Forged by Fire • Treasured Through the Ages
Typical shapes of Mule Creek Marekanites; size range averages 1 to 5 cm, although some may go as large as 10 cm.
Among the wide range of volcanic rocks and minerals that can be found near Casitas de Gila Guesthouses, one of the most interesting is obsidian. In geologic terms, obsidian is classified as an extrusive igneous rock or sometimes a mineraloid, but never as a mineral because it does not have a crystalline structure. Instead it is a naturally-occurring amorphous volcanic rhyolitic glass, formed when a magma or lava flow, highly rich in SiO2 cools so rapidly that crystalline minerals do not have time to form. Typically, obsidian contains between 70 and 75% SiO2, substantial amounts of magnesium oxide (MgO) and iron oxide (Fe3O4), plus numerous trace elements, such as rubidium (Rb), cesium (Cs), strontium (Sr), barium (Ba), lanthanum (La), cerium (Ce), yttrium (Y), titanium (Ti), zirconium (Zr), phosporous (P), tantalum (Ta) or niobium (Nb).
Obsidian is easily identified by its glassy, conchoidal fracture and its brown or smoky-gray to black color. Sometimes it may contain inclusions of small, white crystals of the mineral cristobalite, a high-temperature form of SiO2, or it may contain linear or swirling patterns of extremely small gas bubbles retained within the flowing magma or lava before it was rapidly cooled.
Perlite showing bedding layers and swirling texture
Obsidian is found around the world wherever rhyolitic magma (containing 70% or more SiO2 and less than 2% water) occur. In the United States, obsidian occurs in most western states and is abundant within western New Mexico and Arizona. Similar deposits of obsidian occur just south of the border in the Mexican States of Sonora and Chihuahua.
Obsidian is not stable at the earth’s surface and consequently is rarely found in rocks more than a few tens of millions of years old. The reason for this is that over time, ever so slowly, obsidian absorbs water into its structure, and once that happens the obsidian converts to another natural glass or mineraloid called perlite. Thus, many volcanic deposits that originally formed as obsidian are now entirely converted to perlite. Not all perlite deposits form from hydration of obsidian, however. If a rapidly cooled, rhyolitic magma contains 2% or more water to start with, then the resultant volcanic glass will solidify as perlite, not obsidian.
THE MULE CREEK REGION OBSIDIAN DEPOSITS
Mule Creek Country. Outcrop of rhyolitic ash flow deposit in foreground.
The geologic history of western New Mexico during the Late Paleogene to Early Neogene Periods (old terminology Mid to Late Tertiary) was basically a time of extensive and ongoing volcanic activity. By the end of Oligocene Epoch the lengthy period of massive eruptions of the Super-volcanoes within the Gila Wilderness (35-28 million years ago) had come to an end, and the focus for most of the ensuing volcanic activity within the Grant County/Catron County, NM, border area over the next 10 million years or so during the Miocene Epoch shifted westward towards the Arizona/New Mexico border and into eastern Arizona. It was during this time between 20 and 17 million years ago that the obsidian deposits of the Mule Creek region were formed.
Broken Marekanites displaying conchoidal fracture
Extensive research by M. Steven Shackley, Department of Anthropology at the University of California at Berkley, regarding archaeological sources and use of obsidian in the American Southwest indicates that the Mule Creek Obsidian Deposits are probably the most extensive occurrence geographically of obsidian anywhere in the Southwest. The deposits are located about 20 miles northwest of the Casitas and occur within a greater than 100 square mile area that centers around the small community of Mule Creek, New Mexico, about five miles from the Arizona border. Within this vast area that includes portions of Grant and Catron Counties in New Mexico and Greenlee County in Arizona, are numerous, extensive obsidian-bearing volcanic rhyolitic ash flow deposits. When found in place, the obsidian occurs as small nodules, generally two inches (5cm) or less in diameter, but occasionally up to twice that size, within outcrops of perlitic ash-flow deposits that absolute dating shows were ejected 17.7 million years ago.
