【作者】 李玉成； 黄宝玉；

【Author】 Li Yucheng (Department of Earth Sciences,Nanjing University,Nanjing 210093) Huang Baoyu (Nanjing Institute of Geology and Paleontology,Chinese Academy of Sciences,Nanjing 210008)

【机构】 南京大学地球科学系； 中科院南京地质古生物研究所；

【摘要】 较大的湖泊中的贝类生长线的氧同位素可能记录了季节性的温度变化。对拔氏丽蚌（楔丽蚌）Lamprotula（Cuneolamprotula）bazini（Heude）和环带丽蚌（丽蚌） Lamprotula（Lamprotula）zonata（Heude）的生长线进行氧同位素研究表明,前者有较强的适应环境变化的能力。δ¹⁸O 值记录的襄汾地区晚更新世约97±8（KaBP）时古温度为20～24℃至30～34℃,古降雨量多出现代200～267mm,河水排泄不畅,积水成湖。这些结果给人的启示是：全球变暖后,该地区气温可能有较大升幅；降雨量的增加有可能在排水不畅地区形成水灾,应注意防患于未然。更多还原

【Abstract】 This study on the palaeoclimatic and palaeoenvironmental information was carried out using car- bon and oxygen isotope profiles from the Late Pleistocene Lamprotula in the Linfen and Xiangfen ar- eas （which areabundant in lamellibranchs,especially fossil Lamprotula.） showed that: 1.The cessation of Lamprotuls （Cuneolamprotula） bazini （Heude） shell deposition in fall and summer was rich in ¹⁶O (δ¹⁶O value of-14.4‰) while that in winter and spring is rich in ¹⁸O (δ¹⁸O value of-12.2‰) and that this fluctuation of 2.2‰ might indicate a change in seasonal water temperature of up to 10℃. 2.The palaeoenviroment of fossil Lamprotula was similar to that of living Lamprotula in the lower reaches of the Changjiang River,so the most suitable water conditions for the Late Pleistocene Lamprotula was temperature of 25～29℃ and pH value of 7～8,from which it can be inferred that the seasonal temperature of water changed from 20～24℃ to 30～34℃. 3.The shell mean oxygen isotope values of Lamprotula （Cuneolamprotula） bazini （Heude） and Lamprotula （Lamprotula） zonata （Heude） are-12.9‰ and-12.6‰,respectively,and can be converted to water δ¹⁸O values by the linear equation δ¹⁸Op（smow）=1.07δ¹⁸Os—0.58,so the δ¹⁸O values of water where they lived was about-14.4～-14.1‰,which are approximately 4‰ lighter than the mean δ¹⁸O value of the present raifall （-10‰）,which means that the annual mean precipitation on Xiangfen Lake during Late Pleistocene was 200～267mm more than it is to- day.更多还原