One of the most beautiful landscapes on the planet, and certainly the most colorful, the Colorado Plateau is mainly a region of fairly flat-lying rock formations which have been gently but quickly (geologically-speaking!) uplifted over the last few million years. 
 
   Now with elevations ranging up to over 11,000 feet (3300 meters), it is a fantastically multihued terrain of and pinnacles, arches, and canyons cut deep into the remains of great deserts, river basins, and seashores where dinosaurs once roamed. 
 
   Within this area, a number of smaller, individual plateaus are to be found, sometimes separated from one another by valleys or rivers.  They have names like the Kaibab Plateau, the Coconino Plateau, or the Aquarius Plateau (in Utah).  Each of them has its own distinct character and rock formations, though they are all part of the same larger picture.
 
   In Arizona, the Colorado Plateau is that part of the state that lies north of the .  It displays a long record of Earth's geologic history.  Underlying the sedimentary rocks are very old and rocks -- some of the oldest such units in the lower 48 States -- at almost two billion years old.  These rocks come from a time prior to the formation of North America.  The world looked very different then, with continents very unlike the ones we have today. 
 
   Due to relentless movements within the of the Earth, below the crust, those old land masses broke apart, drifted in various directions, and eventually reunited into a large supercontinent that geologists now call Pangaea.  
 
   The lower sedimentary formations of the Plateau were laid down along the shores of ancient Pangaea.  Sandstone, shale, and indicate that the prehistoric ocean advanced over this part of the world. 
 
   Later formations show that the old continent then elevated, and dried out, and was covered by vast deserts, like today's Sahara Desert.  Those sands, now consolidated into the rocks that are seen towering above Sedona, for example, later on gave way to more advances by the sea. 

   Then, as the crust of western North America started to break apart, again because of way-deep disturbances, volcanic activity began, and punched through the sedimentary layers to form such features as San Francisco Peak, north of Flagstaff, as well as other numerous mountain ranges, like Utah's Henry Mountains and Abajo Mountains. 
 
   The relatively young, once quite fluid molten rock called , is to be found in many places on the Colorado Plateau.  It is seen in Oak Creek Canyon, north of Sedona, the high plateaus of southern Utah, and the wild-looking landscapes of northwestern New Mexico. 
 
   It is not known for certain why all these rocks were elevated so evenly and quickly, all across the Four Corners region.  It is as though a giant, underlying, shallow, saucer-shaped dish just broke loose from lower layers within the Earth, and then started to bob up, carrying with it all those scenic strata. 
 
   Pre-existing rivers and streams then rapidly (because they couldn't even adjust their orientations -- the uplift was too quick) cut down through the mostly-soft rock layers, carving them all into the myriad of canyons we see today. 
 
   The Colorado River cut the most spectacular of these gorges, but there are plenty of others, too.  The uplift continues today, and the area is rocked by an occasional earthquake due to that motion. 
  
   Oh, yes, and all those red rocks?  It's because they had a high iron content that oxidized back then, and what you see today is really rust -- lots of rust-colored rocks, and amazing beauty. 

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Volcanic spires,
near Kayenta, Arizona.  

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