Chemical weathering is the erosion or disintegration of rocks, building materials, etc., caused by chemical reactions (chiefly with water and substances dissolved in it) rather than by mechanical processes. This proves the sitiuation of sand seeping into a rock ans slowly breaking it.
In ancient times, it was easier to travel by boat than over land. Few roads existed during this time. Also, because of the rivers, this area had arich supply of fish and waterfowl that could be used for food. The land in this area was flat and fertile, rich in nutrients.
