The Effects of Weathering by Water By Richard Horn With years of water running underground this cave was formed The power of water So how does this water get underground to create caves Sink-holes So why does the sink-hole form? Years of weathering causes rock to erode and creates caves Or the cave ceilings collapse and the hole occurs above ground So what is the purpose of the sink-hole To allow water to have a direct root to the underground water system Although is stream is small it is the stream that cut out the cave. Water has caused these rocks to break up