共查询到20条相似文献，搜索用时 15 毫秒
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971349 Che;19 Jie(China Universityseienees,Beijing)The MammaljanShowjng ClimatieF盆uetuat应on—ExamPle of the Early Pleistoceneof Ge。FaunaS AS anMam-malian Faunas from Zhoukoudian,Beijing,China(ESI矛,ISSN 1 005一2321,CN 11一3370/P,4(2),1997,p·275一279,1 graph,1 table,10 ref) By analyses of the four local marnmalianfaunas from Zhoukoudian,Beijing,the EarlyPleistoeene elimatie and eeologieal environ-CN 11一1 905/Q1 53,1 graph,1735(2).1997,P.145一mental ehangespaper.One of1 .90M… 相似文献
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沿长江顺流而下,可以看到千山万谷,汹涌澎湃的三峡,也可以看到九曲回肠的荆江和潮平岸阔的江苏江段。在宜昌南津关,“山随平野尽,江入大荒流”(李白《渡荆门送别诗》)。长江就在这里由山区进入平原。一般说来,天然河流都可象长江一样,分为山区和平原两段。山区河流是水流改造山谷的产物。地壳运动,增加了河床演变的复杂性。山区河流具有下列特点:(1)河床纵比降大;(2)水流湍急紊乱;(3)山谷沿程宽窄不一,河道在平面上具有藕节状外形; 相似文献
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自然河流或者处于单向演变状态,或者处于准平衡状态。这是按平均概念而言。实际河床演变就是围绕这种均衡状态或正或负地交替进行。河流一旦受到外力干扰,均衡状态被破坏之后,河床演变过程也将随之改变。有的干扰、改变甚至破坏会很强烈。这种演变开始时都比较急剧,然后逐渐衰减,最终达到新的均衡状态。干扰河床演变均衡状态的途径有二:(1)改变河道的来水来沙条件。如河段以上的水土保持工程、拦沙工程、水库枢纽工程、分流堵汊工程和引水工程等的作用。它们增减水量、沙量,改变水流过程和输沙过程以及水沙搭配关系等。(2)改变河段河床形 相似文献
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采用最新的量子化学半经验计算方法MNDO－PM3，对作为粘土矿物结构基元的六元环分子体系进行了结构与能量的计算，揭示了结构变形的精确程度，并利用能量的差异大小，讨论了几种同分异构体的稳定性。 相似文献
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Yu Zuxiang Institute of Geology Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》1997,71(2):152-157
Malanite was first found in veinlets of disseminated copper-nickel ores inZunhua County, Hebei Province, and then in platinum-bearing chromite ores in ShuangfengVillage, Yanshan. In the former case, malanite appears as octahedrons or dodecahedrons asso-ciated with pyrrhotite, pentlandite, sperrylite and cooperite; while in the latter case, it is massiveor present in anhedral glomerocrysts, filling in cracks of iridisite and associated with osmiride,ferrian platinum and iridisite. Malanite is steel-grey in colour, opaque with metallic lustre andblack streaks and brittle with no magnetism. H_M=5.0, VHN_(20)=417kg/mm~2, cleavage {111}sometimes observed. The calculated density is 7.57g/cm~3. The reflective colour is white with alight green tint. Internal reflections are not observed. This mineral is isotropic, showing nobireflection or reflection pleochroism in air. By means of electron microprobe analysis, the em-pirical formula (based on 7 atoms) is expressed as (Cu_(0.93)Fe_(0.06))_(∑0.99)(Pt_(1.03)Ir_(0.66)Rh_(0.04)Pd_(0.03)Co_(0.20)Ni_(0.03))_(1.99)S_(4.03) or (Cu_(0.95)Fe_(0.07))_(∑1.02)(Pt_(1.37)Ir_(0.45)Co_(0.11)Rh_(0.08))_(∑2.01)S_(3.97). Five strongestlines (hkl, d, I) of X-ray powder diffraction data of malanite are 311,2.98(6); 400,2.48(5);333, 1.90(7); 440, 1.75(10); 731, 1.29(5). It was known on the basis of X-ray powder diffractiondata that malanite is cubic, and the space group is Fd3m with α=0.9940nm, V=0.9821(3)nm~3 and Z=4. The type material of malanite is deposited at the Geological Museum of China(GMC)s 相似文献
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戴橦谟 《矿物岩石地球化学通报》1984,(4)
本会同位素地球化学委员会K—Ar专业组,于1984年8月2日至6日在安徽屯溪召开了Ar~(40)-Ar~((?)0)计时技术讨论会。来自全国20个单位的36位代表出席了会议。该项新兴技术方法是将快中子活化与同位素质谱测定技术结合,对在不同加温条件下的同一个样品测定一组年龄(坪龄)。利用这种技术可以开展地质体的热史及其演化史的研究。与会代表非常感兴趣地听取了利用此法研究青藏高原、三江地区的板块碰撞热史和测定 相似文献
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20001589 He Chengquan(Naniing Instituteof Geology and palaeonrology,ChineseA-eademy of Seienees,Naniing,Jiangsu);SunXuekun Late Hauterivian Dinoflagellatesfrom the Lower Part of the Chengzihe For-mation in Jixi Basin,Eastern Heilongjiang,Northeast China(Aeta Palaeontologiea Sini-ea,ISSN 0001一6616,CN32一1188/Q,39(l),2000,p.46一62,1 illus.,2 tables,3Plates,67 ref) Chengzihe Formation 15 widely distribut-ed in eastern Heilongjiang Provinee.A totalof 22 dinoflagellate eyst taxa are… 相似文献
