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1.
贵州台江早、中寒武世凯里组的遗迹化石   总被引:13,自引:3,他引:13  
杨式溥 《古生物学报》1994,33(3):350-358
凯里组发现遗迹化石9属14种,主要是以PhycodespedumSeilacher为主的遗迹群落,重要的遗迹属如:Cochlichnus,Gordia,Monomorphichnus,Oldhamia,Planolites,Treptichnus等常见于世界各地寒武纪Cruziana遗迹相。根据遗迹化石表明凯里组沉积于盐份、含氧量正常,海水能量中等的浅海软基底潮下带环境。  相似文献   

2.
《生理通讯》2002,21(6):173-178
第一条 本学会的中名称为中国生理学会,英译名Chinese Association for Physio1ogical Sciences,缩写为CAPS。  相似文献   

3.
西藏南部白垩系及下第三系的生物相及遗迹相   总被引:3,自引:1,他引:2  
西藏南部地区是我国海相白垩系—下第三系发育最好的地区之一,对这套地层的生物相和遗迹相研究,有助于了解印度板块和欧亚板块碰撞前这一地史时期该地区的沉积环境和古地理面貌。文章描述了5个生物相组合包括24个主要的生物相类型和4种主要的遗迹相(Nereites,Zoophycos,Cruziana和Skolithos遗迹相),其中Zoophycos遗迹相进一步划分出Thalassinoides-Planolites遗迹亚相和Zoophycos-Chondrites遗迹亚相,它们在剖面中交替出现,与原始沉积环境的含氧条件变化有关。  相似文献   

4.
长江下游三叠系青龙组遗迹化石   总被引:3,自引:0,他引:3  
记述了长江下游一带由灰岩为主组成的下三叠统青龙组中的遗迹群。其中至少包括有37个遗迹属,以水平潜穴占优势,并伴有垂直潜穴、拖迹(trail)、足迹(track)和停息迹等各种类型的痕迹。其中常见分子有Planolites,Chondrites,Palaeophycus,Phycodes以及Arenicolites,Monomorphichnus等。它们应属于Cruziana遗迹相范畴。文中阐述和讨论了它们的时空分布状况以及形成的环境,系统描述了这个遗迹群中的31个遗迹属和31个遗迹种,包括4新属5新种。  相似文献   

5.
NaturalMedicineInformation(MedicalJournalWatch :AbstractandComments)L CarnitineImprovesExerciseToleranceAmongAnginaPatientslyerRN ,KhanAA ,etal.L carnitinemoderatelyimprovestheexercisetoleranceinchronicstableangina .JAssocPhysIn dia 4 8(11) :10 5 0~ 10 5 2 ,2 0 0 0 .Forty s…  相似文献   

6.
L CarnitineImprovesExerciseToleranceAmongAnginaPatientslyerRN ,KhanAA ,etal.L carnitinemoderatelyimprovestheexercisetoleranceinchronicstableangina .JAssocPhysIn dia 48(11) :10 5 0~ 10 5 2 ,2 0 0 0 .Forty sevenmenandwomenaged 48to 6 4yearswhohadchronicstableanginatook 2gofL car…  相似文献   

7.
L CarnitineImprovesExerciseToleranceAmongAnginaPatientslyerRN ,KhanAA ,etal.L carnitinemoderatelyimprovestheexercisetoleranceinchronicstableangina .JAssocPhysIn dia 4 8(11) :10 5 0~ 10 5 2 ,2 0 0 0 .Forty sevenmenandwomenaged 4 8to 6 4 yearswhohadchronicstableanginatook 2 gofL c…  相似文献   

8.
描述我国西藏南部堆纳地区宗山组下部及基堵拉组中的遗迹化石。宗山组中的遗迹化石组合可归属于Zoophycos遗迹相,该遗迹相可进一步划分产于富氧条件下的Thalassinoides-Planolites遗迹及产于贫氧条件下Zoophycos-Chondrites遗迹亚相。基堵拉组中的遗迹化石组可归属于在高能的潮下带的临滨和潮间带的前滨环境下产生的Skolithos遗迹相。  相似文献   

9.
应用生态学报第5卷(1994)关键词索引CHINESEJOURNALOFAPPLIEDECOLOGYVol.5(1994)KEYWORDINDEXAAcanthopanaxsenlicosusigloo5(3):237Agroecosystem¥k4...  相似文献   

10.
Trichosanthin(TCS)isanimportantmemberofribosomeinactivatingproteins[1].ItpossessesNglycosidaseactivityremovingadenine(ADE)atpositionA4324of28SrRNA[2].TheactivepocketofNglycosidasehasbeenestablishedthroughthecrystalstructuresofTCS,αMMCandricinandassayofmutants…  相似文献   

11.
青海曲麻莱-治多地区巴颜喀拉山群(上三叠统)遗迹化石   总被引:3,自引:0,他引:3  
首次对青海南部曲麻莱-治多地区巴颜喀拉山群上部(上三叠统)遗迹化石进行了系统采集,共采获遗迹化石33属54种。据遗迹化石的形态、习性、水深等环境成因特征,可划分为两类组合:一类以Cosmorhaphe,Helminthopsis,Helminthoida,Megagrapton,Paleodictyon等为主,产生于浊流事件前;另一类以Chondrites,Neo-nereites,Palaeophycus,Phycosiphon,Planolites,Zoophycos等为主,产生于浊流事件后,两者均为半深海-深海Nereites遗迹相的典型代表,反映晚三叠世研究区应为浊流沉积发育的复理石相沉积。  相似文献   

12.
龚一鸣 《古生物学报》2001,40(2):177-188
在天山志留系,石炭系和东昆仑-西秦岭三叠系浊积岩系中遗迹化石发育,经研究计有:Helminthopsis hieroglyphica,Neonerietes biserialis.,N,uniserialis,palaeophycus isp.,P.serratus,P.striatus.P.tubularis,Paleodictyon imperfectum,Phycodes circinnatum,Phycosiphon incertum,Planolites annularis,P.beverleyensis,P.Montanus,Rhizocorallium ips.,Scalarituba missourensis,Skolithos ips.,?Spirorhaphe isp.,sublorenzinia ips.Tambia isp.,Taphrhelminthopsis auricularis,Teichichnus isp.,Thalassinoides isp.它们构成4种遗迹化石组合:Phycosiphon-Palaeophycus组合,Neonereites-Scalarituba组合,Paleodictyon组合和Phycodes Skolithos组合,分别代表局限缺氧深海盆地浊流沉积,半深海环境中-上扇沉积,多岛洋环境的中-下扇沉积,半深海环境的中扇浊流沉积。  相似文献   

13.
During the Triassic, the Bayan Har Basin is a huge triangular basin surrounded by the North China Platform, South China Platform and Qingtang Terrane. It is filled by a Triassic turbidite sequence, the Bayan Har Group. For a long time, the series of Bayan Har Group in the eastern part of the basin were considered to be a Lower to Upper Triassic sequence, and in the western part, was attributed to the Upper Triassic. A well-preserved diversified radiolarian fauna was recovered from radiolarian chert and tuffite interbeds of the Bayan Har Group turbidites and adjacent stratigraphic units in the Hoh Xil area, northern Tibet. Sixty-seven species are identified and subdivided into two assemblages: late Anisian and early Carnian. Combined with the discovery of the Late Permian and Early Triassic turbidite in the Bayan Har Group in this area by Huang et al., it proves that all the Triassic is also present in the Bayan Har Group sequence in the western part. The evolution of the Bayan Har Basin may be traced back to the Late Permian. The massive sequence of the Bayan Har Group and its provenance indicate that the Kunlun and Qinling orogenic belts rapidly rise during the Middle-Late Triassic. The basin extended to the end of the Triassic, possibly locally to the Jurassic.  相似文献   

14.
金沙江上游两岸为川西、藏东地区。此区的四川省白玉县、西藏贡觉县及江达县的晚三叠世诺利期沉积中发现了有孔虫18属21种,海参骨片5属8种。三叠纪海参在中国为首次报道:白玉县及贡觉县的三叠世有孔虫也为首次发现。这一动物群在区域地质史及古地理研究上具有一定意义。  相似文献   

15.
Robert Metz 《Ichnos》2020,27(2):142-151
Abstract

Fluvial deposits of the uppermost Stockton Formation (Late Triassic), Newark Basin, west-central New Jersey have yielded an assemblage of trace fossils. Dominated by burrows, specimens include Cochlichnus anguineus, Helminthoidichnites tenuis, Planolites beverleyensis, Scoyenia gracilis, Spongeliomorpha carlsbergi, Treptichnus bifurcus, Treptichnus pollardi, plant remains, and an undetermined vertebrate trace fossil. The assemblage belongs to the Scoyenia ichnofacies. On the basis of stratification and primary sedimentary structures, the beds are interpreted as deposits in a meandering stream environment. Larval insects, wormlike forms, and arthropods are probably responsible for most of the animal traces in wet or moist channel, floodplain, and point bar sediments subject to subaerial exposure.  相似文献   

