Grand Canyon

Mineral Resources of some Arizona National Monuments

In view of President Trump’s program to reassess some National Monuments, the Arizona Geological Survey has released flyers regarding the mineral potential of four Arizona monuments: Ironwood Forest, Grand Canyon-Parashant, Sonoran Desert, and Vermilion Cliffs. You may read these short flyers here: http://repository.azgs.az.gov/uri_gin/azgs/dlio/1715

Ironwood Forest, about 35 miles northwest of Tucson, has an active copper mine and, according to local geologists, much more potential resources both east and west of the active mine. You can read about the history of the Silver Bell mine in a new paper by geologist David Briggs here: http://repository.azgs.az.gov/uri_gin/azgs/dlio/1714 Briggs notes: “Over the past 130 years, the Silver Bell mining district yielded approximately 2.27 billion pounds of copper, 6.6 million pounds of molybdenum, 3.7 million pounds of lead, 40.8 million pounds of zinc, 2,100 ounces of gold and 5.95 million ounces of silver.”

The Grand Canyon-Parashant area has produced copper, uranium, lead, zinc, gold, and Silver from breccia pipe deposits within what is now the monument. Breccia pipes are vertical pipe-like structures comprising broken rock (breccia). They are collapse features that originate in the cavernous Redwall Limestone and subsequently propagate upward through upper Paleozoic and lower Mesozoic rock formation. A recent review by the Arizona Geological Survey indicates that there could be thousands of yet unexplored breccia pipes within the monument. (See my article: Breccia pipes of northwestern Arizona and their economic significance)

The Sonoran Desert monument west of Phoenix has historically produced , gold, silver, copper, and manganese from small mines. The Aguila manganese mineral district in the Big Horn Mountains produced 42 million pounds of manganese.

The Vermilion Cliffs area in northwestern Arizona has had some small production of uranium, but the AZGS concludes “ there is little geologic evidence for economic minerals deposits in the monument.”

Two of the monuments, Ironwood Forest and Grand Canyon-Parashant, have had significant mineral production and more inferred resources. Local geologists suspect there are more copper resources east and west of the active mining area of the Silver Bell mine, but that ground is effectively off-limits because it lies within Ironwood Forest National Monument. The monument was imposed over valid pre-existing mining claims. This should be taken into account in assessing their status. The imposition of National Monument designation greatly inhibits or even prevents development of valuable mineral resources.

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New Release – AZGS Guides to Northern Arizona Geology

The Arizona Geological Survey has just released an electronic version of a classical work for free download: “Geology of Northern Arizona – with notes on archaeology and paleoclimatehttp://repository.azgs.az.gov/uri_gin/azgs/dlio/1647

This is a two-volume set originally published in 1974, contains about 800 pages. Here are the contents:

Volume 1
Geology of northern Arizona with notes on archaeology and paleoclimate, pt. 1, Regional studies p. 1-407

PRECAMBRIAN GEOLOGY

A preliminary report on the older Precambrian rocks in the upper Granite Gorge of the Grand Canyon

Preliminary report on the Unkar Group (Precambrian) in Grand Canyon, Arizona

The late Precambrian Chuar Group of the eastern Grand Canyon

Upper Precambrian igneous rocks of the Grand Canyon, Arizona

Rb-Sr age of the Cardenas Lavas, Grand Canyon, Arizona

Precambrian polar wandering from Unkar Group and Nankoweap Formation, eastern Grand Canyon, Arizona

PALEOZOIC GEOLOGY

Paleozoic rocks of Grand Canyon

The Toroweap Formation: A new look

MESOZOIC GEOLOGY

Mesozoic stratigraphy of northeastern Arizona

Mesozoic vertebrates of northern Arizona

CENOZOIC GEOLOGY, PALEOCLIMATE, AND ARCHAEOLOGY

K-Ar chronology for the San Francisco volcanic field and rate of erosion of the Little Colorado River

Cenozoic volcanism and tectonism of the southern Colorado Plateau
Southwest paleoclimate and continental correlations

A resume of the archaeology of northern Arizona

STRUCTURAL GEOLOGY

Synopsis of the Laramide and post-Laramide structural geology of the eastern Grand Canyon, Arizona

