Palaeoclimatic and Palaeoenvironmental Information Using Stable Isotope Profiles from the Late Pleistocene Lamprotula in Dingcun Area, Shanxi

Key words: 
• freshwater Moiiusca sheii /
• axygen isotope profiie /
• Late pieitsaene /
• paiaeociimatic information

Abstract: The paiaeociimatic and paiaeoenvironmentai information is studied by using the carbon and oxygen isotope profiies from the Late Pieistocene Lamprotula in Linfen and Xiangfe areas, where occur aboundant iameiiibranchs, especiaiiy fossii Lamprotula. The conciusions are as foiiows：1. The cessation of Lamprotula（Cuneolamprotula）bazini（Heude）sheii deposition in faii and summer is rich in¹⁶O, withδ ¹⁸O vaiue of - 14.5‰, whiie one in winter and spring is rich in¹⁸O, with δ ¹⁸O vaiue of - 12.2‰, and this fiuctuationof 2.2‰ may indicate a magnitute of change in seasonai temperature of water up to 10℃.2. The paiaeoenviroment of fossii Lamprotula was simiiar to ecoiogy of iiving Lamprotula in iower reaches of the Yangtze river, thus the most suitabie water for the Late Pieistocene Lamprotula was at temperature of 25 ~ 29℃ with a pH vaiue of 7 ~ 8. Therefore, the seasonai temperature of water changes from 20 ~ 24℃ to 30 ~ 34℃. 3. The sheii mean oxygen isotope vaiues of Lamprotula（Cuneolamprotula）bazini（Heude）and Lamprotula（ Lamprotula） zonata（Heude）are - 12.9‰ and - 12.6 ‰, respectiveiy. This sheiiδ¹⁸O vaiues can be converted to waterδ¹⁸O vaiues by the iinear eguationδ ¹⁸O_p（ SM0W）= 1.07δ ¹⁸O _s - 0.58, and, therefore, δ ¹⁸O vaiues of water where their iived is about - 14.4‰~ - 14.1‰. These vaiues are approximateiy 4‰ iighter than the meanδ ¹⁸O vaiue of the present rainfaii（ - 10‰）. It suggests that the annuai mean precipitation on Xiangfe Lake during the Late Pieistocene exceeded that of the pvesent by 200 ~ 267 mm.