Super-Volcanoes, Part 5: The Altiplano-Puna Volcanic Complex, South America

Part 1 - Yellowstone is here.

Parts 2 - 4 are presented in the immediately preceding days.

Super-Volcanoes, Part 4: Taupo, New Zealand

Part 1 - Yellowstone is here.

Part 2 - La Garita, Colorado is here.

Part 3 - Long Valley, California is here.

Super-Volcanoes, Part 3: Long Valley Caldera, California

Part 1 - Yellowstone is here.

Part 2 - La Garita, Colorado is here.

Volcanoes in Virginia!

Caffeine 101 | National Geographic

A brief diversion.

Super-Volcanoes, Part 2: La Garita, Colorado

Part 1: Yellowstone is presented here.

Merry Christmas

Just taking a brief break.

Warning!! Water level is going to rise.

This should give you an idea of what might be under those rapids.

Saguaro: Sentinel of the Desert (1989)

Saguaro National Park

Arizona State of Mind: West District of Saguaro National Park

I discovered years ago that the "West District" of Saguaro National Park has the more "photogenic" cacti, because in the "East District" is of a higher elevation and the cacti show more frost damage.

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.

Wind Erosion and Landforms in Arid Environments

Posted for the same reasons as yesterday.  I miss the Western United States and its diverse Geology and Ecology.  In particular, Arches National Park.  After camera failures in 1977 and 1979, I finally returned there in 2016.  

Even when traveling alone, if I wanted to see someone "next weekend" in a distant city, I had to keep to a schedule of sorts.  So, circumstances only allowed half a day at Arches, but I got some photos after waiting almost 40 years.

 Figure 1.  Delicate Arch

 Figure 2.  Double Arch.

Figure 3.  Windows Arch.

Figure 4.  South Window Arch.

How Does the Wind Shape the Landscape?

Living in the Chihuahuan Desert for 14 years and traveling through the other three North American Deserts (Mojave, Great Basin, and Sonoran) between 1973 and 2017 gave me a good insight into eolian processes.

The four North American Temperate Deserts, in the Western United States and Northern Mexico, are due to the Rain Shadow Effect and their being within the Mid-Latitude High-Pressure Zone.

What is the jet stream and how does it affect the weather?

Some of My New Mexico Volcano-Related Photos - Part 1

[To be linked to other New Mexico Volcanic posts.]

On this post are some of my photos from east of the Jemez Mountains, of the Bandelier Tuff overlying older Basalts near and at the Rio Grande (from 1978) and a more recent photo taken by friends on vacation.

Here are a couple of them (labeled for educational use):

 Figure 1.

Figure 2.

I regret not having any other volcanic photos in the vicinity of the Rio Grande River.  When I was last on I-25 south, headed from Albuquerque to El Paso, I was in a hurry to reach my destination before nightfall, as El Paso freeways west of downtown were a "clustermuck" due to construction in 2016.

Northward of the Jemez Mountains and the Valles Caldera, here a few photos of three of the Albuquerque Volcanoes in 2015 (Arizona Trip #2) as I was leaving town, westward on I-40.  It wasn't until I checked Google Earth that I realized the extent of the Albuquerque Volcanic Field and what I had missed.  The age estimates for the volcanic field range from 170,000 to 70,000 years ago.

Figure 3.

Sitting atop the fissure-erupted basalt flows (left to right) are JA Volcano, Black Volcano, and Vulcan Volcano. The basal fissure-erupted flows overlie river terrace deposits.

After returning to I-40 West, a few miles later I again left the Interstate at Rio Puerco (Exit 140) to photograph a dissected (by erosion) volcano south of the freeway, as well as a basalt bluff and exposed terrace deposits near the Rio Puerco (seen below).

Figure 4.

I have yet to discover a name for this dissected volcano (above), just east of the Rio Puerco and south of I-40.

Figure 5.

Known variously as "Cubero Volcano" or "Flower Mountain"(?) (above), this apparently-dissected volcano sits atop presumed Cretaceous sedimentary rocks at Exit 104.  This is a view of the southern escarpment facing the Rio San Jose Valley.

In the McCartys-Grants Holocene basalt flows, on the Northside of I-40, the best exposures are between MM 96 and approximately MM 89 (near McBride Road). 

Figure 6.  

In the foreground (above), is a wetland hosted within an apparently collapsed lava tube. 

