Welcome to visit Geoscience!

Geoscience ›› 2018, Vol. 32 ›› Issue (01): 145-153.DOI: 10.19657/j.geoscience.1000-8527.2018.01.14

• Sedimentology • Previous Articles     Next Articles

Analysis on Gravel Fabric Characteristics of the Yellow River’s Terraces in Gonghe Basin and the Environmental Signification

HU Mengjun(), FENG Shuqin, LI Xiangfeng, PAN Ninghui   

  1. College of Geography and Environmental Science,Northwest Normal University, Lanzhou, Gansu 730070,China
  • Received:2017-04-13 Revised:2017-11-26 Online:2018-02-10 Published:2018-02-05

Abstract:

Based on the mathematical statistics of gravel fabric characteristics of the 12 terraces along Yellow River in the Gonghe Basin,the particle size, shape and orientation of each gravel layer were calculated, and the characteristics of gravel fabrics were analyzed to explore the environmental significance. The studies showed the following aspects: (1)the components of gravels were complex, mainly including sandstone and quartzite; (2)the flat sphere was the main shape of gravels, and the roundness of gravel layers was medium and the degree of weathering was low; (3)the intensities of the flowing water were listed in descending order as T8>T7>T5>T4>T10>T2>T9>T1>T3>T6>T11>T12 when the gravel layers were formed, and the gravel layers of T1, T3, T4, T7, T8 and T11 were caused by the stable river, and T2, T5, T6, T9, T10 and T12 were formed in alluvial water environments;(4)the direction of each gravel layer was consistent with that of field observation, and the directions of gravel sources and ancient water flows in T1, T2, T5, T6 and T10 were complex, while those of T3, T4, T7, T8, T9, T11 and T12 were simple. The environmental significance of this study is relatively simple, but it can be further used to reveal the characteristics of climatic environment and the condition of ground uplifted combined with chronological data of the terrace.

Key words: Gonghe Basin, Yellow River terrace, gravel bed, fabric analysis

CLC Number: