I've been on a lot of trips lately and haven't had time to blog. But that will change this week. Here is a post about a northern Arizona landform that I have had my eye on for over 40 years. I finally made it!
Shinumo Altar from the east — the destination of our hike. It is located to the east of Marble Canyon and west of the Echo Cliffs.
Google Earth view of the region surrounding Shinumo Altar. The feature can be seen far and wide when on the ground.
Closer view showing our route around the top of the landform. The Eminence fault trends northeast between Shinumo Altar and a bit of Marble Canyon (upper left).
Oblique view to the northwest with Marble Canyon in the upper left. The mesa is capped and "held up" by the Shinarump Conglomerate, the basal member of the Chinle Formation. The Moenkopi Formation girdles the mesa top and can be seen here as the gray "apron" around the landform. The Kaibab Limestone makes up the foundation of Shinumo Altar and is obviously dissected by streams that lead to Marble Canyon.
The start of the hike was easy to determine — walk up the small drainage toward the red rocks.
We did not expect to find much in the way of prehistoric artifacts but were pleasantly surprised to first see this ground-stone boulder. Some of us suspected this might be Archaic in age where the people were grinding wild seed rather than domesticated crops.
Not too far from the ground-stone site, we came across a badly weathered granary. The wall rocks here were actually decaying in place rather than falling over. The cement was failing in the sandstone.
Moving uphill toward the top of the mesa, we saw fallen boulders of the Shinarump Conglomerate, with red beds of the Moenkopi Formation poking through.
Once on the top (about 700 feet above the Marble Platform) we could look west and see deep into the eastern wall of the Grand Canyon.
The highest elevation on Shinumo Altar is 6,520 feet. There were no trees but the Mormon tea (Ephedra sp.) was quite robust. I joked to my fellow hikers, "At what elevation does the Mormon tea turn to Juniper?"
An eastern view toward the Echo Cliffs.
Across the mesa top toward the Kaibab Plateau and uplift.
The clouds were fabulous and I'm starting to realize that high cirrus may be surpassing cumulonimbus-nimbus as my favorite cloud form.
A view directly north shows where the Echo Cliffs (right) seem to merge and intersect the Vermilion Cliffs (left). The Colorado River splits the two however and flows toward but to the left of the photograph within Marble Canyon. The river itself is responsible for the segregation of the two cliff lines.
Scott looking into the dissected drainage of Shinumo Wash.
Sandstone within the Shinarump Conglomerate frames a northwest view to Marble Canyon and the edge of the Kaibab Plateau/uplift.
My wonderful hiking companions, shown here, were Tony, Scott, and Tom. The conversation was excellent!
A gravel-rich desert pavement formed from loosened clasts of the Shinarump Conglomerate on top of the mesa. The Shinarump represents the first coarse-grained deposits that were shed northward during the Late Triassic, about 225 million years ago. The source area for this conglomerate was being uplifted in the initial westward drift of North America away from the supercontinent of Pangaea. Thus, the Shinarump is the bell-weather deposit signaling the beginning of an active margin in western North America. A few maps of Shinarump time may help visualize the setting.
The breakup of Pangaea initiated mountain building in southern Arizona, which shed sediment to the north as the Shinarump Conglomerate. The small red dot shows the location of Shinumo Altar in this setting. However, I have also placed its current latitude on this map (top yellow line). (Map from "Ancient Landscapes of Western North America" by Ron Blakey and Wayne Ranney, 2018.)
A closer view of the Shinarump depositional basin and fluvial system. The yellow dot is the location of Shinumo Altar. (Map from "Ancient Landscapes of the Colorado Plateau" by Ron Blakey and Wayne Ranney, 2008.)
Within the Shinarump fluvial system, large trees were kicked down in floods and quickly buried. They are now part of the rich petrified log heritage of this deposit and I found a nice specimen on the edge of the mesa.
Toward Marble Canyon from the northern point of Shinumo Altar.
