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1.
综合利用露头构造解析、地震剖面解释、锆石和磷灰石裂变径迹年龄和沉降-沉积等资料,对川西-龙门山盆山系统沿走向的构造变形、差异隆升-剥蚀和沉积记录进行系统梳理,探讨龙门山冲断带和川西前陆盆地系统的走向差异演化特征及其关键构造变革期.受控于本身的地质结构差异及周缘多个构造带的多期交互作用,龙门山冲断带和川西前陆盆地在构造、隆升和沉积等方面都表现出明显的走向差异.龙门山冲断带自北向南总体上具有韧性减弱、脆性增强、构造定型时间变新的趋势,龙门山北段和盆地北部定型于燕山期,而龙门山中、南段和盆地南部定型于喜马拉雅期.中生代期间,龙门山北段隆升较快;而新生代期间,龙门山中、南段隆升较快.川西前陆盆地同样表现出南北差异隆升的特点,北部隆升较早,大约在45 Ma B.P.;而南部隆升较晚,在20~25 Ma B.P..川西(北)前陆盆地的沉降中心经历了4次明显的迁移,即从晚三叠世的龙门山中段前缘向东北迁移,中侏罗世到大巴山-米仓山前缘,晚侏罗世-早白垩世向西迁移至米仓山-龙门山北段前缘,于晚白垩世-新生代期间再次向南迁移到龙门山中-南段前缘.龙门山冲断带和川西前陆盆地的走向差异演化表现为印支期向南递进扩展、燕山早-中期南北分异和燕山晚期-喜马拉雅期北隆南降.龙门山冲断带和川西前陆盆地经历了晚三叠世、中侏罗世、早白垩世和古近纪4个关键构造变革期.晚三叠世构造变革期包括龙门山水下隆起和海相前陆盆地(马鞍塘组上部至小塘子组)、龙门山局部隆升和海陆过渡相前陆盆地(须家河组第二至第三段)以及龙门山全面隆升和陆相前陆盆地(须家河组第四至第五段)三大阶段,主要受控于扬子构造域并受秦岭构造域的强烈影响.中侏罗世构造变革表现为扬子构造域向秦岭构造域的转变;早白垩世构造变革表现为秦岭构造域向青藏高原构造域的转变;古近纪构造变革表现为川西前陆盆地由沉积向剥蚀状态的转变.  相似文献   

2.
龙门山中段川西前陆盆地初始盆山边界及其变迁   总被引:3,自引:0,他引:3  
通过对龙门山中段造山带、前陆盆地、飞来蜂的构造变形和构造演化研究,结合前陆盆地物源分析.确定了盆山转换时期川西前陆盆地初始盆山边界,重塑了盆山边界的变迁过程.研究表明,盆山转换初期川西前陆盆地盆山初始边界断裂为茂汶断裂,现今分布于冲断带内的飞来蜂均来自于茂县-汶川断裂与北川-映秀断裂之间的区域.印支-燕山期造山带向南东挤出,使位于茂县-汶川断裂带与映秀-北川断裂带问的地层发生交形和冲断隆升,形成北东向构造.作为前陆盆地基底的海相碳酸盐岩地层逐渐被抬升剥露,成为飞来蜂的源.随着造山带不断地冲断隆升,前陆冲断带向南东扩展,盆山边界由初始的茂县-汶川断裂依次向南东迁移至北川-映秀断裂、彭-灌断裂和关口-彰明断裂以东.  相似文献   

3.
以盆地构造-沉积分析为手段,研究了印支期以来川西前陆盆地与龙门山造山带的耦合关系,探讨了川西前陆盆地的构造演化及其对油气藏的控制作用.认为龙门山造山带是经历了印支期、燕山期和喜马拉雅期多期、多类型推覆叠加而形成的复杂地质体,因而造成川西前陆盆地经历了前陆、坳陷、再生前陆的沉积充填过程,该区盆山耦合模式主要为剖面上的前展武逆冲双重构造,平面上表现为NE构造带和近EW向的横断层;造山带和盆地的共同演化不仅形成了多套烃源岩.而且控制了油气保存与有效成藏区带.逆掩推覆带和前陆坳陷带是油气勘探的有利区带.  相似文献   

4.
2008年的汶川地震为分析龙门山与四川盆地形成演化过程中的山-盆相互作用及其动力耦合机制提供了新的视角与依据.在总结分析龙门山与川西前陆盆地地层构造特点的基础上,从汶川地震的基本特征分析入手,探讨了龙门山与四川盆地的现代动力耦合作用机制及其对川西深层油气二次运移聚散的影响.龙门山的形成演化与地震孕育主要受其西侧松潘-甘孜地块的逆冲和其东侧四川盆地的俯冲的非对称相向挤压控制.龙门山南北两段的地质构造与构造动力环境有较大差异.龙门山晚三叠世开始隆升,其形成早于青藏高原的隆升,与印-亚板块的碰撞无关;但喜马拉雅期以来的演化受印-亚板块碰撞和太平洋板块俯冲的影响.龙门山的冲断褶皱变形垂直于山脉走向从西北向东南,即从松潘-甘孜地块向四川盆地逐渐扩展;平行于龙门山走向发育的断裂带控制川西油气聚散带的分布,前山断裂带上盘及以西地层中的油气基本散失,山前隐伏断裂带有利于深生浅储气藏的形成.  相似文献   

