内蒙古西河盆地新近纪“红土”记录的沉积环境  

Sedimentary environment of Neogene laterite records in the Xihe basin, Inner Mongolia

作　　者：孙黎明[1] 杨用彪[1] 吴云霞[1] 方晓峰[1] 李路华[1] 李耀辰[1] 赵永峰[1] 田立富[1] 

机构地区：[1]石家庄经济学院工程学院,河北石家庄050031

出　　处：《中国地质》2008年第4期683-690,共8页Geology in China

基　　金：中国地质调查局地质大调查项目([2005]矿调1-10)资助

摘　　要：笔者从岩性地层、孢粉组合、地层对比等方面,对西河盆地红层的地层时代与沉积环境,进行深入的研究和探讨并追朔其地质演化历程。本区首次发现的孢粉组合是以草本植物蒿属为优势种,松、胡桃及禾本科为次优势种的疏林灌丛草原,其中胡桃属、榆属为典型的古—新近纪属种。根据岩性特征及生物特征综合分析研究,认为西河盆地"红土"地层属于新近系上新统宝格达拉组(N2b),地层层序类型在平面上体现出从盆地边缘到中心沉积环境由河流、冲积扇、三角洲到湖泊的变化规律。The stratigraphic age and sedimentary environment of the laterite bed in the Xihe basin have been studied in detail in the contexts of hthology, sporo-pollen assemblages and stratigraphic correlation and the geological evolution process during that time has been traced. The sporo-pollen assemblage in this area is the veld whose dominant elements are herbaceous Artemisia and subordinate elements are Pinus, Juglans and Graminae, of which Juglans and Ulmus are typical Paleogene-Neogene genera and species. Based on a comprehensive analysis of the hthologic and biological features, the authors think that the ＂laterite＂ bed in the Xihe basin belongs to the Phocene Baogedawula Formation （N2b）. In a phn view, the stratigraphic sequence type shows changes of the sedimentary environment from the river, alluvial fan and delta at the basin edge to the deep lake in the center of the basin.

关 键 词：西河盆地 新近纪红土 孢粉组合 沉积环境 

分 类 号：P588.241[天文地球—岩石学]