HIKING PICACHO PEAK

PICACHO PEAK (FAR LEFT).

I currently am camped at Picacho Peak State Park, north of Tucson about 30 miles, and south of Casa Grande about 20 miles.  It is one beauty of a place to spend some time if isolation is of interest.  Although the park is adjacent to Interstate 10, I can sit in my lawn chair and watch the sun go down over mountain ranges perhaps 40 miles away.  It seems that the only “things” between my chair and the mountains are hundreds of saguaro cacti.

Picacho Peak is sort of a misnomer since Picacho is a Spanish word for “big peak” so a translation would be big peak peak.  Whatever the case, it is a fantastic place to camp and hike.  The Park is in the Basin and Range Physiographic Province so most of the many mountain ranges that I see from my easy chair are horsts (uplifted blocks) separated by expansive grabens or half-grabens (down-dropped blocks).  The grabens are now large alluvial basins.  Periodically there are outcrops of volcanic rocks (see previous blog on Ragged Top).

The Park’s main attraction is Picacho Peak, a large chunk of basalt that has been tilted and faulted.  In fact, much of the basalt flow(s) is now hidden under the alluvial fill.  It is my understanding that the volcanics at the Park are about 22 Ma and represent the top plate of a large detachment fault (large normal fault) with the bottom plate being the Precambrian granite and gneiss east across the Interstate—the Picacho Mountains (Kresan, 1987).  I located several instances of old mining structures, mostly glory holes and simple excavations.  The miners evidently were after copper since most of the mines seem to follow greenish-blue stained rock; breccias associated with faults also were common targets. The detachment provided a conduit for hydrothermal fluids that charged the upper-plate rocks with mineralizing fluids that carried Zr and Ba, along with Au, Ag, and Cu, during detachment 17–18 Ma (Brooks, 1986).

As an avid hiker I decided to take my afternoon stroll to the top of Picacho Peak situated at 3374 feet with an elevation gain of approximately 1500 feet in 2.1 miles.  Little did I know that my walk would turn into “a really, really, hard hike”.  The first 900 feet of elevation gain was OK and got me to a saddle, and then I saw something on the other side that made my heart go pitter-patter a little faster.  I needed to go back down before going up again (always a bad sign) and the path down was between two cables, and steep, very steep!  That was only the beginning for the remainder of the hike was always in sight of cables with some climbs 70 degrees.  In another place I had to hold the cables and wiggle up a crack in the basalt—climbs like that are hard on an old guy.  And speaking of age, one of the high school kids sort of hiking with me (I was explaining geology—never miss a chance for that) asked, “Say, how old are you?  You hike pretty good for an old guy”.  The hike ended up about four hours in length with a net gain of 2366 (not 1500) feet in the 2.1 miles.  Old guys rock!

REFERENCES CITED

Brooks, W. E., 1986, Distribution of Anomalously High K₂O Volcanic Rocks in Arizona: Metasomatism at the Picacho Peak Detachment Fault: Geology, v. 14, no.4.

Kresan, P. L., 1987, Arizona Geology: An Aerial Tour: Arizona Bureau of Geology and Mineral Technology Fieldnotes, V. 17, No. 3.

mike

THE NEED TO WIGGLE UP A CRACK!

A FAIRLY STEEP SLIDE.

A NETWORK OF CABLES LEADING UP (AND DOWN).

MADE IT TO THE TOP. PICACHO MTNS. IN BACKGROUND.

A VIEW FROM THE EASY CHAIR.

RAGGED TOP: TERTIARY RHYOLITE

Ragged Top is an interesting mountain located in the Silver Bell Mountains west of Tucson, Arizona, and in the newly designated (Clinton Administration) Ironwood Forest National Monument,   The Silver Bells have complexly folded and faulted igneous, metamorphic, and sedimentary rocks that range in age from the Precambrian to Quaternary (Kreidler, 1987).  Ragged Top is a mass of Tertiary rhyolite that may represent a volcanic neck or a hypabyssal stock.  The peak gets its name from the massive erosion that has left behind spires and sharp-pointed peaks.  There is an elevation gain of about 1767 feet from the desert floor (2140 feet) to the summit (3907 feet) and the hiking trail (mostly just bushwhacking) is quite strenuous.  Ironwood Forest National Monument features plants of the Sonoran Desert, including the desert ironwood, a shrub-like tree that has beautiful purple flowers in the spring.  In addition, there are a number of Hohokam petroglyph sites in the Monument.  But I believe that the major scenic feature is the majestic Ragged Top.

