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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。
From the aspects of lithology strata, sporopollen assemblage and stratum contrast, the author makes an in-depth study and discussion of the stratigraphic age and sedimentary environment of the red beds in the Xihe Basin, and traces its geological evolution. The spore-pollen assemblage first discovered in this area is the sparse shrub grassland dominated by Artemisia, the dominant species of pine, walnut and gramineae, among which the genus Juglans and Ulmus are typical Paleogene . Based on the comprehensive analysis of lithological characteristics and biological characteristics, it is considered that the “red earth” stratum in the Xihe Basin belongs to the Neogene Baoguladara Formation (N2b), and the stratigraphic sequence types show on the plane the sedimentation from the margin of the basin to the center Environmental changes from rivers, alluvial fans, delta to lake.