A Geological Tour of Denver, Golden, and Colorado's Front Range

Pericles Press Home | Book | Contact Us/Ordering

A Theory | Seven Nations | Governments and Empires | Geological Past

Geologic Time Period

The Idaho Springs Batholith

Gneiss and granite along the Chimney Gulch Trail

Granite or granitic feldspar, on the left, fused to grey gneiss along the Chimney Gulch Trail west of Golden. The gneiss here displays small "dikes," bands which cut across the layering of the formation, and "sills," bands which were injected parallel to the layering of the surrounding rock.

Chimney Gulch Trail (Idaho Springs Batholith)