REFERENCES CITED

Kreidler, T. J., 1987, Mineral Investigation of the Ragged Top Wilderness Study Area (AZ-020-197), Pima County, Arizona: U. S. Bureau of Mines  Mineral Land Assessment Open File Report 80-87.

mike

CSMS GROUPS ARE ACTIVE!

The Colorado Springs Mineralogical Society (CSMS) has a number of active subgroups that meet on a regular schedule.  Visitors and new members are always welcome.

Kerry Burroughs leads the Crystal Study Group whose members are dedicated to the discovery, identification and study of crystalline minerals of all types.  The Group specializes in the recovery and preparation of numerous local minerals for which the Pikes Peak region is world renown, especially Amazonite, Smokey Quartz, Topaz and Fluorite.  The Crystal Study Group meets every 4th Thursday at 7:00 PM in the Senior Center.  Additional information: info@csms.us

The Faceting Group, led by Paul Berry, meets in the Senior Center on the 4th Thursday at 7:00 PM.  The group has use of faceting machines housed in the Center and members turn out a variety of spectacular gem and semi-precious specimens. Additional information: info@csms.us

The Fossil Study Group organizes meetings around the interests of the members. Programs are scheduled, fossils identified, paleontological discussions held, and collecting techniques discussed. Members are encouraged to lead field trips to prospective collecting localities. In addition, each member brings to the meetings fossils for "Show and Tell".  Jack Null coordinates the “case” entered into the annual CSMS Show.  Although Mike Nelson is listed as leader, many other members offer presentations and identification skills.

Meetings are generally scheduled for the first Tuesday of the month at 7:00 PM at the Senior Center. However, the Group does not meet during June, July and August unless a field trip is scheduled.  It is best to contact Mike at www.csrockguy.yahoo with questions.

The following presentations are scheduled:

March 1 Presiding and presentation (Glen Eyrie fossils): Jack Null

April 5 Presiding and presentation: Jerry Suchan

May 3: Presentation (History of Florissant): Steven Veatch

The CSMS Micromount Group is interested in the collection and preparation of very small mineral specimens best viewed under a microscope.  The Group specializes in looking at tiny specimens of quite rare minerals, and displaying fantastic sprays of very delicate crystals that could not even exist on a larger scale.

The Micromounters, led by Phil McCollum, meets every 2nd Tuesday at the Senior Center.  Additional information: info@csms.us

The Lapidary Group meets on a regular/irregular schedule on the 1^st Saturday of the month, noon, at a member’s home; therefore, interested participants should contact info@csms.us for additional information.  The members learn to perfect the art of cutting and polishing minerals and then mounting the finished products into jewelry settings.  The most common products resulting from this work are the cabochons, either free form or standard.  Sharon Holte leads the Lapidary Group.

Whereas the Lapidary Group works with minerals, the Jewelry Group constructs or builds the settings.  Members become proficient in silver smithing, silver soldering, wire wrapping, and lost wax casting.  This group is led by Bill Arnson and meets on a regular/irregular schedule at noon on the 3^rd Saturday of the month.  It is always best to contact Bill at ritaarnson@msn.com

CSMS has two quite active youth groups, both led by Steven Veatch and his associates.  The Pebble Pups includes children of all ages and meets the third Thursday of the month, 6:10 to 7:15 PM at the Senior Center.  The Juniors, mostly of junior high age, meet the same evening, same location, 5:15 to 6:30 PM.  The study periods include lectures, explanations and hands-on laboratories; participants often receive actual specimens for their personal collections.  The leaders also sponsor some individuals via the internet so check with Steven Veatch at info@csms.us

CSMS and RMFMS Annual Show

On June 24-26, 2011, the Colorado Springs Mineralogical Society (CSMS) will celebrate its 75^th anniversary by hosting the Rocky Mountain Federation of Mineralogical Societies (RMFMS) Annual Show and Convention (70^th anniversary), the 48^th annual Pikes Peak Gem and Mineral Show, and the 3^rd annual Rock Fair at WMMI (Western Museum of Mining and Industry).  The Best Western Academy Hotel at 8110 N. Academy Blvd. will host the activities of the Federation and the indoor Pikes Peak Show.  The WMMI at 225 North Gate Blvd., Colorado Springs (across from the US Air Force Academy) will play host to the outdoor Rock Fair.  The two localities are very close to each other at the north end of Colorado Springs and are near Interstate 25.  The events are under the leadership of Show Chair Ron “Yam” Yaminokoski at yamofthewest@gmail.com.

