摘要
运用主成分分离及线性区段等方法 ,使早白垩世样品明显分离出二组磁组分 .叠加剩磁为喜山期重磁化 ,特征剩磁明显偏离现代地磁场方向 ,经倾斜校正后 ,有很好的一致性并通过了倒转检验 ,给出塔里木地块库车坳陷早白垩世巴西盖组古地磁新数据 .综合已有的古地磁结果 ,获得了塔里木地块早白垩世平均剩磁方向及平均古地磁极 ,阐明了塔里木地块早白垩世磁倾角明显偏低这一现象 .分析导致磁倾角偏低的诸多因素 ,认为压实作用可能是导致磁倾角偏低的重要因素之一 .
The paleomagnetic results of Baxigai formation of early Cretaceous in Kuche depression,Tarim block are reported. Two magnetic components were clearly isolated by means of principal component analysis method and Linefind method.Overprint component is a remagnetization of Himalayan,which is close to the present magnetic direction.Characteristic magnetic remanence shows obviously offset present magnetic direction.After tilted correction,ChRM shows well consistent and passed reversal test.Early Cretaceous magnetic mean direction was obtained by summarizing most of published paleomagnetic data in this area. Inclination shallowing is noticed in the early Cretaceous stratum,which could not be explained by tectonics only if we consider the periphery plates.Some factors,such as quality of paleomagnetic data,sedimentary process,as well as long period non dipole field and so on are excluded. The compaction is believed to be the most important factor resulting in inclination shallowing.Much more work should be done to verify this hypothesis and this will provide evident for solving the problem in tectonics [
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
2001年第1期72-82,共11页
Chinese Journal of Geophysics
基金
国家自然科学基金项目 !(49974 0 1 6) .
