedimentary basin structures and the later folding structures. Coal formation started in the Namurian C, reached its maximum during the Westphalian A and B and ended during the Westphalian D. In total, about 250 coal seams were formed, but only 50 of them are of economic importance at present.Strata thicknesses and coal content are generally greater in the southeast of the Ruhr coalfield than in the northwest. An important exception can be observed in the lower part of the Westphalian A, where, in contrast, strata thicknesses are greatest in the northwest (in the Münsterland region), although the coal content remains the greatest in the southeast.Detailed isopach maps covering 100–200 m thick stratigraphic intervals reveal the existence of a southwest-northeast trending zone of reduced subsidence in the Ruhr coalfield that moved from southwest-northeast during the Westphalian. This structure can be interpreted as a peripheral bulge. Coal seems are purer and thicker in the area of this structure, which therefore must have been a paleogeographic element within the Ruhr basin.The general effect of a general decrease in the coal content of the Upper Carboniferous towards the northwest is superimposed on the migration of the coal content maxima of individual formations towards the northwest. During the Namurian C and Westphalian A the coal content maxima were situated in the area of the River Ruhr and during the Westphalian B and C in the area of the River Lippe.The deformation of the Ruhr coal basin is of post-Westphalian age, as demonstrated by the concordant folding of the Devonian and Carboniferous strata. The tectonic structure is mainly characterised by the following elements: stockwerk tectonics, axial elevations and a succession of compressional and extensional tectonics.Due to the general dip of the Ruhr coal basin towards the north, different structural levels (“stockwerks”) can be observed. The southern area displays the lowermost stockwerk, with many minor folds of about constant wavelength and low amplitudes. Thrusts are mainly small and some of them show increasing displacement upwards. The central part of the mining area displays the intermediate stockwerk with large, tight anticlinoria with minor folds separated by open synclines. These are accompanied by folded northwest- and southeast-vergent thrusts. In the northern Ruhr district, high anticlines and broad, trough-shaped synclinoria with only few thrusts represent the uppermost stockwerk. Large fold controlled thrusts die out at this level. Axial culminations and depressions have strongly influenced the structural style of the folding as well.According to this model of stockwerk tectonics, excess volume created by disharmonic folding is redistributed by thrusts. Thrusts dying out downwards at different stratigraphic and structural levels give evidence that there is no regional basal detachment below the Ruhr coal basin. This interpretation fits very well to new results achieved by the deep seismic reflection profile DEKORP 2-N. The section clearly shows thick-skinned tectonics in the Rhenish massif, with a shortening of the whole thickness of crust. The Ruhr coal basin can, therefore, be interpreted in terms of an autochthonous foreland basin in front of a buried thrust front to the south.Investigations on the post-Carboniferous strata of the Ruhr basin indicate different periods of active faulting. Cross and diagonal faults were formed partly at the end of the Variscan folding and partly before and during deposition of the Zechstein strata. A further important period of tectonic movements occurred during the early Kimmerian phase in the Late Triassic. Furthermore, earlier extensional faults in the Ruhr basin have been affected by Late Cretaceous transpression. 相似文献
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以松辽盆地和桦甸盆地为例,对盆地中富有机质泥岩进行系统测试。分析表明,富有机质泥岩中含油率和TOC、气体损失率呈明显的正相关; 而与半焦、密度呈负相关; 与全水的相关性不明显。结合相关研究表明,松辽盆地富有机质泥岩中有机质主要来自湖泊自身生产物,沉积速率较慢,且成岩作用相对较强,此盆地油页岩适合低温干馏炼油,因干馏后半焦中残留有机质较少,适合烧砖、制作水泥等。桦甸盆地油页岩有机质为湖泊生物和陆源有机质共同来源,沉积速率相对较快,成岩作用较弱,此盆地油页岩适合低温干馏炼油,干馏后半焦中残留有机质较多,适合发电和烧砖等,损失气体可以回收进行瓦斯发电。 相似文献
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Ernst Antevs 《International Journal of Earth Sciences》1952,40(1):94-108
The Great Basin in the western United States consists of almost level desert basins and alternating parallel mountain ranges. It has sparse, mostly interior, drainage and a few permanent lakes. The climate is arid and semiarid. Fairly large areas are true deserts. The main Cenozoic climatic changes have been: 1. a general cooling during the Tertiary and the early Pleistocene, 2. a progressive drying from the early Miocene into the Pleistocene as a consequence of rise of the Sierra Nevada and the Cascades, and 3. Pleistocene fluctuations between cold-moist and warm-dry ages.The Ice Age left known records of three or four major glaciations, the last of which had two maxima. The glaciations were relatively extensive on the eastern flank of the Sierra Nevada and just east of the Great Basin, and glaciers existed on several ranges in northeastern Nevada. Each glacial was accompanied by a pluvial, which culminated just after the glacial maximum. The pluvial lakes were largest on Lat. 40°. The histories of the huge lakes Bonneville and Lahontan are incompletely known. During the Mankato-Tioga-Provo'glacio-pluvial maximum the temperature in the Great Basin seems to have been only 2.5–3 C° lower, and the precipitation on the surface of Lake Lahontan (Dendritic Lake) twice as large as now.The Neothermal (Postglacial, Postpluvial), the equivalent of the interglacials, is with long-distance correlation in view subdivided on the basis of the major temperature changes into the Ana-,.Alti-, and Medithermal ages. However, in the dry country of the Great Basin the changes in moisture are more apparent and important. The Altithermal was distinctly drier than the present, and nearly all the basins went dry. About 2000 B.C. several basins began again to contain lakes which remained permanent through some acute brief droughts. These recentmodern lakes attained very moderate maxima some time before Christ, while the glaciers in the adjacent mountains probably reached their greatest extent since the Anathermal during the last centuries. 相似文献
14.
