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法 国 蒙 塔 格 尼 努 尔 中 纬 度 混 合 地 台 寒 武 纪 - 奥陶 纪 过 渡 期 的 碳 化 学 地 层 = Carbonchemostratigraphy of the Cambrian-Ordoviciantransition in a midlatitude mixed platform, MontagneNoire, France. ( 英 文 ). Álvaro J J; BauluzB; Subías I; Pierre C; Vizcaïno D. GeologicalSociety of America Bulletin, 2008, 120(7-8):962-975The Cambrian Drumian Carbon Isotope Excursion(DICE) and the Steptoean Positive CarbonIsotope Excursion (SPICE) have been so farreported in subtropical platforms: the DICEevent is a large negative excursion in 13 C carb recordthat nearly coincides with the beginning ofthe Drumian (Cambrian Series 3), whereas theSPICE event is a large positive shift in 13 C carbidentified close to the base of the Paibian (FurongianSeries). The chemostratigraphic excursionshave been recognized in carbonatedominatedplatforms, and their application tomid- and high-latitude, siliciclastic-dominatedplatforms has been problematic. This paper offers,for the first time, a high-resolution stratigraphicanalysis of this time span in a temperatewaterplatform (Montagne Noire, France) thatrecorded episodes of carbonate productivity innearshore environments. Two sections were analyzedin detail: a complete Cambrian Series 3–Tremadocian succession, devoid of carbonateinterbeds and paleogeographically located in thedistal part of the platform (Pardailhan nappe),and a Furongian-Tremadocian succession, whichhas limestone interbeds and represents theproximal part of the platform (Minervois nappe).The lower part of the La Gardie Formation inthe Pardailhan nappe displays background 13 C orgvalues of –22 punctuated by a large negative,middle Languedocian (regional substage) shift,peaking at –24.5. This negative excursion issimilar to the DICE event reported close to thebase of the Drumian, although the latter is exclusivelybased on 13 C carb values. Stable isotopes of13 C carb and 13 C org from both sections also indicatea common chemostratigraphic shift at the onsetof the Furongian. In nearshore deposits of theMinervois nappe, the 13 C carb background valuesfor the interbedded limestone strata of the Vald'Homs Formation gradually increase from –3 to–1 and are punctuated by a sharp increase in13 C carb values to >3.0. By contrast, in basinalshales of the La Gardie Formation in the Pardailhannappe, the 13 C org background values decreasefrom –22 to –27.1. This trend is directly controlledby total organic carbon (TOC) contentsand is interpreted to have been initiated bychanges in the degree of biodegradation of organicmatter, sulfate reduction, and methanogenesisbefore or soon after burial. Despite thisoverprinting and the very low degree of metamorphismreached by the shales, the 13 C org backgroundtrend is also punctuated by a sharp positiveshift in 13 C org values to >4.0, similar to theSPICE event. In addition, the asymmetric shapeof the SPICE excursion in the Montagne Noireshows evidence for the HERB event, a late Furongiannegative carbon isotope excursion notyet accepted as a worldwide chemostratigraphicanomaly.The recognition of both chemostratigraphicshifts in mixed and clayey strata opens new possibilitiesof chemostratigraphic correlation inmid- and high-latitude platforms, where carbonatefactories did not widely develop, and strataonly contain endemic fauna. This implication hasa major consequence because the Global StratotypeSection and Point (GSSP) of the Drumianand Paibian stages occurs near the base of bothexcursions.2008040524石 炭 纪 - 二 叠 纪 奥 斯 陆 裂 谷 经 历 六 个 阶 段 和65My = The permo-Carboniferous Olso Riftthrough six stages and 65 million years. ( 英 文 ).Larsen B T; Olaussen S; Sundvoll B; HeeremansM. Episodes, 2008, 31(1): 52-58The Oslo Rift is the northernmost part of theRotliegendes basin system in Europe. The riftwas formed by lithospheric stretching north ofthe Tornquist fault system and is related tectonicallyand in time to the last phase of the Variscanorogeny. The main graben forming period inthe Oslo Region began in Late Carboniferous,culminating some 20-30 Ma later with extensivevolcanism and rifting, and later with uplift andemplacement of major batholiths. It. ended witha final termination of intrusions in the Early Triassic,some 65 Ma after the tectonic and magmaticonset.We divide the geological development of therift into six stages. Sediments, even with marineincursions occur exclusively during the forerunnerto rifting. The magmatic products in the OsloRift vary in composition and are unevenly distributedthrough the six stages along the lengthof the structure.2008040525西 欧 密 西 西 比 亚 系 岩 石 的 生 物 地 层 分 带 和 对比 : 一 些 晚 维 宪 期 / 谢 尔 普 霍 夫 期 实 例 研 究 =Biostratigraphic zonation and correlation of Mississippianrocks in Western Europe: some casestudies in the late Viséan/Serpukhovian. ( 英 文 ).Somerville I D. Geological Journal, 2008, 43(2-3): 209 - 240In the Mississippian in Western Europe, biostratigraphiczonation and correlation of sequenceshas been refined using a combination offaunal and floral groups. In deep-water basinsand on shelves advances have been made in recognizingevolutionary lineages of conodonts,158