Thursday, August 30, 2012

Sunrises through Smoke

The sun rises through a dense smoke layer above the Snowstorm Mountains, possibly near Kelly Creek Mountain, on August 12th. A northern part of the Osgood Mountains, on the east slope of peak 2506 (MSRMaps location), forms the foreground. Smoke on this morning, although from many fires, is mostly from the huge Holloway fire between Denio and McDermitt, NV, and from the Hanson fire near Paradise.
The sun doesn't quite make it through the clouds near the north side of Jake Creek Mountain on August 21st. This was a somewhat less hazy morning compared to many in the last one and a half to two months.
The sun rises over the south slope of the Owyhee Bluffs, south of Jake Creek Mountain, on August 22nd. The smoke layer is fairly dense. At this point in the month, so many fires were burning in California (and the Holloway fire was completely under control and firefighters had been demobilized from the area), that it was impossible to tell where the smoke was coming from, other than somewhere to the west. Likely candidates included the Rush fire, the Chips fire, the Pass or North Pass fire, and others.
The sun rises near the north edge of Jake Creek Mountain that same morning, August 22nd. Because of the vagaries of topography, angle of viewing, and elevation of the viewer, this is the second sunrise in one day. Sometime in July, I saw the sun rise five times over the same terrain. The air was smoky, even then, from mid-summer fires, for example the Long Draw fire north of McDermitt.
The sun rises through "the notch" in the Midas Trough, on August 23rd.
The sun rises a second time on August 23rd, at that same point on the back side, or north slope, of Jake Creek Mountain.

The Owyhee Bluffs and peak of Jake Creek Mountain are on the south (right) side of the mesa, just north of the Midas Trough. Kelly Creek Mountain is the mountain block north (left) of the lowland carved by Jake Creek, north of the rising sun (NationalMapViewer location; MSRMaps location).
A closer view of that last sunrise.
The last two mornings have been less smoky, even approaching merely hazy.

The sun is now not rising at all before I arrive at work at about 6:15 am. The sun is rising about a minute later every morning, and setting about a minute earlier, so the days are getting shorter by about two minutes every day. In south central Alaska, for comparison, the days are getting shorter by about five and a half minutes per day. The fall equinox is approaching.

Monday, August 27, 2012

Folds in Volcanic Rocks near Midas, some Wildlife, and an Aside about How to Use Lizardtech ExpressView

After passing Sawtooth dike on the Tuscarora Loop tour (driving ENE on the Midas Road into the Midas Trough), you need to immediatedly look south for the next three miles or so at some spectacular folds in rhyolitic volcanic rocks. The folds are in hills east of the junction of Evans and Clover Creeks (MSRMaps location), with photos beginning at hill 1762, above, and running to the gap southwest of hill 1938. Also see the Midas Area Google Maps view below for specific photo locations.
An enlargement of the first photo — with giant copyright notice because my online watermark site once again went down — in case the first photo was too small.
Geologic map of the Snowstorm Mountains and vicinity, Elko and Humboldt Counties, Nevada (Wallace, 1993), courtesy U.S. Geol. Survey.

The folds are entirely within an upper Miocene unit mapped by Wallace (1993) as Trpy — younger rhyolite porphyry — which consists of rhyolite and rhyodacite flows and domes.

By the way, I finally figured out how to download useable geologic maps from the USGS website. Here's the map. After downloading, or right-clicking and "Save Target As", one then needs to go here, go to downloads-viewers, and download/install the ExpressView Browser Plug-in (MrSID) for Windows. After installation, then just double-click, or right-click and "Open", the downloaded, saved map file, which has a .sid extension. The map then opens automatically in a useable page in your browser (IE or Firefox). This is so much easier than the old way, when one had to use the command line to open the saved maps. So, ignore these instructions listed as "Help in using this map" on the linked-to USGS map page. Although the instructions might be useful for some purposes, they are unnecessary for making a GEOtiff, tiff, jpg, gif, png, or bmp of a map or some portion thereof. The toolbar that comes with the viewer is a bit obscure; one does some things by right-clicking on tiny icons in the upper left and upper right corners. Saving is accomplished by right-clicking almost anywhere, which brings up options for printing, saving, and other useful items.
The main part of the hills, with some nice folds on the right.
A closer view of those folds.
These last two photos are looking at the northeastern contact area, where the Trpy rhyolite has been faulted against several formations, including the older volcanic rocks of Jake Creek Mountain — rhyolite and rhyodacite flows, domes, and ash-flow tuffs that cap the Owyhee Bluffs to the north — and the older rhyolite porphyry unit (Trpo), which on Owyhee Bluffs is fed, in part, by Sawtooth dike.

