Forums | HES 健康与环境科学

09 October 2023, 11:21 AM

Speaker: Zeheng He

Date: 2023-10-11

Time: 13:30-14:00 pm

Room: ES354

Online link:

https://meeting.tencent.com/dm/cHLE02oBtSPP

Meeting ID: 664-4757-0489

Title: Effects of atmospheric environmental factors upon aeolian sand ripples

Abstract:

Aeolian ripples are common geomorphic features on Earth and elsewhere. Sand ripples are small waves on bedform. Normally, the height scale of ripples is 1s mm and the wavelength scale of ripple is 10s mm. The formation of sand ripples is a non-linear process, which reflects ancient climates and environment changes in terrain conditions and aeolian sand flow structures. The morphological parameters of ripples depend on grain-size character, wind duration, wind strength, and other atmospheric factors such as air pressure, temperature, and relative humidity. Previous investigations on sand ripple development are largely focused on the effects of wind and sand, while neglecting the role of atmospheric environmental variables. However, these variables can directly affect air density and the inter-particle force, and thus controls the process of ripple morphology and development. This study will adopt wind tunnel and field experimentations to quantify these effects. The results of this study can enhance the understanding of the non-linear chaotic physics and have strong implications in estimating ancient and remote sedimentological environments.