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Visiting Zion National Park: Part II   7 comments

The area around Zion remains sparsely populated enough to get a feel for what ancient people saw as they passed through.

This continues the series on Zion National Park in Utah.  We’ll focus this time on the history of American Indians in this part of the desert southwest.  Check out Part I for Zion’s pre-human history – its geology.  If you plan on visiting Zion, or any other place, with photography being a big deal for you, I recommend learning about the place instead of perusing photo after photo of it.

In other words, find out what’s interesting about to you about the place.   Try to tailor your visit so you hit spots that feature those interesting aspects, even if they’re outside of your planned destination (in this case the park).  Resist the temptation to visit too many spots based merely on your admiration for the photos others have captured there.  Sorry, end of lecture!

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VISIT THE MUSEUM

If you’re interested in the natural and human history of Zion, you’d do well to visit an interesting little museum upon arrival.  The Zion Natural History Museum is located on the left not far past the west entrance.  Turn left just after passing the turnoff for the campground, which is on the right.  While worthwhile, by far most cultural artifacts are not on display here.  They are housed in Springdale at park headquarters in a large collection of more than 20,000 items.

If you have a keen interest, you can make an appointment to see this collection.  Just email the curator at miriam_watson@nps.gov.  You’re not guaranteed to get in, and it may help to have a group so they make the time for you.  Your goal is to find an NPS staff member with time to give you a personal (and free) tour of the collection.  You can learn some basics by reading in the Park Service’s website for Zion, along with other sites (go beyond Wikipedia!).  But if you can make time for the hands-on approach, you’ll get much more out of it.

View up Zion Canyon at dusk.

View of East Temple at dusk.

ANCIENT TRAVELERS

The first people in North America were hunters traveling with and hunting herds of wooly mammoths, gathering plants for food and medicine along the way.  Most of the evidence we have for these people comes from their spear points and other stone tools like scrapers.  The points, called Clovis and (slightly later) Folsom, are distinctively fluted and usually associated with mammoth remains at kill sites, tagging them as belonging to these ancient hunter/gatherers even where direct dating is impossible (which it usually is).

Although to my knowledge there have been no Clovis or Folsom sites documented for Zion itself, there have been points found north and west of the park.  So it’s reasonable to assume these wanderers walked the canyons and plateaus of what would thousands of years later become known as Zion National Park.  The fact that these canyons are subject to dramatic flash floods means that archaeological evidence tends to be swept away.

Somewhat more evidence ties later hunter/gatherers to the Zion area about 8000 years ago.  These hunter/gatherers, who hunted bison and smaller mammals (mammoths, sloths and other ice-age megafauna had been hunted to extinction), may have even set up seasonal camps.  But there are precious little remains to go off of.

Beaver-tail (or prickly pear) cactus with dried fruits growing in east Zion. A staple of American Indians for thousands of years, the fruits were eaten fresh and raw or made into a jelly. The nopales (cactus pads) were sliced and eaten, and also used to treat wounds and swelling.

Beaver-tail (or prickly pear) cactus with dried fruits growing in east Zion. A staple of American Indians for thousands of years, the fruits were eaten fresh and raw or made into a jelly. The nopales (cactus pads) were sliced and eaten, and also used to treat wounds and swelling.

BASKET-WEAVERS & ANCESTRAL PUEBLOANS

There is evidence of these ancient farmers at Zion.  Basket-weavers, known for their baskets woven of willow and other plants, lived here between about 300 B.C. and 500 A.D.  Since their artifacts degrade easily, they are very rare.  Not much evidence was left behind at Zion, but what there is points to early farming.  These people were succeeded by two groups in the so-called Formative Period from 500 to 1300 A.D.

PAROWAN FREMONT

These people lived in the north of the region up on the plateaus near springs.  Some farmed a cold-tolerant form of corn, some led a more mobile hunting/gathering lifestyle, and some were semi-nomadic.  These hunters did not use bows and arrows.  Rather they threw spears (or arrows) using an ingenious implement called an atlatl.  Atlatls extend the reach of your arm, increasing leverage and speed greatly.  I’ve tried them and they do indeed fling the arrow fast.  But I realized right away that to gain accuracy would require much practice.

Both of these groups, left behind rock art.  It’s very sad that much of this art has been vandalized by clueless visitors.  More remote sites like the Cave Valley petroglyphs off of Kolob Terrace Road are in much better shape.  But even these have been damaged.  As a result, good luck getting any ranger to tell you how to get to this rock art.  The Parowan Fremont sketched unique art characterized by anthropomorphs with triangular or trapezoidal bodies and limbs.

