Explanation:
A model is used to help scientists visualise things that they cannot actually see. It can be thought of as a thinking tool, to help form explanations. Models are useful simplifications to aid understanding. ... It can then be used to explain further phenomena and to make predictions of future behaviour.
Answer - Ground water erosion is a type of carbonic acidic water. That goes into the holes thru the soil and pretty much cracks thru rocks.
Formed by erosion created by seafloor spreading
RIVER DELTAS ARE formed by erosion created by seafloor spreading
NOT:
caused by the movement of tectonic plates areas of infertile, rocky soil