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华北平原孢粉沉积相研究表明 ,洪积扇和三角洲平原区沉积的花粉较多 ,花粉沉积浓度多在 30 0 0粒 /g以上。冲积平原区沉积下来的花粉较少 ,花粉浓度多在 10 0 0粒 /g以下。冲积物的花粉浓度可以作为划分不同地貌单元的指标。不同的沉积相存在着不同的孢粉组合。主流相一般沉积的花粉粒很少或不含花粉 ,花粉植物类型也较少。漫滩、心滩沉积的花粉较多 ,花粉植物类型也较丰富。边滩沉积的花粉较少 ,花粉浓度也低。自然堤和泛滥相以含有较多的松、卷柏孢子和当地花粉植物为特征。这些特征可以作为识别沉积相的指标。
The pollen depositional facies in the North China Plain shows that there are more pollen deposited in the alluvial fan and the delta plain, and the pollen deposition concentration is more than 30 000 grains / g. Alluvial plains deposited less pollen, pollen concentration more than 10 0 grain / g or less. The pollen concentration of alluvial sediments can be used as an indicator of different geomorphic units. Different sedimentary facies exist different sporopollen assemblages. The majority of pollen grains deposited in the mainstream generally have little or no pollen and fewer types of pollen plants. Floodplain, heart and beach deposition of more pollen, pollen plant types are also more abundant. The edge of the beach deposited less pollen, pollen concentration is also low. Natural dykes and flooding are characterized by the presence of more pine, cypresses and native pollens. These features can be used as an indicator of sedimentary facies.