Yeehow GeoMap-a-thon, Day 4

I don't have a particularly meaningful map to post today. Have been mired in correcting imported linework from the vr...topology issues. However, did spend a lot of time mapping in the landslides coming off of Bogus Rim and had a good online chat with Spud about some contentious mapping calls of mine. Worthy of a group discussion in the field for sure.

Using the vr is instructive, but it is most useful in topographically complex areas. Many of the lines I added were redundant with respect to prior flat mapping and field mapping. By placing the vr lines on high-res imagery using ArcExplorer (get it now) also proved just how useful it would be to be able to directly edit arc-ish linework. The screen shot below is what my computer looked like most of the day. The area is the large foundering slab of Qbw above Dogleg. Check the killer perspective on the right vs. the flat map perspective on the left. Note also that the overprinted lines on the left are the imported vr lines and the prior flat mapping lines. My goal is to now find out why I can't place vectors on precisely georeferenced images draped on topography.

Check out ArcExplorer. It is free. Not as good as Google Earth, but possibly more functional? At least it has the high-res imagery for our area. Lastly, it cannot adequately render the gorge because of the extreme relief and some bad orthorectification inthe NAIP data. Turns out that careful orthorecitification of high-res photo scans in the vr has some (but less) trouble here. If we can drape images on the LiDAR and map on that....

Yeehow GeoMap-a-thon Day 3-D

No map to post today, instead here is a shot of me totally geeked-out (electric glasses, mp3 player, Blackberry) working away on the map. The 3-D mapping is great, but it takes some serious time. Since it allows you to check the elevation of any point in the image, it allows for some checks of in situ vs. landslide strat...this has led to some significant reinterpretations of the suite of landslides off of Bogus Rim...lots to talk about. Lots more in situ rock there than appears at first, second, and third glance.

Yeehow GeoMap-a-Thon day 2

Good progress today despite interminable interruptions. Heather (NBMG Yeehow in training...YIT) set up Rome Valley on the VR today...the 3-D computer mapping device. I will get to mapping that in more detail tomorrow AM. 3-D will help immensely in that reach. Have relied on much of Cooper's mapping to get the lava flow extents. Some refinement added. Some questions about where some begin and where some end still remain. Anyway, here it is:

A big week for the Yeehow GeoMap

Howdy. Here is a 1:200k version of the map as it stands at the end of the day today. I will commit to updating this image via blog entry each day through Friday as a form of personal motivation. Many of the color bleeds will go away with some topology corrections and some additional lines. Yes. I did start mapping the Q lava flows to their sources. At some point, I need a little help from Cooper with this. Note the major league lava-water interface in the Danner area (east of Arock)...yowza. Looks like a good side trip for Yeehows. Totally cool and unexpected (by me, at least). Sometimes it is good to look beyond the map area, no?

Incision of Hell's Canyon

Hi again,

If you are not up on the evolution of the Western Snake River Plain (WSRP) and the timing of the cutting of Hell's Canyon in relation to the Owyhee intra-canyon lava flows then consider reading a paper by BSU Emeritus geomorphology professor Spencer Wood and his colleague Drew Clemens, "Geologic and Tectonic history of the Western Snake River Plain, Idaho and Oregon" Find it at:
http://earth.boisestate.edu/home/swood/WOODCLEM-2002.PDF
Among other things, the paper discusses where and when Lake Idaho existed and how and when Hell's Canyon was cut. It refers to work done by Kurt Otherberg, who Jim had mentioned before in the context of Hell's Canyon.
-Spud

Paleoclimate of northern Great Basin and Owyhee area

Hi folks,

Two years ago I asked Peter Wigand for some direction in
searching for papers that might help us understand the
paleoclimate (and therefore perhaps river discharge and
stream power) of the Owyhee River basin.  He replied to
me but I never was able to track down all the papers he
suggested.  I am providing his suggestions here in the
hopes that we can improve our understanding of what the
Owyhee River might have looked like during the existence
of the lava dams.  He said to start with the first one
which had an extensive bibliography that would
lead to some of the others.
-Spud




Wigand, P. E. and D. Rhode. 2002. Great Basin
Vegetation History and Aquatic Systems: The Last
150,000 years. Pp. 309-367. In Hershler, R., D. B.
Madsen and D. R. Currey (eds.), Great Basin Aquatic
Systems History. Smithsonian Contributions to Earth
Sciences 33. Smithsonian Institution Press,
Washington, D.C.

Mladen Zic, Robert M. Negrini, Peter E. Wigand. 2002.
Evidence of synchronous climate change across the
northern hemisphere between the north Atlantic and the
northwestern Great Basin, USA. Geology 30(7):635-638.

Cohen, A. S., M. Palacios, R. M. Negrini, P. E.
Wigand, and D. B. Erbes. 2000. A paleoclimate record
for the past 250,000 years from Summer Lake, Oregon,
U.S.A.: II. Sedimentology, paleontology, and
geochemistry. Journal of Paleolimnology 24
(2):151-182.

Negrini, R. M., D.l B. Erbes, K. Faber, A. M. Herrera,
A. P. Roberts, A. S. Cohen, P. E. Wigand, and Franklin
F. Foit, Jr. 2000. A paleoclimate record for the past
250,000 years from Summer Lake, Oregon, U.S.A.: I.
Chronology and magnetic proxies for lake level.
Journal of Paleolimnology 24 (2):125-149.

Mehringer, P.J., Jr. and P.E. Wigand. 1990. Comparison
of Late Holocene environments from woodrat middens and
pollen, Diamond Craters, Oregon. In Martin, P.S., J.
Betancourt and T.R. Van Devender (eds.), Fossil
Packrat Middens: The Last 40,000 Years of Biotic
Change. University of Arizona Press.

Wigand, P.E. 1987. Diamond Pond, Harney County,
Oregon: Vegetation history and water table in the
eastern Oregon desert. Great Basin Naturalist 47
(3):427-458.

OWY-19, river left outcrop of WC between Bogus Falls and Dogleg

Here are two photos--long overdue--that show the contact relations of the WC lava where I collected sample OWY-19. One shows the modern swale that has eroded around the WC lava that filled the paleo-swale. The other photo shows the nature of the contact between WC and lava flows within the Tertiary section: the WC lava sits on top of the Tertiary section there.
-Spud

Cascadian Pyroclastic Goodness

The results are in. Nick Foit's lab at WSU has analyzed some Owyhee tephra samples with a new probe. The delay in getting the data owes to the time it takes to set up such a device. Turns out that it was worth the wait. The tephra id's match Yeehow conventional wisdom in so much as they match the most likely candidates at each site.

I don't have time to work up anything fancy for this post (leaving for different field area in AM...not ready yet, but here is the dirt:

Mt. St Helens Set C, approximate age 47.2 ka found in lacustrine seds on river right and left above West Crater flow (image above is from sample on river right). These are the samples that we both related to OSL ages of approximately 20 ka. The occurrence of this tephra on both sides of the river and at disparate elevations is interesting and is evidence for sedimentation at two different levels here. One associated with the Owyhee, and one associated with the perched paleo Ryegrass Creek.

Mazama Tephra was found in auger holes in depressions on the Bogus Point landslide and on one of the Heaven's Gate landslides. The Trego Hot Springs tephra was also found deep in the core of the Bogus Point landslide sag. This bed (from Newberry Volcano, I believe) dates to approximately 23.2 ka.

We also found Mazama (6850 c14 yrs BP; ~7600 real years) tephra in an arroyo cut formed in a breached sag on a landslide on river left in Heavens Gate.


View Larger Map

Geologic Compilation Celebration

Today, I finally began to georectify O'Connor's field maps to cross-check against and augment my mapping. Using GlobalMapper this process takes only about 1 minute per map. Love that program. As expected, Jim's mapping is good. Take a bow. Our overlapping mapping only differs by refinement owing to more overland work and hi-res imagery. Of course, the man found some things I missed under both of those circumstances. Don't worry Cooper, your mapping is next. Will pay attention to your paleochannels on West Crater, relax.