Close-up of Marekanites in Perlite matrix layer within Mule Creek rhyolitic ash flow deposit
The scientific name for these obsidian nodules is marekanites which take their name from the Marekanka River in the Okhotsk basin in Siberia, Russia, where they were described over a hundred years ago. A more recent, common name that is often given to these obsidian nodules is that of “Apache tears”, a name coined by mineral collectors, rockhounds and lapidary enthusiasts for the obsidian nodules found in the American Southwest. In addition to the widely distributed outcrops of marekanite bearing perlite deposits of the Mule Creek Obsidian Deposits, the obsidian nodules also occur as a significant constituent of virtually all Quaternary Period alluvium deposits which have been eroded from the bedrock outcrops and redeposited in stream beds and valleys throughout the region.
TREASURED THROUGHOUT THE AGES
Perlite layer within Mule Creek rhyolitic ash flow
Obsidian has been a treasured natural resource of prehistoric and historic cultures worldwide since the beginning of the Stone Age because of its glassy composition and conchoidal fracture, allowing the rock to be easily worked into extremely sharp projectile points, cutting blades and other tools. Because of its limited occurrence, good sources were highly sought after by prehistoric cultures, most likely fought over, and became the basis of early production centers, commerce, and trade routes.
Archaeological research of the late pre-historic cultures of the American Southwest and Northern Mexico conducted by Dr. Shackley at the University of California at Berkley and research done as part of the Preservation Fellowship Program at the private non-profit organization Archaeology Southwest has shown that the Mule Creek Obsidian Deposits were extensively mined and utilized by early cultures, and that the raw obsidian nodules and probably partially finished products (called blanks) were widely utilized and traded within in New Mexico and Southern Arizona. The evidence for this is based on analyzing the trace element composition of obsidian artifacts, and then comparing the results with the trace element composition of known obsidian source deposits.
Mule Creek cross-bedded rhyolite and perlite ash flow deposit
Extensive analysis of numerous obsidian source areas has shown that the type, amounts of, and the ratios of various trace elements within a source area are essentially unique, and thus can be used as a diagnostic tool for determining the source of the material used in an artifact’s manufacture, as well as providing clues as to distribution patterns and possible trade routes for the raw material.
Today obsidian is still used in the manufacture of precision cutting tools such as scalpels used in surgery. The reason for this is that a fractured edge of obsidian is far sharper than any surgical steel blade manufactured. Research on the effectiveness of obsidian scalpels has shown that wounds heal faster, with less scarring, and without complications.
The use of obsidian in jewelry, stone carvings, and sculptures goes back for thousands of years and continues today, where it finds abundant use in inexpensive, mass-produced jewelry, as well as high-end artisan jewelry, and as a carving stone for sculptures.
MULE CREEK OBSIDIAN AT THE HIGHWAY’S EDGE
Close up of Marekanites in alluvium, weathered out of Mule Creek rhyolite and perlite ash flow deposit
For travelers who delight in taking the road less travelled, the most scenic route between the southern Arizona cities of Tucson and Phoenix and Casitas de Gila Guesthouses involves a spectacular one-hour drive through the Apache National Forest in Arizona and the Gila National Forest in New Mexico over AZ/NM Highway 78. About five miles east of the Arizona/New Mexico border, NM 78 passes through the small community of Mule Creek, which has a US Post Office (at least at the time of this writing), but no other stores. Near the sign for the post office there is a dip in the road where the typically dry Mule Creek crosses the road. For the traveller in a hurry, a one-minute stop here at the side of the road will almost always produce a couple of nice Marekanites left behind by short-term flooding of Mule Creek during periods of high runoff from the surrounding hills. For the more serious rockhound or geology afflicted souls, rest assured that longer visits into the surrounding Gila National Forest in this area can provide anywhere from a day to a lifetime of memorable geological experiences!
Hiking the Mogollon Box Trail — Gateway to the Gila Wilderness
Entering the Gila Riparian Preserve on the Mogollon Box Trail
A short six miles upstream from the communities of Gila and Cliff, New Mexico, the Gila River exits the soaring mountains and rugged canyons of the Mogollon Range of the Gila Wilderness within the Gila National Forest to begin a more leisurely, meandering flow westward across the verdant Gila Valley. This transition from a narrow, steep-sided, volcanic rock-lined canyon to the wide alluvial floodplain of the Gila Valley, with its magnificent bordering groves of ancient cottonwoods, sycamores and willow, is as abrupt as if it had been carved by some gigantic knife of Nature. Which, in one sense, it has, for it is here that the Gila River crosses a major east-west fault separating the uplifted terrain of the Mogollon Mountains and the Gila Wilderness from the down-dropped lowlands of the Gila Valley. This very special natural area is known as the Mogollon Box or the Upper Box of the Gila, the Gateway to the Gila Wilderness.
