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1.
华南加里东期陆内构造属性探讨   总被引:5,自引:0,他引:5  
通过江绍断裂带两侧加里东期地层沉积相的横向对比,对桂阳泗州山、分宜松山冰碛砾岩的分布特征及花岗岩发育规律进行研究,并对华南加里东期的构造属性进行探讨.结果表明:江绍断裂带两侧南华系-寒武系沉积相指状交叉现象明显,下奥陶统相特征趋于一致,不存在截然跳相现象;扬子陆块中海相冰硕岩与浊积砂岩互层、华夏陆块中海相冰碛砾岩的存在说明扬子和华夏之间物源是相通的,之间没有大洋相隔;华南盆地不是一个原始大洋,而是在陆壳基底上由有限拉张形成的以过渡壳为基底的裂陷海槽.  相似文献   

2.
孔雀河斜坡与库鲁克隆起构造-热演化史研究   总被引:4,自引:0,他引:4  
目的 探讨孔雀河斜坡与库鲁克塔格隆起盆山关系及其构造热演化历史.方法 利用构造解析、镜质体反射率、磷灰石及锆石裂变径迹分析等方法,研究孔雀河斜坡与库鲁克塔格隆起盆山关系及其构造热演化历史.结果 孔雀河斜坡区中新生代以来表现为平缓的斜坡,无明显的前陆拗陷.寒武-奥陶纪孔雀河地区及库鲁克塔格地区处于拉张环境,盆地原型为大陆裂谷盆地;志留-泥盆纪孔雀河地区为一种挤压环境,盆地类型为陆缘拗陷盆地;孔雀河地区侏罗纪呈现出陆内断陷盆地特征.库鲁克塔格隆起至少经历了两次隆升过程,分别是海西期和晚白垩世以来.结论 孔雀河斜坡与库鲁克塔格隆起发育海西、燕山两期重要的构造运动,主构造变形期为早海西期,变形以褶皱及与之相伴的逆冲断裂为主要变形样式.盆山构造热演化史研究表明早海西期寒武系一下奥陶统烃源岩达到最大埋深和最高热演化程度,寒武系一下奥陶统烃源岩主生烃期为加里东晚期-早海西期.早海西期之后孔雀河斜坡寒武系一下奥陶统烃源岩不具有二次生烃条件.孔雀河斜坡油气勘探方向应以形成于海西期且后期保存好的圈闭为主.  相似文献   

3.
中天山早古生代离散地体构造的讨论   总被引:6,自引:0,他引:6  
中天山造山带的基底性质长期以来是天山大地构造研究中最有争议的问题之一。本文在比较研究中天山及塔里木北缘中晚元古代至古生代地层的基础上,认为中天山不存在连续的“前寒武系隆起带(或结晶轴)”,它是由寒武纪后从塔里木大陆北缘离散出来的若干地体组成。由于早古生代时期中天山地体的离散,形成了具洋壳性质的南天山边缘海盆地。库米什北夹于蛇绿混杂岩带中间的片麻状——眼球状花岗岩块体,是一个残留于边缘海盆地中的陆壳碎块(地体)。  相似文献   

4.
塔里木盆地早中寒武世张裂构造及沉积响应   总被引:1,自引:0,他引:1  
塔里木盆地塔中、巴楚地区中下寒武统发育半地堑和正断裂,说明早中寒武世塔里木盆地为张裂构造环境;半地堑在平面上呈带状分布,纵向发育具有继承性;正断层的平面组合形态呈侧列式和雁列式,断层断距自西向东逐渐增大。张裂构造是离散大陆边缘形成时强烈拉张作用的产物,半地堑的形成与塔西南被动大陆边缘和塔东克拉通边缘拗陷的形成有关,受盆地东北缘三叉裂谷系发育的影响更为明显。断裂体系控制着盆地的沉积格局和充填演化,盆地整体呈现台地相—斜坡相—半深海盆地相的沉积格局,而半地堑的走向呈NW—SE向,与隐伏基底断裂走向一致,其沉积模式为灰岩—云岩—膏岩—盐岩—红层沉积。  相似文献   

