Study On The Characteristics And Geological Significance Of Neocene Red Beds Of Chepaizi Area In The Northwest Edge Of Junggar Basin

The causes of continental red beds and deposition model have summed up after reading a wide range of documents about the continental red beds. According to the core, logging and seismic data and the stratigraphical characteristics of Shawan formation and taxihe formation had been divided and correlated in Chepaizi area, northwest edge of Junggar basin. The study area deposited extensive braided river delta, lake sedimentary systems widely.According to the outcrop areas information and core logging data summarized in the study area, red beds have divided into the primary red beds and the epigenetic oxidation red beds. They can be divided into the three categories:River reddish layer, Lake reddish layer and the red beds intersected with rivers and lakes. River reddish layer is divided into the braided delta front type and the braided delta plain type while lake reddish layer is divided into beach bar type and the type of lake silt; And the red layer deposition between rivers and lakes develop in braided delta and lake facies. N1S1 mainly grows the red layer deposition of braided river delta type. N1S2 develops braided delta front type, braided delta front and lake intersection type, type of lake mud, beach bar-type red layer deposition from the source area to the lake. With the recession of lake and an adequate supply source N1S3-N1t3 develop braided river delta plain, braided river delta plain and the lake intersection type, type of lake mud, Red beach bar-type layer deposition.Both the primary red beds and the epigenetic oxidation red beds are subject to some particular sedimentary environment in drought area. So analyzing the distribution of red beds and the red layer deposition model is good for understanding the sedimentary characteristics of the study area.