Looking north into the Gila Wilderness
For the hiker and nature enthusiast, the Mogollon Box Trail offers a unique opportunity to connect with an amazing diversity of topography, geology, fauna, and flora for several miles along the pristine waters and surrounding riverine forest of the Gila River. Adding to the complexity of this landscape is the presence of Mogollon Creek, which has its confluence with the Gila at this transition spot, after flowing some 20 miles in from the west, along the base of the Mogollon Mountain escarpment and its headwaters high in the 10,000- to 11,000-foot mountain peaks of the Gila Wilderness.
The trail climbs a ridge carved from ancient river deposits
The Mogollon Box Trail begins by traversing a 1,200 acre parcel of land known as the Gila Riparian Preserve. Originally a privately-owned farm and ranch, bordered on all sides by the Gila National Forest, this land is now owned by the Nature Conservancy and is open to the public (map available). Animal and bird life are prolific within the Gila Riparian Preserve because of the wide diversity of available habitat, ranging from the year-round, cool, clear flow of the Gila River through quiet, deep pools and swift, gravelly shallows; to active floodplain deposits of sand and gravel, interspersed with numerous natural levees along old river channels now covered with young riverine forest; to marshy, abandoned channels and cutoffs; to sequentially elevated levels of older vegetated river terraces; to gently-rolling upland high-desert hills and ridges cut by dry-wash arroyos; to shear cliffs and ledges of volcanic bedrock … all to be found within a narrow riparian zone extending a few hundred feet either side of the Gila River itself.
Looking north from the ridge and upstream at the Gila River Riparian Preserve
Descending the ridge of ancient river deposits to the modern floodplain
A shady passage beneath an old Arizona Alder (Alnus oblongifolia)
Literally hundreds of bird species frequent the Mogollon Box over the course of the year because of the dependability of food and water, including many rare and endangered species, such as the Southwestern Willow Flycatcher (Empidonax traillii extimus). Within the river and riparian zone, numerous fish, amphibians, reptiles, and mammals are found, such as the common Smallmouth Bass (Micropterus dolomieui), the boistrous Canyon Treefrog (Hyla arenicolor), the rare Gila Monster (Heloderma suspectum), and the shy Coati (Nasua narica). In addition to these, sightings of more typically upland species are common, such as Mountain Lion (Pumua concolor), Black Bear (Ursus americanus), Bighorn Sheep (Ovis canadensis) and Mule Deer (Odocoileus hemionus), as they make their way down from the surrounding hills and mountains to drink, forage and prey. As always, best sightings will be made during the hours of early morning and late afternoon to dusk.
The Common Scouring Rush (Equisetum hyemale) contains silica within its structure, making it an excellent natural scouring pad for cleaning pots and pans on the trail
One-seed Juniper, Prickly Pear Cactus and Sotol Agave (Dasylirion whelerii) growing on a soilless outcrop of rhyolite welded tuff
Mostly Prickly Pear Cactus, Mesquite, and One-seed Juniper survive on ancient river deposits
The plants of the Gila Riparian Preserve are equally as diverse, ranging from gigantic ancient, old-growth Freemont Cottonwood (Populus fremontii) and Arizona Sycamore (Platanus wrightii) towering over the flood plain, to the arid, ancient, elevated river terraces and upland hills with their sparse cover of Engelmann Prickly Pear (Opuntia engelmannii), Honey Mesquite (Prosopis glandulosa), and One-seed Juniper (Juniperus monosperma).
