云南西畴仙人洞动物化石铀系年代  

U-SERIES DATING ON FOSSIL TEETH FROM XIANREN CAVE IN XICHOU, YUNNAN PROVINCE

作　　者：张新锋[1] 吉学平 沈冠军[1] 

机构地区：[1]南京师范大学地理科学学院,南京210097 [2]云南省文物考古研究所,昆明650118

出　　处：《人类学学报》2004年第1期88-92,共5页Acta Anthropologica Sinica

基　　金：国家自然科学基金 (4 0 0 730 2 0 )

摘　　要：本文报道晚期智人地点云南西畴仙人洞动物牙化石的铀系测年结果。 4个样品的2 3 0 Th 2 3 4 U年龄范围为 4 7— 1 0 5ka ,测定了其中 2个样品的2 2 7Th 2 3 0 Th年龄 ,结果与2 3 0 Th 2 3 4 U法的一致。在没有进一步的地层和年代证据的情况下 ,将西畴人牙化石的年代暂定为 4 7— 1 0 5ka或许是合理的。但洞穴地点骨化石铀系年代总体偏年轻 ,上述年代范围很可能被低估。本文结果与我们已有研究的广西通天岩、前洞等地点一致 ,是晚期智人在我国出现比原认为的早得多的又一例证。Xianren Cave, located ca. 300 m southeast to the town of Xichou County, Yunnan Province, is one of the numerous modern Homo sapiens cave sites in southern China. From the deposits inside the cavern, 5 hominid teeth together with an abundance of mammalian fossils representing 32 species have been recovered. We have tried to date the flowstone layers covering the fossiliferous deposits, but failed to obtain meaningful results because of their mediocre quality and low uranium contents. Then 4 fossil teeth were selected from the museum collection. Judging by the adhered matrix deposits, 3 of them (XRD-1, 2, 3) should come from the Middle Layer, from which the hominid teeth were believed to come, while another one (XRD-4) may come from the Upper Layer. ()^(230)Th/()^(234)U dating was carried out on all the 4 samples, yielding results in the range of 47 Ka and 105 ka. Independent ()^(227)Th/(()^(230)Th) determinations on XRD-2 and 4 gave results consistent within errors with those from ()^(230)Th/()^(234)U. It seems thus plausible to attribute the hominid teeth in a range of 47—105 ka. However, compared with the well established U-series dating of speleothem calcites, the U-series dates on fossil materials tend to be much younger. So it is highly possible for the above dates to be underestimated. In any case, the present results are in line with those from other modern Homo sapiens sites we have previously studied, indicating that the appearance of modern humans in southern China may be an event as early as in West Asia and South Africa.

关 键 词：晚期智人 动物化石 铀系年代 西畴 仙人洞 

分 类 号：Q981[天文地球—古生物学与地层学] Q915.879[生物学—人类学]