5.
塔里木盆地寒武系油气勘探的突破很大程度上取决于烃源岩的发育和分布状况.基于古气候、生物发展的分析,认为早寒武世具有发育烃源岩的条件.寒武系沉积古地形分析显示,塔里木盆地寒武系基底存在古隆起,从台地中心到深海盆地,仍发育泻湖,这些为烃源岩的发育提供了物质条件和古地理条件,古隆起提供了泥质来源,深海盆地和闭塞海湾提供了烃源岩沉积环境,也控制了烃源岩分布.同时,围绕古隆起应该发育粗粒碎屑沉积物,是未来除白云岩和灰岩储层以外的、值得重视的另一类储层.  相似文献   

6.
对楚雄盆地地震资料进行解释,在盆地内发现了多条地腹深大断裂,被中生代红层所掩覆,这些隐伏基底断裂与盆缘、盆内控盆基底断裂,共同控制盆地层块分异的构造-沉积演化过程.发现了对中生代盆地沉积具有控制作用的地腹大型隐伏深大断裂——石羊断裂,认为该断裂是楚雄盆地晚三叠世早期滇中裂谷西支——程海—祥云地堑的东边界控制断裂,并重新认识了中生代楚雄盆地性质、形成机制及复杂的构造-沉积演化过程.认为晚三叠世楚雄盆地是经历裂陷-坳陷沉积过程的伸展盆地,建立了晚三叠世挤压构造背景下的裂陷作用与挤压-裂陷盆地模型,落实了云南驿组海相烃源岩分布范围,提出了新的海相目的层系有利勘探目标区.此外,发现了盆地东部寒武系沉积西边界,重新厘定了早寒武世高水位期沉积范围及页岩气勘探有利区域,重新认识了楚雄盆地有利油气保存单元分区,对下一步油气勘探具有指导意义.  相似文献   

7.
下扬子地区盆地的"四层楼"结构及其动力学机制   总被引:11,自引:1,他引:10  
下扬子地区震旦纪以来经历了不同的大地构造与地球动力学背景 ,盆地演化相应地经历了震旦纪—中三叠世海盆→晚三叠世—中侏罗世沿江前陆盆地→晚侏罗世—早白垩世火山岩盆地→晚白垩世—早第三纪陆相伸展盆地。下扬子地区震旦纪—中三叠世海盆发育于伸展性被动大陆边缘。沿江前陆盆地形成于扬子与华北板块碰撞活动中的前陆变形带上。火山岩盆地出现于区域性走滑剪切和环太平洋岩浆弧背景下。库拉—太平洋板块高角度、高速正面向东亚大陆下的俯冲 ,造成了岩石圈上拱拉张 ,从而产生了晚白垩世—早第三纪的陆相伸展盆地。随着西太平洋边缘弧后盆地的出现及印度与欧亚板块的碰撞 ,中国东部遭受近东西向挤压 ,从而结束了下扬子地区的盆地演化历史。  相似文献   

8.
大别造山带北缘(北淮阳)古生代各构造-地层岩片变火山岩、变沉积岩显示了具有高放射性和低放射性成因的两类铅同位素组成特征,块体效应明显,且具有一定的规律性.与秦岭造山带主要构造单元特征的铅同位素组成对比表明,定远组构造岩片可能是南秦岭构造单元或扬子陆块北缘的成分;龟山组、南湾组-佛子岭群、石炭系岩片则属于北秦岭构造单元,它们是北秦岭构造带的东延部分.结合地质体之间的分布关系判断,在大别造山带,扬子陆块与华北陆块在古生代的俯冲消减带应当位于南湾组-佛子岭群岩片的的北界或它们所覆盖地段之下的某个位置.  相似文献   

