Geochemical characteristics of the Tertiary and Quaternary eolian deposits in eastern Gansu province: Implications for provenance and weathering intensity by QI Lin, QIAO Yansong, LIU Zongxiu, WANG Yan, PENG Shasha

“…An eolian deposit section named Shaozhai, which has been developed since the Tertiary in eastern Gansu province, was analyzed for major-trace elements and Sm-Nd isotopic compositions to explore the relationship for the provenance and weathering intensity between the Tertiary red clay and Quaternary loess. The magnetostratigraphy data indicates that the basal age of the typical eolian deposits is about 5.23 Ma B.P.. …”
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Cenozoic stratigraphic correlation and the lower limit of Quaternary in Guanzhong Basin by Yougui Song, Minwen Lan, Huifang Liu, Maosheng Zhang, Xiaofen Fu, Qiangqiang Ning

“…Evidence from lithology, magnetostratigraphy, biostratigraphy and climate change supporting the lower limit of Quaternary strata should be confined to the boundary of "Yellow Sanmen" and "Green Sanmen" in the traditional Sanmen Formation or the boundary of eolian loess and red clay sediments around M/G boundary, and the paleomagnetic age is 2.6 Ma.Based on palaeomagnetic data of drilling cores, outcrops and previous literature, we revise the Cenozoic chronostratigraphic chart in Guanzhong Basin and amend or reallocate the ages of different strata from Eocene to Holocene.We propose that Neogene and Quaternary deposits in the Guanzhong Basin can be generally classified into two sets of different genesis sediments e.g.eolian and fluvial-lacustrine sequences.The eolian deposits can be extended to the Miocene period, which is older than previous conventional knowledge, and this Miocene eolian red clay sequences can be named as Duangjiapo Formation.This study is helpful to understand the formation and evolution of the sedimentary environment, paleoclimatic change, basin resource exploitation and geological engineering construction in Guanzhong Basin.…”
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