Tom, Scott, and Tony at the large cairn on top of the mesa.
Tony and I are tea drinkers and we each brought a Thermos-full of black tea on the hike. The temperature hovered right at freezing all day but the sunshine and physical activity made it seem warmer. Still it was chilly up there.
A photo of Shinumo Altar at the end of our hike was a wonderful reward. It has been a lifetime goal of mine to visit this prominent landform. I'll never look at it the same way again!
This past weekend I went hiking in a new regional park near the city of Buckeye, Arizona. You can see the web page for the park here. This is the southern edge of the White Tank Mountains, one of the many metamorphic core complexes in the state. The Salt River Valley has received 5 inches of rain in the last month and so the saguaro's are fat, the ocotillo's are green and the desert is alive! No captions this time - just enjoy the warm desert view. As you look at the map below, the photos were taken on the Turnbuckle Trail, with the color green on the map.
This may have been the most scenic section of a trip full of scenic drives. I'll let the reader decide.
Map of Morocco showing our course to the west-southwest between the Anti-Atlas on the south and the High Atlas Mountains to the north. Destination Ouarzazate.
Leaving Erfoud, we encountered numerous man-made mounds along the roadside. These are access shafts to an underground irrigation system called a ketthara in Morocco (kanat in some other Arab countries). These mounds mark where vertical shafts have been dug to intersect a shallow and sloping water table. The system has been in use since about 1000 BCE Before Common Era) and was devised originally in Persia. The wells here are now abandoned having been affected by over-pumping when tourist infrastructure caused too many wells to be drilled, thus lowering the water table.
We were admiring the ketthara and taking pictures when a man appeared, seemingly out of nowhere in the desert, with jewelry to sell.
Some in our group were interested in this unexpected appearance and the man did quite well from our 20 minute stop.
In the Anti-Atlas, this interesting unconformity was seen, with flat-lying (and relatively young) sedimentary rocks overlying deformed early Paleozoic sediments. This outcrop is along R702 highway west out of Erfoud.
This is a view of a small fossil quarry on the flank of the Anti-Atlas. The small roads cut across the bedding planes in the tilted rocks but the wider areas are where mining occurred along the bedding planes. Much larger quarries are more industrialized and those shown here are likely from the earliest phases of fossil quarrying.
The normally dry wadis were full of run-off from the recent rains. This large wadi was issuing from the Anti-Atlas in the background.
Water running across the highway is a rare enough event that locals in this village came out just to watch vehicles drive through it.
The following six photographs were taken from the coach as we drove through small villages on our way to Ouarzazate. I share them with you to show normal everyday scenes in the hinterland of Morocco's Sahara country. I normally do not even attempt to take photos from a moving coach. However, the scenes we passed were so compelling that I gave it a try and it didn't turn out too bad. A preferred kind of "drive-by shooting."
This may be the village of Touroug.
Woman carrying the mornings harvest.
Goat herder watching the coach go by.
Small, tilted mountain range in the distance.
Folded sedimentary rocks of the Anti-Atlas. These beds of limestone have been put at an angle but within that angle, they are planar. When streams carve depressions in tilted planes, the "curvy" pattern develops. I've not had too much luck in trying to explain the origin of this interesting pattern in the rocks but one way I try is to have people imagine different colored "layers" of construction paper. If you look at that stack from the side and tilt the stack, you'll see different colored layers. But if you cut a curved, V-shaped piece out of the stack you would see each individual color appear as a swirl. So I ask you dear reader, "Help me explain this!"
There are many police stops on the roads in Morocco. They check if drivers licenses and vehicle registrations are current, and if the vehicles are safe. To many Americans, these can make it seem as if it a place is a police state. Actually, scenes like these are commonly seen in many of my world travels. The tourist coaches were always waved right on through.
The next set of photos are from near the town of Tenehir. We are now on Highway N10. The scenery was fantastic here.
Looking southeast over the oasis toward the southern face of the Atlas Mountains.
