山西吉县沃曲桃园下三叠统刘家沟组红层的古地磁研究

本文对鄂尔多斯盆地东南缘一个背斜剖面的早三叠世红层样品进行了古地磁研究.对逐步热退磁矢量序列进行主成分分析以及各磁组分的解阻温度谱分析,估计了携磁矿物.分离出4种磁成分:镜铁矿携带的沉积或沉积后剩磁;赤铁矿携带的化学剩磁;等温剩磁和粘滞剩磁.特征剩磁（最高解阻温度T_u≥670℃）通过倒转检验、（递增）褶皱检验,平均方向为偏角D=-25°,倾角I=41°,相应的极位置为65°N、356°E.

PALEOMAGNETIC STUDY ON RED BEDS, LIUJIAOGOU FORMATION (TRL) FROM TAOYUAN, YAOQU, JIXIAN, SHANXI PROVINCE

We have investigated the characteristics of remanent magnetizations of lower Triassic red beds from an anticlinal section at the southeast edge of Ordos basin. The pilot specimens were subjected to step-wise thermal demagnetization up to 670℃. On the basis of multicomponent analysis with the standard package LINEFIND, we calculated the unblocking temperature spectrum of each magnetic compenent, and estimated the magnetic carriers. The study reveals that red beds in this section consist of four remanent components, i.e., the chemical, depositional or post-depositional, isothermal and viscous remanent magnetizations. The characteristic remanent magnetizations （ChRM） （the highest unblocking temperature T_u=670℃） pass the posifive reversal and （incremental） fold tests. Its sample mean direction, declination D=-25℃, inclination I= 41°, and the paleopole correspondingly is at 65°N 356°E.