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graphy and Geological Correlation, 2007, 15(3):267-276The work is aimed at litho-, bio- and magnetostratigraphicsubdivision of the Middle-UpperJurassic sedimentary succession in the northeastof the Ul’yanovsk-Saratov depression (the EastRussian plate). Problems of regional and interregionalcorrelation of distinguished subdivisionsare considered. As is shown, the ammonite biostratigraphyis most effective method for solvingproblems of chronostratigraphy.2008040540根 据 磁 性 地 层 学 和 生 物 地 层 学 对 北 方 区 - 特 提斯 区 侏 罗 纪 - 白 垩 纪 界 线 之 间 对 比 = Borealtethyancorrelation of the Jurassic-Cretaceousboundary interval by magneto- and biostratigraphy.( 英 文 ). Houša V; Pruner P; Zakharov V A.Stratigraphy and Geological Correlation, 2007,15(3): 297-309As a result of detail sampling and paleomagneticstudy of the 27-m-thick section of Jurassic-Cretaceous boundary beds in the Nordvik Peninsula(Anabar Bay, Laptev Sea), a succession ofM-zones correlative with chrons M20n-M17r isestablished for the first time in the Boreal deposits.Inside the normal polarity zone correspondingto Chron M20n, a thin interval of reversedpolarity, presumably an equivalent of the KysucaSubzone (M20n.1r), is discovered. The otherthin interval of reversed polarity establishedwithin the next normal polarity zone (M19n) iscorrelated with the Brodno Subzone (M19n.1r).The same succession of normal and reversedpolarity zones has been discovered recently inthe Jurassic-Cretaceous boundary beds of theTethyan sections: in the Bosso Valley (Italy), atthe Brodno (Slovak Republic) and Puerto Escaño(Spain) sites. Correlation of successionsestablished lead us to conclusion, that the Jurassic-Cretaceousboundary corresponds in thePanboreal Superrealm to a level within theCraspedites taimyrensis Zone of the upper VolgianSubstage. Hence, the greatest part of VolgianStage should be included into the JurassicSystem. Biostratigraphic data do not contradictthis conclusion.2008040541俄 罗 斯 伏 尔 加 中 部 地 区 古 新 世 末 期 的 生 物 地层 和 古 环 境 = Terminal paleocene of the Volgamiddle reaches: Biostratigraphy and paleosettings.( 英 文 ). Oreshkina T V; Aleksandrova G N.Stratigraphy and Geological Correlation, 2007,15(2): 206-230Diatoms and marine palynomorphs from severalsections of the Kamyshin Formation (Sengilei-1,Sengilei-2, Balasheika, Kuz’kino, boreholes38 and 50) are jointly studied for the firsttime in the Volga middle reaches. According toresults, the formation lower part correspondshere to Viborg Zone 4-Viborg Zone 5 (Heilmann-Clausen,1985)/Alisocysta margarita(part)-Apectodinium hyperacanthum (Powell,1992) diatom zones of Northern Europe. Higherlevels of the formation are correlative with Trinacriaventriculosa and Hemiaulus proteus dinocystzones (Strelnikova, 1992). Thus, the Kamyshinsedimentary cycle in the Volga middlereaches corresponds to the interval of NP8 (part)and NP9 zones of the general scale. As is established,different terrigenous to siliceous facies ofthat cycle (sands, diatomites, opokas and clay)are mostly confined to eastern and southeasternareas of the study region. Judging from taxonomiccomposition, assemblages of diatoms andmarine palynomorphs originated in coastal paleosettingswith active hydrodynamics and highproductivity of water mass. Diatom assemblagesfrom different facies are dissimilar. Three phasesof Thanetian transgression are distinguishedbased on quantitative proportions of differentecologic groups (Paralia/Pyxidicula ratio variations).Within transition from the Trinacria ventriculosato Hemiaulus proteus Zone, there arerecorded considerable changes in composition ofdiatom assemblages: the appearance of new generawith considerable morphologic innovations(Podosira, Craspedodiscus, Fenestrella, Moisseevia,Solium, Gyrocylindrus) and compositionalrenewals of genera Pyxidicula, Trinacria,and Hemiaulus. These changes are indicative ofa global biotic crisis in the Paleocene-Eocenetransition related with thermal maximum andnegative C-isotope excursion and extinction ofbenthic fauna groups.2008040542大 型 浅 水 泥 质 缓 坡 的 古 环 境 、 古 地 理 和 自 然地 理 : 西 加 拿 大 陆 前 盆 地 晚 赛 诺 曼 期 - 土 仑 期Kaskapau 组 = Palaeoenvironments, palaeogeography,and physiography of a large, shallow,muddy ramp: Late Cenomanian-TuronianKaskapau Formation, Western Canada forelandbasin. ( 英 文 ). VARBAN B L; PLINT A G.Sedimentology, 2008, 55(1): 201–233The Kaskapau Formation spans Late Cenomanianto Middle Turonian time and was depositedon a low-gradient, shallow, stormdominatedmuddy ramp. Dense well log control,coupled with exposure on both proximal anddistal margins of the basin allows mapping ofsedimentary facies over about 35 000 km 2 . Thestudied portion of the Kaskapau Formation is amudstone-dominated wedge that thins from700 m in the proximal foredeep to 50 m near theforebulge about 300 km distant. Regional floodingsurfaces permit mapping of 28 allomembers,each of which represent an average of ca 125 kyr.164