Mud Cracks

One of the most fascinating things about the desert is the prevalence of mud cracks. I remember hiking into the Pariah Canyon in Northern Arizona/Southern Utah and along the dry stream bed there were huge, dinner plate sized, mud cracks. They were so dry and hard that they clinked like glass and cracked loudly when we walked on them. When I was young, I used to take apart the mud cracks like puzzles and try to put them back together. Anytime a layer of clay silt is deposited by a rainstorm in a depression in the ground, when the clay dries it shrinks and forms the puzzle pattern mud cracks. 

Like everything else in the world, mud cracks are studied by geologists. If the mud cracks are subsequently covered by another layer of silt and preserved and then through geological changes hardened into rock, they give us a record of the long ago drying event. They use mud cracks to determine the orientation of the original sedimentary beds that formed the cracks. The edges of the mud cracks curl upward and point out which direction was up in the original bed. Also, the cracks get thinner as they go down into the layers and point downward. 

We had a recent thunderstorm in Mesa and the ditches on the sides of the canals filled with water. Of course, the water evaporates in a day (or even a few minutes or hours) but it leaves behind a thin sheet of sediment, dust from the canal road, that dries into the fabulous patterns of mud cracks. If you would like to see a number of different photos, go to the Earth Science World Image Bank. 

Mud cracks are like many things I find while walking Arizona, they are fascinating, interesting and mostly ignored by everyone.

Going nowhere and everywhere

As anyone who knows me well is well aware, I am a fan of Escher. Here is a really interesting 360.


Tribute to Escher in Barcelona

Arizona's Volcanic Fields

Arizona is not usually associated with volcanoes or with volcanic activity, but much of the state is dominated by former volcanoes and huge areas of lava flows and cinder cones. In north central Arizona, the San Francisco Volcanic Field is listed by the U.S.G.S. as a potentially active volcanic area. Near Flagstaff, Sunset Crater is likely Arizona's most recent volcanic cone, the eruption is generally dated to between 1040 and 1100 A.D. The area around the Crater is now a national monument and a surprisingly small one at that. The Visitors' Center, the campgrounds and most of the scenery lie outside of the national monument. The picture above shows a portion of the Bonita Lava Flow, located slightly north and mostly west of the main crater or cinder cone known as Sunset Crater.

The Monument is heavily visited because of its close proximity to Highway 89, a very busy route north and south in Arizona, and to the City of Flagstaff. The Monument is almost at the edge of the City Limits. In my experience the Bonita Campground, adjacent to the Monument itself, is almost always full or nearly full of campers the entire summer.

Historically, the National Park Service had a lot of interesting activities at the Monument, including hikes up to the top of Sunset Crater and tours of local ice caves, really lava tubes. Neither of these activities are allowed under the present management of the Monument. The NPS actually hauled huge amounts of cinders back to the cone to replace those worn down by the trails up the hill.

The Bonita Lava Flow is very interesting. As the lava flowed from the volcanic vents, the surface of the lava cooled. With the cooling, the surface was broken into plates that look similar to huge plates covering the entire lave field. The lava tubes formed when the walls of the tube cooled and solidified while liquid lava was still moving through the tube. When the liquid lava ran out of the tube, it left a long worm-like tunnel often referred to as a lava tube cave. There are several of these lava tube caves in Arizona, some of which are more than a mile in length.

Since you can drive through Sunset Crater National Monument in about half an hour, even at 35 mph, it is worth stopping, even if you don't have much time.

Smoke in the Canyon

According to the National Park Service, the Saffron Fire, currently burning in the Kaibab National Forest at the northern end of the Rainbow Plateau, 2 miles south of the park/forest boundary and 15 miles northwest of the North Rim. As of July 16, 2010, the fire had burned over 3,260 acres. The current fire plan is to allow the fire to burn naturally "within the planned management boundaries (north and east of the canyon rim, south of Forest Roads (FR) 268 and 223, and north of Swamp Ridge Road – the east/west section of the W4 road) in order to maintain fire’s natural role in the ecosystem." See NPS. 

During our recent trip to the North Rim, we found the smoke from the fire drifting generally to the east, pushed by the prevailing south by southwest winds. In approaching the Park we crossed a band of heavy smoke. At first, at the North Rim, the smoke was mainly to the north of the Grand Canyon National Park, but by the next day the smoke had filled the canyon to the east and south. The picture above shows the smoke looking east from the vicinity of Cape Royal. The bright spot is the reflection of the sun in my camera lens caused by the smoke. 

There is a lively controversy over the advisability of fire suppression in most instances. Years of unwise fire suppression have caused a huge build up of combustibles in the forests and when there is a fire, the fires burn very hot and kill all of the vegetation. Driving out to Cape Royal from the North Rim Visitors Center, you can see multiple fire burns in various stages of regrowth. The natural Ponderosa pine forest has an open meadow-like nature. Overgrowth of trees due mainly to fire suppression causes the forest to thicken unnaturally and become susceptible to dangerous fires and also bark beetles and disease. 

Flagstaff has recently suffered a huge fire with flames barely being stopped at the edge of subdivisions. The Schultz fire burned 15,075 acres north and east of Flagstaff. Misguided concerns about "preserving" the forest in the past have contributed to recent huge uncontrolled fires. In Flagstaff the Grand Canyon Forests Partnership is actively moving forward on a forest restoration project in the Fort Valley area northwest of Flagstaff. Treatments of the forest vary: thinning of trees, prescribed burning, meadow and wetland restoration, recreation management, etc. Through these means and with the involvement of the public, the Grand Canyon Forests Partnership hopes to enhance forest values so that they are healthy and sustainable for generations to come.