9.
综合分析川东南地区深层油气地质条件,探讨该地区上震旦统灯影组油气勘探前景。利用钻井、地震及露头资料,结合静态油气成藏条件进行动态油气成藏研究,结果表明:从烃源角度,川东南地区具备了形成大油气田的物质基础;储层方面,灯影组顶部均有岩溶储层发育,且储层内可见沥青充填,说明早期确有成藏;封盖条件方面,川南至川东一带中上寒武统膏盐岩十分发育,是良好的区域性盖层。研究区形成的圈闭受后期构造变动发生变化,自身封存条件改变,闭合面积减小;并且该地区靠近盆地边缘,隆升幅度大,油气的再次运移和侧向逸散情况严重。在盆地内侧,灯影组在寒武系膏盐层下的构造变化较小,圈闭形成早且持续存在,古构造保持较完整,可以有效并长期聚集油气,具有一定的勘探价值。川东南下组合虽然勘探难度大,但毗邻拉张槽的赤水地区仍有较大的勘探潜力。  相似文献   

10.
海西-印支期中国南方的盆地演化与层序格架   总被引:14,自引:0,他引:14  
加里东运动以后,扬子和华夏陆块拼合成统一的华南板块.自早泥盆世至中二叠世茅口期,华南板块和西边的三江构造区开始了以伸展作用为主的海西运动,中国南方的沉积、构造演化具有被动大陆边缘的性质,盆地类型则从陆内裂陷盆地演变为被动陆缘裂陷盆地.以东吴运动为标志,中国南方开始了印支运动,其板块活动转变为活动大陆边缘,进入到弧后盆地和前陆盆地阶段.因此,海西-印支运动构成了一个完整的构造旋回.据此,将海西-印支旋回划归为一个一级层序,再根据不同时期,盆地所处的演化阶段和盆地类型的差异,划分为6个二级层序.其中,二级层序SS1~SS5反映了海西期中国南方从陆内裂陷盆地到被动陆缘裂陷盆地所经历的初始拉张-拉张发展-停滞-成熟的全过程,而二级层序SS6却反映了印支运动早期弧后盆地和前陆盆地的形成发展历程.  相似文献   

11.
With the summarization of the Early Paleozoic paleomagnetic data recently obtained from the three major blocks of China, the Early Paleozoic (i.e. Cambrian and Ordovician) paleogeographic positions of the North China, South China and Tarim blocks were discussed in detail. The North China, South China and Tarim blocks were inferred to be located adjacent to East Gondwana in low latitudes of the Southern Hemisphere during the Early Cambrian. During the Early-Middle Ordovician, the South China and Tarim blocks were also located in low latitudes of the Southern Hemisphere with some affinities of the Gondwanaland, whereas the North China block may have episodically separated from the Gondwanaland, and might be sited close to the North America and Siberia. The reestablished paleogeographic configurations are in agreement with the studies on the biogeography, paleoclimate and sedimental facies of the North China and South China blocks.  相似文献   

12.
塔里木盆地石油地质基本特征   总被引:2,自引:0,他引:2  
全面系统地总结并提出塔里木盆地10大石油地质基本特征:(1)塔里木盆地为一古生界克拉通盆地与中新生界前陆盆地组成的大型叠合复合型盆地;(2)塔里木盆地经历了多期构造运动及多个演化发展阶段;(3)塔里木盆地主要有寒武—奥陶系、石炭—二叠系,三叠—侏罗系3套烃源岩;(4)塔里木盆地发育多套深埋优质储层及5套良好储盖组合;(5)塔里木盆地油气水性质复杂、油气藏类型丰富多样;(6)塔里木盆地富油又富气,天然气藏以凝析气藏为主;(7)塔里木盆地既有陆相油气,又有海相油气,已发现的石油以海相成因为主,天然气以陆相成因为主;(8)塔里木盆地已发现的油气藏以中小型为主,具有埋深大、丰度低、产能高的特点;(9)塔里木盆地具有多个成油气系统、多期成藏及油气多次运移再分配的特点;(10)塔里木盆地油气分布十分复杂,油气聚集受多重因素制约  相似文献   

