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There is a rock that I have been climbing ever since I was a kid to get a magnificent view of an escarpment. One of the things that was part of our rock tour among other things was a perfect human child foot impression on top of the rock. It looks like the rock was molten or wet and someone just stepped on it before it dried.

Is this even possible?

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    $\begingroup$ Welcome to Earth Science Stack Exchange! Interesting question. To help people answer the question, it would be good to know the exact location — someone can probably figure out the rock type and age from that. A photograph would really help too. $\endgroup$ – kwinkunks Nov 6 '15 at 17:45
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As @kwinkunks and @Gordon Stanger say, it's not possible to comment usefully on your particular observation without at least a picture and further information about the site. However, if you're asking “Is this even possible?” as a general question, the answer's yes, but under special circumstances. As an example, picture a scene in ancient East Africa: some individuals made their way across a layer of volcanic ash on the ground, leaving footprints in the process. Whether the ash was already wet or later rainfall fell on a dry ash layer (light enough not to destroy the evidence), the wet ash hardened and the footprints were buried under more ash fall - the “Laetoli” footprint tracks, discovered in Tanzania in the 1970s by Mary Leakey and her team, are remarkable evidence of bipedalism in our ancestors of ~3.7 million years ago.

References:

https://en.wikipedia.org/wiki/Laetoli

http://www.sciencedaily.com/releases/2011/07/110719194356.htm

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    $\begingroup$ It is actually a rock in East Africa facing a major escarpment. I saw online pictures of “Laetoli” and i can assure you that this rock has a deeper impression that looks more real. I will take good pictures on my next visit and document all the anomalies. My profession is not in geology, so excuse the ignorance. $\endgroup$ – Edwin Nov 11 '15 at 1:44
  • $\begingroup$ @Edwin - For your next trip, bring a ruler/tape measure to place alongside the depression to be photographed; look for other close-by depressions to be similarly photographed (and take photos of the surrounding area anyway) – ideally, one would want to see evidence of multiple depressions or a track of them, as a piece of evidence for possible footprint identification; find out as much as you can about the area's geology and history – only certain materials are soft enough to take an impression, e.g. clay, wet sediments, volcanic ash. Anything else, anyone? All the best for your field trip :) $\endgroup$ – Jimbo Nov 11 '15 at 8:22
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I agree with kwinkunks, one can't give a specific response without knowing the kind of rock, age of the rock, whether there are other depressions/imprints of comparable size in the adjacent rock, etc. In general, whilst there is a feint possibility of preservation of a human footprint in very young rocks, it is wildly improbable. Consider the surface area of exposed rocks on the Earth, and the trillions of impressions from differential weathering, a host of diagenetic processes, heterogeneous rock textures, etc. It would be very strange if, by chance alone, some of these depressions didn't resemble a child's footprint. But please try to give more details so can we can evaluate this inquiry. Incidentally, this brings to mind some creationist 'arguments' for human and dinosaur footprints in the same strata. They have all been investigated, and all shown to be spurious.

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  • $\begingroup$ "It would be very strange if, by chance alone, some of these depressions didn't resemble a child's footprint." +1 $\endgroup$ – Gimelist Nov 10 '15 at 2:43
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Foot impressions don't have to old. Just take a patch of ground made of clay or silt, pour some rain on it. Wait until dry and it's hard as a granite in some cases.

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  • $\begingroup$ A site found at Happisburgh (Norfolk, England) is nice example of how estuarine mud was able to harden sufficiently to preserve footprints made ~850,000 years ago, before getting buried under further material – however, they only lasted a couple of weeks after overlying sand was removed by wave action, exposing the surface for its discovery in 2013: en.wikipedia.org/wiki/Happisburgh_footprints britishmuseum.org/research/research_projects/… $\endgroup$ – Jimbo Nov 10 '15 at 7:53

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