期刊
ANTARCTIC SCIENCE
卷 20, 期 6, 页码 565-579出版社
CAMBRIDGE UNIV PRESS
DOI: 10.1017/S0954102008001375
关键词
hyporheic zone; McMurdo Dry Valleys; microclimates; patterned ground; permafrost
资金
- Rhode Island Space
- NSF [ANT-0338291]
- NASA MFRP [NNX06AE32G]
Thermal contraction crack polygons modify the generation, transport, and storage of water in Wright Valley gullies. Water generation is contributed to by trapping of windblown snow in polygon troughs. Water transport is modified by changes to the ice-cement table and active layer topography caused by polygon trough formation. Water storage is modified by sediment grain-size distribution within polygons in gully distal hyporheic zones. Patterned ground morphological variation can serve as an indicator of fluvial modification, ranging from nearly unmodified composite-wedge polygons to polygons forming in association with gully channels. Thermal contraction crack polygons may also constrain the gully formation sequence, suggesting the continuous presence of permafrost beneath the Wright Valley gullies during the entire period of gully emplacement. This analysis provides a framework for understanding the relationships between polygons and gullies observed on Mars. If comparable stratigraphic relationships can be documented, the presence of an analogous impermeable ice-cemented layer beneath the gullies can be inferred, Suggesting an atmospheric source for Martian gully-carving fluids.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据