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1.
滇中及其邻区的大地构造演化运动经历了原陆壳活动阶段、原陆壳“稳定”阶段、地槽、地台和地洼5个阶段,留下了相应的构造层.前地槽构造层包括活动和稳定2种类型,具有面状分布的特征,代表陆壳演化初期刚性较低的地壳特点.地槽构造层以大红山群、昆阳群和澄江组为代表,但邻区出现分异现象.地台构造层的特征表明最迟在寒武纪,本区壳体接合成为一个稳定的整体,但从奥陶纪开始古地台边缘出现陆缘扩张现象,形成局部扩张槽.地洼阶段具有中亚壳体和东亚壳体过渡性特点,地洼阶段开始的时间与东亚壳体的相同,而激烈期时间与中亚壳体的相同.通过构造层特征的分析,认为滇中及其邻区壳体成长经历了接合、同化、分异、同化的过程.  相似文献   

2.
从沉积建造、岩浆建造、构造型相和地质发展史角度,论述了钦州地区的大地构造特征。该区在早古生代隶属华南地槽区,加里东运动后,在华南其它地区已进入地台区情况下,仍然为地槽。东吴运动期间,该地槽封闭,并随即开始了地槽阶段晚期——褶皱带期,为一个残留地槽。印支运动后,又同华南其它地区一起,演化到地洼区阶段,成了东南地洼区的一部分。由此可见,钦州地区是一个超越了地台阶段的地洼。它与其它经由地台阶段的地洼相比,具有如下特征:(1)残留地槽具有继承性特征,仅出现于其负地槽部位;(2)它的出现受控于长期活动的深断裂;(3)在残余地槽间的活动性稍差,而在地洼阶段早期的活动性较强。  相似文献   

3.
本文从沉积建造、构造类型、结合岩相厚度的分析以及与鄰区地槽在地质构造上的形成和发展,讨论了浙西地区大地构造性质,並把它归属於华南加里东地槽褶皱区的浙西、皖南加里东地槽系的内部继承地槽拗陷,在这个地槽内又划分出四个构造——建造带。同时本文也论述了本区褶皱构造的成因,地壳构造形成和发展的两种形式——继承与上迭构造等问题。此外,也涉及到与上述问题有关的地槽褶皱作用的问题,在空间上地槽褶皱作用具有从两侧向中间迁移的发展历史,在时间上地槽褶皱作用远远落后於地槽沉积建造的结束,以及在同一地槽内地槽“封闭”具有不同形式的问题。  相似文献   

4.
通过对本区沉积建造、岩浆建造、变质作用、构造型相、地壳运动型式、地貌、新构造等项特征分析。认为本地区经历了前地楷阶段、地槽阶段、地台阶段和地洼阶段、金矿床是在多次构造─—岩浆活动中于中生代燕山晚期地洼阶段形成。太古界胶东群是本区金矿床主要矿源层。岩浆活动主要起成矿物质转移站作用;构造活动控制金矿的形成分布和矿体的规模、形态等。金矿床具有成矿物质多来源、多成矿作用、多控矿因素多大地构造演化阶段、多成因类型等特征,属于漫──壳矿床。图2,表2参10。  相似文献   

5.
皖南南部构造性质及构造单元的归属的争论,在最近一次全国性编图会议,意见仍未统一。作者在实际调查材料的基础上,运用构造——建造分析和比较大地构造的方法研究了本区前寒武纪及早期古生代各时代建造成分,确定了各建造的名称、性质和空间分布特征,进一步划分出几个不同性质的建造序列;描述了不同时代地层和不同空间的构造形态,划分了构造层及构造形态的级别,並分析了构造形态形成的原因;论证了本区加里东运动的存在及其性质。在上述资料基础上,阐明了本区是华南加里东地槽区皖南浙西加里东地槽系的重要组成部分,並对皖南加里东地槽与其北隣的下扬子台缘沉陷带的界限予以确定,进一步说明了本区在加里东旋迴是冒地槽,具有残余地槽和边缘地槽拗陷的特性。  相似文献   

