摘要
恩施笔架山高海拔第四系砾石层可见多个沉积旋回。通过对砾石层地理位置、沉积学特征、层序特征等研究,认为该砾石层为洪积成因,属洪积扇相扇根亚相,并发育支撑砾石。通过研究砾石沉积旋回对比该区域第四系以来的升降运动,探讨高角度砾石层的成因与第四系以来的掀斜运动的关系。
Enshi Bijiashan high altitude quaternary gravel layer shows multiple deposition cycles. Based on the study of the geographical location,sedimentology characteristics and sequence characteristics of the gravel layer,it is considered that the gravel layer is the cause of the proluvial,which belongs to the diluvial fan root subfacies and develops the characteristic support gravel. The relationship between the formation of the high-angle gravel layer and the uplift motion in the Quaternary system is discussed by comparing the gravel deposition cycle to the lift movement of the area since the Quaternary.
引文
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