RVA is the ratio of 3D volume (V) of a watershed to its 2D planimetric area (A). It is found after you have calculated the volume of a basin (see Minimum Eroded Volume or Lake Basin Volume). The index is a means to compare groups of watersheds in different phases of development. RVA is useful in comparing the relative effects of uplift and denudation in a tectonically stable mountain range versus one actively uplifting. Report RVA values to 2 decimal places for each watershed.

Refs:
Frankel and Pazzaglia (2005)
Frankel (2002) MS thesis at Lehigh University
Granger et al. (1996) Journal of Geology 104
Kirchner et al. (2001) Geology 29
Schaller et al. (2004) Journal of Geology 112
? Small et al. (1997) Earth and Planetary Science Letters
von Blankenburg et al. (2004) Journal of Geophysical Research 109