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1.
陈蔡群原岩的主体形成于大洋岛弧环境,由拉斑玄武岩和同源辉长岩,碳酸盐岩和浊流沉积的泥砂质碎屑岩组成;经受了中压角闪岩相区域动力—热流变质作用和多期褶皱变形;岩石地球化学和同位素年代资料表明,中国东南的威尔逊旋回在中元古晚期便已开始,即那时于扬子古陆与华夏地块之间存在一大洋盆地,洋壳上可能存在拉张期残留的花岗质陆壳碎块。中元古晚期开始了洋壳消减作用及其有关的火山—沉积作用,新元古晚期陈蔡大洋岛弧地体与双溪坞陆弧地体拼贴、碰撞,壳体间的聚合作用触发了陈蔡群岩石的变质、变形。  相似文献   

2.
辽宁省辽河群孔达岩系分在于营口-草河口复向斜南北两翼,主要由各类片岩、变粒岩、片麻岩夹斜长角闪岩、大理岩组成,为高绿片岩相和低角闪岩相,原岩属碳酸盐岩富碳的陆源碎屑-粘土沉积建造。孔达岩系中石墨稳定同位素研究表明,石墨与有机墨有关,可能来源于低等生物;沉积时期的古气候为温湿-亚热带,沉积物质来源于海底火山喷发和陆源碎屑,沉积环境为浅海微淡化水体,低能、强还原环境的泻湖相。  相似文献   

3.
辽南鞍山群岩石类型主要为片麻岩类、斜长角闪岩类。原岩是中基性火山岩,中酸性凝灰岩及硅铁质沉积岩,属含硅铁质沉积岩的中基性火山—沉积岩建造。根据原岩建造分析。辽南地区地壳早期演化特点力:大约2800Ma前海底火山活动强烈,以基性岩浆喷发为主。其后,以中基性岩浆喷发为主。在喷发间歇期间有沉凝灰岩的出现。大约在2800Ma 后的鞍山运动第一幕,使本区隆起上升,缺失上鞍山群堆积。辽南鞍山群低角闪岩相岩石属正常区城变质成因的片麻岩,原岩是火山岩和火山—沉积成因的层状表壳岩。其原岩组合特点不同于某些典型地区的绿岩带,不代表原始地壳,是后期为岛弧—海沟带火山和沉积作用的产物。  相似文献   

4.
本文对陈蔡群变质岩中的斜长用闪岩进行了地球化学研究。常量元素、微量元素和稀土元素的特征表明陈蔡群变质岩中存在两种不同成因的斜长角闪岩,其一是正角闪岩,由拉斑玄武质岩石变质形成;其二是副变质成因的角闪岩,其原岩为白云质泥灰岩。进一步的地球化学研究,揭示出正斜长角闪岩的成岩构造环境类似于大陆边缘环境。  相似文献   

5.
胶北隆起新建荆山群,处于胶东群之上,暂置于粉子山群之下;为一套不稳定至半稳定型浅海相陆源碎屑(底部有少量火山碎屑)夹碳酸盐岩的类复理石建造,经过多期变质作用达到角闪麻粒岩相的变质沉积岩系。变质矿物共生组合和各世代矿物的相互关系显示该套岩系经历了四期变质作用。单矿物化学成分及地质温压计等定量估算出各期变质作用的P—T条件: 第一期变质作用相当于角闪麻粒岩相条件,t=780~817℃,p=0.5GPa±,fo_2=10~(-15.5) 第二期变质作用相当于高角闪岩相条件,t=630~690℃,p=0.4GPa±。第三期变质大致为低角闪岩相,t=525℃±。第四期变质相当于绿片岩相条件,t<400℃。  相似文献   

6.
河南临汝安沟地区前嵩山群变质矿物、变质矿物组合以及变质温压条件研究表明,前嵩山群分属不同的变质建造,其中安沟群属中压相系绿片岩相变质作用,登封群头道河组为中压相系角闪岩相。同时,两套地层变质作用之间缺少钠长—绿帘角闪岩相,这一变质作用的间断,从一个侧面反映了地层的间断。  相似文献   

