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1.
前陆、前陆盆地和前陆盆地系统   总被引:7,自引:1,他引:7  
前陆是指与造山带相毗连的构造相对稳定地区,造山带的岩石向着它俯冲成掩覆,可分为三种类型,即曾为被动型大陆边缘的(Ⅰ型),曾与沟-弧系有关的(Ⅱ型)和陆内造山带前方的(Ⅲ型)。前陆盆地为沿造山带前陆区分布的线状压性深坳陷,可分为周缘前陆盆地,弧后前陆盆地和陆内前陆盆地三种类型。前陆盆地系统是一个沿造山带分布的长条状的潜在沉积可容空间,可划分为楔顶,前渊,前隆和隆后等4个部分。  相似文献   

2.
边缘海盆地的形成机制及其对中国东南地质研究的启示   总被引:11,自引:0,他引:11  
虽然有关边缘海的成因解释有“捕获机制”、弧后扩张(被动、主动)机制、陆内应力传播机制等,但迄今尚未有一种机制能统一解释所有边缘海的成因。边缘
海的成因不仅是经典的沟-弧-盆二维剖面问题,而应是一个包括平面图上大陆板块的变形在内的三维问题。边缘海的研究能给我国东部、特别是东南地区地质研究提供有益的启示,它包括:慎重鉴别古岛弧、对变质带、古洋壳及洋盆规模;充分注意小块体之间的碰撞,古转换断层在本区晚中生代岩浆活动、大陆增生过程中起重要作用;相关盆地内的沉积物记录着丰富的大陆碰撞、造山作用的信息。  相似文献   

3.
中国中西部广泛发育中新生代类前陆盆地,其地质结构和石油地质条件等方面与典型前陆盆地既有类似之处也存在明显差异,主要表现在演化历史复杂;石炭纪以前均为构造性质各异的海相盆地,二叠纪为海相盆地向陆向盆地的转换过渡时期,三叠纪以后基本为陆相盆地(仅塔里木西南盆地晚白垩世-早第三纪有短暂海侵),侏罗纪-白垩纪为断陷-坳陷盆地西部),第三纪以后,逐渐转变为类前陆盆地(西部),在生烃条件方面不仅发育海相烃源岩,且普遍存在煤系烃源岩,进一步增加了其生烃潜力,同样,在储集条件方面,中国类前陆盆地除发育海相储集层外,还广泛分布陆相储集层,因此,中国类前陆盆地基本石油地质条件与国外富油气前陆盆地相比,除海相烃源岩的质量不及后者外,其它方面并无明显不足,且具有发育陆相烃源岩和储集岩的优势,因此,中国中西部类前陆盆地具有较好的勘探前景,特别是陆相层序具有更为现实的勘探价值。  相似文献   

4.
研究表明,本区现阶段的构造分区为:天山地洼区,准噶尔地洼区和阿尔泰地洼区,各区演化、发展各具特征,表明地壳演比的不平衡性和差异性,石炭—二叠纪分别处于地槽发展前期和后期,二者无论在沉积环境、古地理条件,还是在构造型式、岩浆活动强度上都存在明显的差异。前期形成的聚煤盆地属海相环境,受近东西、北西西向地槽构造系的控制,火山话动强烈,系典型的优地槽沉积;后期形成的聚煤盆地属海陆交替相、陆相环境,为山间坳陷型盆地,受地槽褶皱山系的控制,以快速升降运动和快速堆积为特色,盆地中沉积了巨厚的磨拉式建造。石炭—二叠纪的沉积环境和构造条件不利于聚煤作用的发生和持续进行,致使海盆边缘和陆盆中未能形成良好的含煤岩系。因此,新疆北部地槽区与华北地合区相反,石炭—二叠纪不是理想的成煤时期,地槽期的海盆和地槽褶皱带期的山间坳陷也不是理想的聚煤盆地,这为该区的大地构造条件所决定。  相似文献   

