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1.
广西早泥盆世晚期至晚泥盆世的碳酸盐台地区发育有两个不同的四射珊瑚群落,此二群落都有其各具特点的珊瑚组合系列。其中,在开阔台地相区的四射珊瑚可划分为9个组合带,而在台地边缘相区则可划分为8个组合带。在早泥盆世早、中期,因岩相分异不明显,四射珊瑚仅可划分为3个组合带。因此证明,四射珊瑚的发展演化与沉积相演变有密切的关系。  相似文献   

2.
塔里木盆地西北缘阿合奇地区石炭系巴什索贡组研究程度较低,鲜有古生物化石的报道,其精确时代一直没有确定。在该套地层中发现四射珊瑚化石共计10属13种,床板珊瑚5属8种。其中四射珊瑚中主要分子有Kueichouphyllum,Palaeosmilia,Dibunophyllum,Arachnolasma,Lithostrotion,根据珊瑚的垂向分布,建立了Kueichouphyllum-Palaeosmilia-Dibunophyllum组合带,该组合带可与前人在华南地区早石炭世地层中建立的Yuanophyllum带进行对比,也能与邻区及中国其他地方相同时期的珊瑚组合对比,进而确定其精确时代为石炭纪密西西比亚纪维宪期至德坞期早期。对该珊瑚动物群的生物古地理研究表明,该动物群具明显的特提斯生物大区和中国北方大区的珊瑚分子特征,属二者的混生带。   相似文献   

3.
广西恭城地区的额头村组珊瑚化石极为丰富,自上往下共有20余层之多,共建立了Cystophrentis、Caninia dorlodoti及Ceriphyllum elegantum 3个珊瑚组合带,如此连续及完整的珊瑚组合带在广西同类地层中尚属首次发现.  相似文献   

4.
本文记述了产于四川龙门山地区中、上泥盆统界线附近观雾山组和土桥子组的四射珊瑚。在大量珊瑚标本鉴定的基础上,建立了中泥盆世晚期至晚泥盆世初期的四个四射珊瑚化石组合。根据四射珊瑚的演化规律,确定以Peneckiella珊瑚类的兴起和Pseudozaphrentis hejiazhaiensis,Temnophyllun(Truncicarinulum)beichua-nensis珊瑚类的消失作为龙门山地区识别中、上泥盆统界线的标志。  相似文献   

5.
本文以广西区域布格重力异常为主,结合其它地质资料,探讨了广西深部地质与成矿预测中的应用。认为:广西东部地壳为四层结构;河池一靖西重力梯级带是前寒武纪岩石圈断裂带,也是构成广西境内扬子地台与华南褶皱系的隐伏界线:右江重力高反映的局部幔隆,是右江裂谷系形成的地球动力基础:南岭重力低反映了多期次花岗岩化与陆壳增厚;总结了广西花岗岩15个岩带的空间展布和演化特征。还探讨了提取成矿预测信息的7条原则。  相似文献   

6.
泥盆纪-石炭纪右江盆地结构与岩相古地理演化   总被引:1,自引:0,他引:1  
右江泥盆纪─石炭纪沉积盆地是伴随着古特提斯洋的打开,在杨子古陆南部被动大陆边缘上逐渐发育形成的裂谷型盆地。在同沉积断裂活动的强烈影响下,形成以北西向为主,北东向次之的次级深水盆地与台地相间展布的岩相-构造格局。由于区域应力场和同沉积活动断裂带延伸方向的差异,使北西向次级深水盆地呈张裂性质的地堑式和半地堑式盆地,而北东向次级深水盆地则大都具走滑盆地特征。泥盆纪的岩相古地理演化可分为三个阶段,即初始裂陷阶段、被动陆缘裂谷作用阶段和沉积充填阶段。  相似文献   

7.
根据地层发育总面貌、沉积类型、古生物组合、变质作用以及地壳运动特点等因素综合考虑,河南地层区划可分为华北区和秦岭区两个一级区。其间以栾川—确山—固始深断裂带为界。本文所述北秦岭地层分区,北界与一级区一致,南界为内乡—桐柏—商城深断裂带。秦岭区内由于地质构造复杂,以往在不同区段划分的地层,划分方案各异,地层名称众多,很不统一。这对于研究秦岭地层、认识秦岭地质构造,造成很大困难。笔者等通过近年大区域的调查研究,提出了秦岭区地层统一划分方案。本文在该方案的基础上,着重讨论北秦岭地层分区前寒武系的划分,供深入研究秦岭地质参考。  相似文献   