Death in the Grand Canyon

2009 saw a total of 12 tourists die as a result of visits to the Grand Canyon. However, to put this in perspective, about 4.5 million tourists visit the Canyon every year. Last year's victims included 10 visitors who died from accidents within the canyon, four on backcountry trails and one death from suicide and another from a heart attack. Observing the footwear and physical condition of a lot of the visitors, it is a miracle that more people don't die. I have seen people hiking down the train into the Canyon in flip-flops and even high heels. Most of the viewpoints on the Rim of the Canyon have extreme exposure, but I have seen tourists literally dancing on the edge of the cliffs, apparently unaware of the extreme heights.

One particularly tragic death came from heat exhaustion to a 20-year-old characterized as an "Eagle Scout." He was apparently on his way to find the famous Thunder River on the Canyon's North Rim. He died in mid-July when temperatures in the depths of the Canyon can exceed 100 degrees.

This year, July is also generating news articles about deaths in the Canyon. On July 8, 2010 Park Rangers recovered the body of a female hiker in the same general area where the man died last year, the Toroweap Valley. It is likely that these hikers vastly underestimate the distances, elevation changes and heat in the Canyon.

On one hike into the Canyon, we left the North Rim at 27 degrees and by the time we reached the Colorado River the temperature was 97 degrees. It is very difficult to drink enough water hiking in almost 100 degree temperatures to keep hydrated and maintain life. Many hiker try to avoid the heat by hiking at night or during the early morning hours.

Other deaths in the Canyon are more likely the result of the number of people visiting the Canyon. With such a large number of people, statistically, somebody is going to die from a heart attack or commit suicide. In May, June and July of 2010 there have been apparent suicides at the Canyon.

Happy Fourth of July

The Fourth of July in Phoenix is an ambivalent holiday. The State is relatively conservative but the Fourth comes in the middle of the summer. Virtually anyone that can leave town does so. When I was growing up, (some think I never did), we spent all summer up on the "mountain." Translated, into Arizona speak, we actually were out on the Plateau in St. Johns, where we could see mountains to the south. The temperatures were slightly less intense than the Valley and it did rain every couple of weeks. The Fourth of July was a huge holiday on the mountain, a cannon salute at 6:00 am, with races, pancake breakfast, patriotic speeches, barbeque in park, dances and parties. In Phoenix, it was mostly ignored. There was (and is) the obligatory fireworks display, but except for family gatherings, there isn't much going on. So that is why I have a picture of the Statue of Liberty.

Mesa has tried to buck the tradition by having a Main Street gathering, but like most things in Mesa, they have almost no publicity. So almost no one, relatively speaking, spends the evening on Main Street.

It is strange to me that this low key ignoring of the Fourth of July seems to contrast with the avowed patriotism of almost everyone. I guess when you match up patriotism with 110 degrees outside, the temperature wins. The local Boy Scout troop does put up flags in our neighborhood. But this is not done out of a sense of patriotism but as a fund raising activity. You donate a set amount to the Troop and they put a flag on your front lawn on every holiday, including Flag Day and the Fourth of July.

Saturday in the desert

We had an unusual day at home for a change. Since we both work all week and serve every Saturday at the Mesa, Arizona Temple, we seldom get a free day to do what we need to do around the house. When out subdivision was built, it was an grapefruit orchard and some of the old trees still grow in the yards. But time and re-plantings have changed the nature of the neighborhood and it doesn't look anything like an orchard. Some of the older trees are dying and being replaced from time to time. The first settlers in the Salt River Valley used the existing Indian canals rebuilt to water their crops. Eventually, the ditches and laterals were put underground. Some of the people in the neighborhood still water their yards with underground irrigation. The house we bought has a sprinkler system but the irrigation has been blocked off. Or, mostly blocked off. After living here for a while, we discovered that the old underground irrigation pipes are still there. We found them when holes opened up in flower beds and other locations that were essentially drains into the old pipes. 

So, this morning the first item of business was to block the most bothersome of the holes down to the old pipes so the sprinkler water wouldn't run down into the ground and disappear. That took just a few minutes but then the job began to expand to include enlarging the basins around the new citrus trees in back. We are used to having a huge variety of citrus and when we moved into this present house, we only had tangerines, oranges and grapefruit. So, one of the first items on the agenda when we moved in, was to plant more citrus, this time a navel orange and a tangelo. We have learned by observation, to buy the trees small and let them grow. A smaller tree will be more healthy and produce more fruit earlier than a large fully grown tree. It takes the larger tree a lot longer to get established and produce fruit.

Expanding the watering basins progressed to knocking down cobwebs and cutting a few bushes back. All this was happening as the temperature continued to climb to over 100 degrees. I put the pictures of the two saguaros at the beginning to remind you that I am writing from the middle of one of the hottest large cities in the world. We made a detour to the hardware store to get some screen to fix two torn window screens. Fixing the screens was done later in the day and we suffered mightily from the heat by that time. I have decided not to fix window screens for a profession. I imagine it would be easier to do if you had somewhere other than the floor to work on, but sitting on the floor and trying to get the screen straight is pretty sweaty work. I decided to take a break and watch the Prologue to the Tour de France. I got the program on just in time to see Lance Armstrong come in fourth. I doubt I will see much of the race since we seldom have time to watch anything on TV. This is the first time I remember them having all of this classic bicycle race on TV that we didn't have to pay extra to see.

It is always nice to get a few things done before the heat gets to you and you start to sit around and drink lemonade.