Category: Geology

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The Geology of Canyonlands National Park

Chesler Park
Canyonlands National Park
Photo Courtesy and Copyright Kurt Repanshek, Photographer

Chesler Park
Canyonlands National Park
Photo Courtesy and Copyright Kurt Repanshek, Photographer

Baked by time like some multi-layer geologic tort, Canyonlands National Park in southeastern Utah features a landscape cut by canyons, rumpled by upthrusts, dimpled by grabens, and even pockmarked, some believe, by ancient asteroids.

Just outside of Moab rises a kaleidoscope of tilted and carved geology laid down over the eons. There’s the red and white Cedar Mesa sandstone, the grayish-green Morrison Formation, pinkish Entrada sandstone, and tawny Navajo sandstone, just to name some of the geologic layers. Stacked like pancakes, they help make Canyonlands the most rugged national park in the Southwest and, quite possibly, if you find yourself deep in the park’s Maze District, in the entire Lower 48 states.

In each of the park’s districts — Island in the Sky, Needles, Maze and Horseshoe Canyon — the remarkable effects of geologic time and its endless erosion on this sedimentary landscape rise about you.

If you could turn back the geologic clock, you would see the landscape flooded by oceans, crisscrossed by rivers, covered by mudflats and buried by sand. At various times through the millennia, the climate has resembled a tropical coast, an interior desert, and everything in between.

For hundreds of millions of years, material was deposited. Layer upon layer of sedimentary rock formed as buried materials were cemented by precipitates in the ground water. Each layer contains clues to its origin, such as patterns or fossils, which reveals the environment when it was deposited. For example, the colorful Cedar Mesa Sandstone occurred when periodic floods of iron-rich debris from nearby mountains inundated coastal dunes of white sand.

Along with sedimentation, movements in the earth’s crust altered surface features. The North American continent migrated north from the equator and the local climate and environment here changed dramatically.

Peer into the ragged maw of Canyonlands from the Island in the Sky District on the northern end of the park, and it’s no mystery how the park came by its name.

Spend the night at the Squaw Flat Campground in the Needles District and a morning hike into Chesler Park surrounds you with Creamsicle-hued minarets towering high above, like a king’s crown.

Though Canyonlands covers less than 350,000 acres, which is less than one-seventh the size of Yellowstone National Park, it feels much larger. No doubt it’s the park’s vastness and openness — you won’t find any forests here. Indeed, one old timer said that, “On a clear day, you can see the back of your own head.”

Spend a few minutes contemplating the natural forces, and the hundreds of millions of years that laid down these sediments and compressed these layers of rock. It’s really only recently that these layers have eroded to form the remarkable landscape seen today in Canyonlands National Park.

For Wild About Utah and National Parks Traveler, I’m Kurt Repanshek.

Credits:
Image: Courtesy and Copyright Kurt Repanshek, www.nationalparkstraveler.com
Text:     Kurt Repanshek, NationalParksTraveler.com.


Additional Reading:

Canyonlands National Park, National Parks Service,

Exploring The Parks: Musings From Island In The Sky At Canyonlands National Park, NationalParksTraveler.com Article – Lee Dalton – 06/24/2014

Exploring The Parks: Musings From The Needles District In Canyonlands National Park, NationalParksTraveler.com Article – Lee Dalton – 06/19/2014

Reflections Of Time In Canyonlands, NationalParksTraveler.com Article – Lee Dalton – 06/19/2014

https://www.nationalparkstraveler.com/search/apachesolr_search/canyonlands, NationalParksTraveler.com Canyonlands Articles

Hylland, Rebecca, What are Igneous, Sedimentary & Metamorphic Rocks?, Glad You Asked, Utah Geological Survey, https://geology.utah.gov/map-pub/survey-notes/glad-you-asked/igneous-sedimentary-metamorphic-rocks/

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A Safari through Utah’s Ice Age

Wave-cut platforms from
Lake Bonneville preserved on
Antelope Island, Great Salt Lake, Utah.
Photo Courtesy Wikimedia, Mark A. Wilson (Department of Geology, The College of Wooster), Photographer

Ground sloth of the Pleistocene
Paramylodon harlani
Texas Memorial Museum
University of Texas at Austin.
Photo Courtesy Wikimedia
Licensed CCA Share Alike 3.0 Unported

Lake Bonneville compared to the
State of Utah.
Photo Courtesy https://wildlife.utah.gov/gsl/history/


Hi, I’m Ru Mahoney with Stokes Nature Center in Logan Canyon. As winter approaches I find myself anticipating the first really good snow, when our valley floors and mountain passes will be transformed overnight, relinquishing autumn’s riot of color for a glacial monochrome. As little as 12,000 years ago winter white was Utah’s perennial favorite, donned at the launch of the Pleistocene Epoch, a roughly 2 million year long period (give or take 10,000 years) marked by widely recurring glaciations.

