Goodbye...

...to the old mine.
Hello, way off in the distance, to the new.

I've started a new contracting/consulting job in a new place, a gold mine up on one of the Nevada gold trends, a move from copper to back to gold. I'm still in exploration rather than production, that aspect hasn't really changed. Some of the particulars have changed, some particulars remain the same or nearly the same. (The same and not the same: geology, geochemistry, drill rigs, core, RC chips, logging, samples and sampling, microscopes, cross-sections, various investigative instruments, PPE, geologists, techs, support contractors and companies, etc.)

The gold trend mines (Carlin trend, Eureka–Battle Mountain trend, Getchell trend, and Midas trend) are often, though not always, a long way from towns and cities (primarily Elko, Carlin, Eureka, Battle Mountain, and Winnemucca). The two major companies and some smaller companies facilitate transportation to the mines with busses and vans. My regular 10 hour work days are now lengthened by 45 to 60 minute drives or rides in both directions. My time from doorstep back to doorstep in the morning to late afternoon or early evening runs from about 4:30 am to about 5:00 pm, sometimes a bit earlier or later depending on variable logistics. Consequently, the time I currently have available for blogging is a little limited.

I'm also getting resettled in the new town, not really quite yet moving out of the old town in the hinterland of eastern Nevada. This process may take as much as a couple-three months. In other words, I'm fairly busy on my days off. There is also a whole new area to explore and investigate.

I'll post when I can!

Backroads: Too Cold to Change a Flat, and other Considerations

Upon getting out of the truck at the north end of the Monitor Valley playa, it became rapidly clear to me that it was very cold. (Later, the weather calendar for Eureka showed a max of 28°F and a min of-3°F for the day.) When I pulled off to the side of the road, possibly running over some spiky twigs from the roadside saltbushes, I hoped I wouldn't get a flat tire. I then immediately reassured myself that my fairly new tires still had good tread, and that *of course* I wouldn't get a flat.

By the time we got back to the truck after our excursion a relatively short distance out onto the playa, my fingers were freezing and my face was icy. I once again considered the chances of getting a flat from running over thorny bushes, so instead of turning around in the middle of the road, I drove a short way to a wider turnaround spot. I decided then that I wouldn't change a tire if one happened to go flat: it was just too damned cold. Instead, I figured I would immediately get into the back of the truck and climb into one of our -20°F sleeping bags. (Well, maybe I would have run the heater to warm my hands up first, but I wouldn't have wanted to use much gas. MOH, however, says we wouldn't have had a problem changing a flat, so maybe he wasn't as chilled!)

After getting back on the Monitor Valley Road, we proceeded north past Diana's Punchbowl, a travertine hill with inset bowl or depression containing hot water that will presumably boil any living thing that falls into it (reported temperatures range from 138°F to 200°F), and drove on to Potts Ranch Hot Springs, where we ultimately decided that the water was too cool for the outdoor temperature that I guessed was possibly as low as 5 or 10°F — or maybe it was 15°F with a wind of 7 mph, or 20°F with a wind of 10 mph. The average wind at the Eureka Airport was 7.4 mph that day, with gusts from the northwest, though we remember a breeze from the south.
At some point, either at the hot springs, or more likely as we were heading up the road past The Geographic Center of Nevada, we had a brief discussion about the cold and what we would do if the truck broke down on this relatively desolated, but mostly good, graveled road.

What would we do if the truck broke down out here? Would we walk to the nearest occupied ranch? Well, no, we'd stay with the truck and probably get in our sleeping bags, which were in the back inside the metal Caravan camper.

We had some food (and coffee), along with a Coleman stove for heating some of the water we had brought with us — water we had carefully preserved from freezing by placing in a large ice box. Although our food was really meant for two days and the second day was getting on toward dusk, we could stay with the truck awhile before getting too hungry or thirsty. The nearest active ranch that I knew of, the Monitor Valley ranch, was about 7 miles from Potts Ranch Hot Springs, about 11 miles SSW of the sign for the geographic center, and maybe about 14 or 15 miles back from the place where we started this conversation. Highway 50, at this point, was "only" 11 or 12 miles to the northeast. We had just passed a sign that said a ranch was off to the east up some side road, but I had no idea how far up the road the ranch might be, or whether the ranch was active.