13.
The Cambrian trilobite Bathynotus is a special morphology of Redlichiid,which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long,backwardly directed spine.Additionally,its 12th and 13th pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural spine.The genus is widely distributed,occurring in North America,Siberia,the Altay-Sayan fold belt of Russia,South China,the Tarim Basin of China,and Australia.It occurs primarily in deposits of the upper part of the continental slope,at the transition between stable platform settings and subsiding margins of the late Early Cambrian.Here,we recognize three species of Bathynotus from China,including B.holopygus which is widespread around the world.Although six species of Bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia,data presented here suggest that only three of these species are valid.Bathynotus exhibits a short geological range,with its first occurrence late in the unnamed Cambrian Series 2 and the last appearance datum of Bathynotus at the boundary of Cambrian Series 2 and Cambrian Series 3.The late appearance datum (LAD) of Bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2 and Cambrian Series 3.  相似文献   

14.
The Cambrian trilobite Bathynotus is a special morphology of Redlichiid, which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long, backwardly directed spine. Additionally, its 12th and 13th pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural spine. The genus is widely distributed, occurring in North America, Siberia, the Altay-Sayan fold belt of Russia, South China, the Tarim Basin of China, and Australia. It occurs primarily in deposits of the upper part of the continental slope, at the transition between stable platform settings and subsiding margins of the late Early Cambrian. Here, we recognize three species of Bathynotus from China, including B. holopygus which is widespread around the world. Although six species of Bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia, data presented here suggest that only three of these species are valid. Bathynotus exhibits a short geological range, with its first occurrence late in the unnamed Cambrian Series 2 and the last appearance datum of Bathynotus at the boundary of Cambrian Series 2 and Cambrian Series 3. The late appearance datum (LAD) of Bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2 and Cambrian Series 3.  相似文献   

15.
王曰伦(1903—1981年)是著名地质学家、我国前寒武纪地质学的开拓者和奠基人之一。他对我国前寒武纪地质研究的主要贡献是:初步确立西南地区早寒武世地层层序和与震旦系的分界;初步奠定了五台山区早前寒武纪构造地层基础;参与发现、命名和进一步证实“蓟县运动”的存在,正确解决了华北震旦系与寒武系的分界问题;最早发现南北震旦系属同名异纪的上下关系;为全国各地上前寒武系划分和对比做了大量开创性工作,奠定了坚实的基础。他是坚持实践和创新的楷模。  相似文献   

16.
中国南方大地构造演化及其对油气的控制   总被引:28,自引:0,他引:28  
按照板块构造理论及活动论、阶段论的思想,大致以中晚三叠世为界,将中国南方自震旦纪以来大地构造演化历史划分成海相盆地演化阶段(Z-T2)及陆相盆地演化阶级(T3-Q)两大阶段;又可进一步细分为扬子克拉通及其周缘裂谷盆地(Z-1q)、裂谷-克拉通-被动大陆边缘盆地(1c-O1)、被动陆缘-克拉通-前陆盆地(O2-S)、加里东运动(S末)、裂谷-克拉通盆地(D-T1)、克拉通残留海盆-弧后(浊积)盆地(T2)、印支运动(T2-T3)、华北-华南板块焊合、古特提斯封闭与前陆盆地的形成(T3-J2)、压扭背景下的改造作用及拉分盆地的形成(J3-K1)、伸展-裂陷盆地的形成(K2-E)、喜马拉雅运动(E末-N初)及披盖性构造层的形成(N-Q)12个阶段。特别是对南方自中晚三叠世以来的大地构造演化及其对现存油气的控制作用进行了系统研究,提出了晚侏罗世-早白垩世燕山运动对南方中生界、古生界原生油气藏的保存与破坏起到了决定性作用及燕山、喜马拉雅运动控制了现今南方原生、次生及再生烃(二次生烃)油气藏分布的新观点。  相似文献   

