Rock magnetism and magnetic anisotropy in folded sills and basaltic flows:A case study of volcanics from the Taimyr Peninsula, Northern Russia  

作　　者：ZHANG ShuWei J. Harald WALDERHAUG YANG YueJun 

机构地区：[1]College of Computer Engineering and Software, Taiyuan University of Technology, Taiyuan 030024, China [2]Department of Earth Sciences, University of Bergen, AIl~gaten 41,5007 Bergen, Norway [3]State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083, China [4]Department of Applied Physics, Taiyuan University of Technology, Taiyuan 030024, China

出　　处：《Chinese Science Bulletin》2008年第5期759-767,共9页

基　　金：Supported by the Norwegian Research Council as a grant to HJW, Norwegian State Education Loan Fund (Register No. 1921471), SWEDARP and EUROPROBE

摘　　要：Magnetic measurements were performed on apparently deformed igneous rocks of 23 sites from the southeastern part of the Taimyr Peninsula. Rock magnetism and reflected light microscopy analyses reveal that fine-grained titanomagnetites up to pure magnetites mainly carry the majority of magnetic fabrics in the sills, and that the slightly coarser Ti-poor or -medium titanomagnetites carry most mag-netic fabrics in the basaltic flows. Magnetic anisotropies were determined by applying anisotropy of low-field magnetic susceptibility (AMS) on 180 unheated samples and 128 samples that had been pre-viously heated to 600°C during a paleomagnetic study to detect heating effects on the anisotropy of magnetic susceptibility (AMS) properties of volcanic rocks. Laboratory heating significantly affects anisotropy variations of these igneous rocks corresponding to the mineralogical changes during the heat treatment.Magnetic measurements were performed on apparently deformed igneous rocks of 23 sites from the southeastern part of the Taimyr Peninsula. Rock magnetism and reflected light microscopy analyses reveal that fine-grained titsnomagnetites up to pure magnetites mainly carry the majority of magnetic fabrics in the sills, and that the slightly coarser Ti-poor or -medium titsnomagnetites carry most mag-netic fabrics in the basaltic flows. Magnetic anisotropies were determined by applying anisotropy of low-field magnetic susceptibility （AMS） on 180 unheated samples and 128 samples that had been pre-viously heated to 600℃ during a paleomagnetic study to detect heating effects on the anisotropy of magnetic susceptibility （AMS） properties of volcanic rocks. Laboratory heating significantly affects anisotropy variations of these igneous rocks corresponding to the mineralogical changes during the heat treatment.

关 键 词：岩石磁学 磁各向异性 玄武岩 折叠式岩床 俄罗斯 

分 类 号：P584[天文地球—岩石学]