Fascinating courtly intrigue and bloody power games set on a generation ship full of secrets―Medusa Uploaded is an imaginative, intense mystery about family dramas and ancient technologies whose influence reverberates across the stars. Disturbing, exciting, and frankly kind of mind-blowing.” ―Annalee Newitz, author of Autonomous

Showing posts with label Arizona geology. Show all posts
Showing posts with label Arizona geology. Show all posts

Tuesday, December 30, 2014

Third Honeymoon's A Charm



A trip to Sedona to celebrate our 25th wedding anniversary seemed like the perfect time to review hikes and burger joints from Roger Naylor's new book, Boots & Burgers: An Arizona Handbook for Hungry Hikers, so I marked a few hikes and Google-mapped a couple of restaurants, and we set out on a Wednesday evening.  Thursday morning we rose with every intention of doing the Hiline Trail (after a hardy breakfast at Coffee Pot Restaurant). But to get to the trailhead, you have to drive up a rugged section of Schnebly Hill Road, and that's when we ran into a snag.

Our little Toyota truck probably could have navigated that road, but I wasn't 100% per cent sure, and the warranty on our tires is expired. So after a brief foray about 20 feet in, where we immediately began to wallow, I turned the truck around and parked it in the paved lot next to Marg's Draw. That trail was tempting, but being unable to drive up Schnebly Hill made me feel very curious about the road, itself.


Schnebly Hill is a very old trail. Martha Summerhayes and her party used it to get to Sedona in the 1870s (Vanished Arizona). I wondered if it would make a good hiking trail in its own right. So Ernie and I decided to hike up the road to the trail head (we figured it was about 2.5 miles), and then we would decide if we could slog any further up the Hiline Trail, or if we should just turn around and hike back. Our other option was to hike Marg's Draw, which looked very alluring from the trailhead. We decided to do that one the next time we return to Sedona, and set off up good ol' Schnebly Hill.

I'm glad we did, because I learned a few things I hadn't known before. For one thing, I realized I'd like to buy a two-seater ATV some day. Several of them passed us on the way, and I admired the way they navigated the rugged rocks and soft sand/silt that challenge any kind of wheels on that road. I also saw something I hadn't seen before.


If you've read Wayne Ranney's book, Sedona Through Time, you know about the Hickey Formation and the Plateau Basalts – but those layers have eroded away in the Sedona area, and it's hard to tell where they were. You see basalt rocks and boulders along Oak Creek (some of them gigantic), but I hadn't seen them along the HWY 179 trails until I spotted them poking up out of the middle of Schnebly Hill Road. I have no idea just how large those rocks are, since they're almost completely buried by sand and silt from the Hermit Shale and Schnebly Hill Formations – for all I know, they may be as big as houses.

There was a wash alongside the road with some standing water in pools and the sort of slickrock you can find at Slide Rock State Park, Bell Rock, Red Rock State Park, etc. Recent running water had left beautiful ripples in the fine sand/silt. We were careful not to stick our gallumphy footprints in it. Overhead, on all sides, red rock formations stared down at us. We made it all the way up to the trail head – but decided to hike back down again, since our day was turning toward afternoon. Four to five hours hiking is plenty for me.


So down we went again. We didn't accomplish my goal of hiking either of those trails (this time around), but we succeeded at the burger end of things beyond my wildest dreams. For our honeymoon supper, we visited Cowboy Club in uptown Sedona. We both ordered the Cowboy Up burger, which is adorned with bacon, cheddar cheese, crispy onions, and BBQ sauce. The burger is ground sirloin, and we asked for ours to be cooked well-done, yet they were still juicy and tasty. They were served on a buttery pretzel roll (just as Roger described it). From the way the burger was described, I thought it might be a bit sloppy, but the ratio of toppings to meat and bun was just right. I had the sweet potato fries with mine, and my husband had the beans. We didn't need appetizers or desert, because the combo was quite filling.

Friday, on our drive back to Phoenix, we decided to take the scenic route and go south on HWY 89A, through Cottonwood, Jerome, and Prescott. This is one of the most beautiful drives you can do in AZ. It's interesting if you're driving south to north, but I particularly enjoy it in the other direction, climbing into Jerome instead of descending through it. If you're the driver, you will have to remind yourself to watch the road, because it twists and turns while continually revealing breathtaking scenery.


By the time we reached Prescott, I was ready to try another burger joint from Roger's book, Bill's Grill. It doesn't seem to be on the main drag through town, but it actually is. It's an innocuous little place on a stretch of the highway at the southern end of town. Hwy 89 is called South Montezuma Street for that stretch, so don't let it throw you.

We chose to sit in the enclosed porch, mostly because we didn't realize it was a porch, it was so cozy and well-protected from the elements. This proved important, because on that particular day a storm was passing through Arizona, bringing colder temps and lots of wind and rain. We felt snug and comfy as we ordered the Southwest BBQ Burger (I just can't resist the bacon). It doesn't come with a side – you have to order that extra, but you may find you don't need it. The burger is pretty big, and I couldn't make much of a dent in the sweet potato fries I ordered (though they were perfect). It had a couple of things in common with the burger I got at Cowboy Club. One was that it also was not overwhelmed by its condiments. And the other was that they use locally raised beef. These burgers were so tasty, I think I've been spoiled for life.

So there you have it – another foray into the hiking & burger heaven of Roger Naylor's new book. I am convinced. I shall continue my Naylor-guided explorations. Watch this space for further developments . . .



Thursday, November 13, 2014

It's Not the Lake, It's the Great Geology



I have to confess that I'm not a water sports fan, and I'm pretty sure that Lake Pleasant is a great place to get a sunburn. That said, I've noticed that a lot of locals really enjoy the lake and its recreational opportunities, so I'm not trying to knock it -- I simply don't know enough about that aspect of it to write a review about it. Instead, I'd like to talk about the geology and a wonderful trail we hiked.
The Hieroglyphic Mountains (and its neighbors) are a testament to the varied volcanic activity that shaped most of Arizona over the last 1.7 billion years, though most of the landscape you see on the Pipeline Trail near Lake Pleasant has its origins in the Tertiary and Quaternary periods. We saw everything from vesicular basalt to rhyolitic tuff, and the colors were fabulous. Check out the USGS pdf map of the area -- it will give you a more detailed breakdown of the rock types you'll find in the area.

The trail is not a loop, and it's 2.2 miles each way, but it's moderate in difficulty, without a lot of climbing. The views are gorgeous, especially if you're fond of desert flora and fauna, and there are even wild donkeys in the area (we saw several of them, and heard their "EE-Aw"s echoing up and down the canyon). This is a hike for the cool season, late Oct to late March, and you need to take water -- and your camera!

After hiking both ways on the trail, we drove to Wickenburg and had supper at Anita's Cocina, ignoring the fast food joints along HWY 60. It was a wonderful day.



Saturday, September 14, 2013

Friday, December 7, 2012

Wayne Ranney: Geologist, Adventurer, and Mapmaster Flash


You may recall that I mentioned, sometime in the recent past, the paleogeographic maps are fabulous. Or you may not. But they are. And what's even more wonderful is that Wayne Ranney, one of the guys behind those afore-mentioned fabulous maps will be speaking at the Heard Museum on Tuesday, December 11, at 1:30 p.m. To 3:00 p.m. He'll be signing copies of his books in our book store afterward. I've posted a review of the book he co-wrote with Ron Blakey, Ancient Landscapes of the Colorado Plateau, which features maps that depict what the Colorado Plateau may have looked like millions and even billions of years ago.


 I will soon be posting a review of Carving Grand Canyon: Evidence, Theories, and Mystery (2nd Edition) which casts light on past and recent arguments about when the Grand Canyon began to form.


 And I look forward to diving into Sedona Through Time, which delves into the formation of one of the most beautiful places on Earth: Oak Creek Canyon.


We have all three titles available at the Heard Museum Book Store, and Mr. Ranney will be signing there after his lecture. Don't miss it!

Wednesday, May 16, 2012

Into The Great Semi-Known




At mondoernesto, my husband, Ernie, wrote about our recent trip up North to Sunset Crater and Wupatki National Monument. This was one of those trips we needed to take to feed our souls. Money is tight right now, and these trips are much less frequent than they used to be. So we packed as much fun as we possibly could into one day, starting the trip at 6:00 a.m. and ending it at 8:00 p.m.

If I could, I would live on the road. Granted, I've never had to do that, and maybe you get sick of it pretty past. But in my opinion, you get a lot less sick of it if you can take your time (and if the money doesn't run out). After we got up in the wee hours and fed the hungry cannibals (both feline and canine), we got into our truck and hit the road. My heart was flying.


About an hour-and-a-half up I-17, off Exit 289, there's a turn-around that can take you in three different directions. If you go right, you'll get to Cliff Castle Casino. If you go straight forward(ish), you'll get to the cliff dwellings of Montezuma Castle. And if you go left, you'll end up at a combo gas station/fast food joint. I've come to love that odd little hybrid at the end of the left-hand turn. We always stop to get coffee there, get gas, and make a pit stop. It has come to symbolize the beginning of all journeys (or at least, the ones that go up I-17).

Montezuma Castle and Montezuma Well are both fascinating and beautiful destinations. A peacefulness pervades the scene in both places that leads visitors to assume an idyllic life for the people who actually lived there, which was probably true at least part of the time. Likewise, Walnut Canyon, which eroded out of the same top layers that compose the walls of the Grand Canyon, is also a happy destination. But we were bound for Sunset Crater and Wupatki, places where life could sometimes be less than idyllic.



For one thing, around 1045 AD, a volcano went off. It was a small one, a cinder cone, but on the human scale that's plenty big enough. Sunset Crater is part of the San Francisco Volcanic field – the San Francisco Peaks are what's left of a composite/stratovolcano that blew itself up pretty much the way geologists would expect a stratovolcano to blow – out one side, like Mount Saint Helen's or Vesuvius. But the mix of magma in that general area is a little more complicated than that. The stratovolcano squirted out mostly intermediate volcanic rocks and pyroclastic flows, but Sunset Crater started as a rift eruption, and its magma was the low-silica kind you might expect to see on Hawaii, from one of its shield volcanoes. This low-silica magma had a high gas content, so it created a curtain of fire, blowing the runny lava high into the air, where it got whipped into cinders.


The eruption eventually became concentrated at one end and built a cinder cone. Near the end of the eruption, two types of mafic (low silica-high Fe & Mg) lava flows burst through the cone at the bottom: runny pahoehoe lava and chunky Aa. And for the grand (semi-)finalé, The volcano blew more gassy, mafic lava into the air, out of the top, and rained cinders down on the landscape. (Those darker cinders, higher in Fe & Mg, are called scoria.)

I say semi-finalé, because apparently hot magma continued to rise underground for a while, and this stuff melted enough of the surrounding rocks to be higher in silica. When it oozed through cracks in lava that was already cool, it acted kind of like toothpaste. You can see examples of this squeeze-y stuff in one of the cracks near the Lava Flow trail head.


It's convenient to generalize about geological processes, partly to avoid confusing people and partly to paint a broader picture. But when you're actually confronted with the landforms in this part of Arizona, you have to admit there's a lot we don't know. The shallow subduction of the Farallon Plate near the end of the Mesozoic Era seems to have drawn volcanic activity farther inland than you would normally see it, which is why a stratovolcano ended up in Arizona. But something even more interesting may have happened. Arizona may have actually over-ridden the hot upwelling that was creating the rift in the first place.



If you look at the Atlantic Ridge System, you'll see it lies pretty much in the middle of that ocean. It's a classic opening basin. But the Pacific Ridge System in messier. The plates are moving apart at a faster rate, and most of the volcanic activity in the world is happening at the edges of those plates. Right in the middle of the Pacific Plate, a mantle plume is steadily blasting through, creating the Hawaiian island chain. Another plume created the Yellowstone Caldera. And if you look at New Mexico and Southern Colorado, you'll see that an ongoing continental rift has created the Rio Grande River Valley. The Colorado Plateau continues to rise. So geologists think we must be still moving over that hot, upwelling spot.



Since peridotite and basalt have been found in Arizona and New Mexico, some of that hot stuff has to have come from the mantle. These are the nerdy thoughts that run through my mind as Ernie and I hike all over the Sunset Crater and Wupatki trails. In Wupatki, people used the little box canyons to divert water to their gardens. And though there's a lot of talk these days about how hot and dry it is there, 1000 years ago there was probably more ground water, simply because there weren't any gigantic communities nearby draining it. The cinders that lie on top of the soil keep rainwater from running off – they filter down into the aquifer, and emerge as springs.


The stones used to build the dwellings were carved out of the Moenkopi formation, a wonderful mix of sandstone and shale that erodes into whimsical shapes.


As Ernie and I hiked through the sites, I noticed that the sacred mountains could be seen from all directions.  Any argument about why people settled in the area must include those mountains.  
The day was only half gone.  More adventures loomed on the horizon, like storm clouds . . .




COMING NEXT – OAK CREEK CANYON, VORTEX OF FABULOSITY