The west has a reputation for being vast, but Ice Age Utah was even bigger. The mountains where higher and sharper. And the Great Salt Lake was submerged beneath the glacial waters of Lake Bonneville. At its largest, this massive body of water covered 20,000 square miles and was more than 980 feet deep. To put that into perspective, that measures about 9.5 million football fields wide by 4.5 Salt Lake Temples deep. And the Ice Age wildlife? Well it was much more akin to an African safari than anything you’re likely to find on your favorite shoreline trail these days.

The megafauna of Pleistocene Utah included a menagerie of beasts that are the stuff of legend. Familiar species like bison and big-horn sheep grazed among herds of mammoths and mastodons. Camels and horses – destined for extinction in North America – were the prehistoric prey of dire wolves and saber-toothed cats. Giant ground sloths the size of modern day elephants stood on two powerful hind legs to browse on shoreline foliage. And herds of muskoxen kept a wary eye on Arctodus, the Short-faced bear, a formidable predator more than 50% larger than any bear species living today.

The last 30,000 years of Utah’s Ice Age were characterized by increasingly volatile shifts in climate. The changing norms in temperature and abundance of liquid water created cyclical periods of transitioning habitat. Forests and forest dwellers gave way to deserts and their specialist species, before shifting back to forests again, all in mere millennia. While nomadic and highly adaptable species like muskoxen eventually moved north to more stable climates, the less adaptable fauna of the Ice Age were increasingly relegated to sharing shoreline habitat diminished by the swollen banks of Lake Bonneville.

As fluctuating glaciers pushed southward and then retreated, canyons like Big and Little Cottonwood were gouged into existence. Spring and summer glacier melt carried an abundance of freshwater into the lake, sometimes sweeping along with it the remains of prehistoric animals that had not lasted through the winter, laying them to rest in shoreline deltas where their fossilized remains are now uncovered and studied in alluvial sediment. For many of Utah’s Ice Age animals, the end of the Pleistocene brought extinction.

Today the ancient shoreline of Lake Bonneville is one of the most distinguishable geological features along the Wasatch front. This “bench”, as it’s now commonly known, is easily identifiable in cities all along the Wasatch and frequently boasts fine homes and even finer views. Which might go to show that lakeside property retains its value whether the lake is still there or not. So as you enjoy a winter hike or cross country ski along a shoreline trail this season, think about Utah’s last Ice Age and how our rich fossil record, with some of earth’s largest land mammals, paints a picture of an even wilder west.

For Wild About Utah and Stokes Nature Center, I’m Ru Mahoney.

Credits:
Image1: Courtesy Wikimedia, Mark A. Wilson (Department of Geology, The College of Wooster), Photographer
Image2: Courtesy Wikimedia,as licensed through Creative Commons Attribution-Share Alike 3.0 Unported
Image3: Courtesy https://wildlife.utah.gov/gsl/history/
Text:     Ru Mahoney, Stokes Nature Center in Logan Canyon.

Additional Reading:
https://geology.utah.gov/popular/general-geology/ice-age/ice-age-animals-of-utah/

https://serc.carleton.edu/vignettes/collection/37942.html

https://hugefloods.com/Bonneville.html

https://geology.utah.gov/surveynotes/archives/snt42-3.pdf

https://geology.utah.gov/surveynotes/articles/pdf/pleistocene_fossils_42-3.pdf

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Cryptobiotic Soil Crusts

Click to view larger image of Cryptobiotic Soil Crust, Photo Courtesy and Copyright Mark Larese-Casanova
Cryptobiotic Soil Crust
Photo Courtesy & Copyright 2009
Mark Larese-Casanova

Hi, this is Mark Larese-Casanova from the Utah Master Naturalist Program at Utah State University Extension.

Looking out over a Utah desert, we might see relatively few plants- perhaps some sagebrush, maybe a few junipers or Joshua trees, or even some small wildflowers or cacti. What is less noticeable, though, is the living soil crust that holds this entire landscape together. It’s not just sand, but rather an important and vast partnership between bacteria, lichens, algae, and fungi. These soil crusts are often referred to as ‘cryptobiotic’, which means ‘living in suspended animation’. This is a fitting description, considering that water can be so rare in Utah’s deserts.

Cyanobacteria, which is often called blue-green algae, is the backbone of cryptobiotic soil crust. Vast networks of long, microscopic filaments of cyanobacteria and fungi grow in length when they are wet, and leave behind a casing that literally binds the soil together. So, what might otherwise be loose sand not only is less likely to be washed away by water or blown away by wind, but also is able to hold much more water for plants.

Click to view larger image of Cryptobiotic Soil Crust, Photo Courtesy and Copyright Mark Larese-Casanova
Cryptobiotic Soil Crust
Photo Courtesy & Copyright 2009
Mark Larese-Casanova

Cyanobacteria is also extremely useful to desert landscapes for its ability to take Nitrogen out of the air and make it available to plant roots in the soil. Desert soils typically have relatively low nutrients, so this is especially important to desert plants.

In many Utah deserts, cryptobiotic soil crusts can cover up to 70% of the ground surface. Old soil crust can often look like small mountain ranges with black or white peaks inhabited by lichens or mosses. The little valleys in between the tiny mountains of crust are perfect spots for the seeds of desert plants to grow. Over time, the above ground crust can grow up to ten centimeters, or four inches, thick!

