Occam's Razor is a logical principle, which can be mathematically demonstrated, that the 'simplest' of two competing explanations is usually the correct one. Note that in this context, 'simplest' is defined as 'the explanation requiring the fewest new assumptions'. Natural philosophers given to waxing metaphysical may find this discussion of Occam's Razor entertaining!
"But this could have come down the Toutle River", said the geologist, examining my prize chunk of multi-hundred-million-year-old brown mudstone, glacier-gouged and fresh from the quarry that morning.
Geologists. Gotta love 'em. At any convention of skeptics, geologist make us engineers look like a wild-eyed rabble of windmill-tilters. And that's a tip of the hat to y'all, geo-guys and gals!
Attending the Seattle-area IAFI Chapter meeting last week to introduce myself and some preliminary findings, I began to understand that communicating the 'context' in which these samples were found was of equal if not greater importance to obtaining and classifying the actual samples themselves.
Geologists. Gotta love 'em. At any convention of skeptics, geologist make us engineers look like a wild-eyed rabble of windmill-tilters. And that's a tip of the hat to y'all, geo-guys and gals!
Attending the Seattle-area IAFI Chapter meeting last week to introduce myself and some preliminary findings, I began to understand that communicating the 'context' in which these samples were found was of equal if not greater importance to obtaining and classifying the actual samples themselves.
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After all, should anyone be surprised to find this assortment along a river bank somewhere in the Canadian Rockies? Not at all. It was evident that I needed to better communicate the complete picture of what is truly remarkable about this collection to convincingly claim that 'glacial-ice rafting' is the most reasonable explanation.
Listed here are some noteworthy aspects of the context in which these erratic samples were found:
- Location: Not in a river wash, but near the top of a saddle between two watersheds
- Elevation: At an elevation that local rivers find difficult to access
- Proximity: In close 'hydraulic proximity' to a known Missoula Floods path
- Lithology: Erratics collected are indigenous to the Canadian Rocky Mountains, and many are relatively rare, if not unknown, locally
- Stratigraphy: Fractured erratics are dispersed throughout all layers of deposited clay
- In Absentia: Conspicuously absent from the deposited clay layers is by far the most ubiquitous local rock of all, basalt
Each of these aspects will now be discussed in more detail. No one item stands alone as 'proof positive' evidence, but taken collectively they form a strong basis for adding a singular, previously-unknown scientific assumption to explain the observed data: That 'some' exceptional Missoula Floods were able to enter the Chehalis watershed.
Location
By studying the image below, it is easy to see something that is fairly intuitive to anyone who has either worked on or recreated upon rivers for any length of time -- namely, that natural rivers are averse to running down the top of a ridge line. Man-made canals of course can be made to do so, but a fundamental law of statistical mechanics called entropy simply does not allow for this to occur in nature to any practical extent.
The ridge line in the image below runs from right to left, and the 'low point' is flagged as the 'Chehalis Saddle @132m'. East, to the right, is Mt. Rainier and the Cascade Range. West, to the left, are the scraggly weather-worn remnants of what passes for the Coast Range in these parts, called the Willipa Hills.
The ridge line in the image below runs from right to left, and the 'low point' is flagged as the 'Chehalis Saddle @132m'. East, to the right, is Mt. Rainier and the Cascade Range. West, to the left, are the scraggly weather-worn remnants of what passes for the Coast Range in these parts, called the Willipa Hills.
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| Fig. 2: Overview of Goods Quarry hydraulic relationships. View in Google Earth |
Both of the major rivers in this image originate from the glaciers of Mt. Rainier, and initially run more or less westward. In this field of view, the Chehalis River is beginning to break north, and the Cowlitz River beginning to break south.
The closest approach of the Cowlitz is about 14km to Chehalis Saddle, and the closest approach of the Chehalis is about 8km. There is no discernible evidence that any abandoned westerly-flowing stream-bed of either was ever any closer, within the relevant time-frame. Such streams would be called upon to deliver rocks from source formations on Mt. Rainier to provide local accounting for the suspected erratics.
Further, there is no discernible evidence of any perennial easterly-flowing stream-bed originating in the Willipa Hills approaching the Chehalis Saddle, within the relevant time-frame. Such a stream would be called upon to account for the great quantities of clay, ostensibly delivered from the "in-situ weathered basalt" clay deposits evident at higher elevations locally in the Willipa Hills. These local Willipa Hills clay deposits are explored in the Trailing a Whopper [currently in work] section of this report.
Elevation
At closest approach, the Cowlitz River is 100 meters below and 14km southeast of the Chehalis Saddle. At closest approach, the Chehalis River is 69 meters below and 8km northwest of the Chehalis Saddle.
Given their wide, capacious outwash valleys, it seems implausible that either of these rivers could have affected the others watershed in a meaningful way via the Chehalis Saddle, within the relevant time-frame.
Recognizing that both sampling sites thus far are located in the Chehalis watershed, and to verify that the Goods Formation is essentially uniform across the saddle, samples will be collected from Goods Quarry #1 and some other representative sites in the Cowlitz watershed before the final draft of this report is complete.
Given their wide, capacious outwash valleys, it seems implausible that either of these rivers could have affected the others watershed in a meaningful way via the Chehalis Saddle, within the relevant time-frame.