In many Moroccan villages, the old adobe heart is being abandoned for newer, cinder-block homes. The older town centers are left as ruins. Note the fruit-filled date palm on the left.
Another view of Tenehir in the passing clouds.
What a day! Puffy clouds, blue sky, an uplifted mountain front, a well watered and lush valley, and an adobe village in exotic Morocco.
The local vendors at the viewpoint obviously have experience letting their camel stick its head inside of coaches.
A close-up of the wadi wall reveals an obvious angular unconformity where more recent, uncemented gravel from the mountains overlies deformed and tilted red sediments.
This was definitely a southwestern-equivalent landscape!
The red sediment forming the partially covered apron in the distant mesa is likely Triassic-age deposits laid down as Africa began its eastward drift away from North America, around 220 million years ago. The red sediment collected in the growing rift. The mesa is capped by white limestone that signals incursion of the nascent Atlantic Ocean by about 205 million years ago. Later uplift of the Atlas range greatly deformed and partially eroded these sediments off of the mountains top.
Our destination in Tenehir was the Dades Gorges.
As we entered the gorge, it was evident that very large forces were at work to uplift the Atlas Mountains in the Alpine orogeny, the same mountain building event that created the Alps in southern Europe.
The Dades River has carved a 1,000-foot deep gorge in the Jurassic limestone. The walls shows evidence of faulting where blocks of crust had been jostled about in the uplift.
Once out of the gorge, we continued west along the base of the mountains and the Dades River valley. In the distance lies the Triassic and Jurassic couplet of rocks that formed broad colorful mesas.
This is the town of Boumaine Dades along the river of the same name.
At a rest stop along the way, there was a rock formation with a trail leading to the top. Young people came up here to drinks Cokes and flirt. There is never alcohol involved in public gatherings in Morocco - all of the street side cafes are where men go to drink tea and coffee. The highway followed an obvious deposit of conglomerate laid down by the Dades River. It has since been dissected and rests now about 100 feet above the valley floor. These are blocks of the conglomerate that have broken away from the main pedestal. The age of the conglomerate is likely Miocene or Pliocene, or about 15 to 5 million years old.
Fabrics for sale hanging on a wall.
Highway art - old tires have been cut into shapes resembling tea pots and colorfully painted.
The next four photos are a series of skyscapes seen along the drive near Talat.
Scenes like this just welcome the traveler to stand in awe.
The clouds slowly became thicker though the afternoon...
...until they dominated the sky.
Great light captured by the passing clouds.
This building is a kasbah, which is an Arabic word for fortress. Many kasbahs have been abandoned now and are in ruins along this stretch of highway. But a few have been restored to their former glory. This area is sometimes referred to as the road of a thousand kasbahs. This particular one is called Amerhidil.
Our group interacted with some local boys while making the stop. Our local guide, Seddik is on the right and could interpret for our group.
Handing out school supplies was something that brought our two groups together and a smile to the faces of the locals.
The highway continued to follow the conglomerate deposit, which was underlain by sediments that appeared to be valley fill, when the Dades River became blocked downstream from here.
Eventually, the river cut down down significantly into these sand, clay and mud deposits.
Just before entering Ouarzazate, we passed one of the world's largest solar energy projects, Masen (Moroccan Agency for Sustainable Energy). Morocco presently gets 97% of its energy needs from fossil fuels but has a goal of getting 52% from renewables by 2030. As I said at the start of this posting, this was a red-letter day for scenery!
So far our trip had focused on the rich cultural heritage of Morocco as we visited Rabat and Fes. By far ,most visitors come to this enchanted country for this reason. But I was here for a slightly different reward, having heard and known about the mountains and deserts for which the country is equally famous for. The drive today (September 27) was especially enticing for me.
Map of Morocco showing the route from Fes to Erfoud at the edge of the Sahara Desert. The map is labeled in French such that Moyen Atlas stands for the Middle Atlas Mountains and Haut Atlas means High Atlas Mountains. Note that Fes is located in a valley where the Middle Atlas begins.
For about 30 miles, the highway slowly climbs through rich agricultural lands of olives and grapes.
The village of Azrou is located at 4,100 feet in elevation and is constructed in a Swiss chalet style. It attracts snow in the winter and there is a ski area nearby.
Further along is a place where the Barbary Macaque (Macaque silvanus) can be observed at close range.
They are quite playful and I could watch primates for hours and not be bored.
Soon we climbed into the Azrou volcanic field, with basalt volcanoes and flows about 3 million to 600,000 years old.
Basalt and scoria cone.
This was a specular day for clouds and huge thunderstorms had rocked the western Sahara and the Atlas Mountains.
The highway followed this lava flow uphill for about 18 miles. The relative age of the flow can be known by noting the small arroyo cut into the top of the flow. In the distance, limestone bedrock protrudes above the younger flow.
Country scene along Morocco highway N13 in the Middle Atlas Mountains.
The highway climbed to over 7,000 feet through cedar, oak and pine forests. Large dead trees have been affected by recent years of drought in Morocco. These large trees are Atlas or Atlantic cedars (Cedrus atlantica), closely related to the Lebanon cedar.
It was a bit disheartening to see this logging truck as we whizzed by in the bus. We had heard that the Atlas cedar trees are now protected. Perhaps these lumberjacks are merely cutting the dead trees, which are thought to be dying due to the long-term drought in Morocco. See this article about their current status.
A last look at the majestic Atlas cedar before descending into the Sahara.
As we descended into the Moulouya River valley, near Midelt sedimentary rocks began to dominate the landscape. These still flat-lying sediments attest to their relative youthfulness, having been deposited in the river valley in the Cenozoic Era.
Looking back to the west as we climbed out of the Moulouya River valley. Note the giant cumulonimbus clouds forming in the early afternoon over the mountains. Lightning was seen at night within these clouds.
A woman along the highway near Air Ba Lahsene pushes her donkey with its load toward home.
Near Air Ba Lahsene. Note how runoff from above creates evenly spaced rills in the hill slope...
...with the material removed from within the rills coming to rest at the base of the slope in broad alluvial fans.
To the south the highly deformed sedimentary rocks were spectacular in the late afternoon sun! I was so jazzed to see this. The view shows the result of uplift during the Cretaceous time period.
More spectacular folding of the strata along the Ziz River (lower part of the photo).
Entering the Ziz River Canyon in this downstream view.
This is an upstream view after entering the canyon. The rocks are Jurassic age limestone. This scenery really floated my boat!
The canyon reminded me very much of the San Juan River canyon in Utah, although this particular one was a bit wider and not as deep.
Exiting the canyon near Errichidia, I noticed a bed of hummocky limestone in the cliff.
This close-up view reveals a Jurassic-age coral or algal reef system. The reefs would grow vertically in the shallow sea. Eventually, limestone deposits would drape over the reef structure (where the dark cave entrance is located). This was a fantastic sighting in the cliff wall. Morocco is a geologists paradise.
Overturned beds in the limestone near Errichidia. Merely driving by, it was hard to determine which limb was right-side-up and which was overturned.
Near Air Menzou.
Beautiful sky at the Hassan Ak-Dakhil reservoir on the Ziz River near Errichidia.
Later in the day, The clouds grew thicker with rays of sunlight filtering through.
The Ziz oasis below Errichidia. The majority of greenery in the valley bottom are date palms and olive trees.
Sunset from the Ziz oasis. What a drive we enjoyed! Spectacular views and great weather. The rains had cleared the skies. Next up - the Sahara.
Check out the graphics within this Washington Post story from September 12, 2018. The video that shows the birth of Hurricane Florence off the western Sahara Desert is amazing! Note that two other systems follow Florence - Issac and Helene. Their ultimate destinations are as yet unknown but a triple whammy is not out of the question.
PS - For some reason, the video loop that shows the track of Hurricane Florence across the whole Atlantic within this article is not displaying in the link provided. Hope you can see it though when you click on the link.
On a trip like this, I usually take hundreds and hundreds of photos and going through them afterwards i both rewarding and time-consuming. Most often I choose only photos that are well composed and exposed to include in a blog posting. However, other times I want to express a particular thought or emotion from the trip. In this posting, there isa combination of the two. And I sometimes question why I lug around 8 pounds of camera gear repeatedly to the same place. To which a ready answer does to mind - it is never the same! Time of day, time of year, time of life. It's always different.
I just love boiling mud pots! Maybe it is the boy in me wanting to get dirty. Here at Namafjall, the Icelandic rift creates near surface geothermal heat that boils groundwater, which in turn chemically weathers the silica rock below. The result is silica and clay mud mixed with boiling water.
The gurgling and plop of the mud creates an another world feeling in the observer. Plus the smell of the Earth's interior! Our local guide warned us of the rotten egg smell, to which I added, some overcooked hard-boiled eggs have the same smell of the interior of the earth - breathe deep and enjoy its exotic nature! Okay, I go overboard sometimes. But no need to hate it off the bat without first giving it a chance to thrill the soul.
You have to take a lot of pictures to get the four boils going up at once.
A steam vent adds a sense of motion to the scene.
Up close the steam is hot to the touch. Ones skin could not take more than two seconds exposed to its heat and speed. It hisses loudly as the steam escapes.
Note the yellow sulphur deposits that precipitate near the vent.
Next stop was Dimmuborgir near the shores of Lake Myvatn. Dimmu (dark) borgir (cities of castles) literally means the dark castles. It is a fantastic area that never ceases to amaze. But the geologic story is the true champion here. About 2,300 years ago (i.e. not that long ago but before people lived in Iceland) a lava flow came to rest on top of a shallow basin that held marsh, water forming a large lava lake about 30-40 feet deep. The top of the lava pool cooled forming a rocky crust. But on the inside, red hot lava was still heating the marshy ground below until steam began to shoot upwards through the hot lava. The vertical steam vents caused nearby portions of the lava lake to cool more quickly. Without warning, the lava drained away, collapsing the roof and leaving the steam vents standing like dark castles. An amazing place and story to go with it.
I had never noticed it before this trip but we saw a vertical stem vent in the middle of one of the castles. It is just below the rounded pinnacle on the right and trends downward into the top of the trees.
Numerous windows are carved into the castles as well.
Leaving Lake Myvatn, we passed Godafoss, another impressive Icelandic waterfall.
The parking area has been recently upgraded here. Note the small lava tube across the way.
Zooming into the wall near the lava tube across the way ( I have a 300 mm lens), I spied a very interesting set of textures. You will note two different textures are present - an upper regular set of vertically oriented columns, and a lower irregular oriented set of columns. The upper textures form what is called the colonnade and the lower part is called the entablature. The colonnade textures form in the absence of water while the entablature textures form when water interacts with the cooling lava. But I never before noticed where a colonnade rests on top of the entablature.
An even closer view reveals a possible explanation. Note the way the entablature fractures seem to emanate from a central fracture. I presumed that when this lava flow came to rest here, that it did so on top of wet ground. As the lava heated the water below, it formed steam which rose upwards. The steam channel started the cooling process - the fractures always form perpendicular to the cooling surface. It looks like the steam eventually was used up, allowing a colonnade to form on top. I'm telling you, stay here long enough and many insights begin to develop. It is a natural laboratory for earth processes!
On the road in the afternoon sun near Akureyri along the east side of Eyjafjörđur (Island Fjord). This is one of my favorite drives in Iceland as the sun always seems to be not far away.
Leaving Akureryi and driving up into the mountains.
In Iceland in the summer, one sees many of these plastic wrapped bales of hay for winter silage. The bales are wrapped in different colors.
