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1.
出露在胶东一带的前震旦系胶东群,是一套经历了多期构造变形的变质岩系。研究这一课题,对深入认识胶东地区的地壳演化、古构造特征以及地层的划分等重大地质问题有着重要的意义。本文指出:胶东群构造旋回的褶皱序列可划分为四期变形,各期的褶皱样式、规模和方向都具有不同的特征。根据本区几期褶皱发育的特点和各期叠加干涉的型式表明,这套古老的变质岩系是经历了多期构造运动作用,其变形总趋势是由第一期的强烈的构造置换和层内塑流为特征的小型褶皱开始,演变至第四期的开阔宽缓弱塑性变形的大型褶皱而告终。这一变形过程反映出温压条件由高向低变化的递减规律。此外,本文还对塑流褶皱的成因机制、胶东群的地层划分以及褶皱露头的分析等问题进行了讨论。  相似文献   

2.
试论变质岩地区地层研究的构造地层学方法   总被引:1,自引:0,他引:1  
构造地层学方法是变质岩,尤其是前寒武纪变质岩地区地层研究的有效方法。由于变质岩系经历了强烈(或多期)变质作用和形变作用,使其原岩成分、组构都发生明显变化。因此,一般生物地层学和岩石地层学方法都难以进行合理的地层划分与对比。构造地层学方法可以具体划分为八个主要工作步骤,归纳起来从局部构造研究着手,搞清岩层相对层序,建立地层组、段,最后恢复全区构造轮廓。文中详细分析了通安、黎漠地区的两个实例。  相似文献   

3.
许江坤 《山西科技》2009,(3):126-127
在贵州东南部与广西、湖南交界地带分布着大面积古老的浅变质岩地层,其独特的工程特性给在建的厦蓉高速公路带来严重的地质灾害,极大地增加了工程成本和施工难度。文章阐述了黔东南一带浅变质岩地层工程特性及变形破坏机制,并对公路建设过程中的边坡防护治理措施进行初步探讨。  相似文献   

4.
本文提出确定变质岩区褶雏形态的一种新方法——构造透镜体法。这种方法的理论依据就是构造置换。  相似文献   

5.
根据构造解析的观点讨论了皖中桥头地区变质岩的构造变形历史和层序。认识到; (1)横山组经历了复杂的构造置换,在横山组和双山组之间有一斜交不整合存在,称之为桥头集运动。 (2)双山组的时代应划属于震旦纪,甚至更新。  相似文献   

6.
研究浅变质岩系中原生沉积构造特征,鉴别岩层的新老层序,确定其形变构造特征,这对建立正确的变质岩系地层层序十分重要,尤其在缺乏化石证据的前寒武纪地层中,更为如此。我们应用这一套构造地层学方法成功地确定了伯顺岬地区出露的海克拉霍克岩系总体处于倒转状态,从而纠正了过去以正常地层层序为出发点,认为该区下部的白云岩老于上部的石英岩的传统看法。在前人资料的基础上进一步修改并建立了伯顺岬及其邻区海克拉霍克岩系新的地层层序。  相似文献   

7.
东大别超高压变质带构造研究进展   总被引:2,自引:1,他引:2  
大别山造山带的形成和演化主要经过南北板块碰撞、碰撞后超高压变质岩折返和燕山早期穹隆构造形成3个构造阶段,其主体构造格架由碰撞后超高压变质岩折返过程中的伸展作用和燕山早期穹隆构造所形成.文中根据不同岩石单元在超高压变质岩折返和穹隆构造形成中的构造表现,以主期构造特征及其后构造演化的一致性为原则,将东大别造山带的变质岩系分为南大别岩片构造带、中大别穹隆构造带和北大别隆滑-逆冲构造带3个构造单元,系统论述了各构造单元构造变形的几何学和运动学特征,从造山带整体构造演化的角度厘定出3个阶段的5期变形,探讨了它们在大别山构造演化和超高压变质岩形成和折返中的动力学意义.  相似文献   

8.
黔西南三迭系碎屑岩地层中,发育一种与变质岩区发育的杆关构造相似的滚动构造,经笔者研究认为,其成因为层间滑动所致,形成过程可分为剪切破裂,剪切旋转和滚动磨园等三个阶段。  相似文献   

9.
通过对四川盆地中央平缓区内威远隆起三叠系地层的构造几何学和运动学解析发现, 下三叠统地层呈近南北走向的宽缓褶皱变形, 而其上覆中、上三叠统地层和下伏古生界地层均为近东西和北东走向的褶皱?断裂构造形迹, 表明下三叠统嘉陵江组地层构造变形与上下层系的构造变形解耦, 分析认为该构造解耦是早三叠世末期印支构造变形事件的重要响应和记录, 保存于三叠系地层中的这一构造解耦事件暗示威远隆起是印支构造运动的直接产物, 是印支期构造古隆起。从褶皱样式与破裂相关性分析, 认为威远褶皱型古隆起及其相伴生裂缝是威远古生界气藏赋存的重要方式。  相似文献   

10.
川北米仓山东西向伸展的变质岩内火地垭群变质岩系中,藏有丰富的大理岩资源。大理岩矿床沿大河坝一关坝冲断带出露。按矿床构造的形式,可分为压扁型和断块型两种矿床类型。 压扁型矿床产于上两组内,断块型矿床产于麻窝子组内。它们的形成均与区域变质作用、变形压扁及置换作用有关。由于两者的岩石组合不同,因而矿体形态和矿床构造各异。上两组板岩中夹薄层大理岩,故形成雁列式、串珠状、钩状大理岩矿体;麻窝子组由厚层大理岩组成,则形成带状、层状和透镜状矿体。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
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   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
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   

18.
19.
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   

20.
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   

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