A few weeks ago I posted a map showing shifting meander patterns for the lower Mississippi River. Here are a few more geologic maps that are artistic masterpieces. The first is the geologic map of Colorado, compiled in the 1970s by the US Geological Survey:
The colors indicate rocks of various ages and types, and the map comes with an extensive legend. The map is available for download as four .jpg files plus the legend from geology.about.com. Here is a closeup at full scale:
There are a number of state geological maps available for download from the internet; a few of widely ranging quality can be found here.
Geological maps are useful for exploration for oil, gas, and minerals; and for environmental and engineering purposes. Here is a map from what is known as the fold and thrust belt of central Montana, near Canyon Ferry Reservoir:
This map is available for download from the USGS.
Grace and Peace
P.S. I say these are beautiful; my wife says she prefers pictures of flowers.