An unnamed portion of the Gabbs Valley Range. |
The road in question is below the arrow. |
Back to the road itself. Coming over the top from the east (something I'm not likely to do in any near future that I am aware of), the road immediately drops and dives around a curve, making it hard to judge the condition of the road ahead. We maneuvered to some particular point and stopped. What the H! We would have to do a bunch of walking to actually explore the area anyway, so maybe it would be better to stop here at this turn-around spot than to go farther and find that the road requires backing up on steep slopes around sharp turns.
I don't really remember how we handled the sampling logistics. Sometimes it's easiest to drop a couple people off near the top and then meet them at the bottom later in the day, after they've sampled the upper slopes and you've sampled the prospects in the lower hills. Or maybe after a bit of walking around, we found the road acceptable and drove on down.
The road as seen in Google Earth. It's downhill to the lower left (SW). |
The view from the upper part of the jeep trail was grand. I've tried below to simulate the view by sloppily stitching together two Google Earth images:
Walker Lake is off in the upper right (W), Luning is just left of center on the other side of the beige plain (SW); Mina is out of the picture to the left (S). |
The notable landmark of this part of the Gabbs Valley Range is a dark pimple of a peak to the right of center: Volcano Peak. |
Zooming in, we get a better view of Volcano Peak and can identify a few old porphyry copper drill roads that probably date back to the 1960s or 70s. |
In a similar Google Earth view, we can begin to see a fold nose, centered and just above the dark line (a Google Earth artifact). |
I've cropped this image so I could zoom in farther. The upper drill roads are more apparent. Volcano Peak is now on the far right. |
Before checking the geology, I came up with the following cartoon, wherein I assumed many features to be stratigraphic beds, and assigned a few other features to faulting.
Here's my first cartoon, with presumed bedding in cyan and a few tentative high-angle faults in dark purplish blue. |
After concocting the first cartoon, I checked out the geology as mapped by Ekren and Byers in 1985. It turns out that I missed a large blob of quartz monzonite (mapped as JKqm).
The quartz monzonite is outlined in red. |
These two cartoons show the problem with assuming too much from photos (or air photos). Features that look like bedding might, when field checked, actually be faults, dikes, or other structures like joints. In this when case, we checked the cartoon against a geologic map of relatively small scale, 1:48,000 or 1 inch = 4000 feet.
Somewhere in these canyons, way back in the late 1980s, we came across an old, partly broken-down core shed. The shed was mostly intact then, but the core had started to become scattered, either from vandalism or from the escalating disintegration of the core boxes (or both).
By this time on our trip to Death Valley, it seemed that we should be farther along, but we hadn't even gotten to Tonopah! So we moved on, but almost immediately we decided to stop not far down the road: it was getting to be lunchtime. Just before Mina, we pulled off the highway onto a major dirt road that goes eastward between the Gabbs Valley Range and the Pilot Mountains.
Looking southeast toward the Pilot Mountains from a broad alluvial plain above the town of Mina. Pilot Peak is hidden from view behind the unnamed, lightly snow-dusted, >8500-foot-high peak. |
While eating a cheese-bologna sandwich, I took a few photos of some of the folds. Some recumbent folds are actually better viewed from another road, but I forgot about that until looking around in Google Earth.
Folds! This is probably mostly Luning Formation limestone and shale, with some Tertiary volcanic rock in the lower left. |
More folds!! |
I turned away from the folds to take this shot of Boundary Peak. |
We'll continue our journey after lunch. We'll be stopping at Redlich and the Boss Mine. We'll see desert pavement and a cholla. We'll see Boundary Peak again. We might spy some breccia and a solar power plant.
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
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