Showing posts with label molybdenum. Show all posts
Showing posts with label molybdenum. Show all posts

Tuesday, May 10, 2016

Death Valley Trip, Getting There: Black Rock to Lida Junction to Beatty

On this leg, we will finally make it into Beatty! Yay!!

In our last episode we were at Black Rock (it should be Black Rock Point, or something, but isn't) checking out Lone Mountain and the Boss Mine. Before leaving, I managed—with my handy-dandy, relatively new Nikon DSLR with 18-300 mm zoom—to get this shot of the far-away Crescent Dunes solar thermal power plant, which reportedly went online in February.
The power tower and mirrors of Crescent Dune in front of the San Antonio Mountains. Part of the defunct Hall moly mine can be seen on the far left. The tower is about 18.5 miles distant in this photo.
And then we got back in the Jeep and proceeded down the road toward Tonopah, where we had some coffee and a snack, and went on our way—again.

As we drifted south from Tonopah, side roads tried to distract us from our goal of reaching Beatty that night. So much to see! So many possibilities! We resisted being drawn astray (resistance is sometimes but not always futile), but upon spotting the first batch of Joshua trees just north of Goldfied, we gave in and pulled over to take a look.

It turns out that we pulled over only to take photos of a tree I had photographed in 2010 and posted about here.

Several views of my favorite Joshua tree:
Relatively close view of the large-ish Joshua tree we stopped for.
 This particular tree is not far from Highway 95 and is just a skip and a jump down the Silver Peak Road. It might, therefore, be one of the more photographed Joshua trees in Nevada. Here it is on Google Street View.
A closer view.
We were unclear about a few non-branching types of yucca (next two photos), but I think this is probably a young Joshua tree.
Unbranched yucca with Lone Mountain on the horizon.
A closer view of the leaves of the non-branched tree.
The entirety of the Joshua tree from the first two photos. Lone Mountain is on the left (NW); the hill going into Tonopah is over there on the right (N).
I just noticed the snow-capped range beyond Hasbrouk Peak and the other hills near Tonopah. This is the high part of the Toiyabe Range, including Toiyabe Dome (11,361 ft, 3463 m) and possibly Arc Dome (11,773 ft, 3588 m), which is the highest point in the Toiyabes.

There was a weak to moderate desert pavement across the area, and we hunted around for ventifacts. Not sure if these two rocks qualify, but they do show typical varnish:
The varnished rocks are probably probably volcanic.
More Joshua trees against the backdrop of the volcanic mesas to the west.
We got back on U.S. 95 and headed south, passing through Goldfield, and pulling off the highway just one more time just north of Lida Junction. I looked down a dirt road I'll probably never travel, a road leading mostly into the unexplored Nellis area.
Stonewall Mountain is partly in and partly outside Nellis, so it's possible I'll get up to the west side someday, to look at those brightly colored volcanic rocks.
Sunlit alluvial fan rills, shadows on the colorful mountains, and Joshua trees.
We were ensconced in our Beatty motel room by 4:45 pm. We didn't waste any time before going out to find some food.

Location map

Related Posts (in order of posting):
Death Valley, "Super" Blooms, Turtlebacks, and Detachments
Death Valley Trip, Part 2: More of the Badwater Turtleback Fault
Death Valley Trip, Part 3: Northward, and over Daylight Pass
Death Valley Trip, Getting There: Wave Clouds beyond the Sierra
Death Valley Trip, Getting There: A Hike to Pleistocene Shorelines

Death Valley Trip, Getting There: Walker Lake, Road Stories, A Bit about Copper, and Some Folds near Luning

Death Valley Trip, Getting There: A Jeep Trail, Folds and Cartoons of Folds, Even More Folds, and Boundary Peak

Death Valley Trip, Getting There: Highway 95, Redlich, Columbus Salt Marsh, and Another View of Boundary Peak

Death Valley Trip, Getting There: Coaldale, Black Rock, Lone Mountain, and the Boss Mine

Thursday, April 14, 2016

Death Valley Trip, Getting There: Highway 95, Redlich, Columbus Salt Marsh, and Another View of Boundary Peak

After lunch, MOH and I drove back into Mina and turned south on Highway 95, continuing our journey toward our next stop (shown above and way down below), and our more distant destinations of Beatty and Death Valley, .