However, cryptobiotic soil crust grows at an alarmingly slow rate of about one millimeter per year. So, any soil crust that is disturbed can take a very long time to recover. Depending on the amount of moisture a desert receives, it can take anywhere between 20 and 250 years for soil crust to grow back.

Next time you’re out in the desert, kneel down and have a close look at the telltale peaks and valleys of cryptobiotic soil crust. If you bring a magnifying glass, you just might be able to see some of the lichens and mosses. Be sure to stay on trail, though, and whatever you do, don’t bust that crust!

For Wild About Utah, I’m Mark Larese-Casanova.

Credits:

Images: Courtesy and copyright Mark Larese-Casanova
Text:     Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.
Additional Reading:

US Department of Interior. 2001. Biological Soil Crusts: Ecology and Management. Bureau of Land Management Technical Reference 1730-2., https://www.blm.gov/nstc/library/pdf/CrustManual.pdf
Rosentreter, R., M. Bowker, and J. Belnap. 2007. A Field Guide to Biological Soil Crusts of Western U.S. Drylands. U.S. Government Printing Office, Denver, Colorado., https://www.soilcrust.org/

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Defining the Great Basin

Willow Creek North of Wells, NV. Sagebrush at mid-distance. Route of the California Trail used by pioneers.
Willow Creek north of Wells, NV.
Sagebrush at mid-distance.
Route of the California Trail
used by pioneers.

Courtesy & Copyright
Jim Cane, Photographer

Lupines amid sagebrush north of Wells, NV. Ruby Mountains in backgroundLupines amid sagebrush
north of Wells, NV.
Ruby Mountains in background
Courtesy & Copyright
Jim Cane, Photographer

Map delineating the Great basinMap delineating the Great basin
Courtesy Wikimedia, KMusser, Artist
Ref: wikipedia.org/wiki/Great_Basin


The Great Basin is aptly named.  Twice the size of Kansas, it stretches from the watersheds of the Columbia and Snake rivers south to that of the Colorado, and from the crests of the Sierra Nevada and southern Cascades eastward to the Wasatch front.  The Western explorer John Fremont coined its name in 1845.  The rivers and streams of the region that Fremont had seen all ended in sinks, marshes or lakes. None flowed to the Pacific Ocean.  He confirmed this on meeting Joseph Walker at Mountain Meadows in Utah.  Walker had traveled more of the basin’s western margins, dispelling  rumors of a river traversing the Sierra Nevada.  Precipitation that falls in the Great Basin stays in the Great Basin; water leaves only as vapor.  This is the hydrographic Great Basin.

How else to view the vast region between the Rockies and the Sierra Nevada? Geologists speak of the “Basin and Range Province”, so named for its valleys and the towering ranks of north-south mountain ranges that march across the landscapes of Nevada and edges of adjacent states. Unlike the upthrust Rockies and Sierra Nevada, Earth’s crust in the Great Basin appears to be spreading, to be pulling apart. The tilted escarpments of the Wasatch front are the easternmost evidence of this crustal deformation that has built the Basin and Range Province.

Botanists delimit the Great Basin by the hardy flora that clothes this rugged landscape. Great Basin plants tolerate freezing winters and parched summers, and in the valleys, soils of varying salinity.  The so-called Sagebrush Ocean fills many of the basins, as do other shrubs, such as shadscale and greasewood.  Upslope, these give way to juniper woodlands, often mixed with piñon pine.  This floristic Great Basin reaches eastward to central Utah and the Wasatch front, beyond which trees and other plants of the Rockies make their appearance.

The boundaries of all three concepts for the Great Basin — hydrographic, geologic and floristic — largely coincide.  Each recognizes the distinctive attributes of the Great Basin that set it apart from neighboring regions.  The Great Basin is readily recognizable to the trained eye, whether looking at satellite images, river courses, or the native plant communities encountered on a simple walk.

Credits:
Images: Jim Cane
Map: Courtesy Wikimedia, KMusser, Artist, licensed under Creative Commons Attribution-Share Alike 3.0 Unported
Text: Jim Cane

Additional Reading

Frémont, John Charles. 1845. Report of the exploring expedition to the Rocky Mountains in the year 1842 and to Oregon and North California in the years 1843 – 44. Printed by order of the Senate of the United States , Gales & Seaton, 693 pages. –available as a Google eBook scanned from the original published book Grayson, Donald K. 1999. The desert’s past : a natural prehistory of the Great Basin. Smithsonian Institution Press, Washington D.C., 356 pages. –an exceptionally readable, thorough and authoritative overview of the Great Basin, with many maps, photographs and illustrations.https://books.google.com/books?id=W8ICAAAAMAAJ

Intermountain Regional Herbarium Network. searchable plant database representing multiple holdings of herbaria at universities in Utah and Nevada, with maps, images and more https://swbiodiversity.org/seinet/projects/index.php?proj=10

McPhee, John. 1981. Basin and Range. Farrar, Straus, Giroux, New York. 215 pages. –the first of the author’s many engaging books about geology. https://www.amazon.com/Basin-Range-John-McPhee/dp/0374516901