Non-marine ostracodes, charophytes and palynomorphs are abundant in most Cretaceous lacustrine basins of Easl Asia. However, their ranges are not directly integrated with marine biota that defines the Cretaceous stage...Non-marine ostracodes, charophytes and palynomorphs are abundant in most Cretaceous lacustrine basins of Easl Asia. However, their ranges are not directly integrated with marine biota that defines the Cretaceous stages. Non-biotic events st, ch as magnetochrons and radiometric ages in these terrestrial deposits enable their correlation with marine strata. The SKI north and south compositcd cores in the Songliao Basin present a continuous section of Upper Cretaceous non-marine fossil and magneto- chron successions in superposed order. These chronostratigraphic events are integrated with marine events by an XIY graphic plot between the core data and a global database of Global Section and Stratotype Points （GSSP） and key reference sections. This plot projects stage boundaries in marine sections into the SKI section and interpolates numerical ages to the tirst and last occurrences of biota and to lithostratigraphic boundaries. This stratigraphic experiment tests and relines age calibrations based on both manual interpo- lation of depths to numerical ages and cyclostratigraphy. Ages derived by interpolation are similar and ages by cyclostratigraphy are older because stage boundaries are calibrated to a different age scale.展开更多
基金Financial support was provided by the National Basic Research Program of China(973 Program,NO.2012CB822002)the National Natural Science Foundation of China(Project No.41172037)+1 种基金China Geological Survey(Project NO. 1212011120145)State Administration of Foreign Experts Affairs,China
文摘Non-marine ostracodes, charophytes and palynomorphs are abundant in most Cretaceous lacustrine basins of Easl Asia. However, their ranges are not directly integrated with marine biota that defines the Cretaceous stages. Non-biotic events st, ch as magnetochrons and radiometric ages in these terrestrial deposits enable their correlation with marine strata. The SKI north and south compositcd cores in the Songliao Basin present a continuous section of Upper Cretaceous non-marine fossil and magneto- chron successions in superposed order. These chronostratigraphic events are integrated with marine events by an XIY graphic plot between the core data and a global database of Global Section and Stratotype Points （GSSP） and key reference sections. This plot projects stage boundaries in marine sections into the SKI section and interpolates numerical ages to the tirst and last occurrences of biota and to lithostratigraphic boundaries. This stratigraphic experiment tests and relines age calibrations based on both manual interpo- lation of depths to numerical ages and cyclostratigraphy. Ages derived by interpolation are similar and ages by cyclostratigraphy are older because stage boundaries are calibrated to a different age scale.
