Re: Granite porosity

The porosity of fractured granitic rock varies greatly, while that of unfractured rock generally falls between 1 and 3 percent.

There are two ways to locate data on fractured granitic rock porosity:
1. Literature - There are numerous publications that address porosity in fractured granitic bedrock.
a. California - R.C. Graham
b. Idaho - J.L. Clayton, W.F. Megahan
c. Blueridge/Piedment - Pavich, M.J.

2. If you know of a particular soil series that developed from granitic bedrock, you can search the Soil Survey Lab's database (link provided below).

Two important things to consider:
1. age of the rock
2. weathering environment (climate - dry or humid or ?)

Anyone else?