So, had we broken down during the late afternoon or dusk of early evening, we would have stayed with the truck. We could try to spot ranch lights by dark, giving us a better idea of what we might to do by the light of the next day.

Would we activate one of our SPOTs to send a 911 message? Well, probably not right away.

I suspect that the Monitor Valley Road is fairly well traveled ordinarily, although I haven't been on it routinely for many, many years. I would expect at least one or two ranchers or other travelers to come by per day, even in the dead of winter. We would have, therefore, stayed in the truck hoping for someone to come by the next day instead of sending a SPOT 911 call right away and incurring possible search-and-rescue charges. Because we had really only packed food for two days, we might have been getting low on food by the end of the second, unless I still happened to have a stash of old canned food somewhere in the back of the truck, which I doubted.

If no one had come down the road by noon to mid-afternoon of the next day, we would have faced the same choice: walk, stay another night with our dwindling food and adequate water, or SPOT a 911 call. (There was no cell service, as far as I know.) I suspect that we might have stayed another night and then walked or sent a SPOT call for help on the third day, but we didn't end up having to make that choice.
I had been thinking about some of these possibilities since stopping at the north end of the Monitor Valley playa. There, we could have considered walking to the far side of Diana's Punchbowl, where warm or hot water flows in a creek coming from the eastern base of the spring mound. Reasons not to walk? I didn’t know the temperature of the water, our trek would have taken us farther off the main road than we already were, and we would have been going away from the shelter of the truck. (One can always burn tires for heat.) I suppose we could have carried food and some water along with our sleeping bags, but in my mind, no tent means no real shelter, and we didn’t have a tent to carry with us. Additionally, the warmth factor of the water, which I remembered as warm but not hot, was in question. (It turns out that the water was probably warm enough at about 110 to 120°F.) All in all, we would have faced similar circumstances and made similar choices as we might have made farther to the north: we were about 0.5 miles from the main road, about 4 miles from Diana's Punchbowl, and about 9 or 10 miles from the active Monitor Valley ranch.
Had we broken down at Potts Hot Springs, we would have stayed overnight, maybe getting warm in the springs before retiring to our sleeping bags (and maybe not, since the water was only around 100°F), leaving us to face the same choices the next day. Potts, however, is closer to the active Monitor Valley ranch — it's about 7 miles away — making it fairly likely that we would have walked the next day. Seven miles is still a fairly long hike over the repetitive ups and downs of the main road, which crosses alluvial fans coming off the east side of the Toquima Range, but 7 miles is feasible. We would have still been taking a chance by walking away from the shelter of the truck; but in this case, the truck was on a side road and probably not visible to the rest of the world, and we would have been walking down a main road, visible to anyone that might happen by.

An active ranch doesn’t necessarily have people present, but if no one is home, one can presumably break in if needed, make a phone call (if there is phone service), wait for people to come, or send a 911 call via SPOT while one waits indoors.

After all this consideration during the course of two hours or less, I realized that I really haven't done much field work out in the middle of nowhere in very low temperatures during the middle of winter. Also, when I did that sort of thing at all, other field partners were likely to have been waiting back at the motel, ready to go out looking if necessary. For this wintry trip, we had blithely traversed at least 90 miles of dirt roads by the time we had reached the geographic center of Nevada, and I hadn’t given the temperatures and our relative isolation a second thought until late afternoon: those roads and that area had become familiar to me over the years, although most of my familiarity dates back 20 to more than 30 years ago.

I think I'll at least take more food with me the next time I go out into the chilling cold.