5.
依据龙门山中段中生代盆地的基底性质、沉积构造组合和构造变形,论证了川西拗陷是在印支期发育于扬子板块活动大陆边缘的弧背(前陆)盆地,前陆盆地的构造变形是经印支期构造变动和喜马拉雅期叠加改造形成的推覆构造;并讨论了龙门山中段中生代前陆盆地的构造演化历史。  相似文献   

6.
龙门山前陆盆地充填序列   总被引:1,自引:0,他引:1  
文章以构造地层学和层序地层学相结合的综合地层学分析方法作为分析龙门山前陆盆地的基础,以不整合面和其对应面作为分割盆地充填序列的基本界面,并按不整合面的规模和性质,将龙门山前陆盆地充填序列分割为6个构造层序和14个层序,初步查明了龙门山前陆盆地充填序列和沉积体系三维空间配置模式及其在时间上的演变,建立了龙门山前陆盆地地层格架和充填模式。  相似文献   

7.
银川盆地具有独特的地质背景,不同于中国西部其他以挤压为特色的新生代沉积盆地。文章基于前人的研究成果和中石化近期投入的大量实物工作量,应用盆山一体化的研究思路,恢复了银川盆地中生代以来的演化过程;认为其经历了晚侏罗世和渐新世时期2次明显的盆山转换过程,晚侏罗世盆山转换的主控因素是燕山运动引起的构造应力场的改变,渐新世时期的深层次控制因素是深部热体制的变化,这种变化直接导致浅部应力场由挤压转为拉张伸展环境。银川盆地与其东侧的贺兰山具有较好的耦合关系,两者在成因上密切相关,既相互依存、相互作用,又同步演化,贺兰山东麓断裂在空间上发挥了直接的"桥梁"作用。  相似文献   

8.
龙门山造山带是扬子板块的西延部分,主要受到3条断裂的控制,分别是汶川-茂汶断裂、北川-映秀断裂和江油-灌县断裂.在扬子板块与松潘-阿坝地块的挤压下,龙门山于印支晚期开始褶皱隆升造山,在造山的过程中控制造山带的3条主要断层由正断层转换成为逆断层.综合前人的观点,通过野外基础地质调查并利用平衡剖面法恢复了龙门山的造山过程,并建立了造山带构造演化模式.结果表明,龙门山在造山初期主要是受到北西方向力的作用;晚三叠世末期主要受到由于东南方向太平洋板块的挤压而迫使扬子板块挤压的应力作用;燕山期龙门山造山带继承了印支期的逆冲推覆构造作用继续上升;喜玛拉雅期推覆构造进一步发展,在推覆构造活动加剧的同时,由于重力作用,使被推到高处的不稳定岩体大量下滑,形成滑覆体和推覆体叠加的构造格局,最终演化为现今的构造样式.  相似文献   

9.
通过对东秦岭-大别山造山带南缘鄂东地区、荆当盆地、秭归盆地和川东北地区三叠纪-古近纪的构造层序对比研究,划分出三个大的构造层序,并分析了中上扬子地区印支期以来沉积盆地性质转换和迁移过程与构造层序的耦合关系,揭示了东秦岭-大别造山与成盆作用过程.认为早三叠世至中三叠世构造层序Ⅰ记录了扬子地台由克拉通盆地逐渐萎缩的过程,反映了印支期华北板块与扬子板块之间软碰撞未造山的过程;晚三叠世至早白垩世构造层序Ⅱ记录了前陆盆地的三次幕式演化过程,反映了早燕山期华北板块与扬子板块之间呈斜向、剪刀式由东向西陆-陆碰撞关闭以及前展逆冲叠置造山作用过程,与江南逆冲带联合作用形成前陆盆地沉降和沉积中心向西的迁移.晚白垩世至古近纪区域构造背景发生重大变化,构造层序Ⅲ记录了晚燕山期地壳快速均衡隆升,伸展断陷盆地形成演化过程.  相似文献   

10.
渤海湾地区中西部中生代构造特征及演化   总被引:1,自引:0,他引:1  
应用周边露头资料、盆内钻井资料及地球物理资料,以板块构造理论为基础,以构造演化阶段论和活动论为指导,采用构造解析法对渤海湾地区中西部中生代各期构造变形场、构造应力场及沉积盆地进行了研究。研究结果表明,渤海湾盆地中西部中生界可划分为4个构造层:印支期构造层、燕山早期构造层、燕山中期构造层及燕山晚期构造层。成盆期主要经历了早中三叠世大型陆内坳陷盆地、早中侏罗世河湖沼相中小型坳陷盆地、晚侏罗世—早白垩世陆内小型裂陷盆地及晚白垩世隆起背景上形成的小型坳陷盆地等。造山期经历了印支晚期(T3)准造山作用、燕山早期(J2末)强烈造山作用及燕山晚期(K2)准造山作用3个演化阶段。中生代构造样式以挤压褶皱、逆冲构造及张性正断裂为主,其次发育横向调节构造。燕山运动早期对本区作用最大,奠定了本区北北东向的构造体系。中生代构造演化型式与欧亚板块东部的伊佐奈畸板块的相对运动方式密切相关  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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