As a rule, I don't write much about U.S. Route 95—that preeminent north-south highway in the west ultimately connecting San Luis, Arizona with the Eastport, Idaho, border crossing into Canada—although I see that this is the 25th post tagged 95. I personally have traveled over a good deal of this road, missing out only on the southernmost portion south of Yuma and most of the northernmost section north of Moscow, Idaho.

Through Nevada, Highway 95 wanders around quite a bit, attaining a nearly north-south bearing only within four relatively short sections: 1) the Winnemucca to McDermitt section, 2) a section south of I-80, running from Trinity to Hawthorne, 3) the Tonopah to Lida Junction section, and 4) the section running from Boulder City to the California state line. Much of 95's wanderings, especially those that occur between Hawthorne and Las Vegas, are caused by the highway's attempt to stay within the state while being subjected to Nevada's western diagonal border. To do that, the road keeps cutting east, then south, then east again, every now and then actually attaining near parallelism to the diagonal, while completing three major south-to-east curves. These curves are at Hawthorne, at Coaldale Junction, and at or just south of Beatty.

From Hawthorne south, there are several opportunites for an unsuspecting traveler to veer from Highway 95 into California; a few of these occur at the three main south-to-east curves. (I always think of 95 as though I'm headed south, not just because in this series of posts that's the direction we've been and will be going, but probably because I'm often eyeing it from a northerly position.) The first—and second—potential deviations into CA from Highway 95 occur in Hawthorne, a town now largely bypassed by most road warriors. At the main light (the only light?), you can access both of these routes by driving south on paved S.R. 359. This road will take you south and then southwest into California, where it will become California S.R. 167. You'll end up on the north shore of Mono Lake south of Conway Summit. I don't think I've ever made this trip in either direction, but maybe, back in the way distant past... Prior to that, however, you have what I consider an even better opportunity to cut into California: Take the dirt road over the Wassuk Range into the Borealis mining area, past the Aurora turnoff, and then meander along the East Walker River north of Bodie to Nevada S.R. 338 and California S.R. 182, paved roads that will almost directly have you in Bridgeport, CA.

At Coaldale Junction, Highway 95 joins U.S. Route 6, essentially coming to a T while making it's second grand curve to the east. If you are persuaded to turn west, you might end up in Bishop, CA, by way of Basalt, Montgomery Pass, and the small berg of Benton. But before that, near a little jog at a place called Tonopah Junction, you might get suckered into heading into California at what is essentially a Y with S.R. 360, which cuts over to Route 6 at Basalt.

Beatty, just north of the third south-to-east bend in Highway 95, offers two alternatives for anyone wanting to leave the state before ending up having to drive through Vegas; both options require a sojourn into or through Death Valley. The most obvious of these escape routes is the paved Daylight Pass road, S.R. 374 in Nevada, which leaves Beatty at it's only stoplight. But before you make it to the stateline on this paved road, a one-way dirt road cuts straight west into Death Valley by way of Titus Canyon. We'll be taking that latter road later (ha!), and we'll be visiting the Nevada-California stateline along Route 6 even later than that.



MOH and I watched ourselves at Tonopah Junction, to make sure we didn't accidentally get sucked into California before we were ready. After ignoring said cutoff, we begin our ascent up to Redlich Summit.

We passed the turnoff to the Candelaria mining district, and soon arrived at Redlich Summit, an apparently obscure summit with surprisingly poor location information on the web (see my location map for the actual location if you are interested). Redlich Summit lies just north of an old gold exploration project mapped and drilled by Former Mining Company in the late 1980s, which we always called just called "Redlich." A little bit of Redlich's geology and exploration history can be found here and here. In the second linked report, it would seem to me that the reporting geologist confused Former Mining Company for another exploration company with formerly similar initials.

