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柴达木盆地是我国西北地区最干旱的盆地之一,常年盛行强劲的西北风,尤其在冬春季更甚。柴达木盆地西部地区自新生代以来沉积了巨厚的河湖相沉积。自上新世晚期以来,随着气候的逐步干化和盆地内部构造变形的加剧,该地区风力侵蚀地貌开始出现。早更新世出现的古盐壳和古雅丹地貌说明当时侵蚀已经相当剧烈。晚更新世以来,气候的极端干旱化和冰期的出现,更加促进了风蚀地貌的发育,在强劲的低空风力的雕刻下,形成了盆地西部几万平方千米的“百万雅丹”地貌,十分壮观。柴达木盆地不同地区地层的厚度和风蚀速率都不同,最大分别可达3 000 m和1.1 mm/yr,如此巨量的物质搬运必然为下风向的地区(都兰、青海湖地区、西宁盆地、黄土高原)的粉尘堆积提供可观的物源物质。研究表明,柴达木盆地西部被侵蚀的古湖相地层是上述地区,尤其是黄土高原重要的物源物质。随着研究的深入,其盆地内侵蚀物质输送到黄土高原的机制,已得到学界越来越清晰的认识。
The Qaidam Basin is one of the driest basins in northwestern China and enjoys a strong northwest wind all the year round, especially in winter and spring. Since the Cenozoic, the western Qaidam Basin has deposited thick sediments of rivers and lakes. Since late Pleistocene, with the gradual drying of the climate and the intensification of structural deformation in the basin, the wind erosion landscape in this area began to emerge. The paleo-salt shells and the paleadan that appeared in the Early Pleistocene indicate that the erosion had been quite dramatic at the time. Since the late Pleistocene, the extreme aridification of the climate and the advent of the ice age have further promoted the development of wind erosion landscapes. With the strong low-altitude winds carving, the tens of thousands of square kilometers of “Yard” Landform, very spectacular. The thickness and wind erosion rates of the different parts of the Qaidam basin are different, with the maximum being up to 3 000 m and 1.1 mm / yr, respectively. Therefore, the huge amount of material transported must be in the downwind direction (Dulan, Qinghai Lake, Xining Basin , Loess Plateau) dust accumulation provides a considerable source material. The study shows that the ancient lake facies eroded in the western part of Qaidam basin is the most important source material in the Loess Plateau. With the deepening of research, the mechanism of transporting eroding substances to the Loess Plateau in the basin has gained more and more clear understanding in the academic field.