摘要
昆仑山垭口地区有５个在时代上可以衔接的天然剖面，即垭口剖面（包括惊仙谷组、羌塘组、平台组和望昆冰碛层）、纳赤台沟组剖面、三岔河组剖面以及小南川和热水剖面，分别分布在垭口盆地、纳赤台后沟、野牛沟口、青藏公路原５９道班和东大滩热水地区。通过野外考察和室内分析，本区经历了以下演变阶段：３．４～２．５ＭａＢ．Ｐ．为温暖环境；２．５～１．１ＭａＢ．Ｐ．气候凉湿，高原海拔在１５００ｍ以内；１．１～０．６ＭａＢ．Ｐ．的昆仑－黄河运动将本区抬升至４５００ｍ以上，其中０．７～０．６ＭａＢ．Ｐ．期间经历了本区最大一次冰期——望昆冰期；０．６～０．３ＭａＢ．Ｐ．期间为间冰期，本区接受沉积；０．３～０．２ＭａＢ．Ｐ．发生垭口冰期；２００～１１ｋａＢ．Ｐ．为末次间冰期与末次冰期；
The Kunlun Pass Area is located at the border area between the Qiangtang Plateau and Qaidam Basin.There are five sections at different locations,and the result of 14 C dating,paleomagnetic measuring and other methods indicate that the sections are linked each other in age.They are:Yakou section(including Kunlun Gravel Bed,before 3 4 Ma B.P.,Jingxiangu Formation,3 4～2 5Ma B.P.,Qiangtang Formation,2 5～1 1 Ma B.P.,Pingtai Formation,1 1～0 7Ma B.P.and Wangkun Till),Naij Tal section(Naij Tal Gou Formation,0 6～0 4 Ma B.P.),Sanchahe section(Sanchahe Formation,0 4～0 06 Ma B.P.),Xiaonanchuan section(60～1 ka B.P.)and Reshui section(18ka B.P. to present). Based on field survey and data analyses,the environmental change in this area since Quaternary is as follows:warm environment in 3 4～2 5 Ma;humid cool environment in 2 5～1 1 Ma,and the elevation of this area was no more than 1 500m at that time;Kunlun Yellow River Tectonic Movement occurred in 1 1～0 6 Ma and lifted this area to 4 500 m above sea level;the maximum glaciation in this area Wangkun Glaciation(last but two)occurred in 0 7～0 6 Ma and interglaciation in 0 6～0 3 Ma;Yakou Glaciation (last but one)occurred in 0 3～0 2 Ma;the climatic variability occurred in the last interglaciation,and the climate was humid cold in the early period of the last glaciation;and ancient men lived in this area in Holocene Megathermal.
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
1999年第1期53-62,共10页
Marine Geology & Quaternary Geology
基金
国家科委"八五"攀登计划资助
北京师范大学校级课题资助
