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Ice bamboo


New member
This cave is in a very cold place in northern China. How did these ice bamboos form?


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Well-known member
They're interesting formations - I've seen ice stals  in UK cave entrances when freezing air is drawn in from outside  but not in patterns like this. My best guess for the cause of the difference in thickness would either be changes in air temperature (drips falling onto the existing ice  don't get chance to spread out as much before freezing when the air is colder) or changes in the amount of water seeping into the cave roof (more water dripping in at times causes the wider sections to form). Anyone got a better theory to fit the observed result?


Active member
total guess just for fun, that the difference in thickness is due to rapid freezing (or it'd trickle down evenly in a more normal stalagmite shape) and has some cycle of faster slower water feeding it... day/night cycle? All speculative though. Really we just need to ask the yeti who lives in that cave, it'll know.


Well-known member
Air temperature and rate of drip. As they are fairly regularly spaced I wonder if this is the result of a cyclical draught.  We have some stal in Reservoir Hole in a passage that consists of stalagmites with a goblet or plate shaped top. They formed from drips originating high in the roof.  I suspect in that case there has been a change in drip rate or size at some stage probably related to change in the climate.


Active member
Does anyone know how long these take to grow and whether there's a significant seasonal variation in temperature? In other words, do these form during one winter and melt in summer or are they produced over several or even many years?


Well-known member
These were found in Lathkill Dale in Derbyshire a month ago, a few metres inside an adit - it had been cold in the preceding days but it certainly wasn't freezing then, and these were just starting to melt. They do have a slight bulge though - is it possible there's some 'sagging' of the ice during the daytime that then firms up again at night?


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Well-known member
Ice formations are created rapidly and closely resemble most of the features we can see in the very slowly formed calcite formations. E.g. we sometimes see the cobbled effect featured here under a cascade (Charmouth in Dorset for those interested)


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