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980326 Chen Jianqiang(China University ofGeoseienees,Beijing)The MicroskeletalStruCtUreS ofM公k耐t勿LavruseviCh(Rugosa)(Aeta Palaeontologieal Siniea,ISSN 0001一6616,CN 32一1188,36(4),1 997,p.446一452,2 tables,2 Plates,18ref) Maikottia Lavrusevieh 1 967 15 a group ofPeeuliar fossil eystiPhyllids,usually in eerioideompound forms with eystiPhylloid septa eom-posed of eomposite rhabdaeanthines,rangingfrom Lower Silurian(Llandovery series)toUPPer Silurian(Ludlow series)in theYangtze … 相似文献
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1 937/P,30(4),1 995.p.321一328,2 graphs1 rable,8 ref,with English absrraer)962149 Yong Ruidong(In、titute of Geolo-gy,Guizhou Bureau of Geology and MineralResourees);Yang Chengxi THE CAR-BONIFEROUS TRACEF()SSILS INGUIZll0U:DISCUSSION ON DISTRIBU-TION OF ZOOPHYCOS THROUGHOUTGEOLOGIC HISTORY(GZG,ISSN 1000一5943,CN52一1059/P,12(4),1995,l,.290一297,2 graphs,1 plat。,1 2 rof) l’raee fossils臼rc abundant in fhe Cdr-bonlferous strata,esPeelally in those … 相似文献
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962135 Ma Yuzhen(The Deparrment of Ge-ograPhy,Lanzhou University,Lanzhou,730000);Tao Mingxin THE RED BEDSPORO一POLLEN ASSEMBLAGES ANDGEOLOGICAL AGE FROMZHUERZHUANG OF YAOJIE,GANSUPROVINCE(ASDS,ISSN 1000一0550,CN62一1038,13(4),1995,P.64一72,2graphs,1 table,1 plate,8 ref,with Englishabstraet)962136 Zhang Kexin(Faeulty of Earth Sei-enees,China Universiry of Geoseienees,Wuhan,卜Iubei,430074);Lai Xulong CON-ODONT SEQUENCE AND ITS GLOBALCORR… 相似文献
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962240 Li Ya(Fujian Provinee ExplorationCollege,Fuzhou,Fujian,350001)HYDRO-GEOLOGY AND ENGINEERING GEOLO-GY IN THE PROCESS COLLAPSE OF51,OPING FIELD GEOMORPHOLOGY(JCUES,ISSN 0253一6072,CN22一1151/P,25(4),1 995,p.428一434,2 graphs,4 ta-bles) ‘The distribution rule and formingmeehanism of land一slide and eollaPse indistriets where the railway,highway and hy-droeleetrie power sratio一1 were established,are summariedi:1 this paper.The at一thoreonsiders rhat … 相似文献
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目前所使用的显生宙(宇)各纪(系)的译名出处多样,说法不一。绝大部分译名出自日本学者在19世纪80年代音译或意译,少量译名由我国学者在民国初年直接翻译或修改日译术语而来,而"古近纪(系)"和"新近纪(系)"两个译名则在上个世纪90年代才由我国学者根据新的地层学成果译出。 相似文献
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980302 Feng Heng(块Partment of Earth Sci-enees,Nanjing University,Nanjing,J iangsu);Yang Xiangning Study on Taxono--my of Some PSeudOSchwageri加(FusulinidForamln三fera)(Aeta MieropalaeontologieaSiniea,ISSN 1000一0674,CN32一1189,14(3),1997,p.280一294,5 graphs,1 table,2 Plates,24 ref) Morphologieal measurements of 123 thinsections and sPeeimens Published in the litera-ture have been used to study the taxonomy of厂、6心oschwagerina“dd翻1 Dunbar et Skin-ner, 1 937,P.洲烤口ris(Scher肠… 相似文献
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刁飞一ISON WITH THOSE OF NEIGHBORINGAREAS(AMCS,ISSN 1000一0674,CN32一1 1 89,12(4),1995,p.349一373,2 graPhs,4tables,35 ref,wirh English abstraet)962146 Shang Ping(Fuxin Institute of Mi-n ing and‘I’eehnology,Fuxin,Liaoning)THE NATURE AND CHARACTERS OFTHE EARLY CRETACEOUS FLORAFROM THE PINGZHUANG BASIN,IN-NER MONGOLIA(GR,ISSN 0371一5736,CN 11一1 952/P,41(6),1995,P.533一536,1table,6 ref,with English abstraer)962144 Tong Guobang(Institute o… 相似文献
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