16.
Summary During the Middle and early Late Triassic carbonate ramps and rimmed platforms developed at the northwestern margin of the Tethys ocean. In the Northern Calcareous Alps, Anisian stacked homoclinal ramps evolved through a transitional stage with distally steepened ramps to huge rimmed platforms of Late Ladinian to Early Carnian age. Middle Triassic to early Late Triassic facies and biota of basin, slope and platform depositional systems are described. Special emphasis is given to foraminifers, sponges, microproblematic organisms and algae. The Ladinian to early Carnian reef associations are characterized by the abundance of segmented sponges, microproblematica, biogenic crusts and synsedimentary cements. Among the foraminifers, recifal forms likeHydrania dulloi andCucurbita infundibuliformis (Carnian in age) are reported from the Northern Calcareous Alps for the first time. Some sphinctozoid sponges likeParavesicocaulis concentricus were known until now only from the Hungarian and Russian Triassic.  相似文献   

17.
The Sulu Sea in the western equatorial Pacific is presently a shallowly-silled, dysaerobic, deep-marine basin. Deep waters in the Sulu Sea are ventilated through a single sill at 420 m depth which connects it to the China Sea. Benthic and planktonic foraminiferal oxygen and carbon isotope records, benthic and planktonic foraminiferal census data and total organic carbon measurements have been used to evaluate changes in water mass conditions in the Sulu Sea between the last glacial maximum (18,000 yrs. B.P.) and the present day.An increase in the abundance of the planktonic foraminiferaNeogloboquadrina dutertrei and relatively light planktonic foraminiferal δ18O values suggest that during the last glacial maximum surface water salinities were reduced in the Sulu Sea. Enhanced isolation of the basin due to glacio-eustatic lowering of sea level and reduced surface salinities resulted in stagnation of deep water and an expansion of the mid-water oxygen minimum layer. Increased organic carbon preservation at mid-water depths occurs at this time. Benthic carbon isotope data and an increase in the abundance of benthic foraminiferal species considered to prefer low oxygen environments support the conclusion of an oxygen-minimum expansion at mid-water depths during the last glacial maximum. At water depths greater than 4000 m, bottom waters appear to have maintained some degree of oxygenation during the last glacial maximum. Stronger Pacific Ocean trade winds at this time may have caused the influx of denser Celebes Sea surface water into the southern part of the Sulu Sea. The slow sinking of this water would have then ventilated bottom waters in this part of the basin.At the transition from glacial to interglacial conditions, rising sea level caused denser water to flow over the deepest sill into the Sulu Sea. Vertical circulation increased, resulting in a greater downward flux of oxygen and a dissipation of the oxygen minimum. Continued post-glacial sea level rise caused periodic ventilation of deep water until the present dysaerobic conditions were established.  相似文献   

18.
19.
吴贤涛 《古生物学报》2005,44(4):599-610
河口湾砂岩储层,在下切谷型油气勘探类型中极具潜在经济价值,因而引起众多沉积环境研究者的关注。河口湾是河水、海水相互作用的场所,具明显的三重沉积结构,即在河口湾内侧,河流淡水沉积具主导;在河口湾外侧,则以潮汐或波浪等海水水流沉积占优;而河口湾的中央地带,是海水和淡水汇合区,表现出咸水水体和低能环境的沉积特征。东濮凹陷沙河街组四段,低位期形成的下切谷和高位期转变成河口湾的过程,由沉积柱子中的海水生物痕迹、咸水生物痕迹及淡水生物痕迹记录下来,这些适应于不同水体的造迹生物所留下的痕迹,弥补了这一地区缺乏标志性实体化石带来的认识障碍,为识别其沉积环境真面目找到了新途径。由Cylindricum-Scoyenia为代表的淡水痕迹化石组合,以Tigillites和喜盐植物根迹为代表的咸水生物痕迹和以Thalassinoides,Teichichnus为代表的海水生物痕迹,在东濮凹陷沙河街组四段钻取的岩芯中多次出现,证实了那里河口湾沉积的三重结构和下切谷的存在。  相似文献   

20.
William Miller III 《Ichnos》2013,20(3):161-171
Dissection of fine‐grained turbidites within the Franciscan complex at Trinidad Harbor reveals intrastratal zonation of biogenic structures. The pre‐depositional association comprises only three ichnotaxa (preserved in convex hyporelief) and is less diverse than the tiered post‐depositional association (comprised by at least seven ichnotaxa preserved in full relief). The latter association is dominated by Melatercichnus (n. ichnogen.). Post‐depositional trace‐makers exploited abundant plant detritus deposited with the turbidite sand. Temporal alternation of trace fossil associations resulted from the infrequent, but catastrophic, disturbance of pre‐turbidite communities and local replacement by assemblies of opportunistic organisms. Although probably short‐lived at specific sites, the post‐turbidite infauna was tiered, enabling a variety of deposit feeders to harvest phytodetritus of varied size or density simultaneously at different depths within newly deposited turbidite sand layers.  相似文献   

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