First photo, above, is from late spring; photo below is from mid-summer. The cheat grass is partly green and purplish brown in the first photo; everything has turned straw-colored in the second.
This general area, from the WSW opening to the Midas Trough to the turnoff to Midas, is a great place to spot antelope:
Antelope in early June.
Antelope in mid-July.
We also spotted a large flock of ravens coming back out of the area in mid-July...
...and several vultures feeding on roadkill.

View Midas Area in a larger map

Selected Reference:
Wallace, A.R., 1993, Geologic map of the Snowstorm Mountains and vicinity, Elko and Humboldt Counties, Nevada: U.S. Geological Survey, Miscellaneous Investigations Series Map I-2394, scale 1:50000.

Thursday, August 23, 2012

Highways 8, 8A, and 8B

While already busy on the Tuscarora Loop series, which I hope won't be posted in too sporadic a fashion, I noticed that I'm practically living on old Highway 8A!! (How did I not notice this before now??)

Nevada state highways 8, 8A, and 8B used to be a semi-contiguous set of routes that ran from Tonopah to Austin (8A, now S.R. 376), Austin to Battle Mountain (8A, now S.R. 305), Winnemucca to McDermitt (8, now U.S. 95), Winnemucca to Paradise in Paradise Valley (8B, now S.R. 290), and all across northwest Nevada: from between Paradise Hill and Orovada to Denio on what is now S.R. 140, part of the Winnemucca-to-the-Sea Highway, and then from Denio or Denio Junction to the California state line near Vya, on what is partly S.R. 140 and mostly an unmarked but possibly still locally signed portion of 8A. This latter portion of 8A, located almost entirely in northern Washoe County, has not been numbered on state roadmaps since 1981.
1929 Nevada Highway Map,
with the first appearance of S.R. 8 and S.R. 8A.
1932 NV Highway Map,
with the first appearance of S.R. 8B.

Highway 8B is shown with varying lengths, sometimes not making it quite to the town of Paradise, sometimes making it to Paradise, and sometimes making it some undefined or variable short distance beyond Paradise.
1939 NV Highway Map,
the last year S.R. 8 was shown for what is now U.S. 95.
1967 NV Highway Map,
the last year S.R. 8A was shown for what is now S.R. 140.
1978-79 NV Highway Map,
showing old and new numbers for 8A, 8B, and 140.
1980-81 NV Highway Map, showing old and new numbers for
8A and 8B, but S.R. 140 is back to it's usual self.
1982 NV Highway Map: all the old numbers of our favorite
roads are gone, replaced by the new ones.
2011-2012 Nevada Highway Map,
the current map.

As far as the maps go, rather than just the highways, a few things are noteworthy: at least one Indian reservation has shrunk over the years, according to these maps, and "DANGER" areas (military bases or withdrawals), which were shown as zero on the 1929 map, have increased over the years, including an increase in the Fallon area on the 2011-2012 map as compared to the the 1982 map.

Oh, and the last time Winnemucca Lake was shown on these highway maps (instead of Winnemucca Dry Lake), was in 1940, though elsewhere it is said to have dried up in the 1930's, more specifically, by 1938. The lake dried up as a result of the Newlands Reclamation Act of 1902, specifically the building of Derby Dam in 1905, which diverted water from the Truckee River into the drainage of the Carson (to irrigate Fernley and Fallon). Additionally, at some point after the lake dried up, Mud Lake Slough, the spillover to Winnemucca Lake from Pyramid Lake, was blocked, reportedly by Highway 34, now S.R. 447, an assertion confirmed rather obliquely here in Note 29, giving no timeframe for the action.

Links to all Historical Nevada Highway Maps.

Monday, August 20, 2012

Update from the Lake: Late Summer

A puff of smoke over a nearby mountain, early in the morning.
Fishing boat on the lake with more smoke from nearby forest fires.
One of our few blooming daisies in the early morning.

(The drip line has been off this year: we've been too busy and too far away to garden.)
Later: Out for a walk.
A parent Osprey exhorts one of two juveniles, still in the nest, to fly, already.

(At least that's what we think all of the screeching and hullabaloo was about, and maybe it was spurred on by the near constant smell of smoke in the air?)
Mama or papa Osprey flies away from the treetop nest.
Midday: More smoke over the water.
Evening: A bright orange-red sunset.