7.
根据佛坪地区广泛出露的一套副变质岩系的岩石组合、矿物组合、变质相特征和岩石地球化学特征的分析,认为它们是一套中深变质的碎屑岩-泥质岩-碳酸盐岩建造。原岩形成于相对稳定的大陆边缘-微板块内的陆表海环境。经过角闪岩相区域变质作用,形成了佛坪地区较为完整的孔兹岩系  相似文献   

8.
通过对胶北臧家庄盆地中生代火山岩系的构造位置、产出状态、岩石特征、地球化学特征、相序列组合及同位素年龄等资料的综合分析,结合区域构造特征,认为其属中国东部中生代火山岩带之桃村—莱阳火山 沉积盆地构造组成部分;岩石类型为玄武岩、安山岩、英安岩及流纹岩等,属钙碱性系列,按相序列可划分为安山质岩系、英安质岩系及凝灰质粘土岩三个相组;构成两个火山旋回。  相似文献   

9.
辽宁西部地区中生代白垩纪存在两期火山旋回,时代分别属早白垩世早期和中白垩世早期。早白垩世火山旋同即义县组,中白垩世火山旋回本文称为大兴庄火山岩,该期火山岩火山活动微弱,火山岩分柑局限,主要出露于阜新—义县盆地的东侧上齐台一带,以宁静的侵出和次火山岩侵入为主,是早白垩世阜新组沉积之后,中白垩世孙家湾组沉积之前的一次火山活动,它与孙家湾组共同组成一个火山喷发—沉积旋回。  相似文献   

10.
辽南金州地区的太古宙侵入岩   总被引:2,自引:0,他引:2  
辽南金州地区的太古宙变质侵入岩,是由得胜片麻杂岩为代表的早期TTG岩系和由亮甲店片麻岩、小黑山片麻岩及赵屯片麻岩组成的晚期石英闪长岩—低硅英云闪长岩—花岗岩系构成的,早期岩系呈奥长花岗岩演化趋势,晚期岩系显钙碱性演化趋势,属太古宙常见的两类岩石系列,其源岩来源陆壳,是陆壳角闪岩或石榴角闪岩部分溶融的产物。  相似文献   

11.
12.
The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature.  相似文献   

13.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprehensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose  相似文献   

14.
<正>Copyright Submfnion of a roanusatpt inks:that the work described has not been published before(exoept In the form of an abstrW or as part of a published lecture,review,or thesis);that it is not under consideration for publication elsewhere that its publication has been approved by ail  相似文献   

15.
<正>The Journal of Ocean University of China(Oceanic and Coastal Sea Research)is a comprehensive academic quarterly sponsored by the Ocean University of China,published one volume per year.This journal is devoted to the publication of the theoretical and applied research results on oceanography and marine fisheries.The fieldcovered include the physical,chemical,biological,geo-  相似文献   

16.
<正>The 35th IAHR World Congress was held in Chengdu,China from September 8 to September 132013.The title of the conference was:"The Wise Finds Pleasure in Water:Meandering through Water Science and Engineering".During the congress,1239 papers were presented in 139sessions for oral presentations and 7 sessions for poster presentations.After the Congress,a Committee was appointed to select some of the best papers presented at the Congress for publication,after a  相似文献   

17.
As an important component of the cryosphere,sea ice is very sensitive to the climate change.The study of the sea ice physics needs accurate sea ice thickness.This paper presents an electromagnetic-induction(EM) technique which can be used to measure the sea ice thickness distribution efficiently,and the successful application in Bothnian Bay.Based on the electromagnetic field theory and the electrical properties of sea ice and seawater,EM technique can detect the distance between the instrument and the ice/water interface accurately,than the sea ice thickness is obtained.Contrastive analysis of the apparent conductivity data obtained by EM and the value of drill-hole at same positions allows a construction of a transformable formula of the apparent conductivity to sea ice thickness.The verification of the sea ice thickness calculated by this formula indicates that EM technique is able to get reliable sea ice thickness with average relative error of only 12%.The statistic of all ice thickness profiles shows that the level ice distribution in Bothnian Bay was 0.4-0.6 m.  相似文献   

18.
Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.  相似文献   

19.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.  相似文献   

20.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied  相似文献   

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