柴达木盆地察尔汗盐湖CH0310钻孔沉积物磁化率及其影响因素分析

通过对长为523 m的柴达木盆地察尔汗盐湖CH0310钻孔沉积物岩性、磁性特征、高频质量磁化率、低频质量磁化率、频率磁化率和总有机碳（TOC）的实验分析，结果表明:CH0310钻孔中磁铁矿是沉积物磁化率的主要贡献者；由于受气候和环境的影响与控制，以弱氧化环境为主CH0310钻孔中沉积物的磁化率与粗砂粒级含量成正相关与粘土级含量反相关关系；进一步对磁化率和TOC的相关性分析发现，在不同的沉积层磁化率和TOC的相关性表现出正负差异，这反映了磁化率对气候与环境的响应模式在CH0310钻孔不同层位并不完全相同，揭示出湖泊磁化率影响因素的复杂性和它作为气候代用指标的不确定性，因此认为对于地处高原干旱区沉积速率快、沉积层特别厚的湖泊来说，如果用单一的磁化率指标来反映或恢复古气候和古环境的变化需要特别慎重。

Analysis on the Magnetic Susceptibility and Its Influence Factors of the Lake Sediments in the CH0310 Core of Qarhan Paleolake,Qaidam Basin

By analyzing lithology, magnetic features, the high frequency and the low frequency quality magnetic susceptibility, frequency magnetic susceptibility and total organic matter (TOC) of the sediments of the 523m CH0310 core in Qarhan paleolake, Qaidam Basin, the conclusion shows that magnetite is the main contributor to the magnetic susceptibility in the CH0310 core. Due to the impact and control of the climate and environment, magnetic susceptibility is positively correlated with coarse sand content and negatively correlated with the clay content in sediments from the weak oxidation environment dominated CH0310 core. Based on the further analysis on the relevance of magnetic susceptibility and TOC, the results present that the relevance of magnetic susceptibility and TOC in the different sediment layers show the positive and negative differences, reflecting the different corresponding model of magnetic susceptibility to climate and environment in CH0310 different layers, revealing the complexity of the factors as well as the uncertainty of the lake magnetic susceptibility as a proxy indicator of climate. Therefore, for the lake which is located in the plateau and arid area and has the rapid sedimentation rate and thicker sediment layers, special care should be taken if using magnetic susceptibility as a single indicator to reflect and reconstruct the paleoclimatic and paleoenvironmental changes.