盐湖湖床上自行移动的石头

醉壶仙

　　Racetrack Playa is a dry lake bed located 3,608 feet above sea level in Death Valley National Park, California. The playa is named after the "racetracks" left by stones that mysteriously skid across its surface.
　　跑道干湖是坐落在加利福尼亚国家公园死亡之谷中的一个干涸的湖床，海拔3608米。之所以被命名为“跑道”，跟在湖床中的石头有关，这些石头从湖床表面划过，并留下一道道让人匪夷所思的滑行“轨迹”。
　　The Racetrack is primarily covered with hexagonal saucers of dry mud, left after a very short season when the lake bed is covered with a shallow layer of water after rains wash down from the surrounding mountains and into the playa. But marring this surface is the creepy evidence of stones that move on their own.
　　湖床表面覆盖着一层龟裂的干泥，这是由于每年有一段时间雨水从周围的山上流下来，在湖汇聚成浅浅的一层，湖水蒸发之后，就剩下了龟裂的湖泥。但是这些能自行移动的石头在此显得极不协调。
　　Sliding slowly without any intervention for distances as long as 1,500 feet, the sailing stones have never been filmed in motion, yet they're definitely on the move. The strange phenomenon only happens every few years, and the tracks are left for several years for visitors to ponder. One hypothesis is that winds -- which can howl at up to 90 mph -- push the stones across the slick mud left as the lake bed dries up after a downpour. A second similar hypothesis poses that after a thin sheet of rain falls over the playa and night temperatures drop to below freezing, a layer of ice forms across the surface of the lake bed and the stones slide across the ice with the wind.
　　如果没有任何干预，这些石头能慢慢地移动长达1500英尺的距离。虽然没有用仪器记录下来，但是这些石头绝对是在运动着。这个奇怪的现象每隔几年发生一次，留下一道道痕迹给游客们去思考。有人认为是风的作用——这里的风速最高可以达到90英里每小时，干涸的湖床在一场大雨之后湖底因为积水而变的很滑，就有可能产生这种结果。第二个类似的说法认为，如果下一场小雨，加上夜间零度以下的温度，湖床表面就有可能结冰，这样风吹着石头移动起来就比较合理了。
　　The only way to find out for sure would be to set up cameras and environmental sensor tools to understand just what makes these rocks move. Until then, they will remain a mind-blowing mystery!
　　找到真相唯一的方法就是在此处设立摄像机，进行环境监控。在真正找到答案之前，这些石头仍然让人百思不得其解。