Tuesday, August 9, 2016

Titus Canyon: The Upper Part of Lost Canyon

As we descend the west side of Red Pass and enter the realm of Titus Canyon proper—as opposed to being just on the Titus Canyon road—the geology becomes a little more complex than the Tertiary-to-the-north–Cambrian-to-the-south scenario that we've been seeing since leaving Tan Mountain. Just for the heck of it, I’ve shown a little of the geologic complexity of the area below, although the contacts I’ve drawn, using Google Earth’s “Add Path” tool, are merely the ones I’ve felt the need to investigate during the course of writing these little blurbs about Titus Canyon: They by no means represent all the geology, nor are they guaranteed to be accurate or precise. And I’ll probably add a few more lines before we reach Titus Canyon’s alluvial fan!
Geologic contacts are in cyan and other colors; faults are thicker lines in dark blue, dark purple, and magenta. Geology is modified from Niemi (2012) and Reynolds (1974, also as seen in Lengner and Troxel, 2008).
On the last bit of our journey along the Titus Canyon road, we had stopped to briefly consider the geology of Tc Hill, and we had nearly reached the sharp turn at the western base of Red Pass. We have now fully entered the southeasternmost branch of upper Titus Canyon.

There are three branches to upper Titus Canyon. The longest branch, the northern or western, runs about 5 miles almost due south from its headwaters near Alkali Spring; this branch is labeled Titus Canyon on topo maps. The second longest branch, the southern or southeastern, runs about 2.5 miles northwest from Red Pass; though unnamed, we're calling this branch Lost Canyon after Lengner and Troxel (2008) and others. A third branch, the eastern or middle, runs about 2.4 miles southwest from headwaters in the volcanic hills near the California-Nevada border; this branch is also unnamed, and I'm not aware of any local or regional designations for it. The three branches meet just below Leadfield.
The three branches of upper Titus Canyon: The main, west or north branch, aka Titus Canyon, is in purple; the unnamed middle or east branch is in yellow; and the unnamed southeast or south branch, aka Lost Canyon, is in red.
At the western base of Red Pass, the road takes a tight curve and heads west-northwest, closely following the dry wash that cuts through this upper section of Lost Canyon. The gradually crumbling, oft-times slumping, but still-steep cliffs of colorful Tertiary beds dominate the skyline to the north. To the south, the rocks are a bit of a mishmash: Though most of the hilly slopes are underlain by several different Cambrian formations, a few irregular and nearly level reddish patches harbor the poorly exposed, lower Tertiary Titus Canyon Formation, and a batch of locally coalescing rocky knobs expose rugged masses of dark gray Tertiary megabreccia.
Beyond the gray Tertiary megabreccia immediately on our left (south), I spy the maroon color often indicative of Cambrian Zabriskie Quartzite (Cz).
Immediately ahead, the road abandons its close proximity to the wash and passes into a half-mile by quarter-mile upland plain painted red by the lower Titus Canyon Formation. It is at just about at this point in the road that I often become fascinated by the cliff to the north and have to stop to take a few more photos.
We've been calling this cliffy hill "Tc Hill" for the reddish brown formation that caps it, although we could have gone with "Tm Hill" for the Timber Mountain Group tuffs that we can't see beyond and above the upper, dark brown cliff.
This is a perfect spot to review the geology, which is basically a faulted stack of Eocene to Miocene sedimentary and volcanic units: Titus Canyon Formation (EOgtc), possible Panuga Formation (Tg?), Wahguyhe Formation (Tw), and one or two ash-flow tuff formations within the Crater Flat Group (Tc).  The contact between the Tw and the overlying Tc is unclear, but it's probably either right beneath the reddish brown cliff labeled Tc, or it's right below the uppermost, thin whitish layer just below that, or it lies below the cream to pale yellow cliffs below the whitish layer. It's too bad that contacts—which are inconstant constructs that can move with changes in stratigraphic nomenclature—aren't drawn across the land!
Tc Hill, with some geologic formations and a few contacts drawn in.
The dark cyan line between the Tg? and Tw might be one strand of the Fall Canyon Fault Zone (a more definite strand is in dark blue), or it might be a regular stratigraphic contact.
This part of the countryside reminds me of those wonderful desert paintings by Georgia O'Keeffe.
Red rocks on a pink, yellow, and green slope.
As we traverse this relatively flat area, the road will cross several rills and washes coming of the cliff to the north.

The road continues on. The contact between the lower Titus Canyon Formation and the underlying Cambrian units (that's quite an unconformity between the Cambrian and the Eocene!) is now almost immediately south of the road, between us and the main dry wash of upper Lost Canyon. As we cross several rills and washes coming off the cliff to the north, we'll pass low slopes of gray Carrara Formation and bulges of dark gray Bonanza King Formation. If we look closely, we might spot a few old workings dug into these older formations, hinting that we're getting close to the old mining camp at Leadfield.

Now, as we near the end of the reddish upland, the road swings wide and to the south, and we're suddenly aiming toward a lumpy hill of dark gray rock. This is one of several large bodies of megabreccia composed of limestone fragments and blocks (limestone and dolomite?), which lie at or near the base of the Titus Canyon Formation. Stock and Bode (1935), who described and defined the Titus Canyon Formation shortly after H. Donald Curry's discovery of a Titanothere in what became known as Titanothere Canyon (Protitanops curryinow part of the Brontothere family; read more about this story at Geotripper), included the "limestone breccia" as a basal part of the larger Titus Canyon Formation. In the many times I've driven by these breccia bodies, I've always assumed they were part of the Paleozoic section of the area! Next time...
The reddish road, pointing toward a jumble of dark gray rocks in this Google Earth ground-level view, is about to make a tight turn to the right.
This tight turn signals that we are about to descend into the Leadfield part of Lost Canyon, and that we are nigh onto the roughest part of the road.

