Tuesday, March 23, 2010

A Geologic and Archaeologic Hike Into Arizona's Superstition Wilderness

This winter has been quite snowy and icy in Flagstaff. I'm really tired of it. So in mid-March I met up with a six friends in the Valley of the Sun with the intention of backpacking into the Superstition Mountains Wilderness Area. The "Sups" are one of my favorite desert hiking areas as I used to lead Ventures trips for the Museum of Northern Arizona here in the 1990's. This trip began at the Tortilla Trailhead on the north side of the range. We had big plans for a loop hike but the extreme runoff in all of the streams prevented us from from doing a hike down Fish Creek. So we backtracked after hiking into Angel Basin. Have a look at some of my photo's.

Norm leads the way with George, Bryan, Frank, and Bill following. Note the snow on the Four Peaks in the far background and the horizontal ash flow deposit in the middle ground.

Our first nights camp was made along the J F Trail about 4 miles in. We had a good view to the east across Goat Canyon towards White Mountain. Reavis Ranch is located on the other side of this high ridge. I honor all of the old timers who called this wilderness home for so many years. They knew its secrets well and were lucky to have lived life in this special place.

A self portrait at our first night's camp with the Four Peaks in the background. Arizona's Salt River flows from right to left in front of the Four Peaks but is out of view here.

Sunrise shot across the Sups and the Four Peaks in the Mazatzal Mountains. The Four Peaks are composed of Precambrian igneous and metamorphic rocks.

Nothing is better than sitting around the campfire with friends in a beautiful wilderness area

Angel Basin is a spectacular area that is traversed by Roger's Creek. Normally dry, the creek this year was a rushing torrent and John and I actually went swimming in the creek. I interpreted the rocks seen here as being part of a vent complex in the Superstition Mountain volcanic field. These rocks had dominant vertical orientations and the many dikes that we crossed along the way here were all oriented towards this center.

More spectacular vertical orientations to the rocks near our camp

In a nearby alcove is the Roger's Canyon ruin, a Salado culture habitation site that was formally excavated in the 1920's and 1941. Although build well within an overhanging alcove, the ruin still had an enclosed roof from 700 years ago.

Salado-age finger smears in the mud matrix of the walls of the ruin

Inside the ruin, I used my flash to get a view of the intricate construction techniques used by the Salado builders between 1350 and 1425

The view from the ruin upstream in Roger's Canyon. I have hiked down this stretch of canyon many times on previous trips. Note the shadowed wall on the right. These rocks are part of the vertical vent material that was part of the volcanic caldera. Note the horizontal ash flows illuminated in the sunlight in the center and left sides of the photo. These flows most likely made up the eastern slope of this 22 to 20 million year old volcano. It looks like the Roger's Creek drainage took advantage of the contact between these two deposits to establish its course.

A pool of clear water in Roger's Creek. Curiously, three streams converge in Angel Basin making me wonder if a previous caldera basin might have attracted water flowing downhill?

Sub-horizontal ash flow deposits observed to the north of Angel Basin

Vertically oriented vent deposits to the south of Angel Basin

On the way back out we camped along an unnamed stream that poured over a resistant dike. The J F. Trail from the Tortilla windmill seemed to take advantage of a resistant ridge of rock that was "held up" by a series of these dikes. I wonder if the cowboys of old knew that?

Our intrepid crew, left to right below, John Shortridge, George Abbott, and Frank Romaglia. Back row left to right, Wayne Ranney, Norm Henderson, Bryan Brown, and Bill Leibfried. We do these backpacks at least once a year besides running rivers all over thew southwest. It is nice to have such a great group of outdoor enthusiasts to partake in these trips.

1 comment:

Brian F. Gootee said...

Excellent trip Wayne and narrations! Wish I could have been there. I can say that these photos are inspiring enough for Rachel and I to fill that gap of the Sups we haven't done. Thanks for sharing!