Lab Methods - Calculating the water required to carve the Rio Grande valley.
Length
Rio Grande: 3034 km
Pecos R.: 1183 km
Total: 4217 km
Width
5 km, 5 km, 2 km, 3 km, 2 km, 3 km, 2 km, 2 km, 1 km, 0.5 km, 0.5 km, 0.5 km
Average: 2.15 km
Depth
Let's say 200 m
How Much Water?
Volume = length x width x height
Volume of Rio Grande and tributary:
4217 km x 2.15 km x 0.2 km = 1813 km3
If we assume we needed 100 km3 of water to erode away each km3 of the land, then we get a total of 181,300 km3 of water.