地质学家认为，这个具有流体化喷出物的陨石坑表明，在地表下几米深处有一层永久冻土层或水冰。

Geologists think that this fluidized ejecta crater indicates that a layer of permafrost, or water ice, lies just a few meters under the surface.

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答案可能是，现在火星上几乎所有的水都被锁在地表下的永久冻土层中，更多的水被包含在这个星球的极地冰帽中。

The answer may be that virtually all the water on Mars is now locked in the permafrost layer under the surface, with more contained in the planet's polar caps.

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海滩上，有一个不规则的正在融化的永久冻土层。

On the beach there is a jagged layer of thawing permafrost.

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