| Tangshan urban area located in the northern margin of geotectogene of North China Plain,there are a lot of faults crossing the city.In the all of them,Douhe fault and Guye fault divided the urban area into three Quaternary sedimentarysub-areas--Jinggezhuang fault depression,Tangshan uplift and Kaiping fault whichcontrol the development process of Quaternary of Tangshan urban area.Based upon the analysis of drilling lithology,sedimentary facies,sedimentary gyration,granularity,wave speed,dating data and sporopollen information in Tangshan urban area,combining with the forefather datum and archaeomagnetism,the division evidence of lithostratigraphy and chronostratigraphy is determined,the studies on the Q uaternary stratigraphic division and correlation are carried out.Quaternary lithostratigraphy in the study area in Tangshan urban area can be divided into 4 units named Guan formation,Yangliuqing formation,Ouzhuang formation and Holocene.It is indicated in the study that the Quaternary strata character in the three sub-areas.Sediments in the Jinggezhuang fault depression is major in fluvial and pluvial facies,sediments in the Tangshan uplift is major in fluvial and eluvial facies,sediments in the Kaiping fault depression is major in fluvial,ice-water and marine facies.The reason for the difference above is the scale and thickness of the hollow and the fault activity.According to the latest division scheme and criterion, based on TL dating data and mark of event stratigraphy, Quaternary in Tangshan urban area was used to be divided into 4 parts including Lower-Pleistocene(Qp~1), Mid-Pleistocene (Qp~2), Upper-Pleistocene (Qp~3) and Holocene(Qh). The Pleistocene/Pliocene boundary is fit lower to M/G resversal (2.48Ma B.P.); Qp~2/Qp~1 boundary locates at B/M resversal (0.78Ma B.P.); Qp~3/ Qp~2 boundary is 0.128 MaB.P., corresponding to the Blake event, and Qp /Qh boundary is 0.012 MaB.P., corresponding to the Gothenburg event.
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