摘要
The authors investigated lacustrine chemical sediments on terrace-I of DongCo-a salt lake in the interior of the northern Tibetan Plateau and firstly discovered borax and acomplete sedimentary section with five pure mirabilite beds. According to the sedimentarycharacteristics of rhythmic layering, palaeotemperatures for the formation of the cold-phasemineral-mirabilite-at the profiles and ^(14)C dating, the authors applied the theory and method ofcomparative salinology in the study of the history of the palaeoclimate and palaeoenvironment ofDong Co in the early and middle Holocene and drew the conclusion that the salt lake had experiencedthe following climatic evolution: the warm and moist stage (>8470 a HP and possibly to 10500 aHP)->cold and dry stage (8470-8170 a BP)->warm and moist stage (8170-7590 a BP)->stage of repeatedclimatic oscillations (7590-7400 a BP, alternation of three dry oscillations and three moistoscillations in a generally cold climatic background)->cold and dry stage (7400-6940 a BP)->warm andmoist stage (6940-6620 a BP)->cold and dry stage (6620-6410 a BP)->warm and moist stage (after 6410a HP).
The authors investigated lacustrine chemical sediments on terrace-I of DongCo-a salt lake in the interior of the northern Tibetan Plateau and firstly discovered borax and acomplete sedimentary section with five pure mirabilite beds. According to the sedimentarycharacteristics of rhythmic layering, palaeotemperatures for the formation of the cold-phasemineral-mirabilite-at the profiles and ^(14)C dating, the authors applied the theory and method ofcomparative salinology in the study of the history of the palaeoclimate and palaeoenvironment ofDong Co in the early and middle Holocene and drew the conclusion that the salt lake had experiencedthe following climatic evolution: the warm and moist stage (>8470 a HP and possibly to 10500 aHP)->cold and dry stage (8470-8170 a BP)->warm and moist stage (8170-7590 a BP)->stage of repeatedclimatic oscillations (7590-7400 a BP, alternation of three dry oscillations and three moistoscillations in a generally cold climatic background)->cold and dry stage (7400-6940 a BP)->warm andmoist stage (6940-6620 a BP)->cold and dry stage (6620-6410 a BP)->warm and moist stage (after 6410a HP).
基金
National Natural Science Foundation grant 49833010.
