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对西昆仑北缘山前盆地新生代沉积特征的研究结果表明,沿西昆仑山前发育的各沉积序列的垂向特征相似:古新世—中新世早期为石膏层、含瓣腮化石的石灰岩和紫红色较细粒的碎屑岩沉积,指示了海相和海陆过渡相较平静的沉积环境;中新世晚期—上新世初期开始出现陆相磨拉石,指示了陆相非平静的沉积环境,砾石的直径由下至上呈增大趋势,可能反映了西昆仑山体不断隆升,其间相对稳定的层段可能是构造运动间歇期或平稳期的沉积,指示了脉动式的隆升模式;磨拉石底部砾石的成分以沉积岩为主,向上火成岩和变质岩砾石逐渐增多,表明剥蚀程度不断加深。根据磨拉石建造的特征,判断剥蚀量和剥蚀强度自西向东有减小和变弱的趋势,可能暗示了西昆仑山晚新生代隆升有自西向东由强变弱的过渡特征。该结论与本区构造地貌学的研究结果一致。
The results of Cenozoic sedimentary characteristics of the piedmont basin in the northern margin of the West Kunlun Mountains show that the vertical features of each sedimentary sequence developed along the western Kunlun Mountains are similar: the Paleocene-Early Miocene is a gypsum layer with cheek fossil Limestone and fuchsia finer grained clastic sediments indicate a quieter sedimentary environment in which marine and continental transitions occurred. Late Miocene-Early Miocene terrestrial mullair began to indicate continental non-calm deposition Environment and gravel with a tendency of increasing from the bottom to the top, which may reflect that the West Kunlun Mountains have been uplifted. The relatively stable intervals during this period may be sedimentary periods during the tectonic movement or stable period, indicating the pulsatile uplift pattern. The composition of the gravel at the bottom of the molasse is dominated by sedimentary rocks, and upward igneous and metamorphic gravels gradually increase, indicating that the degree of denudation is deepening. According to the characteristics of the molasse, the trend of decreasing and weakening of denudation and denudation from west to east may indicate that the transition of the late Cenozoic uplift of west Kunlun Mountains from strong to weak from west to east. This conclusion is consistent with the study of the tectonic geomorphology in this area.