Depositional evolution of the Bowen basin 总被引：1，自引：1，他引：0
E. J. Malone 《Australian Journal of Earth Sciences》2013,60(2):263-282
The Bowen Basin is a structurally complex area occupied by a thick sequence of Permian‐Triassic volcanics and sediments whose depositional history is also complex and in many places has controlled the subsequent structural development. The depositional evolution is portrayed by isopach maps of eight regional rock units recognised in the Bowen Basin sequence. This sequence was deposited in a series of downwarps and on adjacent, less rapidly subsiding shelf areas. This paper discusses the shape, distribution, and persistence in time of the downwarps and shelf areas and indicates the relationship between them and the present structural elements of the Bowen Basin. The relationship of the depositional history of the Bowen Basin to the problems of exploration for oil and gas in the Basin is also discussed. 相似文献
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《International Geology Review》2012,54(2):197-212
The article considers the mineral and chemical composition of ores of the Kerch' basin; the mode of occurrence of Fe, Mn, P, Si, Al, Ca, Mg, S and Corg in them; and the mechanisms of their deposition. — Author. 相似文献
17.
Antonio Herrero Gaspar Alonso-Gavilán Juan Ramón Colmenero 《Sedimentary Geology》2010,223(3-4):235-264
The Cenozoic record of the north-western domain of the Duero basin is articulated at the surface through a set of continental depositional sequences called, from base to top, the Vegaquemada sequence, the Candanedo sequence, and the Barrillos sequence. These depositional sequences were deposited in continental sedimentary environments. The deposition of the first sequence occurred through a fluvial system with floodplains cut by low-sinuosity channels. The Vegaquemada sequence was developed between the Middle Eocene and the Early Agenian. The second sequence was formed by a set of highly efficient transport alluvial fans that evolved laterally towards fluvial systems with low-sinuosity fluvial channels and an extensive floodplain, where several types of palaeosols were formed. This sequence developed between the Early Agenian and the Late Vallesian. The third unit–the Barrillos sequence (between the Late Vallesian and the Turolian/Ruscinian transition), was generated by a set of highly efficient transport alluvial fans dominated by low-sinuosity fluvial channels.In subsurface geology, seismic and well data are used to rebuild the stratigraphic architecture. The two basal depositional sequences can be identified with two seismic units: the Palaeogene Seismic Unit (PgSU) and the Neogene Seismic Unit (NgSU), respectively. In the present work, we obtained the isovelocity, isochron, and isobath maps for the top and base of the two Cenozoic units. The Palaeozoic (PzSU) and Mesozoic (MzSU) seismic units are found under these two units. Through study of the logs of the various boreholes, it was only possible to analyse the upper 700 m of the Candanedo Sequence (NgSU), without encompassing the total thickness of the unit. Several middle-order sequences were differentiated, in general showing a sequential fining-upwards evolutionary character. Additionally, for the boreholes analysed two main types of electrofacies were identified, both representing fluvial channels and floodplain deposits.The north-western domain of the Duero basin is interpreted to have been formed in response to the tectonic uplifting of the Cantabrian Mountains since Middle-Eocene times. Integration of the data concerning the surface and subsurface geology in this domain reveals that this basin edge behaved as a foreland basin during Cenozoic stages. The foredeep, with a depth of 2800 m, is oriented east–west and has a sediment thickness of up to 3500 m. The forebulge is located in the southwestern zone and represents an area of basement uplifting in which a minimum thickness of materials from the Cenozoic depositional sequences has accumulated. 相似文献
18.
