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This geologic overview focuses primarily on the Colorado Rockies and the Colorado Plateau, but adjoining portions of Wyoming, Utah and the High Plains as far east as the Black Hills of South Dakota also have important and related stories to tell.

Throughout this article, I'll refer to Colorado and these adjoining areas as our region of interest, which closely coincides both with the area shown in the NASA photo at Bearings just below and also with the area affected by Laramide uplift.

Colorado's generous endowments of accessible mineral wealth and fertile farmland were not inevitable birthrights. This overview ventures a "to the best of our knowledge" summary of Colorado geologic evolution current as of late 2004.

Colorado's story still includes many gaps and controversies, often around events and structures shrouded in deep time, deep earth or both.

The wavy fabric indicates solid flow at mid-crustal temperatures of 400-500C.

To recast barely conceivable geologic time intervals in a more familiar format, they'll also appear from time to time as military hours in a single 24-hour day (and all-nighter) of creation beginning at the planet's formation and ending with the here and now.

Geologic understanding requires careful attention to time as well as three-dimensional space, so we'd better stop here first.

If you're unfamiliar with geologic time terminology and abbreviations, take that detour now.

Over 50 Ma, an entire mountain range like the Ancestral Rockies can rise up and vanish.

The pink feldspar bands in the severely deformed metamorphic rock at right (a mylonite from the Homestake Shear Zone in the northern Sawatch Range) show the kind of internal folding you'd expect from warm taffy, but this rock didn't actually melt.

Most of them cluster around the intersection of these two profound lineaments, both which almost certainly cut the full thickness of the lithosphere.

This telling elevation distribution reflects a powerful synergy between truly ancient plate processes driven by the cooling of the earth in the presence of gravity and ongoing mantle processes driven by Lord knows what.

Events in the Basin and Range and along the West Coast have also influenced Colorado's physical development, particularly from ~80 Ma on.