While compiling Jim's compilations, I noticed a couple of intracanyon flow remnants in the gorge that I had forgotten about. They are labeled as Lambert (West Crater) but are most likely Clark's Butte given their elevation. I believe that the northernmost one is in the Tertiary section...but am not sure.

Any clarification / confirmation / elevation/ consternation that any Yeehow may have about these blobs would be appreciated. Photos would be super neato.

Reply to depocenter in middle of WC flow

Yes, the comment fcn on the blog seems to be out of order--this post is in regard to Dr. Jerque's post of WC in VR hindsight, etc. etc.

Dr. Jerque,

The area marked by a question mark on the image you posted could certainly contain sediment from the Owyhee River as the river flowed over the top of the WC lava. I have been there and was impressed by this expansive, low relief area made mostly of silts. I will review my notes at home tonight on the matter. I do recall also acknowledging that the area could easily be a depocenter for Bogus Creek. The road that you can see in the upper right corner of the image is built on a ~1.5-2 m high (man-made) berm (levee!!) that ensures all of Bogus Creek flows north rather than between some tumuli down to the low relief silty area as it clearly could do in the drop of a hat (or a March rain-on-frozen-ground event).

Yes, there are some large gravel/cobble bars along the lower reaches of Bogus Creek near the kipuka. If i recall correctly, these happen to be low enough in elevation and downstream enough to be within reach of overflows from the Owyhee River passing through the possible depocenter but also from other overflows further downstream. (Having said that, there are some sizable ephemeral channels that pour off the Bogus Rim directly to the east of the kipuka and these could contribute a lot of discharge in a large convective event or spring rain on snow.) It may be worth considering auguring this silty depocenter or digging some test pits there to understand the deposits or find some datable material.


And yes, there are several different lobes and inflationary flow fronts to the WC lava flow that wrap around Bogus Point and create some unique positive and negative relief. I looked at these in stereo many times and walked around on the ground there with an eye towards assessing the timing of these lava pulses and the potential interaction with the river. After a lot of back and forth, I continue to return to my original interpretation that there is only one lava flow in the area--the WC-- and that water flowed through a narrow gap between several tumuli far more upstream than the rounded boulders on the edge of the modern cliff of WC adjacent to Chalk Basin show. I am pretty sure that this nascent paleo channel is the upstream-most one shown on my maps of several years ago. Furthermore, there probably is a complex set of damming and overflow events because even though there is probably only one lava flow there, it probably made several surges or advances in its battle with the river and rising lake.

I sure wish I could have come to Bend!
-Spud

Ouch. I missed these... comment by Lisa

Lisa e-mailed a nice comment that I have placed on the blog for the record. I agree with her points. Something appears to be wrong with the commenting function in blogger...not with Lisa.

I recently re-read Howard et al.'s paper. The difference I see is that they stop short of going into detail about the impact of the lava dams on the geomorphic evolution of the canyon. Their paper provides a great basis of comparison for ours, but we can take ours much further with our more extensive dating, mapping and our possibly greater interest in the river canyon geomorphology. The Howard et al. paper was not that long, and mainly focused on the description of the lava flows and dams. We have more controls on incision rates through different lava flows at different times and places on the river, which I think will lead to interesting discussion.

I've sent away for a few more references to lava dams in the last couple of days. I'll circulate them when I get a chance to look them over. Quite a few on the Snake River, some in Canada, one in China.

Ouch. I missed these...

On my (not so) recent trip down the Grand Canyon, I had a lingering memory of Cassie suggesting that Keith Howard had been a little hard to convince as to the reality of lava dam failure and catastrophic flooding there, but that some of the field evidence finally convinced him. I had that lingering memory because I was weakly skeptical based on the lack of such evidence on the Owyhee, but was confused because I had read (and reviewed) a couple of her papers. Turned out that I really needed to see the stuff in person with a better backlog of personal observations. As I noted in a previous post, some of the flood evidence was (to me) hilariously clear and my skepticism was baseless for the most part.

