| PDF: | |
| Time: | 2006 |
| Journal: | Geological Bulletin of China |
| Volumn: | 25 |
| Issue: | 9-10 |
| Pages: | 1143-1151 |
| Type: | Other |
| Author: | Juntao Jia,Pujun Wang,Bin Zhang,Xiaoqiao Wan |
Abstract: | The Cretaceous stratigraphic sequence of the Binxian subbasin is redefined according to the stratigraphic sections,combined with previous research. It is composed in ascending order of the Lower Cretaceous Banzifang Formation, Ningyuancun Formation, Taoqihe Formation and Quantou Formation and the Upper Cretaceous Qingshankou Formation, Yaojia Formation and Nenjiang Formation. Based on the lithostratigraphy, biostratigraphy, geological events and isotopic ages, the authors correlate Cretaceous strata of the Binxian subbasin with those in the Songliao basin. Isotopic dating of volcanic rocks indicates that the Banzifang Formation is equivalent to the upper part of the Shahezi Formation and the lower part of the Yingcheng Formation, while the Ningyuancun Formation is equivalent to the middle and upper parts of the Yingcheng Formation. The Taoqihe Formation may correlate with the top part of the Yingcheng Formation, Denglouku Formation and lowermost part of the Quantou Formation according to lithological and fossil plant assemblage evidence. The red bed in the lower part of the abolished “Niaohe Formation” as the product of the regional climatic event is equivalent to the lower part of the lower part of the Quantou Formation. The ostracod assemblage in this formation, which is characterized by prosperity of Triangulicypris torsuosus and Triangulicypris torsuosus var. nota, is similar to that in the Qingshankou Formation, and the charophytes Atopochara trivolvis, Aclistochara songliaoensis and Obtusochara niaoheensis are found in the Quantou, Qing-shankou, Yaojia and Nenjiang formations; therefore the “Niaohe Formation” is divided into the Quantou, Qingshankou, Yaojia and Nenjiang formations. |