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    Hi,

    I know Sinkholes are caused by the Earth giving way to water and other forces and gravity pulling from the core, but why the heck are there so many of them recently?

    They are very creepy- especially the Blue hole of Belize. By the way, why has only the 'hole' part broken apart from the force of the water and not the surrounding areas?

    Do the bigger sinkholes ever end? Some of them keep growing for years!!! I know it's stupid to think but ones like Brezniki,Guatemala,Ohio football field,etc. keep growing and look to engulf entire cities! Do you think they could ever engulf more than that?
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    (Original post by ronki23)
    Hi,

    I know Sinkholes are caused by the Earth giving way to water and other forces and gravity pulling from the core, but why the heck are there so many of them recently?

    They are very creepy- especially the Blue hole of Belize. By the way, why has only the 'hole' part broken apart from the force of the water and not the surrounding areas?

    Do the bigger sinkholes ever end? Some of them keep growing for years!!! I know it's stupid to think but ones like Brezniki,Guatemala,Ohio football field,etc. keep growing and look to engulf entire cities! Do you think they could ever engulf more than that?
    I don't think there are any more than usual, the coverage by the media is much greater at the moment than usual though.
    I guess in theory, large areas could collapse under a sinkhole, but remember conditions have to be specific to allow this and in practice most places are stable enough, either built on solid geology or stable sediment. Could definitely form the basis of a film, if there isn't already one! For example in Brezniki, the sinkhole occured in an area where the land was not filled properly.

    In Belize, the Great Blue Hole was formed during ice ages (quaternary glaciations.) Sea levels were lower due to land ice and the 'hole' was eroded through chemical weathering from rain. The rock that eroded was limestone which reacts with slightly acidic rain. Then after the ice ages the sea level rose again and filled the caves in. The cave was eroded because it was less resistant than the rock around it.
    Hope this helps a lot, any more questions feel free to ask
    -Geology AS level student, who wants to study Geology at Uni-
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    (Original post by CareerVet)
    I don't think there are any more than usual, the coverage by the media is much greater at the moment than usual though.
    I guess in theory, large areas could collapse under a sinkhole, but remember conditions have to be specific to allow this and in practice most places are stable enough, either built on solid geology or stable sediment. Could definitely form the basis of a film, if there isn't already one! For example in Brezniki, the sinkhole occured in an area where the land was not filled properly.

    In Belize, the Great Blue Hole was formed during ice ages (quaternary glaciations.) Sea levels were lower due to land ice and the 'hole' was eroded through chemical weathering from rain. The rock that eroded was limestone which reacts with slightly acidic rain. Then after the ice ages the sea level rose again and filled the caves in. The cave was eroded because it was less resistant than the rock around it.
    Hope this helps a lot, any more questions feel free to ask
    -Geology AS level student, who wants to study Geology at Uni-
    Ah; but does that mean entire cities in Russia/Guatemala are on unstable land? Some of them keep growing; I assume only the unstable land is the bit falling

    As for Florida, aren't tourist attractions at risk? Sure would be dangerous if a rollercoaster was over one and the ground collapsed.
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    (Original post by ronki23)
    Ah; but does that mean entire cities in Russia/Guatemala are on unstable land? Some of them keep growing; I assume only the unstable land is the bit falling

    As for Florida, aren't tourist attractions at risk? Sure would be dangerous if a rollercoaster was over one and the ground collapsed.

    Sinkholes arise when acidic water seeps down into the rock below the ground and erodes the rock. As I said before, conditions have to be just right for them to form, just being on unstable land (e.g. lake sediment) doesn't mean a sinkhole will appear. A side note (if you're still interesting in my ramblings!) Half of Mexico City is built on lake sediment, which in 1985 Mexico City earthquake led to liquefaction. This was a major cause of damage to the area.
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    (Original post by Cool Cat)
    *shudder* what's in it's 'mouth' I'd feel sick brushing there or washing my hands if that wasn't cleaned out first
 
 
 
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