Tuesday, July 26, 2016

Down into Titus Canyon: We Leave Red Pass Behind (Finally!)

We will leave Red Pass shortly. Be sure that you've looked around: Take your last look eastward toward White Pass and Titanothere Canyon. And be sure you've gotten your fill of the hoodoos above the pass. What we'll do right now, before sliding down into the eastern reaches of Titus Canyon, will be to take one last look ahead, this time with binoculars, a zoom lens, or a spotting scope. We’ll look in the direction of Leadfield, where we can begin to see the broad fold above the ghost town.
Our zoomed in view.
I said in an earlier post that you could see the westernmost, still-standing cabin at Leadfield if you know where to look. It sits at the end of an old trail below a broad fold in the Carrara Bonanza King Formation. I have to admit that I didn’t spot this until I saw it enlarged on another website and confirmed the sighting on Ron Schott’s gigapan from Red Pass. Did you spot the cabin?
Well, there it is. Check the snapshot of the cabin on the gigapan if you're not convinced.
Before we move on, we'll take a look at the geology. As in several previous posts, the map symbols I'll use, along with the mapping (faults and contacts), are primarily from Niemi (2012) with a little bit from Reynolds (as shown in Lengner and Troxel, 2008; a tiny version of his map is shown here). These symbols are listed in an earlier post.
This matches the wide-angle photo more than the zoomed photo, but enough of that: The symbols jump around too much in Google Earth.
Essentially, we have several groups of ash-flow tuff sheets erupted from the Timber Mountain caldera back in the Miocene (Td, Tm, and Tc) lying on intermixed or intercalated volcanic and sedimentary units (Tw, the Wahguyhe Formation and Trp, the Rhyolite of Picture Rock, which consists of latite flows). The Tw-Trp mix rests on top of the dominantly sedimentary Miocene Panuga Formation (Tg, formerly the upper part of the Titus Canyon Formation) and the sedimentary Eocene to Oligocene Titus Canyon Formation (EOgtc). A megabreccia subunit composed of limestone clasts from the Bonanza King Formation forms irregular masses in the lower part of the Titus Canyon Formation. The megabreccia is shown here as Mbx; I've approximately outlined a few of the masses below. You can also see a bit of the Cambrian Carrara Bonanza King Formation [it should be labeled Cbl, not Cc] in the folded rocks sitting just above the old site of Leadfield, which, besides that one cabin, really isn't visible yet. I haven't drawn in all the contacts (in cyan): I've left a few to your imagination.
The zoomed-in photo with some geology added.
There are a number of faults in this area, and I've only shown a few (in dark blue) on the photo. Unfortunately, one of the major ones, labeled "Fall Canyon Fault Zone" (FCFZ) on Niemi's map, is really kind of hidden at this angle. I've indicated part of it in a heavier blue line, with an arrow to indicate that it's wrapping around the topography to head up toward the upper part of Titus Canyon. Please check out Niemi's map to see the complexity of the FCFZ. By the way, that upper part of Titus Canyon is kind of hidden between the closer Tw section on the right and the more distant Tw + Trp section closer to the center. It's hard to spot the canyon in my photo. Many of the other faults I've shown have low apparent dips in the photo merely because of the angle of our view. They are normal faults, as far as I know, probably of high to moderate angle—or even of low angle, at least at depth.

Now that I think about it, I'm going to have to go ahead and show this next photo, also taken from Red Pass, just so you can see the FCFZ better. Also, the upper part of Titus Canyon can be visualized more easily. I'm not sure which blue line represents the fault best: One is essentially from Niemi (2012); the other is from Reynolds (as shown in Lengner and Troxel, 2008). And both lines are what I've chosen using Google Earth, so a lot of interpretation has transpired. Both faults as drawn may be strands of the same fault. That is, to me they both look like something "fault-ish" in Google Earth. The fault on the left (west) cuts reddish and greenish beds of the EOgtc on the west. The fault on the right has light colored rocks (cream, pale greenish yellow, or light yellowish gray) of the Tw on the east (right). I'm really not sure what formation the rocks in the middle belong to, but I am sure this means that another field trip to the area is warranted.
"Lost Canyon" in the foreground; upper Titus Canyon (indicated in red) between two volcanic ridges; FCFZ in blue.
Going down the hill from Red Pass, we are finally in the greater Titus Canyon drainage area. This particular canyon is unnamed, although Lengner and Troxel call it “Lost Canyon,” using a name they say was used by Reynolds  (presumably in his 1969 dissertation), and which they also found in a report from the 1920s. Niemi used “Lost Valley” for the same area, a name that was reportedly used for the northern arm of Death Valley. I'm favoring "Lost Canyon" at this point.

Let's drop on down! The road twists and turns quite a bit, but otherwise isn't too bad. A little ways down the hill, we get a good look at this unnamed hill, herein called "Tc Hill" for the geologic formation capping the hill.
This hill is really quite colorful, and some photos I've seen of it at sunrise or sunset make it look even brighter.
I've got several sets of thin cyan lines in this next photo, and a slightly thicker cyan line at the very approximate contact between the Tc (Crater Flat Group tuffs) and the underlying Tw (Wahguyhe Formation sedimentary and volcanic rocks). The thin lines represent what look like individual beds within the formations. The yellow line outlines a talus mass or slump block.

Updated [27-28Jul2016]: The Tc-Tw contact should probably be considerably higher on the hill, putting most or all of the greenish rock into the Tw, and possibly the whitish layer just below where the rock turns pinkish to reddish orange upward. And though the line is based directly on Niemi's map, the contact doesn't really match the way he shows his contacts drawn on two aerial photos of the area (Fig. 7 and 8).
Tc Hill and the approximated Tc-Tw contact.
Now, below, I've added one strand of the FCFZ, and a couple small offsets in the cliff face. Now you see why I added the marker horizons!
Tc Hill with FCFZ and two minor normal faults added. All faults shown are down-to-the-east (right).
Although I've labeled the lower greenish rocks as Tw (that's what they appear to be on Niemi's map), it's possible that they are part of the Tg or EOgtc.

Well, that really about does it for this time! We're in the upper part of Lost Canyon, winding our way toward Leadfield. The worst part of the road (unless it has been washed out or is in any kind of flash flood situation) is waiting for us up ahead around a sharp bend. From here to Leadfield, we'll be driving mostly on the Titus Canyon Formation. I'm pretty sure that this latter fact means that this part of the road can get nasty in a rainstorm.

A Couple References:
Lengner, K., and Troxel, B.W., 2008, Death Valley's Titus Canyon & Leadfield ghost town: Deep Enough Press, 175 p.

Niemi, N.A., 2012, Geologic Map of the Central Grapevine Mountains, Inyo County, California, and Esmeralda and Nye Counties, Nevada: Nevada, Geological Society of America Digital Maps and Charts Series, DMC12, 1:48,000, 28 p. text.

Location map

Related Posts:
The Approach to Titus Canyon: Tan Mountain
The Approach to Titus Canyon: Up and over White Pass
The Approach to Titus Canyon: To Red Pass
The Approach to Titus Canyon: Just Below Red Pass
A Hike at Red Pass, Titus Canyon Road, Death Valley, CA
Titus Canyon Road: A Little History and a Few Maps

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