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磁化率是新生代乃至前新生代地层古环境研究的常规代用指标,被广泛用于风尘堆积、湖泊沉积物以及海洋沉积物中。沉积物磁化率值的准确测量对于古环境重建十分重要。在磁化率测量过程中单个样品质量对于磁化率测量值的影响,目前尚无报道。选取甘肃临洮晚第四纪黄土—古土壤样品,通过测量同一样品不同质量的磁化率,查看样品质量对磁化率值的影响。结果表明,1)样品质量对于磁化率值具有显著影响。样品质量小于6 g时,LT297和LT365样品的低频磁化率值(!lf)随着样品质量增加而变大,质量达到6 g之后!lf基本保持不变。2)样品的频率磁化率(!fd%)与质量之间关系复杂,没有一定的规律,样品质量小于6 g时与大于等于6 g时相比,!fd%变化幅度加大。3)建议测量磁化率的样品净重以不少于6 g为宜。
Magnetic susceptibility is a common proxy for paleo-environmental studies of the Cenozoic and even Cenozoic strata, and is widely used in aeolian dust deposits, lake sediments and marine sediments. Accurate measurements of sediment susceptibility values are important for paleoenvironment reconstructions. The influence of the single sample mass on the susceptibility measurement during the magnetic susceptibility measurement has not been reported yet. The late Quaternary loess-paleosol samples from Gansu Province were selected to investigate the effect of sample quality on susceptibility values by measuring the magnetic susceptibility of different samples of the same sample. The results show that 1) the sample quality has a significant effect on the susceptibility value. When the sample mass is less than 6 g, the low frequency susceptibility values (lf) of the LT297 and LT365 samples become larger as the mass of the sample increases. After the mass reaches 6 g, the lf remains almost unchanged. 2) the frequency of the sample magnetic susceptibility (! Fd%) and the relationship between the quality of the complex, there is no certain law, when the sample mass is less than 6 g when greater than or equal to 6 g, fd% increase. 3) It is recommended to measure the magnetic susceptibility of the sample net weight of not less than 6 g is appropriate.