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野外调查发现赣州盆地第四纪红黏土中含有少量棱角分明的石砾,呈断续条带状分布,坡积、洪积特征明显。对赣州三个第四纪红黏土剖面样品的粒度分析的结果表明,粗粉砂(10~50μm)平均含量分别为29.14%,30.80%,38.15%,风尘粒级组含量不突出均小于40%,黏粒和粉砂粒含量较高,反映后期风化作用较强。运用X衍射技术对黄金(HJ)剖面第四纪红黏土和下伏风化碎屑物、砂页岩样品分别进行测试发现,第四纪红黏土样与下伏风化碎屑物、砂页岩样图谱相差较远,矿物成分含量也不相同。此外,对黄金(HJ)第四纪红黏土剖面的孢粉分析发现,该剖面样品中发现了一些水生草本花粉和喜湿润环境的蕨类孢子。综上测试与分析,我们推测,赣州盆地第四纪红黏土系高处古土壤和古风化壳被流水冲刷而下在地势低洼处沉积而成,后来由于地壳抬升、河流下切,至今沿着河流分布在100~200m左右的坡岗丘陵上,后期经历了较强的风化作用。
Field investigation shows that the Quaternary red clay in Ganzhou basin contains a few angular stone blocks with an intermittent banded distribution with obvious slope plot and alluvial characteristics. The results of particle size analysis of three Quaternary red clay profiles in Ganzhou show that the average contents of coarse silt (10 ~ 50μm) are 29.14%, 30.80% and 38.15% , Clay and silt content is higher, reflecting the stronger weathered later. Using X-ray diffraction to test the Quaternary red clay, downweathered weathering debris and sand shale samples in the gold (HJ) section, it is found that the Quaternary red clay samples and the underlying weathering debris, sand shale samples Differences between the map far, mineral content is not the same. In addition, sporo-pollen analysis of Quaternary red clay profiles of gold (HJ) revealed that some aquatic herbaceous pollen and hippocampus spores were found in the profile samples. Based on the above tests and analysis, we speculate that the Quaternary red clay system in the Ganzhou basin was flooded by flowing water and was deposited in the low-lying terrain. Later, due to uplift of the crust and undercutting of the river, Distributed in about 100 ~ 200m slope hills, the latter experienced a strong weathering effect.