The Sedimentary Environment Analysis Since The Late Pleistocene In Xingtai City

The Xing Tai area is located at the west edge of the North China Plain, and at the intersection of the Tai Hang alluvial plains and alluvial fans. The overall thickness of the Quaternary of Xing Tai city would be thinner from East to West gradually. So far, the lithostratigraphy, chronostratigraphic, sedimentary environments and other studies in Xing Tai area are still poor. As a result, further researching in this area provided important information to restore the appearance of lithofacies paleogeography and determine the type of sedimentary basins.In this essay, through the analysis of the detailed description of Quaternary drilling in Xingtai City, according to the analysis of lithology, lithofacies data and palynological data, then combined with the previous research data, the Quaternary division of Xingtai area as the Middle Pleistocene Yangliuqing group, Guan group of the upper Pleistocene, Holocene, Pleistocene lower loss.This paper is based on XingTai XTK-01borehole and its grain size, pollen, and dating data and so on, we divided the stratum. On the basis of core observation, the96samples have been tested by MS-2000Laser Grain Size Analyzer. We have drawn the cumulative probability curve and modal curve and analyzed the sedimentary environment and its stratum compartmentalization comprehensively. And by using the combination of cumulative probability curve sequence classify the Qp. The analysis results show that the cumulative probability curve mainly can be divided into" Qp3-1, Qp3-2, Qp3-3, Qp3-4"4segments from bottom to top, Preliminary judge Qp3-1was experienced The lower part of the river for the more coarse-grained phase deposition, deposition of the upper part of the small fluvial flooding; Qp3-2and Qp3-3were normal meandering river deposition, that were consisted of coarse channel deposits from the lower and the upper finer floodplain,they formed a "dual structure" mode; Qp3-4was accumulation of a thick layer of gravel, And the roundness and sorting are poor, so this section initially judged as moraines or debris that caused by flooding, followed was normal fluvial.Combined with the division of pollen zone, according to the characteristics of different pollen types which can represent the different climate characteristics, the upper Pleistocene to the next and divided into3pollen zone, two of the all pollen zone and then were divided into two subzones. The sporopollen assemblages express the warm-dry to cold drying to mild semi to cool and moist-a mild dry climate type partial alternating type of climate change, sedimentary environment evolution and particle size reflects the basic similarity, and generally with the Baiyangdian transgression events and transgressive events corresponding to Cangzhou. Therefore, combining with the pollen and granularity, and provide scientific basis for the further study of ancient climate and environment in Xingtai area, which provide the standards for the establishment of Xingtai stratigraphic frame.In total, studies have shown that the combination of cumulative probability curve not only provide the better evidence for environmental analysis but also a reliable sedimentary stratum compartmentalization. Combined with the division of pollen, it is meaningful to divide and contrast the fine stratigraphy.