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对塔里木盆地西北缘库孜贡苏剖面晚白垩世—早中新世沉积物进行了热退磁及岩石磁学研究,结果表明岩石热退磁及岩石磁学特征随沉积环境可分为三种类型:潮下、台地边缘浅滩相岩石主要磁性矿物为磁铁矿及少量针铁矿、磁赤铁矿,磁性矿物含量较少、颗粒较小(假单畴),其天然剩磁强度较小,一般小于1×10-2A/m,在250℃～500℃能获得稳定特征剩磁方向,特征剩磁由磁铁矿携带;潮间、潮上带岩石主要磁性矿物为磁铁矿,并含有少量磁赤铁矿、赤铁矿、针铁矿,磁性矿物颗粒为假单畴和多畴,天然剩磁强度一般在1×10-2～1 A/m之间,在250℃～580℃能获得稳定特征剩磁方向,特征剩磁由磁铁矿携带;河湖相岩石主要磁性矿物为磁铁矿、赤铁矿,并含有少量磁赤铁矿、针铁矿,磁性矿物含量较多、颗粒较小(假单畴),天然剩磁强度一般在1×10-1A/m以上,多数样品特征剩磁由赤铁矿携带,少数由磁铁矿与赤铁矿共同携带。岩石磁学研究对于在沉积环境复杂剖面进行古地磁研究具有重要的意义。
Late Cretaceous-Early Miocene sediments of the Kuzigongsu profile in the northwestern margin of the Tarim Basin were studied by thermal demagnetization and rock magnetism. The results show that the thermal demagnetization and lithology of rocks can be divided into three types according to sedimentary environment: At the tide, the main magnetic minerals in the shoal facies margin of the platform margin are magnetite and a small amount of goethite, maghemite, less magnetic minerals and smaller particles (pseudo monodomain), which have a lower natural remanence Less than 1 × 10-2A / m, stable magnetic remanence can be obtained at 250 ℃ ~ 500 ℃. The characteristic remanence is carried by magnetite. The main magnetic minerals in the intertidal zone and tide are composed of magnetite and a small amount Maghemite, hematite, goethite and magnetic minerals are pseudo-monodomain and multidomain. The natural remanence is generally between 1 × 10-2 and 1 A / m, and at 250 ℃ to 580 ℃ The remanent magnetization is carried by magnetite. The main magnetic minerals in the lacustrine facies are magnetite and hematite, and contain a small amount of maghemite, goethite and more magnetic minerals, The particles are small (pseudo-monodomain), the natural remanence is generally above 1 × 10-1A / m, and most of the sample features remanence is composed of hematite With a few common carried by magnetite and hematite. Rock magnetism research is of great significance for paleomagnetic research in complex sedimentary environment.