5.
Deepwater oil and gas exploration has become a global hotspot in recent years and the study of the deep waters of marginal seas is an important frontier research area.The South China Sea(SCS)is a typical marginal sea that includes Paleo SCS and New SCS tectonic cycles.The latter includes continental marginal rifting,intercontinental oceanic expansion and oceanic shrinking,which controlled the evolution of basins,and the generation,migration and accumulation of hydrocarbons in the deepwater basins on the continental margin of the northern SCS.In the Paleogene,the basins rifted along the margin of the continent and were filled mainly with sediments in marine-continental transitional environments.In the Neogene–Quaternary,due to thermal subsidence,neritic-abyssal facies sediments from the passive continental margin of the SCS mainly filled the basins.The source rocks include mainly Oligocene coal-bearing deltaic and marine mudstones,which were heated by multiple events with high geothermal temperature and terrestrial heat flow,resulting in the generation of gas and oil.The faults,diapirs and sandstones controlled the migration of hydrocarbons that accumulated principally in a large canyon channel,a continental deepwater fan,and a shelf-margin delta.  相似文献   

6.
西北侏罗纪陆相盆地低煤级煤层气藏勘探开发近年来受到越来越多的关注,煤层气成藏机制是该区煤层气勘探开发的重要基础工作,而煤层气储集是煤层气成藏的关键地质过程。研究表明:准噶尔、土哈两个侏罗纪陆相盆地低煤级煤储层具有高孔容、高孔比表面积、高游离气储集潜力和低原位吸附气体能力的特征,深部煤储层储集气量显著高于浅部煤储层;浅部煤储层中基本上为吸附气,深部煤储层中吸附气、游离气、溶解气共存,游离气的重要性随埋深增加而增大;构造高点和构造圈闭对深部煤层气成藏具有重大影响,煤层气与常规气兼探与共采在理论上可行,深部煤层气藏可能较浅部煤层气藏更具开发价值。  相似文献   

7.
准噶尔和吐哈盆地侏罗系煤层气储集特征   总被引:7,自引:0,他引:7  
西北侏罗纪陆相盆地低煤级煤层气藏勘探开发近年来受到越来越多的关注,煤层气成藏机制是该区煤层气勘探开发的重要基础工作,而煤层气储集是煤层气成藏的关键地质过程。研究表明:准噶尔、土哈两个侏罗纪陆相盆地低煤级煤储层具有高孔容、高孔比表面积、高游离气储集潜力和低原位吸附气体能力的特征,深部煤储层储集气量显著高于浅部煤储层;浅部煤储层中基本上为吸附气,深部煤储层中吸附气、游离气、溶解气共存,游离气的重要性随埋深增加而增大;构造高点和构造圈闭对深部煤层气成藏具有重大影响,煤层气与常规气兼探与共采在理论上可行。深部煤层气藏可能较浅部煤层气藏更具开发价值。  相似文献   

8.
The coal-forming characteristics,as well as the similarities and differences between epicontinental sea basins and continental marginal sea basins developed during different time periods,were analyzed in this study by adopting comparative analysis thoughts and methods.The results obtained in this study revealed that epicontinental basins and marginal sea basins are both characterized by the main development of thin coal seams or extremely thin coal seams.In addition,changes in sea levels were determined to be the main controlling factors for coal formation,and there were similarities in the continent-sea interactions and coal-forming sedimentary systems of the different basins.However,there were also significant differences observed in the sea level change events,basin basement structural characteristics,coal seam stability levels,accumulation and aggregation characteristics,and the migration patterns of coal-forming materials.For example,the marginal sea basins in the South China Sea were found to be characterized by strong tectonic activities,diversity and complexity.The basin structures showed complex patterns of depressions,uplifts and concave or sag uplifts,which tended to lead to greater complexity in the paleogeographic patterns of the coal formations.This had subsequently resulted in complex coal-forming processes and paleogeographic characteristics,in which the coal-forming zones displayed bead-like distributions,and the enrichment areas and centers were scattered.The practical significance of studying the similarities and differences of the coal-forming characteristics between epicontinental basins and marginal sea basins is that the results can potentially be used to guide the predictions of coal-measure coal seam distributions in South China Sea,as well as provide valuable guidance for future explorations of natural gas reservoirs related to coal measures in the South China Sea area.  相似文献   