Fremont rock art is characterized by anthopomorphic figures with blocky triangular bodies.  The squiggly line at left represents a journey.

VIRGIN ANASAZI

Farming the southern canyon bottoms were an Ancestral Puebloan group known as the Virgin Anasazi.  As the name “puebloan” suggests, they were sedentary, occupying small settlements.  They were farmers who left behind food storage sites (see below) along with stones for grinding grains called manos and metates.  Later on the farmers began building stone and masonry structures alongside their partly underground dwellings and storage sites.

The two groups evidently had some contact, even though they lived in different environments. They traded tool-making stone and very likely food and medicinal plants as well.  There is no evidence for conflict between them, though some suggest the arrival of Southern Paiute and other tribes from the north may have had something to do with their leaving the area.

ARCHAEOLOGY TRAIL

There is an ancient grain-storage site you can hike to from Zion’s visitor center.  Ask a ranger for directions to the trailhead for the Archaeology Trail.  It’s short, steep and you get a good view of the canyon.  There is not much left of the 1000 year-old Virgin Anasazi site, so get the ranger to give you a few tips to see what there is to see.  But it’s definitely a great way to stretch your legs when you stop at the visitor center.  You can ponder the reasons why the Ancestral Puebloans left their dwellings so abruptly, almost as if they intended to return after visiting friends or relatives elsewhere.

Frozen dew at the end of autumn, Zion National Park.

Frozen dew at the end of autumn, Zion National Park.

RETURN OF THE WANDERING LIFESTYLE

The main tribe to enter the area from the north were the Southern Paiute.  Arriving around 1100 B.C., they obviously coexisted with the nearby farmers for some 200 years.  But their lifestyles were very different.  They hunted and gathered plants, occupying pit-houses and other semi-permanent structures only seasonally.  As such, these nomadic people were well equipped to handle the series of droughts interspersed with catastrophic flooding that began on the Colorado Plateau about 1300 A.D.  They remained while the Ancestral Puebloans and Fremont people left.

These tribes were the ones who greeted white Euro-Americans in the late 1700s.  And when I say greet I don’t necessarily mean warmly.  Many died from diseases brought west by the invaders; the rest were defeated and placed on reservations.  Such is the march of “progress”, but that’s the subject for next post.  We’ll continue with the story of Brigham Young and his flock of Mormons.  Have a great weekend!

The setting sun turns East Zion's cliffs orange above a vernal pool.

The setting sun turns East Zion’s cliffs orange above a vernal pool.

Visiting Zion National Park: Part I   20 comments

Zion Canyon from Bridge Mountain.

Zion Canyon from Bridge Mountain.

I’m going to change pace and do a short travel series: an in-depth look at Zion National Park.  I’ve not done one of these for a long time.  As usual I’ll start with Zion’s natural history, including geology in this post.  Then I’ll go on to human history and life on display at Zion.  I’ll finish with travel logistics and recommendations for various visit lengths, focusing of course on photography.

If you haven’t yet visited Zion, this series will be an in-depth introduction with tips, but without presuming to tell you exactly where and how to photograph the park.  If you’ve been to Zion before, you will learn some interesting stuff about the park and probably find out about one or two out-of-the-way photo spots.

But mostly this is about background knowledge.  I strongly believe the more you know about a place the better your experience and photos will be.  Though my posts are always heavily illustrated, I hope you’ll try to forget the pictures when you go out yourself.  Do your own thing and get pictures that represent your own unique take on the park.

East Temple from just east of the tunnels.

East Temple from just east of the tunnels.

REGIONAL SETTING

Zion National Park lies in southwestern Utah, in an area called Dixie.  That term is normally associated with the southern states (Alabama, Georgia, etc.).  Utah’s Dixie is certainly where the climate is warmest in the Beehive State.  But it’s much drier than the humid South.  Zion is at the southwestern edge of the Colorado Plateau, that huge regional uplift of sedimentary rocks that covers parts of four states and defines much of the dramatic scenery of America’s desert southwest.

THE GRAND STAIRCASE

Zion is also on the western edge of a geologic feature called Grand Staircase.  This is a large series of cliff-forming sedimentary layers that steps downward from north to south.  Some of the area’s highest and youngest rocks are to the north near Bryce Canyon while some of the lowest and oldest rocks are exposed to the south in Grand Canyon.

But the rim of that last southern step (it’s a doozie!) tops out at 8800 feet in elevation on the north rim of the Grand Canyon.  That’s very similar to the top of Bryce (the northern step) at 9100 feet.  So the Grand Staircase not so much steps downward in elevation but in geology.