Structural evolution of northwest Arizona and its relation to adjacent Basin and Range province structures

The Bright Angel and Mesa Butte fault systems of northern Arizona

ECONOMIC GEOLOGY

Review of the development of oil and gas resources of northern Arizona

Volume 2:
Geology of northern Arizona with notes on archaeology and paleoclimate, pt. 2 Area studies and field guides

GRAND CANYON

River guide of Colorado River–Lee’s Ferry to Phantom Ranch

Kaibab trail guide to the southern part of Grand Canyon, northern Arizona

NORTH-CENTRAL ARIZONA

Geologic resume and field guide, north-central Arizona

Interference and gravity tectonics in the Gray Mountain area, Arizona

Geology of Shadow Mountain, Arizona

SAN FRANCISCO VOLCANIC FIELD

Geo1ogy of the eastern and northern parts of the San Francisco volcanic field, Arizona

Field guide to the geology of the San Francisco volcanic field, Arizona

Geology of the Elden Mountain area, Arizona

Xenoliths of the San Francisco volcanic field, northern Arizona

SAN FRANCISCO MOUNTAIN

The volcanic history of the San Francisco Mountain, northern Arizona

Glacial and pre-glacial deposits in the San Francisco Mountain area, northern Arizona

Field guide to the geology of the San Francisco Mountain, northern Arizona

Phreatomagmatic deposits of the Sugarloaf tephra, San Francisco Mountain, northern Arizona

Preliminary geochemical study of the lava flows of Humphrey’s Peak, San Francisco Mountain, northern Arizona

VERDE VALLEY–HACKBERRY MOUNTAIN AREA

Miocene-Pliocene volcanism in the Hackberry Mountain area and evolution of the Verde Valley, north-central Arizona

Paleontology, biostratigraphy, and paleoecology of the Verde Formation of Late Cenozoic age, north-central Arizona

Field guide for southeast Verde Valley–northern Hackberry Mountain area, north-central Arizona,

HOPI BUTTES–NAVAJO BUTTES AREA

The geology of Hopi Buttes, Arizona

The Buell Park kimberlite pipe, northeastern Arizona

Field guide for Hopi Buttes and Navajo Buttes area, Arizona
BLACK MESA AREA

Field guide for the Black Mesa–Little Colorado River area, northeastern Arizona

Ground water in the Navajo Sandstone in the Black Mesa area, Arizona

Paleoenvironmental and cultural changes in the Black Mesa region, northeastern Arizona

JEROME AREA

Economic geology and field guide for the Jerome district

Other new releases:

GEOLOGIC HAZARDS IN ARIZONA
AZGS FIELD GUIDES TO ARIZONA GEOLOGY

Breccia pipes of northwestern Arizona and their economic significance

Breccia pipes are vertical collapse structures, typically a few tens to hundreds of feet across and hundreds to thousands of feet in vertical extent. The pipes formed more than 200 million years ago within Paleozoic and Triassic rocks over a broad area of the Colorado Plateau around the Grand Canyon. The pipes formed as groundwater, flowing through the Redwall Limestone, dissolved material along fracture zones and created caves. Continued dissolution caused collapse of overlying rocks into the caves forming breccia pipes and sink holes.

Breccia pipe secton

BP hwy 89The Survey has identified “1300 pipes or suspected pipes” in the region. “Mineralized breccia pipes—pipe-like masses of broken rock—may contain high-grade uranium ore and variable amounts of copper, gold, silver, vanadium and other mineral ore. More than 71 mineralized breccia pipes have been discovered in the region, and as of 2010, nine of these pipes yielded more than 10,500 metric tons of uranium.” “It appears from this work that the number of suspected breccia pipes is one to two orders of magnitude greater than previously recognized. (The number may be even higher since many pipes do not yet have a surface expression.) The study raises the possibility that the higher concentration of breccia pipes is likely to extend across the entire region.” This means also that there is potential for much more uranium and other valuable minerals.

The Arizona Geological Survey has just completed and made available a new report “Partial database for breccia pipes and collapse features on the Colorado Plateau, northwestern Arizona” which you can download here. The cover of the report shows Highway 89 crossing a depression, the surface expression of a breccia pipe.

