颖河上游全新世黄土—古土壤物质来源研究

淮河支流颖河上游嵩山东麓丘陵台地与河流阶地-典型全新世黄土-古土壤剖面磁化率、粒度成分和＞0.1 mm 粒级百分比含量分析结果显示,该地黄土磁化率明显偏低,粒度比黄土高原地区粗,表明该地黄土具有不同的粉尘源区,由不同风力系统形成.深入论证分析揭示出颖河上游黄土是近源风尘沉积物,粉尘主要来源于孟津以东黄河冲积、洪积扇的松散河流沉积物.黄河下游的频繁决口、改道、泛滥沉积为风沙活动提供了丰富的物源,形成风沙活动的动力是东北风.3100 a B.P.以后气候趋于干旱,黄河下游泛滥频率增加,风沙活动范围扩大,沙尘暴活动强烈.

Material Source of the Holocene Aeolian Loess-Paleosol in the Upper Reaches of the Yinghe River

A Holocene loess-paleosol profile is studied on the river terraces,hills and plateau of the east piedmont of the Songshan Mountain in the upper reaches of the Yinghe River as a tributary of the Huaihe River.Higher resolution proxy data of magnetic susceptibility,particle-size distribution and >0.1mm grain-size percentage were obtained from the profile.The results indicate that the magnetic susceptibility of loess-soil sequences in the upper reaches of the Yinghe River was obviously lower than that on the Lo...