Lunch at the USGS Gila River Gaging Station
With the exception of a short climb up and over a 100-foot-high ridge composed of ancient river outwash and flood plain deposits (encountered just after crossing Mogollon Creek), the first 2 miles of the trail is within the Gila Riparian Preserve and is very easy to hike and follow as it lies entirely along the Gila River floodplain, following an old road (closed to public vehicles) to the US Geological Survey Gaging Station on the Gila River. The gaging station is an interesting feature itself, having measured stream flow on the Upper Gila River on a daily basis since 19271. About 200 feet beyond the Gaging Station, the trail fords the river, whereby the Mogollon Box Trail soon enters lands of the Gila National Forest.
Trail along the Gila River
Rubber Rabbitbrush (Ericameria nauseosa) and flood-deposited debris cover the floodplain
An old Arizona Sycamore soon to be taken by the river
Once the first ford is crossed, the Mogollon Box Trail can become much more challenging both physically and mentally depending upon the season of the year and effect of recent floods. Often, especially in late Summer or after Spring floods, the condition of the trail degrades from faint to non-existent as it follows the Gila River upstream along a narrow floodplain through a series of deeply-incised meanders within steep-walled canyons where heavy riverside vegetation brush may require the breaking of new trail, and steep, rocky cliffs to the water’s edge demand frequent fording of the river. While it is possible to hike from the Gaging Station upstream about three miles to access Turkey Creek Road (Grant County Rd. G2-24, FR 155) at Brushy Canyon or Brock Canyon, it must be stated that due caution must be taken if this portion of the trail is attempted. While beautiful as only the Gila River can be, this stretch of the river is essentially pure wilderness – isolated and rarely travelled. It is only doable at certain times of the year, depending on the height of the river, and is especially problematic during Spring runoff and the Summer monsoon season (end of June through mid-September) when flash floods are common. Local knowledge on existing conditions should always be solicited before undertaking this part of the trail.
Heading home after a great hike
Directions to the Mogollon Box Trail
From the community of Gila take NM 211 towards the community of Cliff. Approximately one-half mile after passing over the Gila River bridge, turn right on Box Canyon Road (NM 293). Follow this road 5-1/2 miles to enter the Gila National Forest where the road becomes a county-maintained gravel road. After about 1 mile the road will drop down off an old river terrace to the modern Gila River floodplain. As soon as the road reaches the bottom of the slope, park on the left (GPS Coordinates N33° 02.665′, W108° 31.935′). Begin walking due north at this point along an old dirt path/4×4 roadway where, in about 100 feet, you will encounter a chained gate with an opening through the fence just to the right of the gate. This is the southern boundary of the Nature Conservancy’s Gila Riparian Preserve. Walk through the opening and continue, following the old roadway for about 2 miles to the USGS Gila River Gaging Station (GPS Coordinates N33° 03.691′, W108° 32.243′). The old roadway is the trail.
Directions to the US Forest Service Mogollon Box Recreation Area (at the beginning of the Mogollon Box Trail)
At the place where you park your car you are on Gila National Forest land. You will notice that at this point the road that you drove in on turns abruptly east and then south with a maze of numerous paths/primitive roadways leading off of it towards the river. The main road continues south for about 1/2 mile, providing access to the USFS Mogollon Box Recreation Area for walking, swimming, camping, and picnicing along the Gila River on Gila National Forest land. On a hot summer day it serves as the perfect local swimming hole. An outdoor toilet will be found along the southern access road.
1. Geomorphology of the Upper Gila River Within the State of New Mexico, Mussetter Engineering, Inc., June 2006
Billings Vista Bird Sanctuary & Trailhead for FT 746
Two week ago, two of our good friends from County Kerry, Ireland, spent a few days with us at Casitas de Gila Guesthouses while touring the American West. At the time, the lightening-caused Whitewater-Baldy fire had been burning for two weeks in the heart of the Gila Wilderness some 20 miles to the northwest of us. Since our guests were avid hikers, and the Forest Service had closed some of our usual hiking trails due to the fire, we decided it was a good opportunity to explore a different part of the Gila National Forest: the Burro Mountains.
The Gila National Forest is huge, offering some 1,500 miles of trails within its 3.3 million acres, and while we have spent a lot of time hiking and exploring the Gila country over the past 13 years, at best we have only scratched the surface, having a tendency to take our various visiting guests to the same favorite areas over and over again.
