Magnetic susceptibility results from Xinmin section in An-shun, Guizhou indicate that the Permian Dalong Formation is with low values(6.4 x 10-8 m3/kg in average) and that their values increase significantly across the P-T boundary and are high, about 1.3 ~ 10.7 m3/kg, in the Triassic Luolou Formation, which shows the same variation trend with that across other P-T boundary sections in South China. A good positive correlation with both terrestrial sporopollen abundance and TiO2 variations proves that terrestrial influx attributes most of the magnetic susceptibility at Xinmin section. 3 paleoclimatic stages in the source area were figured out based on the variations of magnetic suscep- tibility and geochemical climatic proxies: Stage I (bed 1 to the middle of bed 2) is characterized by a warm/humid climate with strong chemical weathering; while a hot/humid climate with stronger chemical weathering dominates stage I1 (top of bed 2 to the P-T boundary), the climate condition change rapidly between much milder climate and humid climate; after a short transitional period, the climate in stage m (above the P-T boundary) turns into a relatively hot/ dry climate with obvious much stronger physical weathering and weaker chemical weathering.%贵州安顺新民二叠系—三叠系界线剖面磁化率测试结果表明,该剖面二叠系磁化率整体偏低（平均6.4×10-8m3/kg）,界线之上磁化率快速增加并相对稳定在1.3×10-7m3/kg附近,与华南其他二叠系—三叠系剖面磁化率变化趋势相同;与陆源孢粉丰度、TiO2曲线的同步变化趋势表明,新民剖面磁化率主要来自陆源物质。结合磁化率、地球化学指标的变化特征,将源区P—T之交古气候划分为3个阶段：阶段Ⅰ（1-2层中部）为化学风化作用较强的温暖潮湿的气候条件;阶段Ⅱ（2层上部-P—T界线）整体处于较强化学风化作用条件下温热潮湿的气候环境,变化较为频繁,表现为温润/湿热交替;阶段Ⅲ（P—T界线之上）物理风化加强,化学风化明显减弱,经短暂＂过渡段＂,气候总体转变为干热的条件。
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