Now that I have finally read Keith's Boise River lava dam paper, I can understand why he was skeptical given the striking parallels between the Boise River story and the Owyhee River story. (thanks to Lisa for sending the pdf). Moreover, the Howard and Fenton abstract (that, admittedly, I was not aware of) reads just like the thoughts I had in mind while thinking of the Owyhee while floating the Colorado. Some of the differences are profound.

Admission of guilt: I am truly embarrassed that I had not read the Howard et al. paper years ago, as it would have made it far easier and faster for me to understand the history of the Owyhee River. Oh well....As for the more recent abstract...no excuses there either.

We should really consider checking out the Boise River sites sometime.

LAVA DAMS COMPARED IN BOISE RIVER CANYON AND GRAND CANYON

HOWARD, Keith A., U.S. Geol Survey, Menlo Park, CA 94025, khoward@usgs.gov and FENTON, Cassandra R., U.S. Geol Survey, 1675 W. Anklam Rd, Tucson, AZ 85745 Pleistocene intracanyon basalt flows that dammed the Boise River, Idaho offer comparisons to those that dammed the more powerful Colorado River in Grand Canyon. In both canyons, olivine basalts erupted several times from vents near canyon rims, and flowed down steep canyon walls into the rivers and onto thick gravel beds. The multiple lava dams in Grand Canyon exhibit many stratigraphic complexities as compared to the simpler stratigraphic structure of the dams built on the Boise River, best exemplified by the Steamboat Rock Basalt and the Smith Prairie Basalt on the Boise River’s south fork. These two dams were each constructed to heights of 150 m from multiple flow units of basalt, which flowed tens of kilometers downstream while building lava deltas into the growing reservoirs on the dam’s upstream faces. Paleowater levels in the lava deltas, where lava flowed into rising reservoir waters behind the dams on the Boise River, are easily recognized as passage zones where topsets of subaerial pahoehoe pass abruptly downward into upstream-dipping foresets of pillows and hyaloclastite. Successive flow units entering a rising reservoir resulted in an asymmetric dam, much longer on the downstream face, and cored by massive subaerial basalt that interfingered upstream with a series of upstream-thickening wedges of pillow basalt. Grand Canyon lava dams also show evidence of upstream deltas where lava interacted with dammed water (described by Hamblin), but coarse hydroclastitc breccia dominates over pillows and foreset-bedded hyaloclastite; the deltaic structures are complex. Whereas several dams in the Grand Canyon failed catastrophically to produce outburst floods (described by Fenton and colleagues), the dams on the Boise River were incised gradually. Their long downstream lengths contributed stability. The long flows and abundant pillows relative to breccias suggest fluidity of the lavas, and suggest rates of eruption and lava flow that were high relative to the discharge of the river that they entered. The Colorado’s discharge is twenty times that of the Boise River South Fork.

Rocky Mountain (56th Annual) and Cordilleran (100th Annual) Joint Meeting (May 3–5, 2004)

Funny aside: at the meeting in Bend, I 'independently' developed a diagram for how we could graphically convey the last 1.8 my of the persistently interrupted incision history of the Owyhee. Much to my dismay, within minutes of touting the merits of my exmple figure, I was faced with a nearly exact example prepared by Howard et al. Lisa had the paper with her and I read it for the first time right then and there. In addition to the figure, many of the concepts presented in the paper were identical to discussions that we always have and were having that day. We then became concerned about how we could distinguish our study from theirs beyond just stating that it also happened somewhere else not very far away. I keep verging toward a discussion of the differences between landslide dams and lava dams with interesting counterpoints from the Colorado River and the Rio Grande.

West Crater flow (Qbw) in VR...old new insight

For the past few days, I have begun to compiling mapping using vr...the 3d visualization and digital mapping tool I mentioned last February--(http://yeehowcentral.blogspot.com/2008/02/virtual-reality-on-owyhee-almost.html). This has been very illuminating because it allows for me to zoom in to key areas in very clear 3D. Since I have already done so much flat-mapping (heads-up digitizing on NAIP images with stereopairs nearby) I have opted to focus on only key and slippery contacts or particularly complicated areas (i.e., the Hole in the Ground). I spent most of yesterday gawking at the Lambert Rocks, Bogus Point, and AM-PM areas.