Breccia pipe map NW AZ

The breccia pipes exist because of the nature of the Redwall Limestone, a 350-million-year old formation that forms high red cliffs near the bottom of the Grand Canyon. The limestone is actually grey, but has been stained by iron and manganese oxides derived from overlying formations.

The Arizona Geological Survey has another publication on the history of the Redwall Limestone itself. You can download it here. That publication is non-technical, has many illustrations and is suitable for the layman or classroom.

Among the properties of the Redwall Limestone are:

• Diverse and long history over the last 350 million years.

• Magnificent cliffs and red walls.

• Composed of ~99.5% pure limestone, ~95% of which is biologically formed in the

presence of organisms.

• Forms very chemically-resistant cliffs, yet it is a very soft rock (slightly harder than a

finger nail).

• Has thousands of miles of interconnected caverns spread out over the Colorado Plateau.

• Has many caverns, some with ancient and modern speleothems.

• Is the source of carbonate for the growth of abundant travertine deposits.

• Provides precious minerals, trace metals and uranium in breccia pipes

• Is a major source of high-quality groundwater to numerous and voluminous springs in

the canyon and region, consumed by most visitors to the canyon.

• “Living in the Past” implies the past of the Redwall Limestone is living with us today

Although the area holds great potential for mineral resources which could be mined with minimal disturbance to the environment, radical greens and their Congressional fellow travelers are bent on banning mining in the area.

On January 9, 2012, the Obama administration announced a 20-year ban on new mining claims on public land near Grand Canyon National Park, thereby denying access to valuable minerals resources. Now there is a proposal to establish “Grand Canyon Watershed National Monument” which would cover 1.7 million additional acres (see green areas on the map here). If established, then all mineral potential of the area would be off limits. See details of current and pending areas made off-limits to mineral production here.

See also:

Uranium mining and its potential impact on Colorado River water

Uranium mining ban near Grand Canyon all politics, no science

AZ Geological Survey to release County geologic maps online

In 1959 and 1960, The Arizona Bureau of Mines – University of Arizona, predecessor to the Arizona Geological Survey published the Arizona County Geologic map series. Until now, these important maps were only available in printed form.

Over the next two weeks, The Arizona Geological Survey will release the maps online for free download. The map scale is 1:375,000 and the contour interval is 500 feet.

You can check their facebook page for release announcements:

https://www.facebook.com/AZ.Geological.Survey

So far AZGS has release maps for:

Apache and Navajo counties: http://repository.azgs.az.gov/uri_gin/azgs/dlio/1618

Coconino County: http://repository.azgs.az.gov/uri_gin/azgs/dlio/1620  A portion of this map is shown below.

These maps are valuable in that they give the big picture of County and State geology. For a list of all maps available for download, see: http://repository.azgs.az.gov/facets/results/maps

Coconino county geologic map

 

 

 

The Redwall Limestone of the Grand Canyon

 

Redwall 2

The 350-million year old Redwall Limestone is one of the most prominent features of the Grand Canyon. Its features:

• Diverse and long history over the last 350 million years.
• Magnificent cliffs and red walls.
• Composed of ~99.5% pure limestone, ~95% of which is biologically formed in the presence of organisms.
• Forms very chemically resistant cliffs, yet it is a very soft rock (slightly harder than a
finger nail).
• Has 1,000’s of miles of interconnected caverns spread out over the Colorado Plateau.
• Has many caverns, some with ancient and modern speleothems.
• Is the source of carbonate for the growth of abundant travertine deposits.
• Provides precious minerals, trace metals and uranium in breccia pipes
• Is a major source of high quality groundwater to numerous and voluminous springs in
the canyon and region, consumed by most visitors to the canyon.
• “Living in the Past” implies the past of the Redwall Limestone is living with us today.

Brian Gootee of the Arizona Geological Survey has designed a 27-slide history of the Redwall Limestone intended for guides and educators. It can be downloaded here:
http://repository.azgs.az.gov/uri_gin/azgs/dlio/1572

It has great graphics and an interesting story.

See also:

Origin of the Grand Canyon
Origin of the Lower Colorado River – a geological detective story

 

 

An experimental virtual tour through the Grand Canyon

The Arizona Geological Survey is experimenting with new ways of communicating geology and geologic stories to Arizonans and K-12 educators.