Figure 7.  Vesicular Basalt texture. 

 Figure 8.

Between the basalt flows in the foreground and the flows capping the mesa in the background, are Mesozoic sedimentary rocks.

Figure 9. 

Figure 10.

The McCartys flows are at the extreme northern end of the Zuni-Bandera Volcanic Field.  The estimated ages range between 3,200 and 1,250 years old.

Figure 11.  "Tachylite"

Tachylite "texture" on the surface of a McCartys flow. Because of the lack of internal structure (as with obsidian), the glossy surface readily decays upon long-term exposure to water.  It is a sign of a very young lava flow.

South of the I-40 intersection with East Santa Fe Ave. (Exit 85) is the El Malpais National Monument, certainly a worthy photo stop.  It would be a pleasure to spend 2 or 3 days exploring the Zuni-Bandera Volcanic Field as well as the Mt. Taylor Volcanic Field.  Several days of "homework" beforehand would yield more satisfying results.

[Some of My New Mexico Volcano-Related Photos - Part 2 will include the Navajo Volcanic Field.]

References:

Arizona's Ancient Super Volcano

Sky Island - New Mexico's Jemez Mountains

While watching and listening, please observe the variations in vegetation.  Recall the Orographic Effect, which leads to more precipitation in the mountains.  (The Orographic Effect takes place in more humid climates too, but its effects are more noticeable in the episodic precipitation of arid and semi-arid, temperate settings.)

With increased precipitation due to the Orographic Effect in arid and semi-arid climates, isolated and semi-isolated mountain ranges serve as "Islands of Diversity", due to variations in rock-types, elevation, slope-angles, slope-orientations, and valley-orientations in relation to daily and seasonal sunlight and soil-moisture retention.  Slope-angle also affects soil genesis and retention (greater slope-angle = more erosion).  

This increased micro-climate diversity also includes the "Morning vs. Afternoon Effect" (my terminology) that I have observed in the Eagle Mountains, the Franklin Mountains, and the Organ Mountains.  As the east side of the mountains receives the "cool morning sunlight", there is less soil (and plant-transpiration) moisture-loss due to evaporation.  In contrast, the west side of the mountains gets the "full brunt" of the afternoon sun and the dry air.

In the Guadalupe Mountains of SE New Mexico and West Texas, the southeast-orientation of McKittrick Canyon with its perennial (or semi-perennial) stream offers evidence of the "Morning vs. Afternoon Effect".  Though not within a canyon, one could make the same observation in regard to the small creek draining Aguirre Springs (Figure 1), on the east side of the Organ Mountains in southern New Mexico.

Figure 1.  Small creek draining Aguirre Springs (illustrating the segregation-by-density of "heavy minerals").

In these mountain settings, especially with the N-S orientation of the linear ranges of the Basin and Range Province, the Orographic Effect and the Morning vs. Afternoon Effect override the regional "Rain Shadow Effect".

Additionally, in mountain ranges derived from composite or caldera-type volcanoes, the presence of unconsolidated or "unwelded ash" can offer conditions more favorable to plant growth.  The shattered volcanic glass (as shards or pumice fragments) are chemically-unstable and in the presence of soil moisture and natural acids, the degrading ash provides a supply of nutrients to local plants.

So when watching videos referencing "Sky Islands", please keep these things in mind, as to the "Why?" in regards to vegetation (and micro-climate) diversity. 

COLORES | Sleeping Monsters, Sacred Fires: Volcanos Of New Mexico | New ...

Here is a video on New Mexico Volcanoes, because I have spent a significant amount of time visiting numerous volcanic locales in the state.

Geologic History of the Jemez Volcanic Field

An enjoyable video about the two geologic features responsible for a good chunk of the vulcanism in New Mexico, the Jemez Lineament and the Rio Grande Rift.

Prior to the 1978 Summer field season, spent on the Eagle Mts., we four "Eagle Mts. rangers" and our professor made a quick visit to the Jemez Mountains.  Though I didn't get "enough" slides taken of the caldera crater, here are a few images of the Bandelier Tuff overlying older Rio Grande Rift-related basalts east of the caldera crater.

 Figure 1.

 Figure 2.

Further east of the above photos.

 Figure 3.

The following photo was taken by a couple of friends on vacation, a few years ago.

 Figure 4.

Figure 5.

References: