Saturday, October 31, 2015

Update from the Lake: It's Fall Again!

It's been a slow fall, it seems, and when I went out looking for brightly colored leaves yesterday, I didn't find all that many. One reason is that we've cut down all the aspen trees: they take over the yard and block the sun from our newly planted fruit trees and berry bushes ("newly" being in the last couple years). I did find one aspen that hasn't yet gotten pulled as the weed it is; its leaves (above) were mostly green, showing the lateness of the fall.

I went around and photographed some of the more colorful leaves.
Peach tree leaves.
Same plant; closer view.
Wild plant through rusted deer fencing.
Orange lilac leaves, with a hint of new fencing behind.
Leaf from our Surefire™ pie cherry tree.
Some of these pictures remind me of my leaf series watercolors. Maybe I'll start painting again!
This same cherry was nearly killed by a deer last year.
Leaf from our 4-way apple tree.
Not sure which of the four strains that leaf is from. Most leaves on the tree are still green, and a few went directly to brown. Not sure if more will turn yellow, but we are getting a freeze tomorrow night, so...maybe.
The aronia berry leaves have all turned bright red!
As have some leaves on the holly.
Filbert leaves, only partly turned.
Here's one of our Carolina allspice bushes next to an aspen stump.
Carolina allspice leaves.
And now, I'm back outside, under gray skies, to label plants and continue with roof tear-off cleanup. It's busy around here this fall!

Thursday, October 29, 2015

A Hike Up Glass Mountain

It was Earth Science Week, and a relatively small group of Nevada geologists went on a two-day field trip to a couple places that included Medicine Lake volcano. Here we are beginning a half mile hike to an overlook point on Glass Mountain, a rhyolite to dacite flow-dome complex that lies at the east edge of the Medicine Lake caldera (the caldera forms a small part of the greater volcano or volcanic area, AKA Medicine Lake Highlands or Medicine Lake volcanic highlands).

I took the photo of geos walking up the bulldozer road while looking straight into the sun. The almost blinding light from the sun peeking through clouds and gleaming off the numerous glassy shards and fragments of rhyolite lying on both sides of the road generated numerous lens flare spots—partly because I need a new camera! Although the effect doesn't look too bad, it was difficult to get useful pics in this direction (almost due south).

The location I've given at the end of the post is the start point of our hike (also see the embedded Google Map just above that, which shows the entire hike route). We had driven west from S.R. 139 on a paved road that is variably called County Road 97 or USFS service road 97, then we turned right onto USFS 44N01. After about a mile and a half, we turned left onto the Glass Mountain Pumice haul road, which was inactive at the time: the pumice mine doesn't operate year round. I don't know if this road is really open to the public, but signs on the road said, "Watch for Trucks," not "Keep Out."
Looking eastward from the bulldozer road at a roundish mass in the blocky rock of the northernmost dacite flow lobes, .
The road we walked up follows and climbs the steep face of the largest of the rhyolite flow lobes, where the rhyolite has partly buried a slightly older, darker dacite flow. Possibly a little breadcrust texture can be seen in the brownish-weathering mound near the foreground of the photo (above). Breadcrust texture, defined here for breadcrust bombs, results during cooling. Its presence can be taken as in indication of an original, fairly non-disturbed flow surface; the texture can also be used to identify hot (v. cool or cold) volcanic fragments in something like a lahar. Ron Schott has one example of a breadcrust-textured rhyolite from the Black Rock Desert volcanic field (UT), and Erik Klemetti has another rhyolite example from Panum Crater (CA).

Here at Glass Mountain, many of of the blocky pieces and fragments at the surface of the flows have broken during flow formation or during later physical weathering. Breadcrust texture, if present on this rounded mass, for example, would indicate that this particular surface might be an original flow surface: the surface was molten hot, then it cooled enough to form a crust, then it cracked because the interior was still hot and expanding. I'm not really sure, however, if we're  really looking at breadcrust texture.
The blocky surface of the northernmost dacite flow at Glass Mountain, with what appear to be pressure ridges or ogives.
Google Earth image of the northernmost part of the rhyolite-dacite contact area. Magenta marks the contact; a few flow lines or ridges are in cyan.
The lighter, more viscous, younger rhyolite is on the left; the darker, less viscous, older dacite is on the right.
Chunk of black obsidian with reddish oxidized (and partly devitrified?) bands.
Vesiculated obsidian (pumice or "puffed obsidian", AKA pumiceous lava flow rock, part of the rhyolite flow rather than tephra) at the end of our hike (Google Maps location).
Here's the hike, from "unnammed road" in the upper center, white, to "unnamed road" in the lower left, red. Despite the 0.7 mile one-way distance given by Google Maps, I calculated the distance on Google Earth as 0.95 miles round trip, and about 330 feet up. It took me 28 minutes to hike to the overlook; others took less time and some took more. YMMV.

Tuesday, October 27, 2015

Finding a Thesis: A Bit O' Geology in the Palmetto Mountains

My (very) rough interpretation of the Walker Lane on Google Earth.
As for the broad geology of the Palmetto Mountains area, what I knew back in the spring or early summer of 1976 was quite broad, and it probably wouldn't have filled up the trunk of my '72 Opel. The main thing I knew—besides that the region was known for its silver mining, and that the silver mines were presumably of the Betty O’Neal type (see more here; I can’t actually expound upon this much further anymore because that terminology never came into wide use)—was that I was in that confusing realm in western Nevada known as the Walker Lane (or Walker line, Walker belt, Walker Lane belt, Walker Lane strike-slip belt, and even Walker Lane mineral belt; we geologists can be overly broad and rather sweeping at times).

The Walker Lane, first named by Locke et al. (1940), is a somewhat vaguely defined, and yet locally precisely defined zone of abnormal structural trends, a zone that acts as or is the transition between the Sierra Nevada structural block and the Basin and Range province. Albers and Stewart (1972) described it thusly:
“a zone of disrupted structure at least 300 miles long and 50 to 100 miles wide that forms a transition between the northwest-trending Sierra Nevada block to the west and the north-northeast-trending ranges of the Great Basin province to the east.”
(Please note that this use of "Great Basin" may be incorrect, depending on where one terminates the Walker Lane to the north and south; i.e., the Walker Lane would be at least partly outside the Great Basin if it extends north of the Madeline Plains, and it is outside the Great Basin if it extends as far south as Las Vegas.)

(And also, by the definitions above, which reference the Sierra Nevada, the Walker Lane shouldn't continue north of about Susanville, CA; or farther south than about Las Vegas, NV, Kingman, CA, or maybe Parker, AZ.)

Different maps and figures show different boundaries for the Walker Lane, and as you can see from my interpretation on the Google Earth image, the zone gets vague to the north (or disappears) where it runs into the Cascades, and it gets vague (or meaninglessly broad) as it goes southward toward and past Vegas and the Mojave Desert. Looking at Google Earth and zooming way out, it appears that the entire Mojave could be included in this belt, and that the general trend continues southward into Mexico where the caterpillars are marching to the northwest. I don’t mean to formally extend the Walker Lane to the south like that, because as a definable and distinct structural entity it then becomes quite nebulous.

Anyway, not only was I cognizant of the existence of the Walker Lane back in '76, but I also knew that the Palmetto Mountains were located along the southern portion of the larger Silver Peak-Palmetto-Montezuma (SPPM) oroflex (Albers, 1967), a feature that is broadly part of the Walker Lane (and may have been caused by motion along Walker Lane strike-slip faults). I hypothesized (possibly fancifully; I didn't get to check it out) that an east-west structure defined by Lida Canyon on the east and Palmetto Wash on the west formed a break between the larger, well-defined SPPM oroflex to the north and a poorly formed Sylvania-Magruder oroflex to the south (which may not exist).
I've drawn the approximate trace of the Silver Peak-Palmetto-Montezuma oroflex on a Google Earth image.
Oroflex, as defined by Albers (1967, p. 145):
"a mountain range with an arcuate trend that is believed to have been inherited from tectonic bending of the crust"
Well, so much for that. Yes, we’re in the Walker Lane (and have been since before coming to the Klondyke mining district). Yes, there has been an oroflexural bending of the structures or mountain ranges of the area during formation of the Walker Lane—if that is, indeed, what really happened—sorry to be vague about this; read more at Faulds and Henry (2008) and Petronis et al. (2009). Tectonic issues can be kinda complicated!

As for Lida and the Palmettos, I would make my way back into this area a couple times in later years—and I'll probably get into these visits a little before moving on to my next thesis stop: Silver Peak.

Selected References:
Albers, J. P., 1967, Belt of sigmoidal bending and right-lateral faulting in the western Great Basin [abstract only]: Geol. Soc. America Bull, v. 78, p. 143- 156.

Albers, J.P., and Stewart, J.H., 1972, Geology and mineral deposits of Esmeralda County, Nevada [for purchase only]: Nevada Bureau of Mines and Geology Bulletin 78, 80 p., 1:250,000.

Billingsley, P., Locke, A., 1941. Structure of ore districts in the continental framework. Transactions of American Institute of Mining and Metallurgical Engineers 144, 9–59.

Faulds, J. E., Henry, C. D., and Hinz, N. H., 2005, Kinematics of the northern Walker Lane: An incipient transform fault along the Pacific–North American plate boundary [pdf]: Geology, v. 33, no. 6, p. 505-508.

Faulds, J. E., and Henry, C. D., 2008, Tectonic influences on the spatial and temporal evolution of the Walker Lane: An incipient transform fault along the evolving Pacific [pdf]: – North American plate boundary: Arizona Society Digest 22, p. 433-466.

Locke, Augustus, Billingsley, P. R., and Mayo, E. B., 1940, Sierra Nevada tectonic pattern [abstract only]: Geol. Soc. America Bull., v. 51, p. 513-539.

Petronis, M.S., Geissman, J.W., Oldow, J.S., and McIntosh, W.C., 2009, Late Miocene to Pliocene vertical-axis rotation attending development of the Silver Peak–Lone Mountain displacement transfer zone, west-central Nevada [abstract only], in Oldow, J.S., and Cashman, P.H., eds., Late Cenozoic Structure and Evolution of the Great Basin–Sierra Nevada Transition: Geol. Soc. America Special Paper 447, p. 215–253.

Stewart, J.H., 1980, Geology of Nevada: a discussion to accompany the Geologic map of Nevada: Nevada Bureau of Mines and Geology, Special Publication 4, 136 p.

Wesnousky, S. G., 2005, The San Andreas and Walker Lane fault systems, western North America: transpression, transtension, cumulative slip and the structural evolution of a major transform plate boundary: Journal of Structural Geology, v. 27, p. 1505–1512.

Previous Posts in this Series:
Thesis: Finding an Area
Finding a Thesis: Battle Mountain to Austin to Gabbs
Finding a Thesis: Pole Line Road
Finding a Thesis: Pole Line to Belmont
Finding a Thesis: Klondyke District
Finding a Thesis: A Joshua Tree Aside
Finding a Thesis: Into the Palmetto Mountains
Finding a Thesis: Farther into the Palmetto Mountains

Thursday, October 22, 2015

Finding a Thesis: Farther into the Palmetto Mountains

Magruder Mountain from Lida Summit.
The sun went down on that 1976 campsite perched somewhere on the south side of the Palmetto Mountains, and I eventually fell asleep, curled up in my barely adequate sleeping bag on the ground near my '76 Opel. Fortunately, by this time on my thesis hunt the evenings were almost balmy, so I didn't freeze the way I had during that earlier, colder stop a few miles north of Belmont. Was this trip later in the spring?—or was it really that much warmer at the same elevation but 75 miles to the south?

I arose the next morning and dinked around a few nearby workings (possibly near the Blue Dick Mine) while I grabbed a quick bite. Then I once again got out my paper topo sheets—this time it would be the Goldfield 2° sheet and the Magruder Mountain and Lida Wash 15' maps—and determined my course for the day. I would at least plan to get up to some of the prospects and workings near Excelsior Spring, and I'd try to hit a few prospects to the northwest near the Palmetto Mine.
A portion of the Magruder Mtn 15' quad courtesy of the USGS
via their Map Locator & Downloader.
I relaxed a bit as I drove down the alluvial fan road, feeling not nearly as tense as I had the day before, and then I made my way up and over Lida Summit, which sits at an elevation of 7460 feet (although it apparently was at 7400 feet as recently as 2004!).
Lida Summit looking west.
The view looks about 55 miles across the relatively low hills of the Sylvania Mountains, across intervening Eureka Valley, across a low northern part of the Inyo Mountains, and across Owens Valley south of Big Pine, at the distant peaks of the Sierra Nevada. The highest peaks in the view, toward the right approaching a dark hill beyond and below the sign, are Mount Pinchot at 13,494 feet (4113 m) and Striped Mountain at 13,179 feet (4017 m).

When I had planned my stops early in the morning, I didn't know I'd be passing by the old site of Palmetto, formerly a silver-mining community, now a complete ghost town.
The Palmetto historical marker (also read it here), in front of an old millsite.
The rock work of the millsite.
Abandoned stone building.
Looking through the old ruin up toward the highest point of the Palmetto Mountains, 9285 feet (often called the "Blue Dick Benchmark").
Both Peakbagger and SummitPost list the elevation of the Blue Dick Benchmark as 9289 feet (2831 m). SummitPost has a good story about oldtimer Blue Dick Hartman, for whom the nearby Blue Dick Mine was named. A somewhat more detailed version of him faking his own death can be read awkwardly in this view of the 1954 Tucson Daily Citizen.
Another view from the ruin (Google Maps location).
And so, on that long-ago day, I pulled myself away from the site of Palmetto and drove up a good, bladed road into the main part of the Palmetto mining district. The sun was warm as it shone through the windows of my non–air-conditioned, little blue car. I wound my way upward into the piƱon-juniper zone, which to this day often feels hotter to me than the lowlands of the same area. Maybe the air is stagnant in the trees, maybe it's something about expecting more coolth from the shade than could possibly be created by these desert trees, maybe it's the sun reflecting off the dirt of the road and the dirt between the trees. I'm not sure, but I still don't look forward to hikes in the trees, especially those of the juniper persuasion, preferring the sagebrush zone below or the alpine zone above.

I stopped at a place, maybe at the end of one of the roads, where there was an old shack (or two? or three?), a wooden framed adit or two, many rusty tin cans, a couple shot-up 55 gallon drums, old and new shards of glass, garbage and rubbish, jumbles and scrap—in sum, the usual stuff and old junk often found in old mining areas, always variable from place, always worth looking through or at least taking pictures of. I ate lunch and then wandered around, looking at the old workings and mine dumps, finding a boat load of orange shaly chips, probably float from the Ordovician Palmetto Formation.

As for the broad geology of the area, I'll try to get into that next time...

Previous Posts in this Series:
Thesis: Finding an Area
Finding a Thesis: Battle Mountain to Austin to Gabbs
Finding a Thesis: Pole Line Road
Finding a Thesis: Pole Line to Belmont
Finding a Thesis: Klondyke District
Finding a Thesis: A Joshua Tree Aside
Finding a Thesis: Into the Palmetto Mountains

Tuesday, October 13, 2015

Finding a Thesis: Into the Palmetto Mountains

Looking southeast from Goldfield Summit. Stonewall Mountain is barely peeking through the gap.
South from Goldfield, the country drops off fairly abruptly, as if preparing the traveler for their eventual departure from the Great Basin, which would happen about 127 miles to the southeast and 3020 feet downhill if the traveler continued in a southerly direction, approximately here at an obscure pass north of Vegas. In other directions, egress from the Great Basin would occur about 104 miles to the ESE and 4741 feet slightly uphill (downhill, uphill, downhill, and uphill several times) at Hancock Summit on S.R. 375, the E.T. Highway, or about 79 miles southwest and 7480 feet uphill (downhill, then uphill, then downhill, then back uphill) at "Ed Lane Peak" on the crest of the Sierra. These measurements would be as the crow flies.
The country dropping off south of Goldfield Summit. The mountains in the far distance are the northern part of the Amargosa Range on the Nevada-California boundary at the edge of Death Valley. 
By road from Goldfield Summit to Lida Junction, Highway 95 falls away 1401 feet in about 13 miles (a 2% grade); from Goldfield Summit to Beatty, it sinks another 1389 feet in about 52 miles (0.5% grade). About 86 more miles south of Beatty, the road arrives at its intersection with the Great Basin Divide, located at a vague point on an alluvial fan approximately corresponding with the junction of 95 and S.R. 156. The grade from Beatty to this point on 95 north of Vegas is almost nil. It's no wonder that the decline south of Goldfield seems noteworthy.
Lida Junction and the now defunct Cottontail Ranch.
The Cottontail Ranch was for sale when I took this picture in August, 2010. Other photos from that era can be viewed here.

Back to finding a thesis: Upon leaving the Kondyke District back in 1976, I drove south through Goldfield and then west on old Highway 3 (now S.R. 266), a paved road that shoots off of Highway 95 at Lida Junction toward the Palmetto Mountains, my next stop.
The road to Lida.
After about 19 miles of paved road, I came to the small town of Lida. Lida, currently inhabited by a smallish number of ranchers and probable retirees, is often referred to as a ghost town because of its old, abandoned buildings and townsite dating back to its short heyday in the late 1800s and early 1900s.
An old building in Lida (Google Maps location).
Populated areas, even those with a very small number of people, kind of spooked me back then – and I continue to prefer unpopulated areas when doing field work – so I made some hurried, almost furtive passes through town and then turned northward onto a dirt road, heading for one of the prospects I planned to visit the next day. The road ascended a fairly steep alluvial fan on the south side of the Palmetto Mountains. I'm no longer sure which road I took, and though I remember it being one that took off from the highway near Lida, it could have been one of a few on the west side of Lida Summit.

I make my way up the fan: I’m on a narrow, two-track dirt road in my '72 Opel. I cross a sand wash and drive past a cottonwood tree, at which point the road turns sharply and pushes itself upward. Sitting in my Opel, I am below the tops of head-high sagebrush. There is nowhere to turn around should I need to, and I’m not sure I could back through the turn and sand near the cottonwood tree. As I proceed up the fan, I notice a light-colored 4WD pickup coming down the road toward me. A little apprehension sets in: other than continuing on this road without stopping, there isn’t much I can do. I’m sure that if I stop, I will not be able to start up the hill again, but will have to attempt backing down. I look nervoulsy for places to pull over, but there aren’t any, just more and more waist- to head-high sagebrush. As I approach the truck, it pulls off the road and stops, flattening the big sage without effort. I smile and wave a little, and drive on by, not stopping. What could these more experienced people think of a young woman driving up this road in a clearly unsuitable car?

At this juncture, while I’m driving past the pulled-over truck, it’s worth pointing out that there is a thing called The Code of the West, which consists of a variable number of generally unwritten rules. One of the codes is about not asking where other people are from or much of anything about their past. Back then, I took to this first Code of the West – "Don't inquire into a person's past. Take the measure of a man [sic] for what he is today." – quite heartily: I didn’t like being asked questions about myself, and I didn’t like talking about myself. This part of the code, developed in the time of the early west when people would escape misfortune, debt, and calamity in the east by coming west and making some clean start, could allow me to continue to be semi-anonymous even amongst people I knew, and allowed me to go unnoticed, something I preferred back then.

Another, possibly newer part of the code says that the person going uphill has the right-of-way. This rule applies whether you are hiking, riding a horse, driving a carriage, or driving a vehicle. It’s especially true on dirt roads and in all mountainous country. It is incumbent upon the person going downhill to find a place to pull-over or to back up to the last pullout point. I mention this not lightly. A few years ago in northern Idaho, I found that the locals would not give way to a non-local going uphill (me) under any circumstances, even on private land not belonging to them but leased to the company I was working for. Possibly the CA plates I was runnning didn’t help matters any, and so I vowed to retrieve some old AK or NV plates for use if I ever went back. I don’t know if that would have corrected their rude, non-western behavior.