In conjunction with recent field work (which was, in hindsight, inadequately thorough) I began to recall / notice that the low-relief area in the middle of Qbw is a likely depocenter for overflow related sedimentation by the Owyhee before it cut a canyon through the area. I traced rounded basalt gravel and sand through a sinuous tract across the lava flow toward that area but, alas, opted to head to my vehicle instead of trapsing (yet again) across the lava flow surface. It seems that all of my traverses on the flow have missed this key area. Anyone in the group happened to have been here?...Cooper?

Also, there are some fairly large gravel bars evident in parts of the Bogus Creek course near the large kipuka that are curious as well. Anyone been there?

Have also noticed that there are at least 3 conspicuous flow fronts of Qbw lobes in the Lambert area and am wondering if there is a more complex damming and overflow story there than it appears at first glance.

Saddle Butte Lake v. West Crater Lake

On my last field trip, I collected high precision GPS points on the highest evidence of overflow that I could find on each likely lava dam. In the case of the Saddle Butte lava dam (SBLD), there is evidence of shallow overflow over most of the extant dam crest...I had not realized this before. There are some photos of this in the recent album I posted. The highest overflow evidence was at 1044m (3425 ft). As for West Crater, the elevation of the first evidence for overflow (rounded basalt cobbles on the extant flow margin) is found at 1029 m (3375 ft)(*note that this is reported incorrectly in the figure caption). There is not nearly as clear a lava dam edifice here as there is at Saddle Butte, you may recall.

For what it is worth, the difference is more than expected or could be read from a topo map. As the figure indicates, a 15 m difference in depth has a locally significant effect on the extent of the lake. This is based, or course, on modern topography.

Thermodisappointmence commentary

Figure showing extent of possible lake above West Crater lava dam

Minding and (yes) chuckling about the technology gap, I have added some recent commentary from Yeehow Principals about the OSL results (see below).

I am leaning toward analytical or sample problems based in part on other OSL experiences, but admit that Jim's ideas hadn't occurred to me. I will mull them over. It is notable that the lake would have been fairly large and it may have taken sediment a long time to make it to the dam itself.

Kyle,
Can't blog on the site because I can't remember my user name or password or some such immense Luddite hurdle.
But my immediate thought (assuming that 22ka isn't just the standard OSL result) is that the lake (and its deposits) might owe to changing basin hydrologic characteristics rather than the timing of the blockage. Perhaps the blockage was not sealed sufficiently to form a lake until things got much wetter during the maximum of the last glacial. Or alternatively, significant sediment didn't accumulate until then in a lake that did date back to initial blockage. And recall that when the Alvord basin was full and spilling (at least for several hundred years) at some point loosely around this time during last glacial, there would have been a lot more water coming down the Owyhee from the expanded source area. This could be another twist on the story...
Perhaps the Crooked Creek flood triggered incision (would the terraces ages at Dog Leg jibe with that?).

I'll check on the tephra situation--I have many more samples that have been sitting there even longer. As I said when you sent them my way, you get what you pay for, and when you don't pay anything it's hard to whine.
...Jim

Yeehows,

Sorry, Kyle. I tried to post a comment to the blog, I really did. Same
luddite excuse as Jim. I seem to have set up multiple accounts with
multiple passwords and the matrix of possible matches is too much for me.

I've thought a lot about these OSL results. It's possible that the lowest
deposits are related to a landslide dam downstream, but highly unlikely
that the others are. The deposits on river left can be directly traced up
to the rim on top of the Saddle Butte. Any landslide that blocked the
river that high would have been close to the height of the West Crater dam
itself. I haven't been to the higher site on river left, but it looks like
it is on top of the WC lava itself. Jim's ideas are worth considering, but
my hunch is that something went wrong with the OSL dating itself. The
fine-grained samples we have to work with are not ideal. These ages are at
least 20,000 years younger than the youngest date on the West Crater flow,
and 40ka younger than our best estimate.

