松辽盆地北部晚白垩世陆相沟鞭藻及疑源类特征与沉积环境研究

通过对松辽盆地北部晚白垩世青山口组和嫩江组一段、二段中沟鞭藻及疑源类化石形态、丰度、分异度、优势度和组合等古生态特征研究 ,以及对微量元素硼含量、相当硼含量、锶钡比和硼镓比等地球化学特性的分析 ,得出在盆地北部沟鞭藻及疑源类化石的古生态、微量元素的分布规律与盆地内沉积相带的展布三者之间具有较好的相关性 ,说明松辽盆地的沟鞭藻及疑源类的发育和分布是由自生环境决定的。同时 ,通过专门对所谓“海侵”通道上的微体古生物和微量元素特征进行综合分析 ,未发现任何能证明海侵通道存在的证据 ,从而认为此海侵通道并不存在。

The Late Cretaceous nonmarine dinoflagellates,acritarchs and sedimentary environment in the northern Songliao Basin

The Late Cretaceous nonmarine dinoflagellates and acritarchs from the Qingshankou Formation and lower Nenjiang Formation of the northern Songliao Basin are quite different from those contemporary marine ones. The fossil assemblages show a close relationship to the sedimentary facies. And the elementary geochemical data show a close relationship to the sedimentary facies as well. The elementary geochemical data can not be used to distinguish continental facies and marine facies, but rather to distinguish relative salinity of the deposits. On the basis of the study of the micropalaeonology and elementary geochemistry from the “passageway” of transgression, a negative answer about the existence of the “passageway” is proposed here.