Analog Study of Aeolian Features in the Qaidam Basin: Implications to Martian Climate
1, Long Xiao1
,2, Zhiyong Xiao1, Jiannan Zhao1, Jun Huang1, Yanan Dang2
1Planetary Science Institute, China University of Geosciences, Wuhan, China, 2Space Science Institute, Macau University of Science and Technology, Macau, China
Mars is a neighbor of our Earth with extremely cold and arid environment. Multi-source remote sensing data and in suit investigation show that the mrtian surface is rich in landforms that have comparable geomorphologies with those on Earth. Dunes and yardangs are among the most widespread aeolian features on Mars. The different types of aeolian features are controlled by specific wind field. However, there is an absence of meteorological data on Mars, so we know little about the actual wind regime at local scale and their significance on atmosphere circulation at global scale. For this problem, the aeolian features could serve as a unique indicator for the interaction between the atmosphere and surface. Their orientations, morphology, and movement may be used to infer aspects of the wind environment in which they formed. Therefore, they have the potential to be applied as a proxy for formative climate conditions for both of Mars and the Earth.
In this study we introduce the Qaidam Basin, NE Tibetan Plateau, as a new and unique analogue site for studying aeolian features on Mars. The Qaidam Basin is the highest and one of the largest and driest deserts on Earth, featuring with extremely low precipitation, high evaporation, high UV radiation, various aeolian geomorphologies and playa sediments. In Qaidam Basin, dunes are morphologically classified as barchan dunes, barchan dune chains, linear dunes and star dunes, similar in shape and size with its counterparts on Mars. The yardangs within the basin cover an area of ~20,000 km2, make it the largest yardangs region in China. These yardangs are mostly located in the northwest part of the Qaidam Basin, and wind is the dominate force for their formation. These yardangs show different sizes and shapes, such as mesa, long-ridge, zigzag-like, remnant cone-like, ark-shape, capsized boat-shape, and whale back-like yardangs.
The study of aeolian features in the Qaidam Basin in this paper is based on our most recent field investigation, high resolution satellite images and interpretation of published data by other researchers. We focus on the classifications, morphology and topography of the aeolian features. Their formation will be discussed with numerical modeling. For comparable aeolian features on Mars, our study is based on interpretation of images and data from HiRISE, CTX and CRISM. HiRISE and CTX images will provide high resolution images to search for and characterize the aeolian features on mars. CRISM data will be used to identify the mineral compositions. We plan to map the yardangs, dunes and playas in typical areas (e.g., Hellas basins, North Polar area), mainly focus on their geomorphologies and compositions. Our target is to comparatively study their origins combined with models both on Mars and the Earth.