17.
中国的红层及发育的地貌类型   总被引:19,自引:0,他引:19  
中国的红层主要分布在西南、华南、华中及西北的广大地区 .红层主要形成于三叠纪至早第三纪的炎热、干燥的地质历史时期 .红层岩石组成多为砂岩和砾岩 ,并夹粉砂岩、页岩、泥岩、灰岩、石膏及岩盐等 ;各地区、各时代地层所夹岩层不同 .红层为陆相碎屑沉积物 ,形成于古盆地和湖泊环境 ,许多盆地和湖泊受到了后期的构造运动的影响而抬升 .由于各地区红层受到构造影响的强度及方式的不同 ,所含夹层岩性不同以及所受外力作用不同 ,使得在红层上发育了多种地貌 ,如方山、丘陵、高原、丹霞地貌等 .红层地貌与丹霞地貌应严格区分开来  相似文献   

18.
中国范围内没有洲级古陆,一些小陆块围绕西伯利亚逐步拼合而成大陆。陆块及其间洋壳相继俯冲、碰撞,导致多旋回构造运动和海陆广泛沉积。最能体现中国特色的是后期俯冲碰撞,引发古缝合线重新活跃,板内岩石圈下部俯冲叠接,岩石圈中部拆离、滑脱、叠覆,盖层强烈褶皱和逆掩推覆。山脉上升、盆地下陷。中国东部燕山运动、西部喜马拉雅运动都达到全球陆内构造运动高峰。中国中、西部多期改造盆地和东部燕山期后新生盆地,将成为中国油气勘查的两大目标。  相似文献   

19.
Since 2006, we have conducted a geological exploration of the Khammuane area in southeastern Laos. Several thick sequences of potash deposits containing sylvite and carnallite were discovered from drilling Paleocene strata of the Thangon Formation (E1 tg). To constrain the origin of the brine that formed thick sequences of salt mineral deposits, we measured the strontium and boron isotope composition of some salt minerals in the potash deposit. Boron isotope composition of halite- and potash-associated minerals in the Khammuane potash deposit varied from 19.91% to 31.01‰, which differs significantly from continental evaporates (?6.83‰–?5.79‰) but is very close to that of salts precipitated from evapo-concentrated seawater (10‰–36‰). The 87Sr/86Sr ratios (0.707542 to 0.709461) of salts were also close to the values of Paleocene seawater (0.70772 to 0.707830). The content of Br? (0.01%–0.25%) and Br×103/Cl ratios (0.10–0.52) of halite were >10 times higher than that of common continental salts. These characteristics indicate clearly that the Laos potash deposits were deposited from seawater. The small variation in boron and strontium isotopes in all salt sedimentary sequences (gypsum-halite-potash-halite) also suggests that the recharge source should be stable and the effects of other continental water mixing are negligible. Large-scale potash deposits are commonly precipitated from seawater. Hence, the results of recent regional drilling work and geochemical research suggest extensive potash resources could occur in the Thangon Formation of southeastern Laos.  相似文献   

20.
The present paper deals with a tectonic event of Late Ordovician age affecting three blocks of China,i.e.South China,North China and Tarim.In the North China and the Tarim platforms,as well as their marginal belts,there was a regional uplift during the early Katian Stage of the Ordovician.The uplift was indicated by the unconformities between the Ordovician successions and overlying late Paleozoic strata.New biostratigraphic studies of conodonts and graptolites from many sections at Longxian and Yaoxian,North China shows that the youngest Ordovician strata are of the early Katian age corresponding to graptolite Diplacanthograptus spiniferus Biozone.The same level has been recognized to represent the uppermost Ordovician in the platform area of Tarim,whereas in the marginal belt the top boundary of the Ordovician is slightly younger,corresponding to the graptolite Dicellograptus complanatus Biozone.Thus,the regional uplift in North China and Tarim is shown by the disconformity between the early Katian strata and Late Paleozoic strata,the onset coinciding with that of the Kwangsian Orogeny in South China.The designation Kwangsian Orogeny later fell into disuse and was replaced by the term Caledonian Orogeny.However,in terms of geographic location,tectonic nature,and the timing of activity,the Caledonian Orogeny differs significantly from the orogenic event in South China,and the continued use of this term in South China is inappropriate and misleading.  相似文献   

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