Some of My New Mexico Volcano-Related Photos - Part 2

For the closer-to-El Paso volcanic features.  As a reminder, my Master's Thesis was on what are now called "Lava Tube Shatter Rings", located near Aden Crater (in the eastern Potrillo Volcanic Field) in southern Doña Ana County, NM . 

Figure 1.  Index Map.

Figure 2.  Aden Crater.

Figure 3.

Figure 4.  Features associated with Aden Crater and Aden "Rift"

Figure 5.  Aden Rift as seen from the margin of Aden Crater.

 Figure 6.

Figure 7.

 Figure 8.  On the outside margin of Shatter Ring #1.

 Figure 9.  In the Aden Basalts, somewhat northeast of Aden Crater.

Lava Tube Shatter Ring #1 location in relation to Aden Crater shown in Figure 4 and Figure 5.

Figure 10.

Figure 11.  Just outside of Lava Tube Shatter Ring #1.

Figure 12.

Figure 13.  Hollow Lava Cone (see Figure 4 Index Map).

A Lava Cone is a miniature Shield Volcano.  there are numerous Lava Cones in the area, but when most of them finish erupting, they usually collapse in on themselves.  This one didn't.

About 10 miles SSE of Aden Crater (Figure 1 Index Map) is Kilbourne Hole, a Maar Volcano.  The black flows in the mid-background are the existing older Afton Basalt flows.  A Maar Volcano forms when a rising magma body contacts a shallow aquifer.  The resulting steam explosions formed the crater, presumably over the course of weeks or months.  

The Tuff Ring partially-surrounding the crater, in the next three images, was formed from ash produced by the Phreatic Explosions, i.e., from the explosion-pulverized basalt.

 Figure 14.

Figure 15.

Outside of Kilbourne Hole, the ground in places is littered with Mantle Xenoliths with Basalt Rinds. 

Figure 16.

 Figure 17.  The West Potrillo Mts. largely consists of cinder cones.   

Figure 18.  Mt. Riley and Mt. Cox (to the right) are older exposed Andesite intrusions, exposed by erosion.

In the same Basin and Range crystal block as the Franklin Mts. are the Organ Mountains (north of the Franklins).  The southern and central parts of the Organ Mts. are made up of volcanics and intrusions related to the Organ Cauldron (Caldera), which is part of the Tertiary "Great Ignimbrite Flareup".

 Figure 19.

 Figure 20.

The regional "Granddaddy of them all" is the Proterozoic Thunderbird Rhyolite in the central Franklin Mountains.

 Figure 21.

On an early-1977 field trip, we visited some volcanic features south and southwest of the main parts of the West Potrillo Mountains.  I am not sure if these came from the vicinity of Potrillo Maar or Riley Maar (Figure 1 Index Map). 

 Figure 22.  

 Figure 23.