I had thought about stopping at Redlich to take a couple pictures for a story about the area, but we breezed on by in favor of looking for some ferrimolybdite, which as you might suspect from it's name, carries some molybdenum (Mo). I wasn't sure exactly where the collection spot was, but remembered it was at a color anomaly caused by hydrothermal alteration. We pulled off the highway just south of the main hill at the old Redlich property.
Some drill roads at Redlich, on the south side of the hill sometimes known as Conglomerate Hill (also seen in the first photo).
The canary yellow ferrimolybdite that I remembered from some field trip back in the late 70s or early 80s, maybe the same one I had learned about plating copper from what looks like plain-ole Mn-oxide while working for Northern Exploration Company, had been easy to find along a dirt road just west of the highway. I could tell without spending much time that this first pullout wasn't the spot, but we looked around a bit anyway.
The view from south of Redlich, looking SE toward the Monte Cristo Range.
A somewhat weak desert pavement had formed in the area.
While walking up the drainage looking for ferrimolybdite, I spotted this nice specimen of a cholla.
It's probable that the ferrimolybdite site noted for the Red Hill area (sometimes conflated with the Redlich mine, as in this Mindat list), is about 2 miles south of where we pulled out. We missed the turn, somehow, and instead pulled out at the historic marker for Columbus, an old borax mining town located to the west along the edge of the Columbus Salt Marsh.
Historic marker #20 can be read here. Boundary Peak in the White Mountains is out there beyond the salt flat.
I zoomed in to get a closer shot:
The north end of the White Mountains.
Montgomery Peak (13,441 ft or 4097 m) is a mere blip of a hill in California; Boundary Peak (13,140 feet or 4005 m) is the highest point in Nevada.
We turned back south, drove by Coaldale and made the second big south-to-east curve toward Tonopah and beyond.

Location map

Related Posts (in order of posting):
Death Valley, "Super" Blooms, Turtlebacks, and Detachments
Death Valley Trip, Part 2: More of the Badwater Turtleback Fault
Death Valley Trip, Part 3: Northward, and over Daylight Pass
Death Valley Trip, Getting There: Wave Clouds beyond the Sierra
Death Valley Trip, Getting There: A Hike to Pleistocene Shorelines

Death Valley Trip, Getting There: Walker Lake, Road Stories, A Bit about Copper, and Some Folds near Luning

Death Valley Trip, Getting There: A Jeep Trail, Folds and Cartoons of Folds, Even More Folds, and Boundary Peak

Monday, September 5, 2011

Report on an Afterwork Field Trip

This will be a brief field trip report from an undisclosed place and an undisclosed time. In fact, other such field trips over the years, whether during or after work, might be worth reporting on occasionally, mostly sans photos.

It was a sunny afternoon, approaching early evening, and several colleagues and I passed by some broken and brecciated road cuts while on the way to our various evening destinations, wherever they might have been. The purpose of the rather spontaneous mini field trip was to shoot the bull about the meaning of the road cuts and see if we could figure anything out—in other words, to get our creative thoughts flowing. Lines and crude cross-sections were drawn in the dirt on the side of the road, with less crude versions drawn in some field books.

Our first stop was essentially a mess of fractured, broken, and shattered rocks showing varying degrees of iron-staining and oxidation. Some jarositic-looking, weakly clayey limestones formed a possibly arched, upper zone above more typically calcite-veined dark gray Devonian limestone cut by hematitic seams and hematitic fracture-fill fines. Discussions ensued about what iron-oxides were staining the rocks and filling in fractures. A reddish coloration—reddish brown to reddish orange brown—in a batch of rocks, sometimes present in broad areas or even over whole mountains, is supposed to be a good sign when one is looking for the upper oxidized to leached portion of a porphyry copper system — at least according to a few old-timers who told me about such things back in the late 1970s when porphyry copper exploration had come to a standstill after what turned out to be a long-term decline in the price of copper.