New Mexico's Burro Mountains in the Gila National Forest
Lightening caused fires in the Gila Wilderness are a common occurrence, and during the 13 years that we have lived in Gila we have witnessed several such events. As with previous fires in the Wilderness, the Whitewater-Baldy fire was not affecting the Casitas in any way, either by smoke or other problems, since the Casitas are located south of and, due to prevailing winds, upwind from the Gila Wilderness and the fire. So with prevailing wind in mind, we decided that a good choice for our hike would be the Burro Mountains, about 9 miles south of the Casitas. Most of the Burro Mountains, about 250 square miles or 160,000 acres, lies within the Gila National Forest. It is an interesting and varied mountain range, steeped in history, that is transected by the Gila River at its northern end, and an area which we had only briefly visited a few times before.
THE BURRO MOUNTAINS – AN ANCIENT LAND WITH A RICH HISTORY
Geologically, the Burro Mountains display a fascinating and extremely complex history of ancient sedimentary deposition; deep burial; deep seated, magmatic, pluton-forming activity; repeated uplift and erosion; accumulation of thick layers of welded tuff following explosive volcanic caldera eruptions; and extensive faulting, followed by late-stage mineral emplacement. It is a story in stone extending back over 1.5 billion years, where, today, many of the various chapters of this ancient history of the earth are exposed and laid open for all to see in the Middle Box by the eternal downward cutting action of the Gila River over many millions of years.
Across the Floodplain and into the Woods!
The more recent history of the Middle Box of the Gila is equally as intriguing. In pre-historic times, the entire length of the Gila River was a major thoroughfare for east-west travel, and was considered home to countless generations of early Native Americans such as the Mogollon Culture who hunted, fished, farmed, camped, and built villages both small and large along its course from about 150 to 1400. For the interested and observant hiker, remnant signs of these early cultures can be found in numerous places along the Gila River.
A hundred years or more after the Mogollon peoples left, the Apaches arrived and claimed this dependable desert oasis of the Gila River as home. In the years to come the Burro Mountains were at the center of much of the Apache Wars with the incoming wave of pioneer miners, ranchers, and farmers from the East. During this chaotic period, all the Apache chiefs—Cochise, Mangas Coloradas, Nana, Victorio, Chihuahua, and Geronimo—knew the Middle Box of the Gila River intimately.
In the Hall of the Cottonwoods
With the gradual taming of the West, it was inevitable that the ubiquitous and intrepid group of men known as prospectors would find their way into the Burro Mountains. And, much to their great joy and delight, here they found silver and yellow metals in great abundance. Beginning in the 1880s, and fully established by the early 1900s, several mining districts were recognized at various places within the Burro Mountain chain. Scattered throughout these rugged mountains and canyons numerous small prospects and mines were developed, yielding significant amounts of gold, silver, copper, turquoise, and fluorite1,2. Within a few decades, however, all but a few of these small mining operations had been worked out and had ceased production. But, then, just as the small mines began to close, intensive mineral exploration projects were undertaken in the southern Burro Mountains which eventually delineated the presence of extensive and massive deposits of low-grade copper ore which could be extracted at a profit, if done on a large scale. Thus was born a new phase of mining in the Burro Mountains. It is one that continues today in the form of the mega-scale operation of Freeport-McMoRan Copper and Gold Corporation’s Tyrone Mine, located in the southern Burro Mountains, about 15 miles south of Silver City. The Tyrone Mine is a huge open pit and processing facility which in 2010 produced 37.19 thousand tons of copper3.
In the northern Burros, however, most of the old mines, prospects, and workings ceased operations long ago and are now mostly forgotten and inaccessible, scattered throughout a rugged and roadless terrain.
THE MIDDLE BOX OF THE GILA RIVER AND FOREST TRAIL 746
Off We Go!
And so it, was with a sense of heightened anticipation on my part for a trail never travelled, that our two guests, two neighbor friends, two dogs, and myself set off for a day hiking and exploring Forest Trail 746 in the Middle Box of the Gila River.
