火星水手谷滑坡体体积的计算方法研究

Study on Volume Calculation Method of Landslides in Valles Marineris

火星滑坡研究对地球上高速远程滑坡形成机制具有借鉴意义,其中火星滑坡体体积的计算是调查难点之一。基于NASA火星侦查轨道器背景摄影技术,借助谷歌地球软件,对火星水手谷中的12处典型滑坡进行了识别与分析。运用Alfred S.McEwen公式和方格网两种方法,计算了火星滑坡体的体积V,得出火星水手谷中12处典型滑坡体的体积平均在1 500km3,最高可达5 452.4km3。采用数理统计理论,发现滑坡体体积V与堆积区域面积D满足V=103.046 D1.036,滑坡体高度H与滑移距离L之比(等效摩擦系数)与滑坡体体积V满足H/L=-0.029lgV+0.459的关系。分析滑坡体滑移距离L的影响因素,得出滑坡体滑移距离L与滑坡体体积V和滑坡体高度H基本呈正相关。将火星滑坡体体积计算结果与地球上217处滑坡统计数据进行对比,发现火星滑坡具有体积大、滑移距离远、低等效摩擦系数等特点。

The study of the landslide in Mars helps to reveal the formation mechanism of terrestrial rock avalanche.Landslide volume calculation is one of the difficulties in research.Based on the technique of Context Camera （CTX） in Mars Reconnaissance Orbit （MRO）,this paper identifies 12 landslides in Valles Marineris by using the Google Earth software.The paper applies the Alfred S.McEwen method and the square grid method to calculating the volume of landslide bodies.The results show that the volume of landslide in Valles Marineris is 1 500 km3 on average,and the maximum volume is up to 5 452.4 km3. Adopting mathematical statistic theory,the paper obtains the relationship between landslide volume V and area Dthat V=103.046D1.036and the ratio of landslide height and run out length H/L （equivalent friction coefficient） verss landside volume,H/L=-0.029lgV＋0.459.The study analyzes influence factors of sliding distance L and finds out that the sliding distance L has a positive correlation with the landslide volume Vand the height of landslide H. Comparing the statistical data of the landslide in Valles Marineris with 217 terrestrial landslides,authors find that the Martian landslides have the characteristics of large landslide volume,remote slip distance and low equivalent friction coefficient.