AZGS has produced its first-ever map story which follows geologist Steve Rauzi and a team of geoscientists as they raft through Grand Canyon.

“In a sequence of 29 captioned images, you’ll see Grand Canyon and some of its tributary canyons as a geologist sees them. Rauzi fingers individual rock units and puts a face – of sorts – to the names of famous rock formations: Devil’s Ramp and Vulcan’s Forge – products of the Pleistocene Uinkaret volcanic field, Kiabab Limestone, Coconino, Tapeats and Muav Sandstone, Bright Angel and Hermit Shale, the Redwall, Temple Butte, and Bass Limestone, and the Vishnu Schist.

Steve and his companions ramble across ancient stromatolite beds – some of Earth’s earliest life forms, bushwhack across faults and massive rockfall deposits, and close in on the Vishnu Schist (river-mile 78), Arizona’s oldest rock formation, at the bottom of Grand Canyon’s inner gorge. At river mile 98, you’ll see a dory run Crystal Rapid, and at river mile 179 scout Lava Falls Rapids from a beach safely upstream.”

You can begin the journey here: A Geologist in Grand Canyon – Map Story. The graphic below shows the main page and the third image. Mousing over the inset on the right allows you to expand the image. Clicking the “x” on the bottom right of the expanded image returns you to the main page.

AZGS-front-screen

Here is the third image expanded. The caption reads “Peering upriver of Vasey’s Paradise. Springs flow from the Mississippian Redwall Limestone. The overlying cliffs are formed of Permian Supai Group, Hermit Shale, Coconino Sandstone, Toroweap Formation, and Kaibab Limestone.” The boats provide a sense of scale.

AZGS-Grand-canyon-mile-32

AZGS is soliciting comments from the public on improving the model. Comments may be sent to Mike Conway (Michael.conway@azgs.az.gov | 520.209.4146)

I learned something from this tour. I didn’t know that the Grand Canyon contains stromatolite beds (image 5) which are fossils of the earliest known life form on Earth.

Check it out. You may learn some geology and, if nothing else, there is some great scenery.

Origin of the Lower Colorado River – a geological detective story

The origin of the Lower Colorado River has been a controversial topic within the geological community.  The latest hypothesis was put forth by Philip Pearthree of the Arizona Geological Survey, Kyle House (now with USGS), and Michael Perkins (Univ. of Utah).  Their paper, “Stratigraphic evidence for the role of lake spillover in the inception of the lower Colorado River in southern Nevada and western Arizona,” Geological Society of America Special Paper 439, has just been awarded GSA’s prestigious Kirk Bryan Award for Research Excellence for 2013.  (The paper is pay-walled at GSA but you can download the full paper here, 26.8 Mb.)

To set the stage for the research in this paper, here is some background taken from my post Origin of the Grand Canyon.  The Colorado Plateau initially tilted to the northeast and rivers, including the ancestral Colorado River, flowed in that direction into Utah and Colorado. Beginning about 18 million years ago, crustal stretching formed the Basin and Range province west and south of the plateau. Also around this time, plate tectonic adjustment began to tilt the Plateau toward the southwest.  Sometime around 10 million years ago, plate tectonic movement began to open the Gulf of California and a river at its north end began to cut northward. At about the same time, the northeastward flowing rivers of the Colorado Plateau reached the southern escarpment of the plateau and began to flow south forming lakes along what is now the course of the Colorado River. Actual cutting of the Grand Canyon probably began about 5.5 million years ago.

Now we take up the story as told by House, Pearthree, and Perkins in their paper.  Their story is based upon detailed stratigraphic mapping of the Bouse Formation and associated sediments in the Lower Colorado River valley, and upon tephrochronology, the precise dating of two layers of volcanic ash interspersed in the sediments.

In a nutshell, these authors propose that as the ancestral Colorado River cut through the Colorado Plateau and began to flow south, the water filled a series of basins from north to south, one at a time.  When the northernmost basin was filled, it breached the natural dam on its south side, and filled the next basin to the south.  This process was repeated until the river reached the Gulf of California.  The paper goes into great stratigraphic detail in support of this hypothesis which is illustrated in the graphic below.

