| PDF: | |
| Time: | 1995 |
| Journal: | Acta Geologica Sinina |
| Volumn: | 69 |
| Issue: | 4 |
| Pages: | 372-381 |
| Type: | Other |
| Author: | Pujun Wang,Xiaodi Du,Jun Wang,Dongpo Wang |
Abstract: | Situated in the northeast part of China （latitudes 42°-49°N; longitudes 120°-128°E）, the Songliao Basin is a Cretaceous nearshore continental basin.The authors of this paper determined, for the first time, the isotopic ages of the Cretaceous Quantou Formation to Nenjiang Formation (K1q-K2n) of the basin with K-Ar and Rb-Sr methods using samples of mudstones, cabonate rocks and evaporites. The K-Ar ages of mudstones are 123.3±8.3Ma for the third member of the Quantou formation(K1q3), 111.9-89.0Ma for the Qingshankou Formation(K2qn) and 77.6-76.8 Ma for the fourth member of the Nenjiang Formation （K2n4）.The Rb-Sr isochrone age of carbonate rocks of the first and second member of the Nenjiang Formation (K2n1+2) is 81 Ma and that of evaporites of the third member of the Quantou formation (K1q3) is 122.2 Ma. |