阿尔金山东段山前砾石钙膜累积速率及其在估算断层活动年代方面的应用

干旱－半干旱地区冲洪积物顶面土壤中发育的砾石钙膜含有明显的年龄信息，其工及由统计计算得到的累积速率可用来估算所在冲洪积物或土壤的形成年代。

ACCUMULATION RATE OF PEBBLE CALCIC COATINGS AND THEIR APPLICATION IN DATING FAULTS IN THE PIEDMENT OF EASTERN SECTION OF ALTUN MOUNTAINS

In the soil of the northern piedmont zone of the eastern section of Altun Mountains,the thickness of calcium carbonate coating on pebbles evidently increases with the growing age of soil or proluvial fans.On five period proluvial fans dated from 181 000 years ago to 8 000 years ago in this zone, the thicknesses of pebble calcic coatings were systematically and carefully measured, and the mean accumulation rate of the calcic coating was calculated to be about 0.01 mm/ka. Using this rate value, formation ages of some offset ancient streams and offset proluvial fans distributed along the Altun fault were successfully calculated. The ages estimated agree almost with the results determined by using 14 C and other absolute dating methods.