2006-07-08 17:21:07 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Geography
Obviously, Harder Rocks & Mineral are more resistant to wind and water erosion than softer ones.
A perfect example is found in Badlands Areas...Hoodoos - the eerie-looking rock formations typical of these areas - are formed when Underlying Soft Sandstones begin eroding at a much faster rate than the Overlying Harder Iron-based layers...This results in Large Caps of Rock supported by ever-narrowing columns of Sandstone beneath them...until the structure eventually collapses.
2006-07-11 22:11:25 · answer #1 · answered by AlbertaGuy 5 · 0⤊ 0⤋
The more diverse the mineral makeup of a rock, the longer it takes to weather.
Example
A stone in a riverbed with no minerals will take a relatively short time *about 75-100 years* to weather down to a pebble.
A stone with a varied mineral makeup in a riverbed will take longer as the seperate minerals cause the stone to prolong its current size.
2006-07-08 17:25:56 · answer #2 · answered by hereticaldreams 2 · 0⤊ 0⤋