The theme for the events is Colorado’s Mining Heritage and several speakers will have presentations at the Federation activities.  In addition, CSMS members will be presenting several talks throughout the period at the outdoor show (actually there are a few rooms inside for such activities as the talks).  The WMMI is a natural location for events associated with our mining heritage as the 27 acre museum includes both indoor displays and outdoor exhibits such as an operating stream shovel.  See the museum web site at: http://wmmi.org/home.

CSMS will utilize both the WMMI and the hotel to display submitted cases. The competitive cases will be displayed at the convention hotel where all judging will take place.  The non-competitive cases will be featured at the WMMI.  CSMS cases will be available for those making prior arrangements.

CSMS has strong programs with both Pebble Pups and Juniors so there will be numerous activities for children (of all ages).  Perhaps most interesting will be the gold panning area operated by the local Gold Prospectors of Colorado club.  Always a big hit, beginners may learn to “pan gold” and actually keep what they find! 

A vibrant Silent Auction will be running at WMMI and all proceeds will benefit our scholarship program (geology/earth science majors in a collegiate environment).  Numerous vendors at both localities will have a wide variety specimens and equipment for sale.  Pre-meeting field trips start June 19 while post-meeting trips conclude June 29 so plan accordingly.

This outstanding summer event promises to offer ‘something for everyone” and so CSMS invites participants to the great city of Colorado Springs where you will be able to observe Pikes Peak (14,115’) every day!  Check the Federation web site at www.rmfms.org for continuing details or contact the Show Chair (yamofthewest.yahoo.com).

mike

FACETED SPURS: SIGNS OF MOVEMENT

THE PATRIARCH, OR IS IT MATRIARCH?

Faceted spurs are common, fairly easy to recognize, landforms found along the flanks of mountains in the western U. S. where active, or recently active, faults are present.  As the mountain ranges are uplifted, streams cut into the rocks and flow toward master streams located in the down-dropped and adjacent valleys.  Ridges are formed between the mountain streams and usually slope gently toward the adjacent valleys.  However, if bounding faults are active, a fault scarp (cliff) forms along the edge of the mountains.  This scarp has the tendency to truncate the interfluve ridges (spurs) and create a triangular shaped “faceted spur”.  Along the west flank of the Catalina Mountains north of Tucson, Arizona, the bounding Pirate Fault has created numerous faceted spurs that are quite evident from Catalina State Park.  These triangular features seem common on outcrops of the Tertiary Wilderness Suite Granite.

In south central Colorado, the east side of the San Luis Valley is bounded by the Sangre de Cristo Fault along the western side of the Sangre de Cristo Range.  The northern part of the range, usually referred to as the Culebra Range, is separated from the adjacent San Luis Basin by the Crestone Section (a large normal fault = mountains “up” and basin “down”) of the master Sangre de Cristo Fault (Ruleman and Machete, 2007).  This fault extends from Poncha Pass, the northern-most boundary of the San Luis Basin, south to the Great Sand Dunes (McCalpin, 1982).  The deepest part of the basin seems to lie adjacent to the Crestone Section where there may be 30,000 feet of sediment (Garca and Kind, 1965). 

The Culebra Range and the adjacent Crestone Section Fault are characterized by a steep-walled mountain front with well-developed faceted spurs.  Many of the fault scarps are developed on very recent late Pleistocene and Holocene alluvial deposits.  (McCalpin, 1982, 1986).  This would indicate movement along the fault within the last 10,000 years.

REFERENCES CITED

McCalpin, J.P., 1982, Quaternary Geology and Neotectonics of the West Flank of the Northern Sangre de Cristo Mountains, South-central Colorado: Colorado School of Mines Quarterly, v. 77, no. 3.

McCalpin, J.P., 1986, Quaternary Tectonics of the Sangre de Cristo and Villa Grove Fault Zones, in Rogers, W.P. and Kirkham, R.M., eds., Contributions to Colorado Seismicity and Tectonics—A 1986 update: Colorado Geological Survey Special Publication 28.