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An Aside: A long time ago, Bear Creek or Minefinders developed a color triangle for determining the composition of various limonites or generic to mixed iron-oxides. Powdered pure or nearly pure jarosite (a sulfate containing iron that can form as a weathering or oxidation product of pyrite) was placed in a circlular spot in the upper corner of the triangle, powdered pure goethite was placed in the lower left corner of the triangle, and powerdered pure hematite was placed in the lower right corner of the triangle. Three other circles were placed between the three corners, each composed of 50-50 mixes of the appropriate two of the three main powders, and one circle in the center contained the three end members mixed together. To summarize the triangles main colors, jarosite is pale yellow to white when powdered or scratched, goethite is the typical dark golden brown of the average "limonite," and hematite is its typical reddish brown. I've looked high and low for an online version of this field cheat sheet that consisted of stiff cardboard with clear plastic- or cellophane-covered circles of powders with appropriate labeling, but have yet to find anything resembling the original. Perhaps I'll draw up something similar to the original and go further into this little exercise in crude field determinations sometime at a later date. For now, back to the field trip.

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I developed a question or two as we were standing beneath the large fractured to brecciated mass of structurally complex reddish to yellowish brown pile of carbonate rocks: (1) were we looking for copper and (2) doesn't the same guide to ore (red rocks and reddish color anomalies) also apply to finding porphyry molybdenum deposits? I also wondered (3) haven't red rocks been considered a guide to ore in at least some disseminated gold districts, for example at and around Florida Canyon? The answers: (1) maybe [seriously, what we were looking for was actually in question], and it is good to define what you are looking for without getting so stuck on what you've decided to look for that you can't see the possibility of finding something else, (2) yes, for sure, something I first learned from other not-quite old-timer types, also back in the late 1970s, and (3) well, of course, but not everywhere.

Our impromptu field trip then moved down the road to stop number two, where a breccia of unknown origin was exposed in a particularly hairy road cut on a tight curve with narrow shoulder and the occasional speeding vehicle. The breccia reminded me of the Titus Canyon megabreccia: mostly angular fragments of dark-colored carbonate rock were cemented by white, crystalline calcite. I thought it looked like a breccia of possible hydrothermal origin, one in which fragments had shattered but not moved far. It also looked a bit like a tectonic breccia, though no faulting surfaces were exposed. The expounder leading this part of our field trip said it could be a collapse breccia that formed over an oxidized massive sulfide deposit. Oxidation of sulfides produces volume loss, leaving a potential collapse waiting to happen. I'm not sure how the calcite gets into position to cement the breccia together, it somehow having to push the fragments apart to exploit the collapsed zone, but some long, thin beds of shaly limestone could be seen to be sagging downward in a couple places, testifying to possible collapse. Perhaps the breccia was really fragment supported instead of apparently matrix supported, in which case the calcite could have moved in later with groundwater or low temperature hydrothermal waters of some kind.

Resulting major questions arose from the two field trip stops and all the bull that was being shot around. One major one that was oft repeated: Should we drill here? Or there? Or over there? Everyone wanted to choose their own drill hole or two and locate them in specific favored spots. Another question: Should we sample here? The answer to that question? If you have to ask the question and don't just pile in with your bags, labels, and rock hammers, the answer is an automatic yes. Conclusion: get on with it! ASAP.

And so ended a spontaneous early evening field trip to two undisclosed field trip stops, along an undisclosed highway, at some vague undisclosed time within the last 10 to 30 years.

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Torrent, José, and Barrón, Vidal, 2002, Diffuse Reflectance Spectroscopy of Iron Oxides (see page 1441 for Munsell color of some iron oxide minerals).

Somewhat Related Posts:
Some Thoughts on Weirdness, and A Picture (or Two) (or Three)
Megabreccia II: More Photos
Megabreccia III, the Continuing Saga

Friday, April 11, 2008

Speaking of Slag and Silver


Here are a couple photos of slag from the north end of Eureka, Nevada, to go along with Maria's post and some great photomicrographs of slag here and here. Another slag pile from a different smelter, on the south end of town, looks about the same. The slag piles were formed from the smelting of the dominantly lead-silver ores of early Eureka days - smelters were active starting in 1869. Much more recently, starting sometime in the 1970's, gold has been produced from several mines in and near Eureka, and molybdenum was discovered by ASARCO at nearby Mt. Hope in the 1970's and may go into production by 2010.
UPDATE: Antimonite has recently posted a photo of iron slag from 700 A.D.

References:
http://www.westernmininghistory.com/towns/nevada/eureka/
http://en.wikipedia.org/wiki/Eureka%2C_Nevada
http://generalmoly.com/index.htm