WatershedEvents

Ball and Socket

A few days ago, on a field trip to Frenchman Coulee, I was with a group of Ice Age Floods enthusiasts when we ran across a curious geological phenomenon – groups of bowl-shaped polygons, some as wide as six feet across and almost a foot deep. Here’s a little of the information I’ve been able to dig up on these formations; more to follow if/when I get a chance to return to the subject.

The earliest mention of the phenomenon I’ve found so far was by R. Mallet, an Englishman, in 1874. I haven’t yet found an online copy of the paper (Volcanic Energy: An attempt to develop its True Origin and Cosmical Relations), but whatever his theory might have been, it (and he) were severely bashed by one of Lyell’s buddies, George Poulett Scrope – Note on Mr. R. Mallet’s “Prismatic Structures of Basalt,” Monthly Journal of Geology V.12, Jan-Dec, 1875.

Re: https://books.google.com/books?id=MlpmAAAAcAAJ&pg=PA413&lpg=PA413&dq=%22cup-shaped%22+basalt+formations&source=bl&ots=QRxyZxYZ-u&sig=k6Hxf-mqjtuGiO1pToWZzNUsEug&hl=en&sa=X&ved=0ahUKEwii9L_Kwc_TAhWJKGMKHYJnAhAQ6AEIJzAA#v=onepage&q=%22cup-shaped%22%20basalt%20formations&f=false
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The next reference to pop up was to a paper by R. B. Sosman titled Types of prismatic structures in igneous rocks, Journal of Geology Vol. 24, No. 3, (April-May 1916). On page 229 of this paper, Sosman discusses cross-columnar fracturing, which sometimes produces a ball and socket situation in which the bottom of the upper portion of the column is convex, the lower portion concave. Paragraph 6.2 is of particular significance in this regard. (This fits in with the notion that the formations above were created when the Missoula Floods ripped off the upper portions of the columnar basalts that make up so much of the Frenchman Coulee area. See photo of Echo Basin below.)

Re: https://www.jstor.org/stable/pdf/30079357.pdf
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A 2004 GSA article by C. Schafer & S. Kattenhorn (Character and evolution of fractures in low-volume Pahoehoe lava flows in eastern Snake River Plain, Idaho) provides information on how flow characteristic and differences in cooling rates (external vs internal / top-down to bottom-up)impact the development of cross columnar fractures. According to this paper, the concave/convex relationship (ball and socket relationship) tends to be favored in flow materials produced by the CRBG*. Another aspect of this fracturing noted by the authors is that it takes place in areas immediately outside the viscus materials, rather than inside them.

Re: http://gsabulletin.gsapubs.org/content/116/3-4/322.full.pdf+html
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I have to leave this post unfinished for the time being. Yard chores are calling me. But one more note, a personal observation: while studying my photos of these curiosities, it occurred to me that the slope angles involved here remind me a great deal of the kind of cleavages you get when you break certain types of basalt – one side is invariably concave, the other convex. I think that might be a significant observation, but am not geologically versed enough to know for sure. More on all this later;  meanwhile, comments, observations, and additional references would all be greatly appreciated.
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*The earliest mention of this ball-in-socket phenomenon I’ve found was in the 1875 reference mentioned above. That discussion focused on the basalts in the Giant’s Causeway in Ireland. Does this mean the Grand Ronde Flood Basalt Group in Washington/Oregon/Idaho is somehow related to those from which the Giant’s Causeway’s spectacular columnar basalts originated?

 

Note: Echo Basin. If you double click on this photo, it should open to a larger size. Then look for the rock climbers in the upper right quadrant. Before the floods tore through this area, an entire assemblage of colonnades extended above the high ground shown here.

Chum Salmon and the Weathering Process

Chum salmon contending for position over a spawning female (obscured by wave action photo left)

As I've written several times previously, each November chum salmon spawn in a small ephemeral stream not more than a quarter mile from our front door. Beatty Creek it's called, and I have loved it since the first time I laid eyes on it. This creek differs in almost every respect from Fanno Creek, particularly with regard to its bottom. The waters of Beatty Creek flow over deep beds of well sorted gravel; those of Fanno Creek flow over a bottom that is almost entirely composed of an exceedingly fine mud. 