South by West of Center: Monitor Valley Salt Flat or Dry Lake

We were driving up Monitor Valley towards Potts Ranch Hot Springs (yes, up is north in this case), when we both spotted a strange whiteness on some hills located just north of the playa in the center of the valley. I had noticed this phenomenon at this site once before, but had attributed the light coloring of the hills to white beds of sediment, poorly welded ash-flow tuff, or air-fall tuff in the Tertiary volcanic section, and hence, had just driven on. This time, it looked as though dust or salt had blown northward off the playa.

We decided to check it out. We turned right on the decent side road that crosses the valley, drove to the closest whitish hill, and stopped amidst some white to very pale green bushes. The unnamed playa is located about 23 to 24 miles south by west of The Geographic Center of Nevada. (MSRMaps location).
I'm assuming the bushes are fourwing saltbush, or Atriplex canescens, in its wintry, somewhat non-leafy form.
Yes, they are covered by a thin coating of a white salt, an encrustation that flaked off easily into my hands.
To investigate this phenomenon further, we walked out onto the playa, a soft playa characterized by crusts. The photo (above) shows how the bushes gradually lose their salt crust going away from us along the northeastern playa edge, and shows part of the Monitor Range in the distance.

The crusty, soft surface is partially covered by windblown detritus.

The wind direction while we were out there was from south to north (right to left in the photo), which explains the salt coating on the bushes, unless the salt coating developed when winds from the south were blowing across a playa covered or partially covered with water.
When the playa surface is examined closely, circular features can be seen in the crusts. These circular patches will come up as blocks if prodded, and are (I hypothesize) most likely some form of biotic or cryptobiotic crust.
Looking back to the north toward my truck: the salt on the bushes is somewhat variable in distribution, apparently thinning away from playa's edge.
Now I turn and look down the five-mile length of the Monitor Valley playa. Monitor Valley continues another 25 miles beyond the south end of the playa, ending in the faint turquoise mountains in the far distance: the southern part of the Monitor Range. There is water on the playa in the far distance on the left (hard to see in this shot), and we have spotted a couple unknowns on the ground in the middle distance.

We decide to walk across the soft, crusty surface to see what's out there.

It's an old, salt-encrusted wooden post, fallen from its previously upright position, along with some other stuff of unknown origin or purpose. Picking the post off the playa floor pulls up the salt crust, revealing white to pinkish crystals on the bottom of the crust. I didn't try a taste test.

Salt crusts (possibly partly biogenic) out near the wooden post.

Salt encrusted wood, looking for all the world like driftwood.

And now, for the cold walk back to the truck.

De Re Metallica

A—Twig. B—Trench.

Prospecting by twig and trench, as shown in one of my favorite books, De Re Metallica by Agricola. Source of image: Wikimedia.

Therefore a miner, since we think he ought to be a good and serious man, should not make use of an enchanted twig, because if he is prudent and skilled in the natural signs, he understands that a forked stick is of no use to him, for as I have said before, there are the natural indications of the veins which he can see for himself without the help of twigs. So if Nature or chance should indicate a locality suitable for mining, the miner should dig his trenches there; if no vein appears he must dig numerous trenches until he discovers an outcrop of a vein.

For a miner must have the greatest skill in his work, that he may know first of all what mountain or hill, what valley or plain, can be prospected most profitably, or what he should leave alone; moreover, he must understand the veins, stringers[1] and seams in the rocks[2]. Then he must be thoroughly familiar with the many and varied species of earths, juices, gems, stones, marbles, rocks, metals, and compounds. He must also have a complete knowledge of the method of making all underground works. Lastly, there are the various systems of assaying substances and of preparing them for smelting; and here again there are many altogether diverse methods.

[1] Fibrae—"fibres." See Note 6, p. 70.

[2] Commissurae saxorum—"rock joints," "seams," or "cracks." Agricola and all of the old authors laid a wholly unwarranted geologic value on these phenomena. See description and footnotes, Book III., pages 43 and 72.

