太行山南部前寒武纪红层的岩石磁学特征及沉积环境探析

thick layer of Precambrian strata in the southern Taihang Mountains red deposition, was considered as littoral-shallow marine deposition, according to its widespread ripple marks, mud cracks and bedding and other features. However, this understanding is in contradiction with the formation of red sediment which forms in a well permeable oxidizing environment. To this end, we conducted detailed field investigation and sampling system of Precambrian red beds in Huixian, Henan province. Several regular magnetic parameters were measured including room temperature magnetism and high temperature magnetism, in addition, some typical samples have also been measured by X ray diffraction. The results showed that the main magnetic minerals of red sandstone and purplish red clay are fine-grained and hard magnetic hematite and the grayish yellow clay rock mainly contains paramagnetic minerals and small amount of magnetite. Overall, hematite content in Taihang Mountains is much higher than that in paleosol S5 which is the strongest level of oxidation. Therefore, the red beds in Taihang Mountains formed mainly in good condition of permeable surface oxidizing environment. It is also in the process of formation and development of mud cracks and ripples structure, indicating that the effect of water on the deposition process. But its hematite content is higher than the Quaternary paleosols, which indicates that the water effect of these structures is short.