The other day, some friends and I were hiking through the woods and we came along a big pool of clayish looking mud. It looked to be dried, but my friend through a rock into it, and when the rock splashed, it created a flower looking splash which immediately dried and stuck. No matter how big the splash was, it froze. There was a construction site near by. Any idea what could have caused this?

sounds like slow drying cement as often pumped underground to fill any voids.

Sounds like spike is extracting the urine.

but it had the desired effect..big

not at all, there used to be a few sites like that next to a constuction site for condos when I lived in Canada, and it does exactly what he describes

 

although it doesn`t actualy DRY or FREEZE per se, it`s that fine a "Mud" that if you throw a stone in it, the "Splash" will stay there!

 

often the surface has a skin about 4 to 6 inches thick and is quite liquid under it (very pleasant to walk through bare foot also).

That sounds exactly right. Okay. Thanks.