Caitlin has started reading up on OSL and the possible reasons behind
erroneous dates, especially those that are younger than the true age.
Next week, after we've discussed this at our Bend summit, I'll contact
Tammy with some specific questions about possible sources of problems with
these results and get her take on them. I have submitted additional OSL
samples from Sand Spring, behind Saddle Butte II flow (could also be
backed up from West Crater), 2 more samples from top and base and middle
of same WC section on river left, and one from sediments way up on rim
behind Bogus Rim flow. We'll see what comes of those. Should shed some
light on the issue, as some of them should be from older damming episodes.

Lisa

Back to the Bogus Lake

Here is a more detailed example of how large a lake dammed by the Bogus Rim lava would have been. This image assumes a dam at Iron Point with a crest elevation of 1200 meters. Made in a flash with GlobalMapper.

OSL Results....Thermodisappointmence?

Before my last field outing, I contacted the USU OSL lab about our samples. The good news: preliminary data are available. The bad news: wtf do they mean?

From: *Tammy Rittenour* <tammy.rittenour@usu.edu

tammy.rittenour@usu.edu>>
Date: Tue, Sep 30, 2008 at 3:03 PM
Subject: RE: Owyhee OSL?

To: Kyle House <pkhouse@gmail.com pkhouse@gmail.com>>

Kyle-

Ive attached the preliminary results from your Owyhee River samples.
They are about 75% complete at this moment. I am working on sending
them in for further processing because of some initial feldspar
contamination, but you should have the final results by the end of the
month.

The samples are all ~22-23ka, if they were taken from the same deposit,
then OSL seems to be working quite well.

Errors on the ages will go down when they are completed, but I dont
expect them to change much at all.

Good luck in the field,

Tammy

What do we make of this information? Well. We suspected that these lacustrine seds were related to damming by the West Crater flow. Given their distribution with respect to the upstream face of that flow this seems like a valid assumption. However, these ages are far younger than the likely age of the West Crater flow. That is a problem. Also, the samples cover a large range of elevation. I expected that there would possibly be a correlation between the elevation of the sample below the likely dam and its age. This is not the case. Check the figure below for a visual cross-check:This figure is a profile from the 10 m DEM data. The profile hits the four sample spots in the area. The geology is schematic (obviously) and hastily drawn (more obviouslyer).

Note the large elevation range of the three sample areas*. Each sample is denoted by a yellow circle (excpet the highest circle, that is a gravel deposit that wasn't sampled). We are still awaiting an identification of an obvious tephra bed that was sampled below the lowest OSL sample. Sent that (and all others) to WSU in early August....USGS has been sitting on it for over a year. If that comes back with a confident ID, then we will have some additional perspective on the OSL data. Any thoughts? Break down and add to the blog....

*I have wondered aloud on numerous occassions about the lowest one...possibly related to landslide dam? Its elevation is pretty low relative to the sublava paleochannel of Ryegrass Creek. The paleotopography implied by this (if related to West Crater) is pretty deep.

Topo Profiles in Study Area

I whipped up these images while revisiting the mapping in earnest today. These can be made in seconds using GlobalMapper. All offer some insights and are interesting to consider. We need to choose some key ones to illustrate with stratigraphy etc. If you lose your bearings, just click to go to the online album and check the map.

Geologic Froth: The Ultimate Digital Tool for Dummies and Luddites?

Geologic Froth: The Ultimate Digital Tool for Dummies and Luddites?

Precision GPS Data from Dogleg Bend

Last week, I spent some time collecting presumably high-precision GPS data with my new Trimble GeoXH unit. The first dataset that I have corrected is from Dogleg. Now we have some pretty robust numbers for incision rate calculations.

Grand Yeehow challenge. Someone out there break down and do the calculations. Post it to the blog and ruminate on it. My guess is that it will be sort of high.