Ironically, these creeks share a common ancestor: the Fraser Glaciation that invaded Washington State during the last glacial maximum. Fanno Creek's geological history is tied to the Purcell Lobe of that glaciation and its relationship to the great Missoula Floods that took place 16-12,000 years ago. The creek lies in the Tualatin Basin, a deep bowl of land in northwest Oregon. The Missoula Floods visited this basin at least once, leaving behind vast quantities of debris, including millions of tons of loess. The muddy bottom of Fanno Creek is directly attributable to that great abundance of that material. 

Beatty Creek, on the other hand, owes its salmon-friendly, gravely bottom to the Puget Lobe of the same glaciation. As that monstrous body of ice plowed through the Puget Sound, it carried with it enormous quantities of mineral-rich rocks it had literally ripped out of the mountains of British Columbia and Washington. When the glacier retreated, around 12,500 years ago, it left behind great piles of rocky debris, which in turn were washed and worn by glacial meltwater and all the other agents of the weathering process. The deep glacial drift that covers the lowlands of the Puget Sound are one of the artifacts of that weathering process. 

Great things happen when the rains of October and November flow through the ancient gravels of the Beatty Creek watershed. 

 

Drumheller Channels

Daughter Erica surveys the Drumheller Channels from a ledge overlooking Black Lake.

The view is to the northeast; but if you did a 360 here, it would look pretty much the same in any direction. The bones of this vast plain came into being sometime between 16.5 and 13.5 million years ago, when the flood basalts of the Columbia River Basalt Province pooled here, then begin to solidify. How long it took the completely sterile surface to completely heal in this particular area is hard to say, but it may have been thousands of years. Then as now, the prevailing winds were from the southwest. With every passage of the wind, a thin layer of loess was put down over the mineral-rich, rapidly decaying basalt. The layers ultimately accumulated to great depths - in some areas the soil was well over 200 feet deep. The closest land-borne colonizers were at least 90 miles away from here; the wind-borne plants and critters would have had to travel even further. 

The CRBG wasn't the only cataclysm to pass over this land in geologically recent times. Flood waters from glacial Lake Missoula poured through here around 13,500 years ago. The floodwaters were 10 to 12 miles wide, 200-400 feet deep, and moving at around 65 miles an hour. What you see in this location today are the ripped up remains of the CRBG basalts themselves. The vast and fertile prairie that once covered those basalts was completely stripped away and carried south towards the Columbia River. Once the flood had torn off the 200-400 feet of loose material covering the basalt, it went after the bedrock itself, literally plucking up great chunks and bearing them away as well.

J Harlen Bretz, the geologist who first recognized that the Scablands resulted from a flood of nearly unimaginable proportions, had this to say about this particular place:

“Drumheller is the most spectacular tract of butte-and basin scabland on the plateau. It is an almost unbelievable labyrinth of anastamosing [braided] channels, rock basins, and small abandoned cataracts”. 

The viewpoint above is on the southwest corner of the channeled area. I'd like to think Bretz once stood on these very rocks, and maybe someday I'll be able to find out if that is true.

I  was curious about the Drumheller name for this area, having already heard about the town of Drumheller in Alberta, Canada. After a little research (nothing exhaustive) I put my money on Daniel Drumheller, who settled in these parts around 1880. Looking for confirmation, I contacted the US Fish and Wildlife Service to see what they could tell me:

 No idea.  Washington State Place Names offers nothing.

We're going to keep looking.  I've reached out to the National Park Service, who administers the NNL program, and Laurie is going to look in the files.  If she finds anything, she'll let you know.  However, it just might be one of those things that can never be tracked down -- the person generating the application puts in a name, for reasons known only to that person, and that reason goes to the dustbin of obscure history with the person.  Or the place was named decades earlier by a local who, once again, is the only person who knows why he/she started calling the place by that name.

Dan (USFWS)

I'm focusing my research efforts in so many directions right now, I can't afford to pursue this curiosity any further, at least for the time being. But something tells me I will be passing through both this country and this little place-name mystery again, before I conclude my work on Bretz's wonderful story.