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evolution of these fusulinaceans. Nine levels inthis undisturbed section were selected to describethe fusulinacean fauna. A new species,Triticites? leciae, is described from the top of thesection. The vertical distribution of this faunapoints to the presence of both the Protriticitesand the Montiparus Zones which in the RussianPlatform form the C 3 A Zone (Krevyakinskyand Khamovnichesky horizons). A level correspondingto the North American Desmoinesian/Missourianboundary lies either in thehigher part of the Montiparus Zone, near the topof the section, or slightly lower, but still abovethe underlying Protriticites Zone. The formertraditional Middle/Upper Carboniferous boundaryof Eurasia could be a major biostratigraphicboundary that coincides with a level of importantfaunal change. It is at about this level that thelate fusulinellid Protriticites (including speciesgroups commonly assigned to Praeobsoletes andObsoletes) evolved from different species groupsof Fusulinella. However, the evolutionarychange from Fusulinella to Protriticites, andthen to the earliest schwagerinid Montiparus,was quite gradual and may have started in olderstrata containing distinctly Middle Carboniferousfusulinaceans. No rapid turnover of the fusulinellid/schwagerinidfauna occurs near thatboundary. The minimal morphological divergenceinvolved in the evolution from Fusulinellato the late fusulinellids does not justify the recognitionof three genera (i.e. Protriticites, Obsoletes,and Praeobsoletes). For this reason, andalso in view of the practical difficulties with regardto their distinction, the genus Protriticites isredefined here to include the other two genera.2008040286美 国 加 利 福 尼 亚 北 部 Calera 灰 岩 白 垩 纪 浮 游有 孔 虫 的 生 物 地 层 学 = Cretaceous plankticforaminiferal biostratigraphy of the CaleraLimestone, Northern California, USA. ( 英 文 ).Sliter W V. Journal of Foraminiferal Research,1999, 29(4): 318-339 4 图 版 .The Calera Limestone is the largest, moststratigraphically extensive limestone unit of oceaniccharacter included in the Franciscan Complexof northern California. The aim of this paperis to place the Calera Limestone at its typelocality (Rockaway Beach, Pacifica) in a highresolutionbiostratigraphy utilizing planktic foraminifersstudied in thin section. A section,about 110 m-thick, was measured from the middlethrust slice exposed by quarrying on thesouthwest side of Calera Hill at Pacifica Quarry.Lithologically, the section is divided in two units;a lower unit with 73m of black to dark-greylimestone, black chert and tuff, and an upper unitwith 36.8m of light-grey limestone and mediumgreychert. Two prominent black-shale layersrich in organic carbon occur 11 m below the topof the lower black unit and at the boundary withoverlying light-grey unit, yielding a total organiccontent (TOC) of 4.7% and 1.8% t.w., respectively.The fossiliferous Calera Limestone sectionmeasured at Pacifica Quarry, from the lowerblack shale, contains eleven zones and threesubzones that span approximately 26 m.y. fromthe early Aptian to the late Cenomanian. Thezones identified range from the Globigerinelloidesblowi Zone to the Dicarinella algerianaSubzone of the Rotalipora cushmani Zone.Within this biostratigraphic interval, theTicinella bejaouaensis and Hedbergellaplanispira Zones at the Aptian/Albian boundaryare missing as are the Rotalipora subticinensisSubzone of the Biticinella breggiensis Zone andthe overlying Rotalipora ticinensis Zone in thelate Albian owing both to low-angle thrust faultingand to unconformities. The abundance andpreservation of planktic foraminifers are poor inthe lower part and improve only within the upperG. algerianus Zone. The faunal relationship indicatethat the lower black shale occurs in theupper part of the G. blowi Zone and correlateswith the Selli Event recognized at global scale inthe early Aptian. The upper black shale occurs ator near the boundary between the G. ferreolensisand G. algerianus Zone in the late Aptian. Thisblack layer, or Thalmann Event as named here,seems to represent the sedimentary expression,at the scale of Permanente Terrane, of a globalperturbation of the carbon cycle.2008040287北 大 西 洋 亚 热 带 区 Cenomanian-Turonian 界线 的 有 孔 虫 组 合 和 稳 定 同 位 素 变 化 = Foraminiferalassemblage and stable isotopicchange across the Cenomanian-Turonian boundaryin the subtropical North Atlantic. ( 英 文 ).Huber B T; Leckie R M. Journal of ForaminiferalResearch, 1999, 29(4): 392-417 3 图 版 .The Cenomanian/Turonian boundary interval(CTBI) at Site 1050 (30 degrees 6'N, 76 degrees14'W) was investigated to characterize climaticand oceanographic changes during the OceanicAnoxic Event that was associated with it (OAE2). Because of unusually good foraminiferalpreservation for sediments of this age, we haveobtained an unaltered oxygen and carbon isotopeprofile and an accompanying record of plankticand benthic foraminifer abundance changesacross the OAE 2 interval. Biostratigraphic,sedimentologic, and chemostratigraphic analysesindicate that more than 0.5 m.y. between theonset and tail end of OAE 2 are missing. Thisexplains why organic-rich sediments are absentfrom the Site 1050 sequence and why the plankticand benthic carbon isotope shifts are minor( approximately 0.8 per mil) compared with the93