Recognizing that both sampling sites thus far are located in the Chehalis watershed, and to verify that the Goods Formation is essentially uniform across the saddle, samples will be collected from Goods Quarry #1 and some other representative sites in the Cowlitz watershed before the final draft of this report is complete.
Proximity
The Cowlitz River is a tributary of the Columbia, and as such the Cowlitz watershed is hydraulically inseparable from that of the Columbia's. As discussed at length elsewhere in Elevation Profiles and The Cowlitz Slough [currently in-work] sections of this report, the minimum elevation separating the Cowlitz from the Chehalis watersheds is 132m, which appears to be within easy reach of some exceptional Missoula Floods.
Lithology
Lithology is essentially the defining characteristics of a rock or mineral. The sedimentary and metamorphic lithologies found in the Goods Formation are common in the Foreland, Omineca and Intermontane Belts of the Canadian Rocky Mountains. The Foreland Belt in particular is notable for a minimum 15km thick layer of multi-hundred-million year old sedimentary rocks. In US geology references, the term 'Belt Supergroup' is often used to refer to these and several other related belts collectively. The range of sedimentary structures preserved in the Belt Supergroup is striking, as demonstrated in the preceding link provided by the Digital Geology of Idaho online reference.
In contrast, the local Cascade Range is known to have some equivalently-ancient sedimentary formations, but both the range of structures and breadth of variation within structures is predictably limited. This statement holds true to an even greater degree when we focus on known formations local to the sampling sites, at elevations which may have ostensibly contributed to alluvial deposition of the samples.
In a nutshell, elevated local formations for many of the sampled lithologies are unknown: [specific list to follow, when sample cataloging is complete and lithology identifications developed to a higher confidence level; i.e. including microscopic evaluations]
In contrast, the local Cascade Range is known to have some equivalently-ancient sedimentary formations, but both the range of structures and breadth of variation within structures is predictably limited. This statement holds true to an even greater degree when we focus on known formations local to the sampling sites, at elevations which may have ostensibly contributed to alluvial deposition of the samples.
In a nutshell, elevated local formations for many of the sampled lithologies are unknown: [specific list to follow, when sample cataloging is complete and lithology identifications developed to a higher confidence level; i.e. including microscopic evaluations]
Stratigraphy
Stratigraphy is essentially the study of rock and sediment layering. At Goods Quarries, the strata from bedrock basalt to surface are few, and their composition essentially homogeneous with slight variation and two exceptions. Except for the layer of surface soil observed at both sites, and except for a layer of in-situ weathered basalt-turned-clay observed at Goods Quarry #3, erratics were observed throughout the clay strata, in some locations from surface to bedrock.
Three erratic-rich clay 'rhythmites' may be evident here, conjectured to contain variable concentrations of ultra-pulverized organic material, which accounts for the variation in color. If this initial engineering conjecture is supported by follow-up geological analysis, the layers containing higher concentrations of organic material will evidence more 'accelerated weathering', predictably resulting in the enhanced rusty-orange color observed in the upper and lower strata.
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Three erratic-rich clay 'rhythmites' may be evident here, conjectured to contain variable concentrations of ultra-pulverized organic material, which accounts for the variation in color. If this initial engineering conjecture is supported by follow-up geological analysis, the layers containing higher concentrations of organic material will evidence more 'accelerated weathering', predictably resulting in the enhanced rusty-orange color observed in the upper and lower strata.
In Abstentia
Conspicuously absent from the lithology of the erratics found in the clay layers is the most common local rock type, the omnipresent Columbia Basalt observed everywhere in the vicinity. The basalt bedrock evidenced in the photo above extends for untold kilometers in every direction. For a local river to have collected the unlikely assortment of lithologies found in the clay deposits, while selectively excluding basalt, is a conjecture that by inspection seems implausible.
Conclusion
As a summary of the A Working Hypothesis [currently in-work] section of this report, the engineer's preliminary evaluation of these findings is that a significant, previously-unrecognized Missoula Floods sedimentary clay deposit has been discovered at these sampling sites that likely extends between, and for an unknown extent, beyond them.
Summary Hypothesis
This formation has been duly named the 'Goods Formation' by its discoverer, one Brandon W. Nichols, Professional Engineer, of Seattle WA. The simplified hypothetical explanation for the high concentration of glacial erratics found in these deposits is as follows:
- That the sampling sites lay within or adjacent to a northerly-discharging spillway, which
- Funneled and concentrated a procession of erratic-laden ice rafts to these locations
- The water transported over the spillway contained a high concentration of ultra-pulverized mineral clays,
- Some of which settled here as the spillway altitude fell when the floodwaters receded
- Most of the erratics here fell from the ice rafts as they melted, while the ice rafts continued onward
- The balance of erratics are accounted for by those ice rafts trapped in the sediment as the spillway altitude fell when floodwaters receded
- That 'some' exceptional Missoula Floods entered the Chehalis watershed
Rebuttal to Locally-Derived Alluvium Conjecture
- There exists formations both known and unknown for all erratic lithologies on Mt. Rainier, since all known local Willipa Hills exposures are basalt
- A westward river once flowed from Mt. Rainier, delivering erratics to the sampling sites
- The westward river traversed the Chehalis Saddle, defying the law of entropy
- The westward river flowed so briefly that it did not leave a channel
- An eastward river flowed concurrently, delivering clay from the Willipa Hills
- The eastward river flowed so briefly that it did not leave a channel
- The westward river was able to selectively exclude basalt from the transport lithology
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