Lower-Colorado-River-lakes

An earlier competing hypothesis proposes that an estuarine river cut northward from the Gulf of California, to form the Lower Colorado River.  This hypothesis was initially supported by the presence of limited marine fossils in the lowest member of the sediments along the river.  House, Pearthree, and Perkins counter this by proposing that:

“The lowermost Bouse lake would have encompassed an immense area extending from Parker Valley to the Chocolate Mountains and westward into a series of low-lying basins in the Mohave Desert. Recent hydrologic modeling suggests that it may have taken tens of thousands of years to fill this extensive lake to overflowing due to likely high rates of evaporation; consequently, the lake water could have become quite saline prior to spilling into the Yuma area. This might have allowed salt-water fauna to survive in the lake, but the mechanism for transportation of marine fauna into such a lake, if it existed, is disputed.”

In addition, they found that “strontium isotope ratios in Bouse carbonates throughout the extent of the deposit are more similar to modern Colorado River water than to seawater.” Also, the northward cutting river hypothesis requires over 1,800 feet of uplift along the river after the lake sediments were deposited.  Case closed  — for now.

The paper is well-illustrated with maps, cross-sections, and photographs.

See also:

Origin of the Grand Canyon

Grand Canyon age controversy heats up

EPA targets wrong cause of haze in Grand Canyon

As a followup to a previous post: “The EPA is destroying America,” I will focus today on the issue of haze in the Grand Canyon.

The EPA is targeting the coal-fired Navajo Generating Station (NGS) in regard to its emissions of nitrogen oxides. The EPA is insisting that NGS install “selective catalytic reduction” to control nitrogen oxides, at an added cost of $48 million per year, even though, just two years ago, the plant installed devices to control nitrogen oxides. This EPA action is of particular concern to Southern Arizona because NGS supplies the electricity to run pumps that provide water via the Central Arizona Project Canal (See more here.)

The story below demonstrates the perfidy of the EPA in its war on coal, its possible collusion with environmental groups, and there is even a connection to President Obama’s nominee for Secretary of the Interior. First, let’s look at the composition of haze in the Grand Canyon.

In the chart below, compiled from data produced by the Western Regional Air Partnership (part of the Western Governor’s Association), we see that nitrogen oxide emissions from electrical generating stations represent only about 1 percent of the constituents of haze in the Grand Canyon. Most haze is a combination of soot, dust and sulfates.

Grand canyon haze causes

In the pie chart above, we see that nitrates constitute about 8% of haze. The bar chart, if it is to proportional scale, indicates that nitrates from power plants (see asterisk) comprise about 13% of total nitrates, therefore nitrate contribution to total haze is about 1% (8% of 13% = 1%). See here for a clearer view of the chart. The EPA is, therefore, imposing a very expensive requirement to target less than one percent of the problem. As I’ve point out in another article, the EPA’s solution will have no effect on Grand Canyon haze (see: “EPA versus Arizona on regional haze issue“). It appears that the EPA attack on the Navajo Generating Station is part of the administration’s war on coal. See more on the Navajo Generating Station here and specifics on emissions control equipment here.

There have been many wild fires and controlled burn fires near the Grand Canyon, all of which contribute to the haze. In fact, the National Park Service (NPS) has a Facebook page on the subject on which they show several photos. Ironically, NPS celebrates smoke in the Canyon as “a photographer’s paradise::

“Fire has always played a role in the ecology of the high altitude forests of the Grand Canyon’s rims. The mixed conifer forests of the North Rim are dependent on fire. Natural fires burn low to ground, clearing out the down and dead wood on the forest floor. Fire creates a mosaic of burned and unburned vegetation, these openings and gaps on the landscape provide habitat for forest animals enriching the diversity of life a healthy forest needs. Prescribed fire is one tool park managers use to maintain a healthy forest ecosystem. Prescribed fires can smolder for days or even weeks creating smoke that lifts in high plumes during the day and sinks into the canyon at night. Smoke in the canyon may seem like a bummer, but in fact creates dynamic, beautiful vistas. Grand Canyon, regardless of conditions, is a photographer’s paradise.”