Now that we've passed this tight curve, the road has a steep drop off to the dry wash immediately to the left. Across the wash, there's a great view of one of the larger dumps of the Leadfield mining camp.
A partly wash-eroded mine dump sits below a large, dark gray outcrop of Tertiary megabreccia. Cambrian Zabriskie Quartzite forms a maroon cliff in the upper part of the photo. 
I was a little surprised to find that the oldtimers were digging into what's long since been determined to be monolithologic breccia formed of angular clasts and blocks of Bonanza King Formation, that is, not the Bonanza King Formation itself. Although I haven't examined this working in the field, I'm going to note a few things from the photo as though I was looking at it from an exploration standpoint. First, a bit of a hedge: It's very hard to tell what the oldtimers were after without actually making a visit to the site (all I've ever done is drive by).

A first thing to note is that there is a fair amount of iron oxide on the dump—and on the rock outcrop immediately to the right of the dump, and also on the slope coming off of the Fe-oxide-barren dark gray carbonate breccia (reportedly the breccia might consist of both limestone and dolomite). The iron oxides consist of goethite, hematite, and jarosite based solely on the color seen in these photos (hopefully the color balance of the photos is good), the oxides are leaning toward goethite and jarosite. (Here, I'm using the old porphyry copper, Bear Creek–originated triad of hematite-goethite-jarosite, even though jarosite is technically a sulfate, not an iron oxide. Someday I'll have to try to do a color triangle to show what we used to use.)

Secondly, I'd like to note that someone took the time and effort to shore up the flat area in front of the adit feeding this dump with fairly cruddy hand rocking (left of the dump and best seen in my next photo).
Here you can see the dump and rock wall a little better. The adit opening is behind a largish creosote(?) bush.
Oldtimers were interested in a number of things, just like we are today. They would have been more attracted to the rocks with iron oxides, although iron oxides by themselves aren't indicative of anything besides the oxidation of iron, and iron oxides aren't necessarily all that uncommon in carbonate country. The oldtimers would have liked any quartz vein material they might have seen floating around, and they would have noticed any gossanous material that might indicate the weathering of sulfides. They also knew how to follow structures. Adits, like the one that created this mine dump, were often dug to either follow structures or to intersect them.

The biggest anomaly I see in the photo is the abrupt, semi-linear contact between the unoxidized, cliff-forming dark gray rocks and the oxide-bearing, slope-forming grayish orange rocks. It's possible that the oldtimers were trying to hit this contact. Maybe there was a little indication of "mineral" upslope, maybe not. It's a little hard to for me to imagine that this particular dump was created solely as part of a stock scam, as has often been claimed for nearly the entirety of the Leadfield camp.

That is, if I was doing any exploration in this area (I don't conduct exploration in National Parks or Monuments; it doesn't pay), I'd be remiss if I didn't take at least one sample from this dump, and if I didn't try to find something to sample either in the back or ribs at the adit opening, or on the hill above it. Maybe I'd only try to grab (select, or "high-grade") a sample of iron oxides in blebs, veinlets, or on fractures. I'd also be remiss if I didn't at least look for a "goodie pile" left by the last claimholders, although erosion by the wash might have taken it away.

So much for armchair exploration! Here's a bit of the geology near the adit:
Cbl = Cambrian Bonanza King Formation (should be "Cb or Cbk"); EOgtc = Eocene to Oligocene Titus Canyon Formation; Mbx = Tertiary/Paleogene, probably Eocene megabreccia in or at the base of the EOgtc.
After rounding the next bend, we'll be descending into the lower part of Lost Canyon...into the Leadfield basin. The road is on the side of a fairly steep, rocky hill, and we come to what is probably the worst part of the road overall: the part where you might get high-centered if your clearance isn't good enough or if you hit it at the wrong angle.
The road passes over a barely scraped, overhung exposure of Tertiary megabreccia.
We descend, switch back to the south, and there's a great pullout for hiking back to the mine dump and adit we just viewed.
From this trailhead you can hike the short distance to the mine dump we just viewed, and one or two other dumps along the way.
Most mine adits and shafts don't have all these hazards, but most have a few to several. Don't go in if you don't know what you are doing, and don't assume you know what you are doing. It's my humble opinion that you don't.
Well, there we are: We've arrived in the lower part of Lost Canyon, in the valley or basin that the ghost town of Leadfield occupies.

A Few 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.

Reynolds, M.W., 1969, Stratigraphy and structural geology of the Titus andTitanothere canyons area, Death Valley, California [Ph.D. thesis; not available online]: Berkeley, University of California, 310 p.

Reynolds, M.W., 1974, Geology of the Grapevine Mountains, Death Valley,California; a summary, in Death Valley region, California and Nevada, Geological Society of America Cordilleran Section, Field Trip 1 Guidebook: Death Valley Publishing Company, Shoshone, California, p. 91–97.

Snow, J.K., and Lux, D.R., 1999, Tectono-sequence stratigraphy of Tertiaryrocks in the Cottonwood Mountain and northern Death Valley area, Californiaand Nevada, in Wright, L.A. and Troxel, B.W. eds., Cenozoic basinsof the Death Valley region: Geological Society of America Special Paper 333, p. 17–64.

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

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