Quotes are from De Re Metallica at Project Gutenburg,
Book II and Book I, respectively.

Read De Re Metallica at Project Gutenburg.
Read De Re Metallica at Internet Archive.

This post has been submitted to Accretionary Wedge #43 at In the Company of Plants and Rocks.

UPDATE: Geologic Illustrations Galore -- Accretionary Wedge #43 is now up!

South of Center: Potts Ranch Hot Springs

I'm not exactly sure where to start on the way to ending up at Northumberland Pass and the Northumberland caldera, so we'll start at The Geographic Center of Nevada and work more or less backwards in time. MOH and I had taken two trips to Austin, with major and minor side trips into the caldera and to Spencer Hot Springs on both trips.

On the second trip, we ended our second day at the sign for the geographic center. We started in Austin, drove over Austin and Bob Scott Summits on snowy roads, went down old Highway 8A (now NV S.R. 376) in a dust storm, crossed Big Smoky Valley on the graveled Northumberland Mine road, and meandered into the central and south part of Northumberland caldera on good and cruddy dirt roads. We then proceeded back to the Northumberland Mine road, went up Northumberland Canyon, crossed Northumberland Pass, and headed down East Northumberland Canyon into Monitor Valley. It had been a long day. My photos began at 9:40 a.m. in Austin and ended at 4:35 p.m at the north end of Monitor Valley after a road trip of more than a 100 miles, not counting our side trip into the caldera.

Our first stop on this backward trek is Potts Ranch and Potts Ranch Hot Springs, located about 16 to 17 miles nearly due south of center.

Potts Ranch ranch house.

We drove into Potts Ranch from the south, following tentative directions heard the night before at the International bar in Austin, which assumed that we'd be coming in from the north via the Pete's Summit road. Fortunately, I also had a set of printed out topo maps, although the ones I had didn't name Potts Ranch or give a name to the nearby hot springs. Potts Ranch is shown on the 7.5' topo map of the area.

A stone building just behind the ranch house.

Our verbal directions mentioned this stone building, so we knew we were on the right track.
It was a frigid afternoon, and ice covered the flat north of the dirt road approaching the ranch house, where the creek flowing north from the hot springs must have overrun its banks. Other ranch ruins can be seen in the distance on the right, and cows are grazing in the far field on the left. Sastrugi shapes in the snow suggest a dominant wind direction from the north whenever the snow was blowing, though the wind was blowing from the south while we were there.
Here we're looking south at the frozen creek and at two reddish brown hills of Tertiary ash-flow tuff. To get to the hot springs, we'll drive just north and then east of the closest hill, then we'll follow a rutted dirt road all the way to the south end of the far hill.
The tub was empty when we arrived, so we moved the three black plastic pipes onto the metal rail so the filling process could begin. We also plugged the drain hole.
I think the idea is that you can fill the tank with one, two, or three of the pipes depending on what temperature you prefer. We wanted the water to be as hot as possible.
While waiting for the tank to fill, we walked around and looked at the marshy, grassy wetlands, which is drained by several steaming hot creeks. The Toquima Range is in the background.
A second hot creek in the foreground and a distant hot creek in the background give off steam, again with the Toquima Range in the background.

Another view of the same hot creeks.

Here I've walked around to a small warm or hot pond that may be fed by the same spring feeding the bathing tub. The Monitor Range, on the east side of Monitor Valley, is in the background.

Frozen grasses on pond's edge.

About this time, with the tub almost half full, we realized that neither one of us wanted to face the chilling wind or experience the icicles that would hang off our hair and face after bathing in the not-quite-hot-enough water (reported at around 100°F). We pulled the three black plastic pipes off the metal rail, unplugged the drain hole, and got in the truck.
We stopped at the spring source of the hot creek that supplies water to the soaking tub, before driving out and back to the main road north.

Green plants growing along (and in) the hot creek downstream from its source spring; ice on grass or sedge.

Green to light bluish plants or algae, waving or rippling in the flowing water.