9.
盆地-山岭耦合体系与地球动力学机制   总被引:40,自引:1,他引:39  
刘和甫 《地球科学》2001,26(6):581-596
盆山耦合分析应该将地球动力学环境和板块运动学序列结合起来, 根据地球动力学环境所提出的: 伸展构造体系、挤压构造体系、走滑构造体系和克拉通构造体系进行定性与定量分析; 依照板块运动学序列所划分的主要旋回: 裂解阶段、俯冲阶段、碰撞阶段和后造山阶段进行定位与定时分析.伸展构造体系在离散期为陆内裂陷盆地及伸展造山带; 在聚合期为弧后裂陷盆地及张性岩浆弧造山带; 在后造山期为后继裂陷盆地及晚期伸展造山带.挤压构造体系在俯冲期为弧后前陆盆地及俯冲造山带; 在碰撞期为周缘前陆盆地及碰撞造山带; 在再活动期为再生前陆盆地及再生造山带.走滑构造体系在伸展期为走滑拉分盆地及剪张山岭; 在挤压期为走滑挠曲盆地及剪压造山带.克拉通构造体系在裂解期为克拉通内部盆地; 在拼合期为克拉通边缘盆地.   相似文献   

10.
Cenozoic continental rifting in southern East Siberia and northern Mongolia has been associated with subsidence and broadening of rift basins at the account of their mountain borders. This neotectonic trend is, however, superposed with continuous or periodic tectonic inversions in which the basin floor may uplift while marginal fault steps and saddles between basins may subside. Cenozoic geomorphic inversions are expressed in changes of river flow out of Lake Baikal.  相似文献   

11.
论沉积盆地的等时地层格架和基本建造单元   总被引:45,自引:4,他引:45  
层序地层分析为当代沉积学的重大进展领域和研究热点,主要来自北美边缘海盆地的经验不能简单的用于性质极不相同的、在我国占重要比例的内陆盆地和近海盆地。为此本文从更广泛意义上讨论了层序地层单元和各级建造块的地质涵意,并以在我国不同类型板内盆地中的实践进行了论证,提出了在我国进一步开展层序地层分析的主要问题。  相似文献   

12.
盆山耦合与前陆盆地成藏区带分析   总被引:9,自引:2,他引:9  
经济全球化导致油气勘探全球化,板块学说在理论上提供全球油气勘探基础,亚洲大陆与北美大陆盆山体系在实践上提供全球油气勘探经验。盆山耦合体系存在3类造山带与3类前陆盆地即:(1)俯冲造山带与弧后前陆盆地;(2)碰撞造山带与周缘前陆盆地;(3)陆内造山带与陆内前陆盆地。前陆盆地成藏区带勘探中,在空间上应将造山带前麓褶皱—冲断带层与前陆盆地作为统一应变场,在时间上应将前冲断作用沉积层序,同冲断作用沉积层序和后冲断作用沉积层序作为整体来进行勘探。  相似文献   

13.
PALAEOSHORELINES AS INDICATOR OF LATE CENOZOIC CLIMO-TECTONIC CHANGES IN LADAKH TRANS HIMALAYA:AN ILLUSTRATION FROM TSO KAR LAKE1 BhattacharyyaA .Vegetationandclimateduringthelast 30 0 0 0 yearsinLadakh [J] .Palaeogeogr,Palaeoclimatol,Palaeoecol,1989,73:2 5~ 38. 2 CerlingTE .LateCenozoicvegetationchange,atmosphericCO2 andtectonics[A] .Ruddiman ,W .F .,ed .Tectonicupliftandclimatechange[M] .NewYork:PlenumPress,1998.313~ 2 2 7. …  相似文献   

