Notes on the map:
The Rocks of the Valley of the Sun


by Richard Allen.  All rights reserved.

   You may send as many E-postcards as you wish, but the images may not be reproduced in any other way or for any other purpose.
   You can also download and print a more geologically detailed version of "The Rocks of the Valley of the Sun" and its accompanying color-coded GeoHistory in PDF format (.7MB).  If you don't have Adobe Acrobat Reader (with which to view it), you can download it for FREE from the bottom of this page.
You may download, print, and use this map for personal use only, but it and the GeoHistory text may not be reproduced in any other way or for any other purpose, PLEASE.

   (2) -- The geology is presented more in the context of "episodes" rather than a total breakdown of rock formations.  In other words, we put more emphasis on types of formation and corresponding time periods than on a hierarchy of individual formations.  In our experience, this makes geologic history easier to grasp for the average person.

   (3) -- Images are always being added to increase the number of views.  Some images will be replaced as better ones become available.  Many of these pictures were taken in primitive fashion during hikes and other outings.

   (4) -- Please feel free to contact us if you have a question about the geology shown.  It is impossible to go into much detail on the web pages -- whole books could be written about some of the places shown!

   (5) -- Any comments or corrections are appreciated.

   (6) -- Links to "definitions" may seem repetitive from page to page.  But they are that way on purpose as many visitors will only look at a page or two, and they might have arrived at those by way of search engines, without having seen other explanatory material.

   (7) -- Browsers without scripting enabled (which are few, these days, unless you have purposely disabled it) will show the "definition" boxes as whole web pages, requiring use of the "back" button to return to the page which referred it.

   (8) -- The map omits city limits and other political boundaries.  They would clutter it up and make it hard to see anything.  And in the scope of things geological, they don't matter a whole hell of a lot.

   (9) -- More notes will appear when we think of them.

  (10) -- Besides our own field studies, geologic information for this map has been distilled from:
     Geologic Map of Maricopa County, by the Arizona Bureau
      of Mines
     Geologic Map of Arizona, by the Arizona Geological
     Geology of Arizona, by D. Nations & E. Stump
     Roadside Geology of Arizona, by H. Chronic
     numerous other sources.  If you have specific questions,
      please e-mail us at

  (11) -- We hope you find our unique map enjoyable and useful!

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