Travel Tuesday: Cliff near Summer Lake, Oregon

This cliff of black and white volcanic rocks is easily viewed from the Summer Lake, OR, rest stop, and from points north on Oregon Route 31, the Outback Scenic Byway. If anyone has any info about the geology of this cliff, please comment! What I see is a dark-colored mass of mafic or intermediate ash-fall material overlain by some layers of white, probably felsic, air-fall tuff, the deposition of which was interrupted by a basalt flow toward the left, so that some of the older whitish tuff layers are below the basalt flow, and some are above the basalt flow. Just a guess, however.

Google Maps: Summer Lake is the junction in the southeast, cliff is the white area in the northwest.
Detail of part of the cliff, showing some hoodoos.

This is the part of Oregon covered by Andrew Alden's recent post and photo gallery about the Oregon Outback. I've personally driven by here many times, usually in late July; this picture is from Day 8 of our recent Oregon trip (Day 7: volcano observatory, rock garden, Smith Rock).
I've never made it to the annual Paisley Mosquito Festival. Have always wondered ... have never stopped ... and have always keep my windows closed!

Trip report to be continued...

A Friday Field Update

...on a Saturday evening.

As many of you may have guessed, and as some of you may know, I've recently started working a fairly intense schedule and have been unable to do much of anything online without detracting from my sleep time. The schedule includes the 10-hour days that are usually expected of field geologists (in mineral exploration, at least), and it currently includes an unspecified length of time. One likely scenario would be to work about 20 days and then to take about 10 days off. I described a few typical schedules a couple years ago, though I didn't describe several currently popular options, including the 4 and 3 or the 8 and 6. From the 8 and 6, one might extrapolate a schedule of 16 days on and 12 days off, but I haven't seen that in place anywhere. Anyway, the upshot is that I'm "in the field" — that is, I'm not working at home, and I'm not working in an office. One definition: the field is the everywhere that you do geology — whatever kind of geology you happen to do — and that geology is usually, although not always, done out there away from town and away from home.

This particular job is a little unusual in that I really don't know how long it will last: there is plenty of work to be done, but is there enough money to do it? In my experience, this has been a bit of a problem during the last couple years, at least for some exploration companies. I personally have been fortunate during my long career to work through some fairly flush times, and also to work through leaner times with companies that maintained a healthy exploration budget. No exploration = no mining down the line, so it's a good thing (IMO) for companies to maintain a healthy exploration budget.

Recently, many of the larger companies — the few existing majors in particular — have devoted a fair portion of their time and money toward buying already proven or nearly proven reserves, and they've dedicated the rest of their time and money toward exploring on site, an M.O. sometimes called "brownfields exploration." In the last several years, brownfields exploration has largely been conducted at the expense of stepping outside the mine area, outside the property, and — heaven forbid! — at the expense of actually doing some well conceived "greenfields" or even "grassroots" exploration. (That is not true, by any means, in all cases, and the trend may be changing.) So if you, as an exploration geologist, don't know exactly where you want to drill because you are thinking of stepping outside the box, you might not find anyone willing to fund the mapping and sampling necessary to go find or prove up the next big one. The next big one might well be what will keep the current operation going.

Disclaimer: I haven't yet devoted any of my own time or money to this type of exploration, either, though many of my career-long colleagues have.

Highway 50 Links

I'm getting ready to post a Highway 50 Series list, but first I want to post general links for Highway 50. Many of these are road and travel links with some geology and history thrown in. The book recommendations at the bottom go directly to Amazon.com. This is my first non-retroactive use of Affiliate links (I've added links like these to a few old posts.) The way these work is that I might get paid, but only if someone clicking through actually buys something, and only if they buy something within some certain period of time. Hopefully, this doesn't seem outrageous - I often link to Amazon.com for books I talk about. These are all books I own, books I would recommend to anyone traveling Highway 50 in Nevada (the books at the bottom).

Some General Travel and Highway Links:
Experience the old west in Pony Express Territory, Nevada - Pony Express Territory

The Official Hwy 50 Survival Guide: Loneliest Road in America - TravelNevada.com

US 50 - The Loneliest Road in Nevada - CmdrMark dot Com

U.S. Highway 50 - Nevada - AARoads

U.S. Route 50 in Nevada - Wikipedia

U.S. Route 50 in Nevada - Answers.com (similar to Wikipedia, possibly more references)

US50 -- Nevada - US50 Coast to Coast

Nevada's Highway 50 - VIA Magazine, California State Automobile Association

The Lincoln Highway Association

History and Geology Links:

Captain James Hervey Simpson and Highway 50 - The Online Nevada Encyclopedia

Geology of Nevada; a discussion to accompany the Geologic map of Nevada (USGS): Stewart (1980), NBMG Special Publication 4 (link to NBMG sales info).