14.
盆山关系研究的基本思路、内容和方法   总被引:18,自引:0,他引:18  
刘少峰  张国伟 《地学前缘》2005,12(3):101-111
盆地和造山带作为大陆岩石圈表面发育的两个基本构造单元,在空间上相互依存,在物质上相互转换和在地表形态上相互调整、均衡,两者具有密切的耦合关系。不同时期原始盆山结构、山脉变形样式、盆地充填格架及主要构造带、构造地块展布是盆山关系研究的几何学问题;山盆之间的叠加、转换和迁移历史,山脉基底和盖层剥露过程、折返机制,隆升过程,盆地的沉降方式、沉积记录和物源类型,造山带剥蚀物质的去向,山脉剥蚀量,造山带的增生方式等是盆山关系研究的运动学问题;盆山系统反映出的造山过程、区域动力学背景、深部流变学机制和调整过程及盆山演化动力模拟是盆山关系研究的动力学问题和最终目标。盆山关系研究的内容可初步确定为,不同时期的盆山几何配置关系,盆地层序地层序列与多幕构造控制关系,盆地沉积物物源与山脉剥露过程关系,盆地沉降与山脉隆升关系,地表过程与构造作用关系,盆山系统演化动力学。  相似文献   

15.
What factors control mechanical erosion rates?   总被引:1,自引:0,他引:1  
Mechanical erosion rates are important factors in understanding how continents evolve. Mechanical erosion is much faster than chemical erosion, especially for highly elevated regions of the Earth's surface. It is a principal way in which mountain ranges are removed, exposing deep metamorphic roots, which comprise much of the older portions of the continental masses. In addition, there has to be a long-term balance between erosion and mountain building. A new data set allows us to explore in greater detail some of the many factors which control mechanical erosion rates. The most important factors are some expression of the average slope of a drainage basin, some measurement of the amount of water available for erosion, some environmental measurements, and also a measurement of basin length, for which we have no good explanation. The estimate of global mechanical erosion rate obtained here is considerably lower than those obtained by some other workers, some of whom have concentrated on the fact that smaller river basins tend to get eroded faster than larger basins, and it is mainly smaller basins which have not been measured and which are therefore not allowed for by simple arithmetic averaging of observed erosion rates. It is shown here that although smaller basins are eroded faster, this is mainly because they are steeper than larger basins. We also show that extrapolation of current data to smaller basins does not work because the observed continental area which is draining to the ocean cannot be attained by the simplest extrapolation scheme. Received: 23 October 1998 / Accepted: 29 June 1999  相似文献   

16.
成煤大地构造学研究   总被引:2,自引:0,他引:2  
将大地构造学和煤地质学相结合,提出了一门新的边缘学科-成煤大地构造学。首先对它的定义,范围,方法,手段和特色作了详细阐述,把全球构造聚煤区分为域,带,盆三级。然后以中国为例,对成煤大地构造问题进行了讨论,主要是聚煤盆地和含煤建造分类,古构造对聚煤作用的制约和成煤大地构造与聚煤盆地的时空演化,海域构造聚煤带,深部构造对中,新生代煤盆地的控制作用,成煤构造地球化学,与成煤构造环境有关若干问题如灾变论,  相似文献   

