青海湖全新世短尺度水体环境演变的初步研究

STUDY EVOLUTLON OF HOLOCENE LAKE-LEVEL ON<Ka TIME SCALE IN QINGHAI LAKE

青海湖是闻名世界的高原内陆咸水湖，在湖滨岸线附近发育的特殊岩石─青海湖湖滩岩是研究第四纪气候事件与古湖面变化的标志岩石．湖滩岩的主要成岩期为全新世，其成岩序列发现有５１４０、４７００～４４００、３８８０～３６００、２８２０～２７２０、２５３０～２４６０、１９７０～１９００、１５３０～１４５０ａ等七个阶段．湖滩岩的成岩周期约为６００ａ左右，是青海湖全新世环境演化最短的断代模式和最新的地层剖面，并由此划出了青海湖全新世小于千年尺度的气候变化周期年表．

The beachrocks o-ccur around the Shore of Qinghai Lake.it is the Qinghai-tibet plateau and chcracteris to fluid dynamics of lake.This discovery is very significcnt to the study of enviroment evolution of the plat6ou Quatemory,and amcient climate,and envirorment of Qinghai lake during Holocene.The rock-forming order of Holocene beachrocks ot Qinghai Lake is very deer and now we have discovered seven stages,which are 5140,4700-4400,3880-3600,2820-2720.2530-2460,1970-1900,1530-1450.The rock-forming preild,of beachrocks,which is about 600a,is the newest division model of Holocene enviroment evohtion ot Qinghai Lake.Beachrocks which is the mark of stubing the relitionship between post-giaial perion climate are variations of water surface is the result of early epidiageneesis The discovering of beachrock brought to lisht the law of climate evolution of post-giajal Period at Qinghai Lake Holocene is a main rock fomning sarge of beachrock The sarge t6stified that climate of Holocene in China has the obvious chcracter of cold and worm dry and moist fluctuation The evolution of climate which include a olt of the shore Period of rewormness and moisture tends to be the dry -old temperature.The fomning of beachrocks shows that the evolution interior lobe has steped in the stage of carbonate and beachrocks is a very important mark of the interior lake evohtion.