6.
本文详细阐述了福鼎南溪石炭系海相沉积物的岩石组合类型、韵律层理、颜色标志、同生砾岩和同生褶皱构造等特征,发现它是典型的地槽相复理石沉积建造。作者由此得出结论:浙闽沿海中生代火山岩基底不再是“前震旦纪华夏古陆”,而是海西印支地槽褶皱带。  相似文献   

7.
广东海南岛石碌矿区内的现知铁矿床,都属于多因复成矿床。但其基础矿床先后成于两个不同的大地构造发展阶段,分属于两种不同的大地构造类型,一为地槽型沉积变质矿床,一为地台型沉积矿床。前者的含矿地层为石碌群(相当于前人的“石碌群”下部,即SL1-6层),后者的含矿地层为石灰顶组(相当于原“石碌群”上部的“SL7层”,因其沉积建造不同,与SL6层之间又有不整合面分隔,故划分出来)。本文建议将“石碌式铁矿”一名专指以改变界限后的石碌群中的地槽型沉积变质铁矿为基础,后经地洼岩浆成矿作用改造迭加进一步富化而成的那种铁矿床,并从大地构造角度主要对该式矿床的形成条件和找矿方向问题试作探讨。  相似文献   

8.
乌鲁木齐祁家沟剖面为北方地槽区中上石炭统的标准剖面。中石炭统祁家沟组和上石炭统奥尔吐组底部为一套风暴流沉积,主要标志有类似Bouma序列的沉积层序、壶模(pot cast)、“口袋状构造”、风暴介壳层、“亚里士多菲库”构造(Aristophycus)、成岩晕圈、丘状层理、液化泄水构造、冲刷-充填构造、冲刷面叠瓦状滞留砾石、定向排列的滞留生物以及撕裂状内碎屑。岩层不稳定,横向变化大。生物均为原地埋藏或经短距离搬运改造的正常浅海生物。  相似文献   

9.
不久以前,作者等就华南加里东地槽褶皺区构造的基本特征作了初步总結。文章主要是論述了华南加里东地槽褶皺区的前寒武紀晚期和加里东期建造序列和构造特征及其分区;华南加里东地槽褶皺区和华北地台交接的构造型式;作为东半球太平洋块段的华南加里东地槽褶皺区和位于西半球大西洋块段的北欧斯堪的那維亚和苏格兰加里东褶皺带地质构造所表现的差異性。本文是作者等在进一步闡明地槽、地槽系和地槽区的概念的基础上着重就华南加里东地槽褶皺区构造层的划分及雪峯运动在本区的性质和表现,江南地背斜带隆起分割的边緣地槽拗陷和內部地槽拗陷震旦紀及早期古生代地质构造基本特征和发展历史的差異性,晚期古生代和中生代地质构造形成和发展基本特征,以及华南加里东地槽褶皺区大地构造性质等系列問題予以专門的討論。作为第一篇論文的继續补充和发展。  相似文献   

10.
永梅坳陷带铜银矿床区域控矿规律与成矿模式   总被引:1,自引:0,他引:1  
永梅坳陷带是我国华南地区重要的铁铜多金属成矿带.本文探讨了该成矿带中铜(伴生)银矿床的区域控矿规律及成矿模式.重点研究了沉积环境、岩相建造、不同类型构造、火山活动及热水活动对铜银成矿的控制作用.研究结果表明,铜银成矿作用主要发生在各大地构造演化时期的裂陷拉张阶段,空间上分布于相应时期形成的坳陷盆地及其有关的沉积建造中,矿床定位于同沉积断层控制的次级洼地、层间破碎带及火山构造中,成矿作用与热水活动和火山活动具有密切关系,并显示出多阶段叠加和改造的特点.  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 Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
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   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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