BREAKS & CANYONS

Zion Canyon, centerpiece of the park, plus Cedar Breaks to the north, are located where the land “breaks” downward off the high eastern plateaus of south-central Utah to meet the lower deserts of SW Utah and southern Nevada.  These breaks are also known as the Hurricane Cliffs, which continue south into NW Arizona.

The towns in this part of Utah, largest of which is St. George, are situated near the foot of this dramatic sandstone escarpment, at a relatively low elevation compared with much smaller burgs up in the plateau country to the east.  The Virgin River and its tributaries have cut generally SW-facing canyons down through the escarpment.  The most dramatic of these is Zion Canyon.

The Hurricane Cliffs 'break' down off the Colorado Plateau here at Kolob Canyons, part of Zion National Park, Utah.

The Hurricane Cliffs ‘break’ down off the Colorado Plateau here at Kolob Canyons, part of Zion National Park, Utah.

The lower terrain near St. George, Utah is exemplified by Snow Canyon State Park, but the land continues to drop to the south and west.

The lower terrain near St. George, Utah is exemplified here at Snow Canyon State Park, but the land continues to drop to the south and west.

GEOLOGIC HISTORY

THE GREAT JURASSIC DESERT

The most prominent formation at Zion is Navajo Sandstone.  It forms most of the named dome-like features at Zion, such as the Patriarchs, the Sentinel, and White Throne.  The Navajo, which is generally a whitish sandstone, preserves record of an ancient desert.  This desert, which existed in the Jurassic age (dinosaur times), was dominated by enormous sand dune fields (ergs) similar to today’s Sahara Desert.

You can tell the rocks are ancient sand dunes because of cross-bedding.  Take a good look at the sandstone walls at Zion and notice the lines angled at about 35 degrees to the main rock layers, which are nearly horizontal.  A great place to see cross-bedding is at Checkerboard Mesa near the park’s east entrance, but you’ll see it everywhere in East Zion east of the tunnels.  The rocks behind the sheep below show cross-bedding.

Desert bighorn sheep at East Zion.

Desert bighorn sheep at East Zion.

The desert sands of the Navajo formed when plate tectonics, beginning a couple hundred million years ago, dragged this area north from equatorial to much drier latitudes in the vicinity of the Tropic of Cancer (30 degrees north).  This is the latitude, both north and south of the equator (Tropic of Capricorn), where the world’s major deserts are still found.

Also contributing to desertification in the Jurassic were the mountains building to the west of Zion in Nevada and California.  These ranges, which were the result of tectonic collision at the western edge of North America, are now gone, eroded away.  But in the Jurassic they formed an effective rain-shadow, blocking rains coming off the Pacific and helping to dry things even further.

A side-canyon in East Zion has a stream carrying sand eroded from the Navajo Sandstone, itself built from dune sands eroded from a long-gone ancient mountain range.

A side-canyon in East Zion has a stream carrying sand eroded from the Navajo Sandstone, itself built from dune sands eroded from a long-gone ancient mountain range.

PRE-DESERT TIMES

There is more than Navajo Sandstone at Zion, however.  The Virgin River has cut so deeply into the rocks that, despite the great thickness of the Navajo, other formations are visible beneath it.  These record shallow seas, meandering streams and floodplain environments.  For example, the Kayenta and Moenave Formations below the Navajo are reddish stream deposits formed in climates that changed from subtropical (for the older Moenave) to semi-arid (for the overlying Kayenta).

These older formations form the rubbly slopes and red cliff bands low on Zion’s canyon walls.  They’re also prominent above the town of Springdale, and up on Kolob Terrace Road.  Solid red cliffs of Kayenta, formed at the edge of that great encroaching desert, lie directly beneath the hard white sandstones of the Navajo.

If you gain a high vantage point you may notice the red “hats” or caps on top of the Navajo Formation’s highest white domes.  These belong to the Temple Cap and Carmel Formations, at 160 million years the youngest rocks at Zion.  Their reddish color is clue to wetter conditions returning in the late Jurassic.  A warm sea even invaded again, this signaled by limestones of the Carmel Formation.

The Navajo Sandstone is in places stained with iron oxide, where fractures have allowed fluids to penetrate the rock and move iron from other formations.

The Navajo Sandstone is in places stained with iron oxide, where fractures have allowed fluids to penetrate the rock and move iron from other formations.

UPLIFT & EROSION

Time didn’t stop after deposition of the Navajo and other Jurassic rocks at Zion.  Sedimentation continued into the Cretaceous and beyond; yet, save for an important exception (see below), younger rocks of the Zion region have been stripped away by erosion and transported down the Colorado River into the Pacific Ocean.