17.
摘要:大陆造山带与沉积盆地之间具有十分密切的内在联系,空间上相互依存,物质上相互补偿,构造上相互作用,时间上同步演化。这些内在联系体现在统一的形成机制上:大陆造山带和沉积盆地是在大陆边缘俯冲板片脱水熔融和大陆内部地幔柱(枝)上隆的热动力作用下,地壳由盆向山侧向流动,导致盆山地壳物质发生循环运动。青藏高原与周边盆地的耦合作用十分典型。青藏高原不是印度板块与欧亚板块碰撞的结果,而是形成于下地壳流动驱动的板内盆山作用。青藏高原板内盆山耦合可分为两个阶段:(1)板内造山成盆阶段,表现为180~120 Ma→65~30 Ma→23~7 Ma从青藏高原北部和东部盆山系统→青藏高原中部盆山系统→青藏高原南部盆山系统有序迁移,以构造隆升、水平运动、地质作用和大规模板内金属成矿为特征;(2)均衡成山成盆阶段,表现为从36 Ma开始,青藏高原整体快速隆升和周边沉积盆地边缘坳陷带巨厚的磨拉石沉积,以36 Ma B.P.、25 Ma B.P.、18~12 Ma B.P.、 08 Ma B.P.和015 Ma B.P.等一系列脉动式快速隆升、垂直运动、地理作用和水系 环境变化为特征。大陆板内盆山构造演化经历从伸展构造向挤压构造的转换,伴随盆地主动作用转变成造山带主动作用。大陆下地壳流动和盆山耦合形成非安德森式的低角度拆离断层、波状起伏逆冲断层和异常共轭关系走滑断层。  相似文献   

18.
不同于具有相对稳定构造-沉积背景海相盆地的层序构型,陆相盆地的层序构型具有多样性.针对陆相盆地具有局限、封闭、类型多样、控制因素多变、多物源、古地貌差异大等典型特征,提出"陆相盆地层序构型多元化体系"的观点."陆相盆地层序构型多元化体系"是指不同类型陆相盆地在多种因素综合作用下,会形成不同的层序构型、沉积充填样式,构成陆相盆地层序构型多元化体系.该体系包含经典层序构型和特征性层序构型两大类,在系统总结不同类型陆相盆地经典层序构型的基础上,进一步介绍断陷盆地非同步叠加、迁移型、陆内克拉通盆地"溯源退积"等多种新的特征性层序构型,补充、丰富了陆相盆地层序构型多元化体系.陆相盆地层序构型多元化体系反映了陆相盆地沉积动力学过程的复杂性,可以将不同类型陆相盆地所发育的不同层序构型纳入到一个统一体系,有利于陆相层序地层学研究的系统化,丰富陆相盆地层序地层理论体系.   相似文献   

19.
Among petroliferous regions of the world, a specific place is occupied by sedimentary basins confined to continental margins at the eastern periphery of the Pacific Ocean and in the Caribbean Sea. In the Cenozoic and Quaternary, this region was dominated by tectonic activity manifested as compression, movements along large fault systems (primarily, strike-slip faults), formation of mountain chains, appearance of thick accretion prisms and foothills, and development of volcanism at certain stages. The petroliferous structures of the region are mainly represented by fore-arc sedimentary basins complicated in some places by fore- and backdeeps.  相似文献   

20.
云南新生代断陷盆地的环境地质记录   总被引:1,自引:0,他引:1  
盆地的环境地质记录是从盆地的形成、发展演变、沉积物形成的地球化学与古气候环境、沉积物堆积后所经历的压实、成岩来加以研究的。除无机介质(矿物)外的有机质,在成岩压实受热过程中化学成分与结构的变化,也是盆地环境地质记录的一部分,环境地质研究的归宿是对矿产—化石燃料形成与潜能的估价,完整的研究应该包括化石燃料形成(成烃成煤)环境及成藏(保存)环境等。对云南滇西陇川、瑞丽及保山等三个新生代断陷盆地环境地质记录的研究揭示,在极其相似的盆地形成演变、沉积地球化学与古气候、成岩与成烃背景基础上,化石燃料的形成与潜能在三个盆地具有差异性;指出陇川盆地以找寻煤型气及初熟(低熟)油为主,保山盆地以寻找浅部生物成因气及煤型气为主,瑞丽盆地相对潜能较差,仅有生物气浅部产出的可能。  相似文献   

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