I am studying for the test on Monday and am trying to distinguish the difference between a Stock and a Dike? They both appear the same in the illustration. Is it that a Stock goes completely to the surface where a Dike stays below ground? And Plutons look just like a Batholith. Is that a big difference in each, or just that a Pluton is smaller and then how would you distinguish a smaller Batholith between a large Pluton?

-- Tina Miller (sultice@aol.com), February 17, 2001

Answers

I think the difference is that while sills are parallel to the surrounding rock, the dikes are almost perpendicular---or just are cutting through the other rock.

-- Deb Richards (Kizmet727@yahoo.com), February 17, 2001.

Dikes cut through rock vertically as a way of transporting magma to the surface,they are only 1 to 100 meters across. stocks are a large intrusion in the rocks underneath, but not as large as batholiths. They do not extend to the surface directly. sills are like layers between rocks that lie parallel to the existing rock.

-- Sandra Feocco (DOMINICK F @ Prodigy.NET), February 18, 2001.