There is another curious connection. An environmental group, the National Parks Conservation Association (NPCA), has a hit piece on the Navajo Generating Station. Within that article is a video which shows a hazy Grand Canyon and the article strongly implies that the haze is due to emissions from the station. However, that video was filmed during the past summer when there were fires in the area contributing to the haze. The people featured in the video also belong to Diné Care, a Navajo environmental group that is fighting the generating station although the Navajo people as a whole value the station for jobs and income. Navajo President Ben Shelly, recently said in a public statement and in testimony before Congress, “I still think that the federal government has placed too much of an emphasis on visibility in contrast to the costs of compliance and the potential economic ripple effects. I sincerely hope that any ripple effects of this proposal will not result in immediate drastic impacts to our Navajo workers employed at NGS and the mine. Unfortunately, some federal rulemakings result in economic impacts that are hard to recover from. I hope this will not be the case here.”

I suppose that in the realm of political advocacy, truth is optional.

Another interesting confluence: President Obama has nominated Sally Jewell to be the next Secretary of the Interior. Ms. Jewell has been a long-standing member of the board of the National Parks Conservation Association. It’s a small world.

It seems that the EPA is again colluding with environmental groups and manufacturing an issue to serve a specific purpose.

P.S. The Wall Street Journal has an article on Sally Jewell here.

“The president knows he can rely on Ms. Jewell to do for the federal government exactly what she’s done at an activist level: Lock up land, target industries, kill traditional jobs.”

Update: CAP officials discuss impact of EPA action, see story in Arizona Daily Star here.

See also:

An open letter challenging the EPA on CO2 regulation

Electricity supply endangered by EPA regulations

BREAKING: Court tosses EPA Cross-state air pollution rule

EPA versus Arizona on regional haze issue

EPA war on coal threatens Tucson water supply

EPA fuel standards costly and ineffective

The EPA is destroying America

Obama’s undercover EPA regulations

EPA Admits CO2 Regulation Ineffective

EPA sued in federal court over illegal human testing

Grand Canyon age controversy heats up

The age of the Grand Canyon of Arizona has always been controversial and more fuel has been added to the controversy with the publication in Science on November 29 of a new study by researchers Rebecca Flowers and Kenneth Farley who say they have evidence that the Grand Canyon “was largely carved out by about 70 million years ago.” Their full paper is behind a pay wall but you can read the press release here. The contentious problem with that age is that the current Colorado River has been flowing along its present course and direction for only about 6 million years. For that story, see my post, written in 2011: “Origin of the Grand Canyon.”

The Arizona Geological Survey has weighed in on this controversy in their new Fall-Winter 2012 issue of Arizona Geology magazine with an article by Wayne Ranney, a geologist who has long studied the canyon and has written a book about it. What follows are excerpts from Ranney’s article.

“The new theory involves two very complex and complicated laboratory techniques that can reveal when the canyon’s rocks were brought close to the surface. Using tiny apatite crystals collected from the basement rocks in the canyon (Vishnu Schist or Zoroaster Granite), the information yielded two different stories, one for the history of the western Grand Canyon and the other for the eastern canyon, where most tourists see the gorge. The results said that western Grand Canyon (downstream from Lava Falls) was cut to within a few hundred meters (about 1,000 feet) of its present depth by 70 Ma [million years ago]. The second story reported that the eastern area was the site of a canyon of similar proportions to the modern canyon by 55 Ma, and cut in Mesozoic rocks now completely eroded away. Incredibly, the western canyon was cut by a river that flowed exactly opposite to the modern Colorado River and the researchers call this the California River.”

Reread the paragraph above. It says that in the eastern canyon area, a canyon equal to the current one was formed, then disappeared.

Ranney continues:

 “When the Cal Tech group began their study they assumed that the apatite samples would reveal that Grand Canyon’s rocks were buried in unequal amounts of overlying rock – unequal because the canyon today has 5,000 feet of relief and the lower samples should have been buried under more material than those collected from near the top.”

That concept is shown in figure 1. The red dots show the relative position where Flowers and Farley collected their samples.

GC expected

“After running the laboratory technique the samples produced surprising results to the researchers. They showed that no matter from what depth the samples were collected, they all appeared to have been buried under equal amounts of overlying rock [figure 2]. When the tops of the blue arrows are connected here, they reveal a canyon-like topography in eastern Grand Canyon about 70 Ma. Below is a diagram [figure 3] that shows their interpretation of the data – a gorge of similar proportions was cut into the Mesozoic rocks that are now stripped back to the modern Echo and Vermilion Cliffs.”

