【摘要】 古湖岸线的识别是沉积学研究中一个悬而未决的难题.本文以遥感卫星图像为主要资料,结合地面露头踏勘和文献调研,对新生代以来乌伦古湖可能的湖岸线及其沉积物分布进行追踪辨别,探讨乌伦古湖的演变过程.通过研究,从卫星图像上发现3期比较明显的湖岸线影像.对卫星影像所对应的沉积物进行了实地考察和验证,确认这些沉积物为湖泊滨岸沉积.借助文献调研认为第一期湖岸线可能形成于渐新世时期,恢复的古乌伦古湖的面积1.73×10~4 km~2,为现今湖泊面积的18.67倍;第二期湖岸线可能形成于上新世时期,古乌伦古湖面积为6.65×10~3 km~2,为现今湖泊面积的7.18倍.陆相湖盆湖岸线摆动十分频繁,需要借助沉积学、古生物学、层序地层学和年代学手段定量重建湖岸线的变化过程,建立滨湖地区的沉积演化模式.更多还原

【Abstract】 Recognition of ancient lake shoreline is an unsolved problem in sedimentology. Based on remote sensing satellite images, combined with outcrop survey and literature research, this paper traces and identifies the modern and possible ancient shorelines and the shoreline deposits distribution of Ulungur Lake since Cenozoic, and explores the evolution process of Ulungur Lake by shoreline variation. Through the study, three obvious lake shoreline images were found from satellite images. The outcrops corresponding to satellite imagery were investigated and validated on the field, and the sediments were confirmed to be lakeshore sediments. According to literature research, the first lake shoreline may be formed in Oligocene. The area of the restored ancient Ulungur Lake were about 1.73×10~4 km~2, which is 18.67 times the area of the present lake. The second lake shoreline may be formed in Pliocene. The area of the ancient Ulungur Lake were about 6.65×10~3 km~2, which is 7.18 times the area of the present lake. The shoreline oscillation of continental lake basin is very frequent. It is necessary to quantitatively reconstruct the change process of lake shoreline by means of sedimentology, paleontology, sequence stratigraphy and chronology, and establish the sedimentary evolution model of lakeshore area.更多还原