In New Mexico, the term “box” is used to describe the narrow canyons along the course of a river or creek, which can serve as a handy place for ranchers to drive and corral or “box” up their wide-ranging cattle. In the case of the Middle Box, it refers to the narrow canyon cut by the Gila River as it transects the north-south trending Burro Mountain Range between the Upper Box at the edge of the Gila Wilderness upstream and the Lower Box of the Gila near the Arizona border downstream.
The Swimming Hole of the Ancients
Forest Trail 746 is a well-marked trail which leads downstream, deep into the high-walled canyon narrows of the Middle Box of the Gila River. Recently the trail has been upgraded for at least the first two miles. Substantial rock cairns mark the way across the wider stretches of sand and gravel floodplain that are devoid of vegetation, and the trail has been cleared as it goes through the dense stands of young cottonwood, willow, and shrubby vegetation that border the river channel. The trail follows the east side of the river for the first 0.7 mile, and then crosses to the west side of the river for the remaining 1.3 miles to the destination and end point of this trail discussion, the Swimming Hole of the Ancients.
The Prickly Poppy (Argemone pleiacantha) abounds along FT 746
Trail 746 is a trail that can be enjoyed by people of every age and ability. The first two miles the trail are mostly across level floodplain with only a few gentle grades. The trail meanders back and forth, towards and away from the river, first across sunlit expanses of river sand and gravel, and then beneath shady canopies of thick stands of young, 80- to 100-foot-tall Fremont Cottonwoods (Populus fremontii) that germinated along the natural levees of former floodplain channels.
In many ways, FT 746 is a passage of riverine solitude for the senses and one’s soul, offering an unforgettable, tranquil, and calming journey into the subtle essence of Gila River country. The weather on the day of our excursion was typical for the first week of June: sunny and in the mid-80s with clear blue skies and a nice breeze out of the south blowing upstream. At this late-spring time of the year, the floodplain vegetation along the river was already in full summer dress, a ribbon of green having diverse fragrant smells, and many flowers, such as Prickly Poppy (Argemone pleiacantha), lining the trail. Although the Spring bird migration had peaked a few weeks earlier, the varied calls of numerous transient species could be heard frequently, rising melodically over the ceaseless background murmur of the cottonwood leaves rustling in the canopy high above. Indeed, it was a glorious morning, and we were all reveling in it, including Red and Bower, our two canine companions.
Huge, old cottonwood washed out at river crossing
FT 746 begins by first crossing a dissected outwash plain of sand, gravel and boulders washed out from Ira Canyon to the east. It then rises briefly to cross a stretch of older river terrace of sand and gravel, densely covered with Honey Mesquite (Prosopis glandulosa) and a few One-seeded Juniper (Juniperus monosperma), before dropping down to the upper part of a broad modern floodplain sparsely covered with Rubber Rabbitbrush (Ericameria nauseosa), Seepwillow (Baccaris salicifolia) and the occasional old-growth cottonwood. After 0.2 mile, the floodplain narrows and the trail passes into a dense stand of mature cottonwood and willow which continues for another 0.2 miles. After passing through a particularly dense stand of trees, the trail then emerges abruptly at a broad, shallow river crossing. The crossing point is well marked by the remains of a huge, old growth cottonwood that toppled into creek in recent years when the river bank was undercut during a period of flooding and the eastward lateral migration of the main channel. As typical for this time of year, the flow of the Gila was low, only about calf-deep, when we made the crossing. The Spring runoff, minimal as it was this year because of a second-year-in-a-row dry La Niña Winter, had peaked several weeks earlier.
Once the river was crossed, the trail again entered into a zone of alternating stretches of floodplain sand and gravels, and dense, high-vaulted stands of young cottonwood and willow, with an understory of waist-high, thick-growth young willow trees.
The contrast in sensual perception between the alternating sunlit, barren sand and gravel, and shaded, lush vegetated tunnels of plant growth was intense and inescapable as we hiked the next half mile of the trail. Leaving the floodplain, we followed the trail as it climbed up onto the bordering mesquite and juniper covered terrace, and then abruptly emerged at the top of a 15- to 20-foot-high, white rocky promontory jutting out into the river. We had arrived at our lunch time destination, the Swimming Hole of the Ancients!