8.
自从在东北南部发现早石炭沉积之后,笔者研究了该区下石炭统的分布、层型、沉积类型、岩相古地理、古生物及其地理分区等的特征,认为该区早石炭世沉积属地台型建造,由海陆交互相的陆源碎屑岩组成,形成了滨海—滨海沼泽环境,其沉积中心形成于氧化潮坪—泻湖环境。区内古生物组合明显具有欧美植物群和早期华夏植物群的色彩,与区域对比,可以独立划分古生物地理区。在此基础上,本文建立了一种新的早石炭世沉积类型——东北型和一个新的早石炭世古生物地理省——华北省,从而为中国早石炭世沉积特征、古生物及其地理分区以及岩相古地理等方面的研究提供了一些新资料和新的认识。  相似文献   

9.
广西有色地质勘查局勘查总院提交的《广西靖西县新圩铝土矿Ⅰ、Ⅱ、Ⅲ、Ⅳ号矿体群详查报告》和《广西靖西县新圩铝土矿Ⅴ、Ⅵ、Ⅶ号矿体普查报告》于 2月 9日通过了国土资源部储量评审中心评审。这标志着广西继平果铝土矿之后又探明 1个特大型铝土矿床。广西靖西县新圩铝土矿区处于右江褶皱带的南部 ,矿区面积 2 6 0km2 ,矿床类型为岩溶堆积型铝土矿 ,矿体分布于现代岩溶洼地内 ,并相对集中于 7个地段。该矿区地质勘查工作始于 1978年 ,2 0多年来广西有色地质勘查局 2 70队、2 74队、广西有色地质勘查总院等单位相继对该区进行了矿产调查…  相似文献   

10.
详细描述了西藏自治区改则县拉清乡汤模长二叠系剖面,自下而上划分为拉嘎组、昂杰组和下拉组。讨论了二叠系昂杰组和下拉组的岩性组合特征和沉积环境,其中昂杰组横向延伸不稳定向西相变尖灭。依据化石分布及组合特征,建立了Neoschwagerina-Chusenella conicocylindrica蜓组合带、Pachyphloia ovata-Eotuberitina reitlingerae非蜓有孔虫组合带、Lytvolasma asymetricum-Bradyphyllum caninoidia珊瑚组合带和Akagophyllum coqenense-Amplexocarinia muralis珊瑚组合带。昂杰组为早二叠世,下拉组下部为中二叠世栖霞期,而下拉组上部为中二叠世茅口期,并以暖水型气候环境为主。在昂杰组—下拉组中发现了珊瑚的2个新种和1个新亚种,并进行了描述。新种名称分别为Lophotabularia longiseptata sp.nov.和Iranophyllum longiseptatum sp.nov.,新亚种名称为Cyathocarinia tuberculata multiseptata sub sp.nov.。  相似文献   

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12.
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   

13.
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   

14.
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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16.
《山地科学学报》2014,(4):I0004-I0009
<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet.  相似文献   

17.
<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by  相似文献   

18.
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   

19.
Using the NCEP/NCAR reanalysis monthly 500 hPa height data on a 2.5 latitude-longitude grid and 1°×1° sea ice data,the polar vortex area,intensity index and arctic sea ice area index are calculated respectively,and the meridional distribution,period variation and the abrupts in the long range trend are analyzed to study their relationship.The results show that the meridional distribution of sea ice and polar vortex h-ave distinctive difference,the relative positions of them are different in the eastern and western hemispheres,and exept they have periods of 4 months,quasi half year,quasi year,4-5 years and 10 years commonly,and each of them has its own respective variation as well.The sea ice area is decreasing apparently since 1980's,so is the polar vortex area,but their abrupt changge time are different totally.The area of sea ice and polar vortex has prominent positive correlation,but the relationship of sea ice intensity,polar vortex intensity,polar vortex area is complicated.  相似文献   

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