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able problems, particularly different opinions ona role of lithostratigraphy and on the GSSP conceptare discussed.2008040500地 层 学 : 通 往 地 质 历 史 和 生 物 历 史 的 途 径 =Stratigraphy: gateway to geohistory and biohistory.( 英 文 ). McGowran B; Li Qianyu. Stratigraphy,2007, 4(2/3): 173-185Concerned with the ordination, correlationand age determination of the rock record and theevents entombed therein, stratigraphy is the centraldiscipline in geohistory and biohistory. Weconsider (from our Cenozoic perch) changes instratigraphy since the gestation of the InternationalStratigraphic Guide—changes in responseto the “revolutions” of plate tectonics, bolidetheory, sequence stratigraphy and cyclostratigraphy,and a cultural shift away from Lyelliangradualism. We discuss certain strictly stratigraphicmatters in terms of the “Hedberg triad”of lithostratigraphy, biostratigraphy andchronostratigraphy, which triad has had its dayas the core structure of the Guide. Sequencestratigraphy challenges both the lithostratigraphicformation and the notion of pervasivediachrony. Biostratigraphy flourishes in both itsoppelzone and phylozone modes and is integratedincreasingly with geomagnetic (the Cenozoicspine) and radiometric evidence in a sequence-andcyclostratigraphic context.Chronostratigraphic classification is hierarchicalbut rigid nesting is questioned.2008040501进 入 21 世 纪 的 地 层 学 = Stratigraphy into the21st century. ( 英 文 ). Carter R M. Stratigraphy,2007, 4(2/3): 187-19319th and 20th century stratigraphy often concerneditself primarily with classification andnomenclature, during what can be termed theheroic and codex ages of stratigraphy. In contrast,21st century stratigraphy will fall withinthe post-modern age. In possession of agreedclassification schemes, future stratigraphers willconcentrate on (i) the reconstruction of earthenvironments and processes (including evolution)through time, (ii) the eficient location and recoveryof useful earth resources, and (iii) the studyof those geological hazards that can be understoodwithin a stratigraphic context. The firstobjective - reconstructing environments throughtime - requires the use of a conceptual frameworksimilar to the one that we term the geologicaltime scale (GTS). The 21st century GTS willbe based on GSSP designations at the base of allgeological Periods and, ultimately, Ages, i.e. itwill comprise an internationally agreed chronologichierarchy. Recognition of local chronologicschemes (as distinct from biostratigraphiesbased on Oppelzones) will thereafterserve no useful purpose and local “Ages” willbecome redundant. Globally, recognition of aseparate but completely parallel chronostratigraphicclassification will also serve no usefulpurpose, and this hierarchy too will be abandoned.Correlation of events into the GTS willbe undertaken using a wide variety of methods,including numeric dating, fossil occurrence,physical and chemical properties, tephrochronologyand astrochronologic retrodictions. Biostratigraphy,though remaining a vital tool, especiallyfor Phanerozoic strata, will carry no necessarycorrelation primacy. Meeting the secondand third objectives - locating and recoveringearth resources, and studying hazards - requiresfirst and foremost the creation of detailed geologicalmaps and stratigraphic columns. Thelithostratigraphic hierarchy of Bed-Member-Formation- Group-Supergroup is an efficient andmostly objective classification whereby usefulmaps and columns are created. Because geologicalmapping is concerned with local stratigraphicdetail and complexity, it cannot, like chronology,be organized within a global nomenclature. Overdifferent large areas, different major, genetically-relatedpackages of sediments correspondto the formation, filling and sometimes destructionof sedimentary basins - as driven by regionaltectonic events, and as influenced by regionalclimatic and oceanographic histories. Atthe supra-Group or supra-Supergroup level, majorsediment assemblages of this type are separatedby regional unconformities, as recognizedby the creation of a category of UnconformityboundedUnits (UBU) in the 1994 2nd edition ofthe International Stratigraphic Guide. Whetheror not UBU are continued with as a formal unitof classification, the strong need will persist forthe type of regional, unconformity-boundedunits that have successively been termed Sequenceand Synthem, for use as the highest levelwithin the lithostratigraphic hierarchy.2008040502定 量 生 物 地 层 在 年 代 地 层 和 年 代 表 构 建 中 的应 用 = Applications of quantitative biostratigraphyin chronostratigraphy and time scale construction.( 英 文 ). Pálfy J. Stratigraphy, 2007,4(2/3): 195-199Quantitative biostratigraphy finds useful applicationsin chronostratigraphy and time scalecalibration. Fixing the Global Stratotype Sectionand Point (GSSP) is made more objective if correlationpotential of alternative boundary levelsis compared using the Unitary Association (UA)method. The base of the Ladinian (Middle Triassic)GSSP is a case in which not the regionallymost easily correlatable ammonoid datum wasselected. Radio-isotopic dates are often obtained150