Research On Cementation Ages And Ancient Environment Of Jiangbei Conglomerate In Chongqing Region

Conglomerate and sandstone of Jiangbei'epoch what is called Jiangbei conglomerate by Ha Anmu .and called Jiangbei' gravel layers by Li Chunyi .which is a kind allothigenic supergene cemented rock that widespreads in lower terrace of Quaternary sediment along the river in Sichuan basin and it's adjacent area, and consists of conglomerate and sandstone. According to the Geochemistry of conglomerate and sandstone and contrast with prehuman' research result. We research it's chemic element, carbon 14 and ESR-dating method and a series analyse such as chemistry formation , magnetic susceptibility , 5 ¹³C and δ ¹⁸O of it's cemented material.in order to study into its formative age. main chemistry formations and cemented environment change of Jiangbei Conglomerate.The reference of studying on Conglomerate has been provided in Chongqing city and other regions.The article includes six parts:First part is selected background of researched problem.Current situation. Significance .Means and content of studying. And Technique route of studying.Second part is an introduction of the character of geognosy : location. Sediment. Structure and shape and so on.The third part is a brief introuction of nature overview of the research area.mainly including geology. Physiognomy. Hydrology. Hydrology and the characer of section in Fuzhong of Beibei.The fourth part is emphases chapter of paper. Analyzing formation ages and environment change of Jiangbei conglomerate.Firstly cementation ages of Jiangbei conglomerate: Ages of jiangbei conglomerate profile in Fuzhong Beibei by ¹⁴C : X13 (13930+350a), X12-2 (20390±430a), X7 (22540±3440a), X2 (24340±820a) .The ages of formation in the bottom are earlier than that in the upper .The bottom of section are formed in the last stage of late Pleistocene, while the top are formed in early Holocene. Ages of quarts samples of Conglomerate of Xiaba in Beibei by ¹⁴C (10470 ± 360a, 13200±460a, 23310±450a) . Ages of quarts samples of Conglomerate of Youxi in Jiangjin (15129 + 400a, 15421±140a, 22240 + 660a, 24360 ±900a, 35000a) . Reasearch by ¹⁴C implication, Cementation initially took place about 35000a (crystal calcite). Cementation eventually occured about 10470 ±360a from today. On the basis of measurement by using TIMS-U by Luo lunde (1988). Ages of cementation samples of Conglomerate of Xiaba in Beibei were 9100±700 from today; On the basis of measurement by using ¹⁴C by Yang Dayuan . Ages of cementation samples of Conglomerate were 13400±400a on the right of the frist terrace in the outfall of Baota River at Yi Chang city. Synthesize to ages of Jiangbei conglomerate profile in...