This is the Öxandalur Valley, birthplace of the famous Icelandic poet Jonas Hallgrimsson. Actually "dalur" means valley in Icelandic (dalur equals "dale" in English) so it is redundant. Note the sharp mountain peak in the background.
This is Hraundrangi. It is an iconic mountain in Iceland but is usually in cloud. This was the best view I ever had of it. A quick glance might suggest that the peak formed as a cirque from glacial times. However, a wider view shows evidence for a catastrophic landslide here since the end of the Ice Age and what we are seeing the photo here is the headwall of the landslide.
Here is the rubble field to the south of Hraundrangi. Wow! What a difference the sun can make.
Although not native to Iceland, these daisy's were a welcome sight!
We spent the night in place not known for tourists - Sauđárkrókur. It is located along the Skagafjordur. This view is to the north toward the Arctic Circle.
The black sand beach at Sauđárkrókur.
Another location where we saw the debris field of a gigantic, post-glacial landslide. On the 8th of July this year, a very large landslide occurred in Iceland. Check out the AGU web site here for some incredible photos. These are still a very real thing in Iceland. I found a seven minute video that shows drone footage of this slide here. There may be a short ad to watch in Icelandic but you'll see the command in the lower right to skip after a few seconds. Wow!
What a day! August 11, 2018.
I had never before seen Eíriksjökull - it always so gray and cloudy in this part of Iceland. But look at this view.
Next was a visit to Grábrók, found right along the Ring Road. After making the short climb to top of Grábrók (on a constructed trail), we could see one of the other two nearby volcanoes, Grábrókarfell.
Birch twigs were recovered from inside the flows here in the early 2000s and they revealed a radiocarbon age of about 1,800 years ago - still about 670 years too early for people to have witnessed these erupting.
This is where a lava flow emanated to the surface from inside the cinder cone. Note the extent of the flow in the right distance - evident from the lighter-colored moss covering it. The trail to the top takes advantage of this lava flow, switchbacking up its spine.
Another amazing stop along the way is Hraunfossar (literally, Lava Falls). Hundreds of springs flow to the surface here into the Hvítá River, made blue from glacial flour (ice-pulverized rock).
Note how the springs all come from the same horizon. About 2,000 years ago a very porous aa lava flow covered an older, more dense flow below. The pre space in the upper flow acts as a conduit for Hvítá River water from farther upstream, where the river flows up against the young lava flow. The upper flow becomes saturated with water, creating the falls. The falls erupt here because the upper flow is nearing its distal end and the water is forced out.
Iceland is a land of tunnels! Tunnels under basalt ridges, mountain, fjords. Yes fjords. This tunnel, the Hvalfjörđur Tunnel, is almost 4 miles long and is about 540 feet below sea at its deepest point. The minimum amount of rock covering is 130 feet.
I had never before noticed so many landslides in Iceland. Perhaps it was the clear weather (likely). Or perhaps it tis my growing awareness of their ubiquity upon earth's landscapes (definitely). This may or may not be a landslide scar - it is very close to the sea and so may be a place where waves once washed against and eroded the cliff. Isostatic rebound has now caused the beach terrace to rise about 30 feet above the old seabed.
Gerðuberg on the Snæfellsnes Peninsula is a favorite stop.
Recent cinder cone formation left this impressive cone and flow to the east of it.
Note how the waterfalls just seem to appear our of nowhere in this view. The lighter-colored slopes are from mosses growing on quite recent lava flows. Like at Hraunfossar above, this flows were porous and act like sponges for water. When they encounter more dense flows below, the water is forced out suddenly. One can imagine how ancestral peoples would be baffled by such "magic." It doesn't take much more to understand the roots of some of our ancestral beliefs.
Iceland is a land of waterfalls, basalt lava, sea cliffs, and nature. I highly recommend a visit - just do not expect great weather at any time of year. For the geologist, it is a 'must see' place.
The old church at Buđir. Thank yo has always for reading!