 Ruleman, C. and M. N. Machette, 2007, An Overview of the Sangre de Cristo Fault System and New Insights to Interactions Between Quaternary Faults in the Northern Rio Grande Rift in Ruleman, C., M. N. Machette, M-M. Coates, and M. L. Johnson, eds., 2007 Rocky Mountain Section Friends of the Pleistocene Field Trip—Quaternary Geology of the San Luis Basin of Colorado and New Mexico, September 7–9, 2007: U. S. Geological Survey Open-File Report 2007-1193. 

mike

WEST FACE OF SANTA CATALINA MOUNTAINS.  THE PIRATE FAULT LIES UNDER THE SEDIMENT AS THE MOUNTAIN FRONT HAS RECEDED.  THE FACETED SPURS ARE GEOLOGICALLY OLDER (TERTIARY) THAN SIMILAR FEATURES ALONG THE SANGRE DE CRISTO MOUNTAINS.

WEST FACE OF THE SANGRE DE CRISTO MOUNTAINS AT NORTHERN END OF THE SAN LUIS VALLY.  MOVEMENT ALONG THE CRESTONE FAULT IS GEOLOGICALLY YOUNGER THAN THE PIRATE FAULT IN ARIZONA.

GOOGLE EARTH IMAGE OF SANTA CATALINA MOUNTAINS AND ADJACENT FEATURES.

GOOGLE EARTH IMAGE SHOWING EXTREME NORTHERN END OF SAN LUIS BASIN AND ADJACENT FEATURES.

HOHOKAM PETROGLYPHS

A DANGEROUS HUG!

One of the really interesting locales in south-central Arizona is Casa Grande Ruins National Monument near Coolidge (about one-half way between Tucson and Phoenix).  The site was given the designation of archaeological reserve by President Benjamin Harrison in 1892 (the first such designation).  In 1918 President Woodrow Wilson declared the site a National Monument.  The National Park Service (NPS) refers to the inhabitants and builders as Ancient Sonoran Desert People but most people simply call them the Hohokam.  They evidently were agrarian people and farmed the desert with the help of an extensive system of canals, mostly along the Gila and Salt Rivers.   The NPS believes the Hohokam lived in the area for over a thousand years until around 1450.  At Casa Grande the people built a "big house” (Spanish = casa grande) that the NPS believes is one of the largest prehistoric structures ever built in North America; remains of the four story “house” are still visible today.

While hiking with, and following, my brother in the hills south of Casa Grande (I was actually looking for zeolites in the basalt) we were treated to the sight of hundreds of Hohokam petroglyphs, and foundations of some sort of ?buildings.  While the buildings at Casa Grande are composed of caliche, all we observed were rock foundations.

 

I have observed numerous petroglyphs (“pecked” into rocks) and pictographs (painted on the rocks) in the red rocks of the Colorado Plateau, and even in my native Kansas on the Dakota Sandstone.  The Colorado Plateau glyphs and graphs are the work of artists associated with the Barrier Canyon Culture and the later and better known Fremont Culture.  However, this is the first time that I have observed glyphs on basalt boulders.  But, I guess artists work with the media available!

mike

A BUILDING FOUNDATION?

LIZARD GLYPH

A STORY WITH A LIZARD

BIGHORN SHEEP

SANTA CATALINA MOUNTAINS

SANTA CATALINA MOUNTAINS LOOKING EAST FROM STATE PARK.  BOUNDING PIRATE FAULT RUNS THROUGH AREA IN FOREGROUND.

The Santa Catalina Mountains dominate the skyline east of Tucson and are a typical Basin and Range chain with large bounding normal faults on either side.  West of the Catalinas (along the highway) is the Canada del Oro Basin, a graben filled with several thousand feet of sediments eroded off the high mountains.  The coalescing alluvial fans (debris shed off the retreating mountains) from the Catalinas seemed to have merged with similar fans coming off the Tortolita Mountains (west of the Basin) about one Ma (Bezy, 2002) (Fig. 6).  Most of the sediment in the Basin is composed of pieces of granite, schist and their mineral components such as feldspar, quartz and muscovite.  This seems logical since the western mountain front is composed dominantly of different types of granite emplaced during the Precambrian (Oracle Granite, 1.45 Ga) and the Tertiary (Wilderness Suite Granite, 45-50 Ma; Catalina Granite, 26 Ma) (Bezy, 2002) (Fig. 7).