 

Ranney opines that the laboratory technique used by Flowers and Farley “is not as evolved as one might hope for. Some assumptions are made that could result in different outcomes.”

GC 2-3

Ranney also notes: “The evolutionary history of the Colorado River shows that its exact course through the canyon to the Gulf of California was accomplished in only the last 6 million years.” He emphasizes, however, that the age of the Colorado River is not necessarily the same as the canyon, “the age of its [the river’s] ancestors or some early incarnation of the canyon need not be so strictly confined.”

Read Ranney’s entire article here.

Check out other stories in Arizona Geology Magazine here.

For more geology stories, see my Article Index page.

EPA versus Arizona on regional haze issue

A previous post: EPA war on coal threatens Tucson water supply, examined the consequences of EPA regional haze regulations at the Navajo Generating Station, near Page, Arizona, on our water supply. That station supplies all the electricity needed to pump water from the Colorado River to Tucson via the Central Arizona Project (CAP). It now seems that the EPA is after other coal-fired plants in Arizona.

As a result of the previous post, I received an email from William Yeatman, Assistant Director, Center for Energy and Environment, at the Competitive Enterprise Institute. Mr. Yeatman is an expert on the issue of haze and power plant emissions. (See two of his publications on the matter here and here.)

Mr. Yeatman wrote me:

“Regional Haze is an aesthetic regulation pursuant to the Clean Air Act. Its purpose is to improve visibility at federal National Parks and Wilderness Areas. It is the only aesthetic regulation in the Clean Air Act. This point bears repeating: Unlike every other regulation established by the Clean Air Act, Regional Haze has nothing to do with public health.

Another hallmark of the Regional Haze regulation is State primacy. Whereas EPA is the lead decision-maker when it comes to setting public health standards pursuant to the Clean Air Act, the Congress intended for the States to render determinations on Regional Haze.

After countless hours of deliberation by State officials and significant public participation, Arizona submitted a Regional Haze implementation plan to the EPA in February 2011. Despite the Congress’s intention that States take the lead on Regional Haze decision-making, EPA Region 9 in mid-July disapproved Arizona’s submission, and proposed a federal implementation plan in its stead.”

Specifically, in addition to harassing the Navajo Generating Station near Page, Arizona, the EPA found fault with Arizona’s proposed regulations for control of nitrogen oxides (NOx) for the Apache Generating Station near Cochise, Arizona; for Cholla Power Plant near Joseph City, Arizona, and for the Coronado Generating Station near St. Johns, Arizona.

Yeatman writes:

“For all three power plants, Arizona chose NOx controls known as ‘Low Nitrogen Burners.’ EPA, however, wants to impose NOx controls known as ‘Selective Catalytic Reduction.’ The difference in price is significant—EPA’s plan is almost $48 million per year more expensive than the State’s plan [emphasis added]. Of course, these costs would be passed along to Arizona ratepayers in the form of higher utility bills.”

Yeatman modeled the expected results comparing the Arizona proposal versus the EPA proposal. The effect on regional haze is shown in the graphic below. Can you see any difference?

GC-haze-comparison

The extra $48 million per year that the EPA requirements would impose does not seem to provide any additional benefit, only addition pain to Arizona ratepayers.

Mr. Yeatman concludes: “Despite the Congress’s intent that the State’s have primacy on Regional Haze, the EPA already has imposed four Regional Haze federal implementation plans on New Mexico, Oklahoma, North Dakota, and Nebraska. EPA’s preferred plans cost almost $400 million more than the States’ plans. Not one of EPA’s imposed Regional Haze plans resulted in a perceptible improvement in visibility.”

It seems that the EPA is a rogue agency that imposes regulations just because they can. Few of their regulations in this matter have any scientific basis and the EPA seems to ignore economics.

See also:

EPA war on coal threatens Tucson water supply

EPA fuel standards costly and ineffective

EPA, ethanol, and catch 22

EPA may change Dioxane standards in Tucson water

EPA Admits CO2 Regulation Ineffective

Electricity supply endangered by EPA regulations

Clean Coal: Boon or Boondoggle?