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We have very interesting plant-life here and where I live is actually a ridge formed by a very ancient meteorite strike that shattered an old sea bed (2.3 billion years ago) and the life forms are adapted to this

I think that on the old seabed you can find a lot of interesting things. Traces of life on stones

This seabed existed long before there was life on earth :)
But there are boulders filled with river pebbles from these ancient estuaries

I love finding stones with imprints of marine life :-)