The major drainage along the western front of the range is the south-flowing Canada del Oro with tributaries coming down from the mountains and joining it at right angles.  Most likely this rather straight-flowing stream follows the course of the western bounding fault termed the Pirate Fault.   Mt. Lemon at 9157 feet is the highest point in the Catalinas and has a ski resort---not a very good proposition in most dry winters.  The name, Santa Catalina, may have been bestowed by a Jesuit priest, Eusebio Francisco Kino, who was busy converting the Tohono O’odham (local Native Americans) to Catholicism in the late 1600’s.  As with many places in the west, Spanish miners soon followed in the footsteps of the proselytizing priests.  They evidently found placer gold in a creek and named it Canada del Oro or Gulch of Gold, a name that has intrigued me for the several years that I have been coming to Tucson. 

The area also has its share of lost mine stories, although nothing to quite match the Lost Dutchman up at Apache Junction.  Most of the tales seem concerned with the Iron Door Mine (gold) and La Esmeralda (silver) in the northern section of the Catalinas.  Clay Thompson of the Arizona Republic in the 10 December 2007 edition reported: “at some point in the 1750s or 1760s Jesuit missionaries feared for their lives, either because of a revolt by their Native American charges or because of attacks by the implacable Apaches.  So they stashed a whole bunch of silver and gold in either a mine or a cave somewhere in the mountains north of Tucson and sealed it with a heavy iron door - minas de fierro con puerta en la Canada del Oro. Then the Jesuits lit out for friendlier environs, and over time the exact location of the treasure was lost.

Lots of people have searched for it over the years, but obviously, no one has ever found it, if, indeed, it is there to be found.  One of the people who believed in the legend was Buffalo Bill Cody, who owned some mines in the area at one time and looked around a bit for the Mine With the Iron Door.

In 1923, a popular storyteller named Harold Bell Wright cranked out The Mine With the Iron Door, a novel featuring brave and honest prospectors, a plucky orphan girl, a wrongly accused hero and a couple of villains named Sonora Jack and Lizard.  The novel was made into a movie of the same name in 1924 and again in 1936.”

There is at least one region, the Southern Belle District but sometimes referred to as the Catalina or Oracle District, that actually has produced both lode and placer gold.  The mine, “a former surface and underground Au-Pb-Ag-Cu-W-silica mine”, evidently was closed in 1964.  “Mineralization is a tabular ore body” hosted in rocks of the Precambrian Apache Group (exposed between the Oracle Granite and the Catalina Granite).  Mineralization in the quartz veins “is probably associated with a Lower Cretaceous-Tertiary intrusive period” (www.mindat.com). 

I have thus far been unable to gain access to the Southern Belle property, so I did the next best thing—grabbed my gold pan and tried to locate a placer deposit in Canada del Oro.  I did find a single small piece of flour gold but not much else.  Toole (2007) suggested that since the stream course contained 60-200 feet (actually I think it is much greater) of “overburden” then the gold would be down on the bedrock.  But he also opined that perhaps a metal detector (which I do not own) could locate surficial nuggets. 

My lack of success with the pan is probably the norm for Canada del Oro.  It appears that for several years after members of the local Native Americans quit discouraging exploration, miners tried to make a living with placers but activity seemed unsustainable over the long term.  Wilson (1933) reported “numerous old pits, trenches, and tunnels indicate considerable early placer mining, and many thousand dollars worth of gold are reported to have been recovered.  The production recorded from 1903 to 1924, inclusive, amounted to $11,351 [this was at $20 gold] …During the 1932-1933 season, approximately thirty men intermittently carried on small scale rocking and panning in the Canada del Oro region, chiefly on the northern side of the creek.  Although one $25 nugget [1.25 oz] and a few $5 nuggets [.25 oz.] were reported, the average daily returns per man were seldom more than fifty cents”. 

REFERENCES CITED

Bezy, J. V., 2002, A Guide to the Geology of Catalina State Park: Arizona Geological Survey, Down-to-Earth 12.

Toole, D., 2007, Where to Find Arizona’s Placer Gold: Delos Toole Gold Books, Salem, Oregon.

CANADA DEL ORO BASIN IN MIDDLE DISTANCE.  LOOKING WEST FROM CATALINA MOUNTAINS WITH TORTOLINA MOUNTAINS IN FAR DISTANCE.