Thursday, August 16, 2012

Pulpit Rock

MOH and I came upon Pulpit Rock from the east on our last tour through the Black Rock and Smoke Creek Deserts. I have some old photos lying around somewhere, maybe even some digital ones, but in case I couldn't find any, we pulled over on the side of the road so I could grab a few more. We once hiked up to the rock; I suspect the photos from that hike are on photographic paper in 4x6 mode, filed away in an archival box. (That reminds me: my project to digitize everything. Ha ha ha.)

The rock, placed in the pillar category by the U.S.G.S., has obviously been named for its shape. It's not far from the Nobles Trail (or Nobles' Trail), which passed through the Kamma Mountains not far to the south, so maybe the name originated with emigrants on the trail, but I've found little history about the rock, other than that it's considered sacred by more than one group of Native Americans. It's also been used as a nesting site for golden eagles, ferruginous hawks, and prairie falcons (p. 3-43, last link).

MSRMaps location; Google Maps street view.
Almost immediately upon pulling over, we noticed two large birds perched in an upper alcove of the rock formation, and at first we thought they were golden eagles.
I took some more pictures simply to identify the birds. This photo, when enlarged on my camera, made me wonder if the birds could be bald eagles, because the coloring seemed off for goldens.
Aha! The one flying away is a obviously a turkey vulture!
Now, only one bird is left!
We don't know if the alcove was being used for nesting by these birds, or if it was just a convenient perch to wait for roadkill dinner.

Monday, August 13, 2012

Sawtooth Dike

Backing up somewhat from Midas on the Tuscarora Loop, one of the first places of interest on the way to Tuscarora from the Golconda side — besides the Midas Trough itself, which the Midas Road goes through to get to the turnoff to Midas — is a spectacular rhyolitic dike, Sawtooth dike (Zoback and Thompson, 1978), named after Sawtooth Spring (MSRMaps location).
Heading eastward into the Midas Trough on the Midas Road, the Owyhee Bluffs in the distance on the left.
Sawtooth dike running up the face of the Owyhee Bluffs.

This dark-colored, rhyolite dike is a feeder for a thick section of rhyolite flows that immediately underlie the rhyolite to rhyodacite volcanic rocks of Jake Creek Mountain, the latter of which cap this portion of Owyhee Bluffs. The older rhyolite flows fed by Sawtooth dike are, in aggregate, 10 to 400 m thick (more than 30 to more than 400 feet thick).
Air photo of Sawtooth dike (from MSRMaps).
A bit of geology: dike sections in turquoise, fault in blue.

Sawtooth dike is in two main sections, offset by a small left-lateral fault, with a small portion caught up along the fault. According to Zoback and Thompson (1978), the dike is a syntectonic intrusion, syntectonic with extension producing diking in the northern Nevada rift and with extension-related strike-slip faulting (a little more about the northern Nevada rift here). The south end of the dike is reportedly cut off by the north bounding fault of the Midas Trough (Rowan and Wetlaufer, 1973, per Zoback and Thompson, 1978).
Another view of the dike, from Zoback and Thompson (1978), used here as per GSA fair use policy. (Thanks, Andrew Alden!)

View Midas Area in a larger map

By the way, the entire road from its turnoff from I-80 or old Highway 40, through Golconda and out along what is now S.R. 789 to the current road usually called "the Midas Road," past Midas and out to Tuscarora, was known as S.R. 18 prior to the 1976 renumbering program (see this 1975 state roadmap). I'll be listing all non-40, non-I-80, non-789 roadside geology (and other) posts related to the Midas Road under the tag "18" as below.

A Few References:
Rowan, L. C., and Wetlaufer, P. H., 1973, Structural geologic analysis of Nevada using ERTS-1 images: A preliminary report, in Symposium on significant results obtained from the Earth Resources Technology Satelite-1, Vol. 1, Technical representations, Sec. A: Natl. Aeronautics and Space Adm. Paper G-20, p. 413-423.

Wallace, A.R., 1990, Geologic map of the Jake Creek Mountain quadrangle, Elko County, Nevada: U.S. Geological Survey, Geologic Quadrangle Map GQ-1672, scale 1:24000.

Zoback, M.L., and Thompson, G.A., 1978, Basin and Range rifting in northern Nevada: Clues from a mid-Miocene rift and its subsequent offsets: Geology, v. 6, no. 2, p. 111-116.

