磁铁矿的磁学性质与条带构造

本文研究了磁铁矿的磁化强度、居里温度、磁化率和磁化率各向异性等磁学性质。认为原始沉积的铁质在经受相当于居里温度的变质作用改造时结晶为各向异性晶体,其长轴方向获得了最大磁化强度,并在外磁场的长期作用下相互吸引连接成条带构造。构造作用的叠加产生了各种变形组构。

MAGNETIC PROPERTIES OF MAGNETITE AND BANDED STRUCTURE OF METAMORPHOSED IRON ORE

It is discovered by the study of Metamorphic Iron Ore of Qianan, Hebei Province, the iron rich bands consists of chains linked by magnetites (like magnetic needles) . We take this as a clue, studying the characteristic of crystal form and the composition, the saturatition magnetisation, magnetic capacity and anisotropy, curie temperature of the magnetites. We analyse the magnetites for the orientation and the linking by tye magnetic domain theory, we believe that the banded structure of the iron material abtaining very high magnetic intensity and by the attraction each other under the effect terrestrial field concertrating on the direction of the magnetic field before metamorphic temperature of amphibolite facies (eguivolent to curie temperature)during the increasing temperature of the metamorphism. The reason for the banded structure only occuring in Precambrian banded iron formation is the reginal metamorphism at that time.