Our lunch spot, overlooking the Gila River
And what an idyllic and magical spot it is! Within less than a minute, our canine buddies were frolicking in the river, swimming, and chasing sticks, while their owners and friends relaxed at the promontory’s edge and examined the intriguing grinding holes made a thousand or more years ago by the ancient tribes that passed this way. There could be no doubt that the ancients considered this place as special as we did. The 4 to 6 inch depth of the several holes at the top of the rock promontory where they ground their maize and other food stuffs offer mute testimony that countless generations of ancient travelers had paused here to swim, rest, and eat before or after passing through the rugged, narrow, rocky chasm of the heart of the Middle Box that our map indicated was just another half mile or so downstream.
Where the Ancients ground their maize
This rocky promontory is the first outcrop of bedrock to be found within the river as one hikes downstream towards the narrows of the Middle Box, a telltale sign of the chasm ahead. The ancients, of course, knew this, and also knew that this rock was excellent for grinding grain, although they didn’t know why. It would be a thousand years or more before geologists would come to understand the why, that this abrasive rock is a rhyolite ash flow welded tuff, deposited there some 33.5 million years ago in the Late Oligocene Epoch during an eruption of the Schoolhouse Mountain Caldera, about 3 miles to the east (Ref. 1).
Time for Lunch!
Sitting there quietly munching a sandwich and observing our surroundings as the afternoon breeze rushed upstream through the leaves of the thick stands of willow and cottonwood lining the banks, it was not at all surprising when the vision of how it must have been began to play in one’s mind … a scene of young children playing, swimming, and jumping from the promontory into the river below, under the ever-watchful eyes of their mothers grinding the corn on the rocky promontory above, while the older men scoured the mesquite thickets on the hillside behind for a nice plump rabbit to round out the meal.
And then, all too soon the scene faded, and we knew it was time to pack up and head back.
DIRECTIONS FOR FINDING FOREST TRAIL 746
Trailhead Sign for FT 746 in the Burro Mountains
To reach the trailhead for Forest Trail 746 from Casitas de Gila Guesthouses, take NM 211 south from the Gila Post Office for 4 miles to US 180; turn right (west), and in 1 mile turn left on Bill Evans Lake Road. At 3.4 miles the road forks, with the road to the left leading away from the river to Bill Evans Lake. At this fork stay straight ahead for 1.9 miles to enter the Gila National Forest. After going another 4.5 miles the road leads to a designated and marked birding area with access to the Gila River. At this point continue driving south, parallel to the river, on a less travelled dirt road to dead end at the Billings Vista Birding Area and the trailhead for Forest Trail 746.
- 2005, Virginia T. McLemore, Mineral Resources of the Wild Horse Mesa Area, Northeastern Burro Mountains, Grant County, Open-file Report 486.
- 1964, Elliot Gillerman, Mineral Deposits of Western Grant County, New Mexico, New Mexico Bureau of Mines and Mineral Resources, Bulletin 83.
- Mining Almanac
The skies were dark during the April 2012 New Moon period, the Casitas were full of amateur astronomers, and the weather was wonderfully dry and clear!
We know from talking with our guests at Casitas de Gila Guesthouses that there are quite a few who have never seen the Milky Way because of the amount of light where they live. Right now the Milky Way is rising out of the southern sky in the very early morning hours. Alarm clocks are being set for 3 AM and guests are getting up to observe all of its magnificence.
Here are some photos taken by one of our April New Moon guests. Fritz Kleinhans is an amateur astrophotographer/astronomer and retired physics professor. This was his third visit to the Casitas and he is delighted to share these photos with our Casita guests past, present, and future. He’ll be back next spring, taking more photos and viewing more deep-sky objects.
Click on each picture to view a larger version.
The Milky Way
(4 minute exposure with a Canon 15mm F2.8 fisheye lens)
Deep Sky Objects
M82 (Cigar Galaxy) and M81 (Bode's Galaxy)
4 subframes, 10 minutes each, 40 minutes total exposure; two dark and one flat frame; ISO 800 with extended red filter
The scenery during the day time at Casitas de Gila is just as spectacular as the night skies!
Fritz uses a Hutech modified Canon 400D camera on a TEC 140mm apo refractor, fl=980mm, f7; Astro Tech Field Flattener with an Astro Physics Mach 1 Goto Mount