Quantitative models of sedimentary basin filling 总被引：1，自引：0，他引：1
Chris Paola 《Sedimentology》2000,47(Z1):121-178
Quantitative modelling of the filling of sedimentary basins was begun in earnest in the 1960s. Dozens of themes and variations have been proposed since then, and have yielded an abundance of idealized stratigraphic patterns as functions of both imposed changes and basin properties. Post‐plate‐tectonic modelling began with ‘rigid‐lid' models, which show the stratigraphic signature of subsidence variation. This work introduced the connection between stratigraphy and the rheology of the lithosphere. Rigid‐lid models are the simplest type of geometric model, in which the sediment surface is assigned prescribed geometries, usually corresponding to different depositional environments. These can reproduce many aspects of overall stratal geometry but are formally restricted to relatively long timescales, for which quasi‐steady surface topography can be assumed. So‐called dynamic models attempt to represent the morphodynamics of the sediment surface by abstracting and averaging short‐term transport processes. Most of the dynamic models proposed to date can be seen as special cases of a single general morpho‐dynamic equation. The most important result of the first wave of quantitative basin‐filling models is that even relatively simple models can produce reasonable stratal patterns. We now have a wide array of tools for exploring scenarios, searching for general behaviours and effects, and making initial quantitative predictions. We have also learned that basin response to external forcing as recorded in stratigraphy can be as sensitive to the characteristics of the basin as to the forcing. The main brake on the development of basin modelling is not computing power but lack of methods and data for testing the models we have already developed. Physical experiments, which are only just beginning, are one means of doing this. Experimental stratigraphy is a bridge to quantitative field tests, which will require collaboration among academic researchers from a wide range of areas, and between academia and industry, on projects of greater scale and degree of integration than we have seen so far. The advancement of quantitative sedimentary geology will also require significant changes in the way the subject is taught, at all levels. 相似文献
19.
Finite-element modelling of pull-apart basin formation 总被引：1，自引：0，他引：1
We present the results of a finite-element modelling study of pull-apart basin formation related to left-stepping left lateral strike-slip faults. The modelling quantifies the relationship between fault geometry (i.e., fault overlap and separation) and pull-apart basin formation. Two depocentres (subbasins) separated by a broad zone of relative uplift in between may develop if the strike-slip domain is characterized by fault underlap. For overlapping faults migration of the subbasins is predicted by the models. Deep subbasins in a large area of subsidence which spans the entire inner fault zone may form if fault overlap is about three times the fault separation.
The models suggest that a topographic asymmetry within the fault zone may arise due to a different displacement ratio of the strike-slip faults. The modelling results show that this asymmetry in topography becomes more pronounced towards the more active fault. Thus, basin deepening occurs progressively towards the fault characterized by the largest amount of lateral displacement. Moreover, the results indicate that the smaller the fault separation (less than basin length) the less pronounced the topographic asymmetry.
The models provide quantitative estimates for the effects of changes in elastic material properties, the magnitude of the compressive far-field stress and the coefficient of friction of the faults on the resulting topography.
Comparison of the modelling results with field observations from the Cerro Blanco-El Barranquete (CBB) subbasin located in the Internal Zone of the Betic Cordillera, southeastern Spain support an interpretation in which the interplay of major faults has formed the CBB subbasin. 相似文献
20.
陆内裂陷盆地区形成和演化过程中的构造力包括4方面：（1）地幔对流由岩石圈板块底面边界施加到岩石圈板块内部的构造力F1;（2）板块相对运动通过岩石圈板块侧面边界施加到岩石圈板块内部的构造力F2;（3）岩石圈受热膨胀和冷却收缩在地壳内部产生的构造力F3;（4）地壳质量在地壳内部产生的围压F4。地壳中的应力是这4方面的构造力的函数S(Fi),其中,F1和 F2的大小和方向对三轴应力状态的主应力大小和方向起决定作用。地壳发育正断层的条件是应力状态方程S（Fi）中σ2 σ3主应力平面大致处于水平面状态、σ1近直立。当F1和F2的方向一致且F1＞F2或F1和F2的作用方向相互垂直的情况下,F1和F2合成的应力场中的最小主应力方向与X轴方向一致,地壳发生正向裂陷作用。在F1和F2的方向既不平行也不垂直的情况下, F1和F2叠加产生最小主应力（σ3）的方向与X轴方向不一致,地壳发生斜向裂陷作用。当地幔对流从岩石圈底部对岩石圈产生的引张作用力减小、板块之间相对运动从岩石圈侧面边界对岩石圈产生的挤压作用力增强的情形下,地壳应力状态S（Fi）在X轴和Y轴构成的水平面上的最大主应力可能超过Z轴方向的主应力,使σZ相当于三轴应力状态的σ2,裂陷盆地发生走滑构造变形。如果地壳应力状态S（Fi）在X轴和Y轴构成的水平面上的最小主应力也超过Z轴方向的主应力,则σZ相当于三轴应力状态的σ3,裂陷盆地发生收缩构造变形,可能发育逆冲断层或使早期的正断层发生反转位移。随着裂陷作用的渐进发展,不同时期F1和F2的大小和方向的变化导致地壳应力场的主应力轴方向也相应发生变化,使裂陷盆地在不同演化阶段表现出不同的构造变形特征。 相似文献