Edited July 24
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Pinacate Home

Pinacate is here because partial melting in the mantle generated small batches of basalt magma that rose sporadically through the crust to build volcanoes on the surface. More than 400 monogenetic volcanoes, each unique unto itself, are scattered across 2000 sq km of Sonoran Desert area and a million-odd years of Sonoran Desert time. The same process is occurring in dozens of similar volcanic fields across western North America.

Neogene volcanic fields Recognizable Volcanoes in the Southwest: Volcanoes and glacial moraines are among the few kinds of landforms that are constructed; most are made by erosion. Erosion quickly erases small volcanoes because they are made of insubstantial fragmental material. Geologic maps of western North America show vast areas of volcanic rock but few of the source volcanoes remain. Quaternary age volcanic fields like Pinacate and kindred are young enough that erosion has not had time to destroy their fragile volcanic landforms.

Launch this kml file to locate Pinacate among the similar Quaternary volcanic fields. If you don't have Google Earth on your computer, you can get it here. Zoom down on a few of these fields to see round cinder-cone volcanoes scattered across the landscape. These are all monogenetic volcanic fields in that almost all of the volcanoes are the product of single, short duration eruptions.



Google Earth is great for mapping but the NASA images of the region taken from space approach art, art that makes us look at things differently.

Pinacate in the West: This stunning space view of western North America on a nearly cloudless late afternoon includes Pinacate, the dark circle above the Gulf of California (lower right).



Pinacate is the accent mark on the Gulf of California. The Pacific cloud deck 500 m thick covers half of Baja California but two dark islands project above the clouds on the left; Isla Cedros, close to the coast and Isla Guadalupe, further at sea. Guadalupe is an oceanic island volcano having age and composition similar to Pinacate.

This image looks straight down the tectonic plate boundary between North America and the Pacific to where it bends left beyond the Salton Sea. Crust is being created at spreading centers in the Gulf.



NASA - The meeting of art and science. A little square of classic basin and range physiography sits between Pinacate and the Gila River (lower left). The cloud eddy downwind of Guadalupe could never be seen from the ground but the contrails in the LA basin (middle right)are a common sight.