摘要
由于所有的地层划分和对比的标志都是穿时的,建议在区域层型剖面中以“最佳物理参考点(golden spike)”作为地层划分和对比的规则,并以放射性测年资料和已经验证的古地磁转换面作为时间界面划分的标准,同时辅以尽可能多的其它对比标志。据此,本文建议采用Globorotalia truncatulinoides的初现位(FAD)或Olduvai极性亚时的底界(1.9Ma)作为更新世的下界;以极性时Brunhes/Matuyama的界限(0.73Ma)作为中更新世/早更新世的分界;以同位素第5期的开始(128ka)作为晚更新世的下界;全新世则以第九届INQUA所建议的10ka为其起始。中国的第四系以北方的泥河湾和周口店剖面、西北的黄土剖面,以及黄海的QC_2孔为基础,与邻区的俄国西伯利亚北部、日本的房总半岛和大阪、越南的湄公河平原、泰国中部平原、印尼爪哇的桑吉兰以及新西兰等地的第四纪剖面进行了对比。除了广泛采用的测年资料和古地磁资料而外,在对比中还采用了其它的对比标志为依据。例如生物群:有孔虫的G.truncatulinoides的初现位(FAD)不但在中国海域和沿岸剖面中广泛发现,在日本房总半岛、高锅和挂川,以及新西兰均有发现;哺乳动物中的剑齿象(Stegoden)和大角鹿(Megaloceros)(或其相似属)在东亚或东南亚广泛分布;人类化石方面,据测年资料。
FAD Globorotalia truncatulinoides or the lower boundary of Olduvai SubchronQ. 9 Ma), the reversal horizon of Brunhes/Matuyama (0. 73 Ma), the beginning of isotope stage 5(128 ka)and 10 ka B. P. are taken to be the lower boundaries of the Lower .Middle and Upper Pleistocene and
the Holocene respectively in s paper. Quaternary sequences are correlated among China and its adjacent areas including Northern Siberia of Russia, Boso and Osaka of Japan,Mekong Lower Plain of Vietnam, Central Plain of Thailand, Sangiran of Indonesia and Wanganui Terraces and West Land of New Zealand mainly based on the data of radio dating and mag-netostratigraphy and supported as many other indications or marker horizons as possible such as hominid fossils, biological fauna, climatic changes, marine transgressive beds, tektite, isotope stages and so on(Fig. 1).
Fig. 1 Location of the sections.
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出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
1993年第3期1-14,共14页
Marine Geology & Quaternary Geology
