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对经历过实验室磁性细菌培养的Chiemsee湖的4块干湖泥样品进行了磁学参数、粒度和XRD测量,结果表明样品中的主要磁性矿物以磁铁矿为主,并含有少量的硫铁矿。培养深度1～2cm处的样品在磁化率、百分比频率磁化率、无磁滞剩磁、饱和磁化强度和矫顽力等磁学特征上表现出和其余样品差别较大,分析认为这种差异可能是由于该层位的样品受到较多的磁性细菌产生的磁小体影响所致。样品的低温饱和剩磁测量表明样品中除了单畴(SD)磁铁矿之外,还存在多畴(MD)磁铁矿颗粒,利用粒度频率分布曲线对沉积物的来源进行了分析,表明Chiemsee湖的沉积物可能主要是沉积在湖泊周围的一些风积物在地表水流作用下,与一些粗粒级沙粒一并进入湖泊所形成,样品中的粗粒多畴磁铁矿可能是这些沉积物所携带的,与后期的磁性细菌关系不大。因此,沉积物中的磁学信号除了磁性细菌产生的磁小体的贡献以外,其他物源沉积物的贡献显然也是不可忽略的重要因素。
Magnesite parameters, particle size and XRD measurements of 4 dry lakes samples of Lake Chiemsee after laboratory magnetic bacterial culture showed that the main magnetic minerals in the sample are mainly magnetite and contain a small amount of pyrite mine. The samples at the depths of 1 ~ 2cm showed significant differences from other samples in the magnetic properties such as magnetic susceptibility, percentage frequency magnetic susceptibility, non-hysteresis remanence, saturation magnetization and coercivity. It is believed that this difference may be Is due to the sample of this horizon being affected by the magnetosomes produced by more magnetic bacteria. The low temperature saturation magnetization measurement of samples shows that there are multi-domain (MD) magnetite particles in addition to single-domain (SD) magnetite and the source of sediment is analyzed by the particle size distribution curve. It shows that Chiemsee Lake sediments may mainly be deposited in the lake around some of the aeolian material in the surface water flow, along with some coarse grained sand into the lake formed, the sample of coarse multi-domain magnetite may be these deposits Things carried by the late magnetic bacteria have little to. Therefore, in addition to the contribution of magnetosomes produced by magnetic bacteria to the magnetic signals in sediments, the contribution of sediments from other provenances is obviously also an important factor that can not be neglected.