Friday, August 10, 2012

Tuscarora Loop

View Tuscarora Loop in a larger map

This is a Google Maps version of a road trip MOH and I made back in early June. The loop part of the trip begins in Golconda, goes north on the Getchell Mine Road, east on the Midas Road, past the turnoff to Midas, across a bridge at Rock Creek, past the turnoff to the Hollister Mine and Ivanhoe mercury-gold district (not shown), up Willow Creek to the Willow Creek Reservoir, over the Tuscarora Mountains to Tuscarora, down S.R. 226 (or Tuscarora Highway) to the Taylor Canyon Resort, beyond the resort to S.R. 225 (or Mountain City Highway), south to Elko, and west on I-80 to Golconda. As a loop, one can essentially start anywhere, not necessarily at the gas station in Winnemucca where we started. The Midas Road from the turnoff to Hollister and over the mountains to Tuscarora isn't always open in winter and can be muddy in spring to early summer.

Places shown:
1. gas station in Winnemucca
2. not quite downtown Golconda
3. turnoff from Getchell Mine Road to Midas Road
4. Sawtooth dike
5. folds in rhyolite
6. turnoff to Midas
7. Rock Creek
8. Willow Creek Reservoir
9. Tuscarora
10. Taylor Canyon Resort
11. Elko
12. Golconda underpass
13. gas station in Winnemucca

Besides the pinnacles and "Nodding Rock" in the Midas area, we'll be seeing some other sights from along this route in the coming days and weeks. The Midas Area map will be added to as needed.

View Midas Area in a larger map

Places shown:
1. turnoff to Midas
2. Midas
3. pinnacles
4. "Nodding Rock"

Wednesday, August 8, 2012

Nodding Rock

MOH and I spotted this rock formation in dark-colored volcanic rocks west of the town of Midas, NV, and called it Nodding Rock. The rock formation is part of a widespread group of rhyolite to rhyodacite flows, domes, and densely welded ash-flow tuffs (and rheomorphic tuffs?) that cap the Owyhee Bluffs and other nearby hills and plateaus of the Snowstorm Mountains near Midas: the volcanic rocks of Jake Creek Mountains, middle or upper middle Miocene in age.
General location (MSRMaps): the ridgeline about 1 mile west of Midas, south of hill 7230 and just north of the change in map coverage.

A Few References:
Wallace, A.R., 1990, Geologic map of the Jake Creek Mountain quadrangle, Elko County, Nevada: U.S. Geological Survey, Geologic Quadrangle Map GQ-1672, scale 1:24000.

Wallace, A.R., 1993, Geologic map of the Snowstorm Mountains and vicinity, Elko and Humboldt Counties, Nevada: U.S. Geological Survey, Miscellaneous Investigations Series Map I-2394, scale 1:50000.

Monday, August 6, 2012

Smoke in the Black Rock & Smoke Creek Deserts

Smoke over the Black Rock Desert, as seen from the east on the Jungo Road. Smoke is probably from the Salt Fire north of Redding.
Smoke over the Smoke Creek Desert, as seen from the southwest part of the Black Rock Desert looking toward Gerlach. Smoke is from the Chips fire near Belden and Caribou, CA, and the Peak fire in the mountains southwest of Milford, CA.
Smoke over the Black Rock Desert, as seen from Coyote Spring Dune (MSRMaps location, Google Maps location), looking east toward Trego Hot Springs.
Smoke over the Smoke Creek Desert southwest of Gerlach, as seen from Coyote Spring Dune. Newish jeep for scale.
Mirage on the Black Rock Desert, looking southwest toward Gerlach, the green patch or oasis in the middle ground, and at smoke beyond the peaks of the Fox Range in the background.
Smoke over the southern Smoke Creek Desert, looking south from a point on the Smoke Creek Desert Road, about four miles nearly due south of the mouth of Five Springs Canyon and about four miles southeast of Granite Spring. The darker hills on the left are in the Fox Range near Reynard siding; the lighter hills behind them are in the Fox Range near Wild Horse, Pole, and Rough Canyons.
Another shot from the same angle, with a thin mirage on the desert (click to enlarge). The farther pale blue hills beyond the ones near Wild Horse Canyon, et al, include low hills near Sano siding and Emerson Pass, the Terraced Hills just north of Pyramid Lake, and the Virginia Mountains on the west side of Pyramid Lake.

Photos are from 3Aug2012.