广西东攀二叠—三叠系界线剖面磁学特征及古气候意义  

Rock-magnetic characteristics of the Permo-Triassic boundary section of Dongpan, southwestern Guangxi, South China: implications for paleoclimate

作　　者：陈建业[1,2] 冯庆来[1] 

机构地区：[1]中国地质大学教育部生物-环境地质重点实验室,武汉430074 [2]中国地震局地质研究所地震动力学国家重点实验室,北京100029

出　　处：《地球物理学进展》2011年第2期529-539,共11页Progress in Geophysics

基　　金：国家自然基金重点项目(40839903);科研院所基本业务专项(IGCEAl006)资助

摘　　要：对广西东攀深水相二叠三叠系(T/P)界线剖面进行了高密度的岩石磁学研究.磁化率、饱和等温剩磁、不同S比值、FeO、Fe_2O_3/FeO曲线和磁性矿物综合研究显示:T/P界线下至界线上岩石的载磁矿物发生由低矫顽力组分向高矫顽力组分的截然转变,该转变发生在界线下约12cm处,这可能指示T/P之交气候发生由温湿向干热的转化.不同剖面T/P界线附近的磁化率曲线可以进行区域性对比;界线之下普遍存在的磁化率高值段可能指示了特殊的古气候意义.High resolution rock-magnetic study has been applied to the Permo-Triassic（T/P） boundary section in Dongpan, southwestern Guangxi, southwest China. Susceptibility, SIRM, S ratios and FeO, Fe2O3/FeO curves comprehensively show an obvious transit of magnetic carriers beyond the boundary, from low coercivity below the boundary to high coercivity above the boundary, indicating a climatic change from warmth-humidity to desiccationtorridity. Susceptibility curves at the vicinity of T/P boundary from different sections are quite resemblant, the typical ＂magnetic plateau＂ well beneath the T/P boundary may have special climatic means.

关 键 词：二叠-三叠纪之交 磁化率 岩石磁学 古气候 广西 

分 类 号：P313[天文地球—固体地球物理学]