摘要
内蒙古自治区呼伦贝尔盟地区海拉尔盆地查干诺尔凹陷扎赉诺尔群自下而上划分为4个孢粉组合。云杉粉Piceaepollenites sp.-单束松粉Abietineaepollenites sp.-三角粒面孢Granulatisporites sp.组合,分布于大磨拐河组一段;罗汉松粉Podocarpidites sp.-双束松粉Pinuspollenites sp.-无突肋纹孢Cicatricosisporites sp.组合,分布于大磨拐河组二段;无突肋纹孢Cicatricosisporites sp.-刺毛孢Pilosisporite sp.-水龙骨单缝孢Polypodiaceaesporites sp.组合,分布于伊敏组一段;有突肋纹孢Appendicisporites sp.-桫椤孢Cyathidites sp.-星粉Astropollis sp.组合,分布于伊敏组二、三段。上述孢粉组合研究证明,大磨拐河组地质时代为早白垩世凡兰吟期—欧特里夫期(Valanginian-Hauterivian),尽管没有出现最原始的被子植物花粉,但也不排除部分进入巴列姆期(Barremian)的可能,伊敏组的地质时代为早白垩世巴列姆期-阿普第期(Barremian-Aptian)。据此认为扎赉诺尔群地质时代为早白垩世凡兰吟期—阿普第期(Valanginian-Aptian)。
From bottom to top, the Jalai Nur Group in the Qagan Nur depression, Hailar Basin, Hulun Buir City, Inner Mongolia can be divided into 4 sporopollen assemblages. The Piceaepollenites sp.-Abietineaepollenites sp.-Granalatisporites sp. assemblage is distributed in the first member of the Damoguaihe Formation; Podocarpidites sp.-Pinuspollenites sp.-Cicatricosisporites sp. assemblage in second member of Damoguaihe Formation; Cicatricosisporites sp.-Pilosisporite sp.-Pol）podiaceaesporites sp. assemblage in the first member of the Yimin Formation; Appendicisporites sp.-Cyathidites sp.-Astropollis sp. in second and third members of Yimin Formation. The study of above sporopollen assemblages has demonstrated that the geologic age of Damoguaihe Formation belongs to Early Cretaceous Epoch Valanginian-Hauterivian age, in despite of no primal angiosperm pollens came into sight, the possibility of Barremian age cannot be excluded; while the age of Yimin Formation is Early Cretaceous Epoch Barremian- Aptian age. On these grounds, the geologic age of Jalai Nut Group is Early Cretaceous Epoch Valanginian-Aptian age.
出处
《中国煤炭地质》
2010年第1期6-14,共9页
Coal Geology of China
基金
国家自然科学基金(30670138)资助
关键词
海拉尔盆地
查干诺尔凹陷
扎赉诺尔群
孢粉组合
早白垩世
Hailar Basin
Qagan Nur depression
Jalai Nur Group
sporopollen assemblage
Early Cretaceous Epoch
