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done with glyphs on paper. In this report weconsider some aspects of the inevitable migrationof the Geological Time Scale (GTS) intodigitized formats. On one hand we envisage theorganization and design of a dynamically interactive,community-based consensus GTS on theinternet, in open public access for worldwide use.On the other hand, the complete dataset from thelast published time scale, the “GTS2004” (Gradstein,Oggand Smith 2004a) is already availablein digital form, and has been used to generatecustom visualizations in TimeScale Creator, amachine resident application. The migration ofthe GTS2004 dataset to the internet, as the basisfor a communityconsensus GTS, would greatlyfacilitate the improvement of the dataset throughuser interaction. It would also transformthe GeologicalTime Scale from a shelf reference, or acomputer program, to an integrated worldwideresource in geoscience research, education, andpublic programming.古 地 理 学 、 古 气 候 学2008040506自 3.0 Ga 以 来 冰 期 和 超 级 大 陆 的 循 环 : 冰 川作 用 的 构 造 边 界 条 件 = Glacio-epochs and thesupercontinent cycle after 3.0 Ga: Tectonicboundary conditions for glaciation. ( 英 文 ). EylesN. Palaeogeography Palaeoclimatology Palaeoecology,2008, 258(1-2): 89-129Tectonic influences on long-term climatechange are of considerable current interest anddebate. This paper reviews the relationship betweenmulti-million year periods of glaciation(glacio-epochs) over the last 3 Ga of Earth historyand phases of supercontinent breakup andassembly. A preferred but not exclusive relationshipis evident between glacio-epochs and theirmostly glacially influenced marine record, withrifting. The earliest known glaciation (mid Archean2.9 Ga) is recorded in the marine MozaanGroup of South Africa deposited along the passivemargin of the Kapvaal Craton then part ofthe early continent Ur. The Paleoproterozoicglacio-epoch, exemplified by the Huronian Supergroupof Ontario, Canada ( 2.4 Ga) and stratain northern Europe and the U.S., is associatedwith rifting of Kenorland. A long Paleo-Mesoproterozoic non-glacial interval (c. 2.3 Gato 750 Ma?) coincides with continental collisionsand high standing Himalayan-scale orogenicbelts marking the suturing of supercontinentsNena-Columbia and Rodinia. A near absenceof glacial deposits other than at 1.8 Ga,may reflect lack of preservation. The extensiveand prolonged Neoproterozoic glacio-epoch recordseither diachronous glaciations or discretepulses of cooling between 750 and 580 Ma, andis overwhelmingly recorded by substantialthicknesses (1 km+) of glacially influenced marinestrata stored in rift basins. These formed onthe mid to low latitude (< 30°) oceanic marginsof western (Panthalassa: Australia, China,Western North America) and eastern (Iapetus:Northwest Europe) margins of a disintegratingRodinia. The youngest glacially influenced depositsformed about 580 Ma along the compressionalCadomian Belt exterior to Rodinia(Gaskiers Formation) possibly correlative withthe classic passive margin Marinoan deposits ofSouth Australia.A short-lived (1 to 15 Ma?) Early Paleozoicice sheet about 440 Ma grew over highlands onthe polar North Africa margin of Gondwana possiblylikely triggered by uplift at high paleolatitudesas large terranes (e.g., Meguma, Avalonia)rifted away from North Africa. Incised valleys,coarse glacial fills and thick (1 km +) ‘postglacial’shales suggest a continuing tectonic influence.Devonian cooling across the Frasnian-Famennian boundary (c. 376 Ma) is recorded bylocal ice covers in Brazil and Bolivia and islinked to elevated topography and enhanced erosionof continental crust. The Late Paleozoicglacio-epoch ( 350 and 250 Ma) coincides with ahigh paleolatitude positioning of Gondwana andthe growth of high standing topography whenGondwana collided with Laurasia to createPangea. Breakup after 180 Ma moved landmassesinto higher northerly latitudes and wasthe backdrop to global cooling of the Cenozoicglacio-epoch that commenced after the Paleocene–EoceneThermal Maximum (< 55 Ma).Earliest Antarctic ice at 40 Ma most likely nucleatedon the high shoulders of the TransantarcticRift coeval with opening of Drake Passage,and coincides with the earliest ice rafting in theArctic Basin at 43 Ma, followed by anotherpulse at 34 Ma. Accelerated glacierization inboth hemispheres occurred at 14 Ma during themiddle Miocene Transition but Milankovitchforcedcontinental-scale ice sheets did not nucleatein the northern hemisphere until after 3.5 Maon uplifted borderlands along North Atlanticpassive margins.A preferred association of the deposits of Proterozoicand Phanerozoic glacio-epochs with riftbasins reflects either a causal link between riftrelateduplift and regional cooling, or simplyenhanced preservation of glacial sediments. Glacialdeposits are poorly preserved in areas ofcompressional tectonics.前 古 生 界2008040507俄 罗 斯 西 伯 利 亚 地 台 文 德 期 Vanavara 组 的沉 积 环 境 = Sedimentation settings of the VendianVanavara Formation, the Siberian platform.152