Back to the Palmettos. I continued up the road, not knowing if I would come to a dead end or if I would find a turnaround point. At the rocky base of the mountains, the road turned sharply to the left, culminating in a flat area large enough for me to turn around by making a full circle rather than by making one of those awkward, multi-point turns. A charred circle of rocks marked the place as a campsite, so I gratefully settled in, ending the day on a flat point overlooking the valley and mountain to the south. The campsite was more comfortable than my previous one near Belmont, and the weather was warmer. I watched the sun set while eating a camp-made dinner.
The view from my campsite may have looked something like this before the sun went down, although it was taken from Lida Summit, looking east.
I would spend most of the next day looking at various prospects on the south side of the Palmettos, driving up this road and then that. Fortunately, the roads had been bladed, so I wouldn't have to concern myself with the logistics of stopping, backing up, or turning around.

To be continued...

Previous Posts in this Series:
Thesis: Finding an Area
Finding a Thesis: Battle Mountain to Austin to Gabbs
Finding a Thesis: Pole Line Road
Finding a Thesis: Pole Line to Belmont
Finding a Thesis: Klondyke District
Finding a Thesis: A Joshua Tree Aside

NOTE: Some of these reconnoiters may have occurred during more than one trip, although the trips would make one fairly nice loop or out-and-back from my back-then location north of Reno.

Wednesday, October 7, 2015

Finding a Thesis: A Joshua Tree Aside

South of the Klondyke district (our previous stop on this journey) and just north of Goldfield, one reaches one of the northernmost populations of Joshua trees (Yucca brevifolia) — or the northernmost population, depending on what range map you use. These unusual plants continue southward past Goldfield toward and beyond Beatty. They occur in dense stands or forests in several places, notably along Highway 93 approaching Caliente, Nevada, and in a few places in the Mojave Desert of California.

To take the pictures I've included here, I drove off Highway 95 onto the Silver Peak Road about three to four miles north of Goldfield. Joshua trees are scattered all along the five to six miles between 95 and Alkali, Nevada.
Looking NNE toward Tonopah and the Klondyke Hills.
Joshua tree with Hasbrouk Peak to the left (reddish hill underlain by Tertiary volcanic rocks) and the Klondyke Hills to the right (brownish hills in front of the volcanic rocks of the southern San Antonio Range).
Joshua trees, especially those near Goldfield, make me think of my Former Mining Company days and Roquemore, who was the head of the Nevada District. (We were divided into four districts for exploration and management purposes, with Nevada being covered by one district’s worth of geologists. Our district, the Western District, covered all Pacific states up and down the coast from SoCal to Alaska, and we claimed Hawaii, though we were never lucky enough to be stationed there). Roquemore told me — years after my thesis-hunting pass through the Goldfield area when we were exploring Mineral Ridge near Silver Peak as part of a Nevada-Western joint venture — that Dusty, a dark-haired young woman working in the Nevada District, always waved at Joshua trees every time she saw one; she would wave while saying, “Hi.” Dusty had claimed that Native American tribes, or a particular tribe, believed the Joshua trees held or were the manifestations of the spirits of their ancestors, an assertion that I haven’t been able to verify by Googling.

While listening to this story on that day gone by, we drove past another two dozen Joshua trees, and Rock waved out the window, saying, “Hi,” in a immitation high-pitched voice.
Wild horses amongst the Joshua trees.
I'm not sure what the Nevada District geo-types were doing in Joshua tree country. We of the Western District would later claim as ours all areas where chollas could be found, and gave this new territory, which went as far north as the Gilbert mining district in the Monte Cristo Range west of Tonopah, the name “Cholla District.” Possibly the Nevada geos were out looking at something down near Caliente; possibly they had ventured into Goldfield, Silver Peak, or even as far south as Beatty. Nevertheless, every time I see a Joshua tree, I think of Rock saying hi in that high voice, I think of Dusty’s story about the spirits of ancestors in Joshua trees, and I find myself, on occasion, waving.

The Finding A Thesis series will continue onward, past Goldfield and into the Palmetto Mountains.

Read more about Joshua trees at DesertUSA.

Previous Posts in this Series:
Thesis: Finding an Area
Finding a Thesis: Battle Mountain to Austin to Gabbs
Finding a Thesis: Pole Line Road
Finding a Thesis: Pole Line to Belmont
Finding a Thesis: Klondyke District