'Lithology' is essentially the defining characteristics of rocks and minerals, and 'Stratigraphy' is essentially the study of rock and sediment layering. As engineers seek to answer questions with the Laws of Thermodynamics, geologists seek answers in the fundamental truths of Lithology and Stratigraphy.
While this may seem like just two professional examples of Maslow's Law of the Instrument, in practical application the study of Root Cause Analysis shows that independent lines of reasoning with alternate bases of assumptions, both arriving at the same conclusion, provides a much higher level of statistical confidence in the results than either line of reasoning alone.
Geologists are a skeptical lot. And I can certainly appreciate why: When your profession is the gatekeeper for the Earth's natural history, one needs to be consistently vigilant in response to those who seek colorful revisions in accordance to their own personal agenda. And when your professional expertise includes superbly-honed rock and mineral identification skills, it is only natural to look for fundamental truths framed by question of lithology.
So while I may be 95% certain of my conclusions with respect to the origin of the Goods Formation, based on an engineering prediction of the required hydraulics subsequently supported by field data, and 95% certainty is a 'green light' criteria for many engineering and business decisions, for a respected geologist to support a revision to the Earth's natural history proposed by another profession, 95% just isn't good enough. And here again I can appreciate why: Because the last thing you might do in your professional geology career is defend some engineer's tilted windmill in front of a roomful of skeptical colleagues.
Thus one of the geologist for this research effort has set the following criteria for 99.9% certainty with respect to the Goods Formation, framed in terms of lithology: Locate several glacial erratics constituted primarily of the sedimentary metamorphic mineral known as 'argillite', similar in composition to this 30-ton specimen found at Erratic State Park in Oregon.
Now that I know what we're looking for, given these excellent detailed photos courtesy of the Geological Survey of Canada and the extensive glacial erratic content of the Goods Formation, I am 95% certain that it is simply a matter of time and effort, ranging from a few days to a few months, before we find them.
If by chance we don't find argillite after a reasonable effort, then we'll need to deduce another other way to elevate the geological confidence level to 99.9% for some exceptional Missoula Floods entering the Chehalis watershed. Because from an engineering confidence level of 95%, it is pretty clear where the kinetic energy and unaccountable materials came from that helped create Mima Mounds!
Chehalis Spillway from Mima Mounds
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