Erosion is a big deal at Zion.  The Colorado Plateau continues to be shoved upward by tectonic pressures (a 5.8 magnitude earthquake shook Zion in 1995).  Over time, this uplift has increased river gradients dramatically, resulting in very active erosion by streams and rivers as well as landslides.  Wind has helped sculpt the landscape.

Basaltic lava flows form a stark contrast with iron-stained Navajo Sandstones.

Basaltic lava flows form a stark contrast with iron-stained and dune cross-bedded Navajo Sandstones.

YOUNG LAVA FLOWS

If you drive up to Lava Point on the Kolob Terrace Road, you will notice dark lava flows, which flowed out of vents that opened up as this area began to stretch (rift), starting about 2 million years ago.  This young age places the lava flows (which being basalt were quite fluid) in the Ice Ages, which were fairly wet times at Zion.  Think about the terrain at that time, which was dramatic canyon country as it is today.

This combination of climate, active basaltic volcanism and topography tells you something must have happened (and it did!):  lava-dammed lakes.  If you hike the Subway, a lake formed in that canyon when lava dammed the Left Fork; it extended all the way up to the Subway itself.  If you’re observant you’ll notice fine lake muds and silts laid down by this lake.  You pass right by them when you’re hiking back out of the canyon.

By the way, let’s put some numbers on this story.  Most of what you see at Zion is between about 200 and 160 million years old, placing it squarely in the Mesozoic Era, age of dinosaurs.  Less noticeable rocks beneath these are as old as 250 million years, while the young lavas are between 1.5 and 200,000 years old.

Dusk falls on the Kolob Terrace, with a large dome of Navajo Sandstone catching the glow above red Kayenta sandstones. Footprints of sauropods (huge plant-eating dinos) have been found in the red formation.

Dusk falls on Kolob Terrace, with a large dome of Navajo Sandstone catching the glow above steep red and mauve slopes of the Kayenta.  Beneath that in the foreground are brick-red rubbly cliffs of the Springdale Member of the Moenave Formation. Footprints of sauropods (huge plant-eating dinos) have been found here.

TROPICAL SEAS AT ZION?

The older pre-dinosaur strata is worth mentioning because it is prominent at nearby attractions, such as Grand Canyon to the south of Zion.  Most prominent of the area’s oldest rock formations is the Kaibab.  It dates back to Permian times about 260 million years ago.  In these ancient times, an embayment of the ocean we call Panthalassa lapped at the edge of the world’s only landmass, the supercontinent Pangaea.  At that time this region, later to become Utah and Arizona, was near the equator.

The Kaibab is mostly limestone, formed in warm, shallow seas.  It’s visible in places low along the Virgin River within the park and also dramatically in the Hurricane Cliffs near the town of Hurricane and north along the east side of I-15.  It’s interesting to realize that the Kaibab, which hides low in Zion’s deep canyons, forms the high rim of Grand Canyon to the south.  This tells you something about the layout of the Grand Staircase.

Thought I'd throw in a shot from the Grand Canyon, because the Kaibab Limestone is exposed so well here at Toroweap on the North Rim.

Thought I’d throw in a shot from the Grand Canyon, because the Kaibab Limestone is exposed so well here at Toroweap on the North Rim.

THE SENTINEL SLIDE

More recently during the Ice Ages, the climate at Zion was wetter than today’s.  The Virgin and other rivers carried more water, thus flash-flooding was more frequent and violent.  Four thousand years ago a huge landslide blocked the Virgin River and formed a 350 foot-deep lake in Zion Canyon.  This enormous slump block came off The Sentinel, so it’s called the Sentinel Slide.

The lake extended from Canyon Junction all the way to Angel’s Landing.  Sediments settled out on the canyon floor, partly filling its natural V-shape.  The river could not be stopped for long of course, and the natural dam was eventually breached.  The resulting flood drained the lake and formed the V-shaped inner canyon between Court of the Patriarchs and Canyon Junction.

So now you know why Zion Canyon is flat-bottomed; it’s the old lake-bed.  You can see the remains of the Sentinel Slide above you on the left as you drive up-canyon.  For a closer view hike or go on a horse-back ride on the Sand Bench Trail, which climbs up on top of the slump block itself.  By the way, the Sentinel Slide still acts up from time to time.  In 1995, part of the old slide slipped, briefly blocking the river.  The road was flooded for a time until the Virgin, never to be denied for long, re-established its channel.

Stay tuned for more from Zion National Park!

Looking down-canyon at sunset from atop Sand Bench, which is the huge slump block of the Sentinel Slide.

Looking down-canyon at sunset from atop Sand Bench, which is the huge slump block of the Sentinel Slide.  I’m on top of one of the huge blocks moved by the slide.

 

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