Books I Own and Recommend:
Geology of the Great Basin

Traveling America's Loneliest Road

Sagebrush Country

Touring California and Nevada Hot Springs

Hot Springs of Nevada

Oregon Trip Day 7: A Volcano Observatory

Photo from Windy Point: I'm standing next to 50,000 year old basaltic andesite from Black Crater (foreground, age approximate), looking across a 2,900-year-old basaltic andesite flow from Little Belknap (dark flows beyond the foreground trees), at the snow-capped peak of the 300,000- to 35,000-year-old Mt. Jefferson stratovolcano (Windy Point location, MSRMaps).

(If you don't know what observatory I'm speaking of, then you need to read on — and then you need to go there: you go down there — I mean, up there.)
Our third stop on the seventh day (after the rock garden stop) was in the town of Sisters, Oregon, where we had lunch indoors, and ice cream outdoors. The clouds were threatening when we arrived. They had cleared some by the time we left, but had regrouped before our fourth stop...
...at the Dee-Wright Observatory on top of McKenzie Pass (Google Maps). That's a view of Black Crater behind the sign — it's a partly glaciated shield volcano that extruded basaltic andesite flows about 50,000 years ago (see Cashman et al, 2009*).
At Dee Wright, you either climb steep stairs made of basalt (or basaltic andesite) or you walk a paved, gentle incline.
More than half way up, you come to a circular room with windows looking off in several specific directions. Each window frames a particular volcano; this is Mt. Jefferson.
It's worth going all the way to the top of the observatory for the view, and also to see this bronze "peak finder." According to long-time residents, this compass — which points to many but not all of the volcanoes visible from the top — has had to be replaced more than once. If you read the arrow in front of the snow-covered mountain on the horizon, you'll see that it's pointing to the North Sister, 6.6 miles distant, 10,094 feet elevation (according to the bronze plaque; according to the Dee Wright Observatory page at the CVO , the elevation is 10,085 feet). The Middle Sister, youngest of the three, is just right of the North Sister; Little Brother (the oldest) is on the right edge of the photo.
The Dee Wright Observatory is built on basaltic andesite flows that erupted from the base of Yapoah Crater, a 2,000 year B.P. cinder cone on the north flank of the North Sister (Cashman et al, 2009). The cone is visible but hard to point out from this angle.
Off to the northeast, the light brown volcano on the left is Belknap Crater, a basaltic andesite to andesite shield volcano that erupted 2,635 to 1,500 years B.P. Little Belknap is the dark point right of Belknap near the right edge of the photo. It erupted basaltic andesite about 2,900 years B.P. (these dates are from Cashman et al, 2009). The dark flows in the distance, behind a narrow swath of trees, are from Little Belknap; they flowed around a patch of older volcanic material (green area roughly in the center), forming what is called a kipuka (as seen in Cashman et al, 2009; USGS definition).

UPDATE: Read more about kipukas at Geotripper, who is currently in Hawai'i!
On the way down, a flock of small brownish birds with yellow colorings — possibly pine siskins — were hanging out amongst the basaltic flow rock.
If you drive a little ways to the west, you can look up toward the North Sister along a treeless flow from Yapoah Crater, the relatively barren cinder cone that barely sticks up above the mostly tree-covered skyline on the left side of the photo. It appears to have a white patch of snow on it's north side. In this Google Street View, Yapoah Crater is just left of the centered tree.

And you already know what we did after the field trip: we went to the Terrebonne Depot, had a great meal and good ale.

Main References:
Cashman, K.V., Deligne, N.I., Gannett, M.W., Grant, G.G., and Jefferson, Anne*, 2009, Fire and Water: Volcanology, Geomorphology, and Hydrogeology of the Central Cascades and Adjacent Areas, Oregon: Geological Society of America, Field Guide 15 (field trip no. 409).




*Anne Jefferson, who blogs at Highly Allochthonous, sent me a copy of this field guide, which I used extensively during this portion of our road trip. Thanks, Anne!

USGS Cascades Volcano Observatory.

Trip report to be continued... not necessarily in a timely fashion.

Oregon Trip Day 7: The Petersen Rock Garden

For day seven's second stop, which naturally came after the first, we went to the Petersen Rock Garden, which is a couple miles west of Highway 97, about 6 miles southwest of Redmond, Oregon.

The rock garden is a little difficult to find if you're trying to get there the way we did, which was by looking for a sign on Highway 97 south of Redmond, then turning right, and then following more signs at turns on the back roads west of the highway. I don't know if the garden would have been any easier to find following signs from Highway 26 west out of Redmond and then south: the signs are old, several (all?) are right at the turns instead of conveniently before the turns, and many (all?) have faded. My mom, who had been there many years prior, managed to tell us which way we would turn prior to each turn using some suddenly manifested sense of direction. Usually it's my dad who doesn't need a map. Here's the location of the garden on Google Maps.
The Petersen Rock Garden is an interesting combination of cool green shade,
...lily-covered ponds,
...rocks, mostly from Oregon,
...and a museum with, you guessed it, more rocks (and minerals) from Oregon and elsewhere,
...including one of the largest thunderegg collection I've ever seen, ...and peacocks.

Trip report to be continued...