I'll summarize the Pathlights claims instead of quoting verbatim, if that's alright with everyone here.
1. The Lewis Overthrust is way too big, hence it couldn't have happened. Hurrah for the good old argument from incredulity.
2. The Lewis Overthrust sits on top of undisturbed shale. Firstly, if this was true, it would raise problems for creationists as well! Limestone is a sedimentary rock made out of carbonate shells secreted by marine plankton; their particle sizes are much larger than the size of shale particles, and hence by any creationist mechanism, limestone should be deposited under shale - not on top of it! The creationists have an "out-of-order" problem of their own.
Well, there is a layer of highly fractured shale below the limestone, which is important - and which, by the by, creationists need to explain! However, the "shale" observed by Kulp was in fact fault gouge, composed of the finely-ground rock created by the movement, which is evidence for overthrusting, not against it! As for Lammerts' observation, some good sources have noted that his observation area was actually 200ft. above the fault, not at the fault itself; nevertheless, what he did observe was probably fault gouge if he had been looking at the right place.
3. There is no debris, therefore the Lewis Overthrust was not moved. Now, what would a creationist claim be without a quotemine? The Ross and Rozak quotation: "Such a slab moving over ground, as is now believed to have existed, should have scarred and broken the hills and have itself been broken to a greater or less extent, depending on local conditions. No evidence of either of these things has been found." sounds very different in context:
"The fracture zone that constitutes the Lewis overthrust was inclined upward in an east and northeast direction toward the surface (reference to figure omitted). If it had reached the surface, the forward end of the moving slab of rock above the fracture zone would have been abruptly freed from the resistances that had retarded its progress underground. Motion for a time might have been rapid, comparable with the motion which takes place at the broken ends of a slab of concrete that fails in a testing machine. The eastern end of the overthrust block might have rushed forward tumultuously. If such a thing had occurred, the rock at the eastern end of the moving mass, freed from the confinement from all sides that had formerly held it together, would have broken up; as it advanced over the surface of the ground the edge would have become a great pile of rubble. Masses of broken rock assigned such an origin have been found in front of overthrusts in other regions. The absence of rubble or breccia is among the compelling reasons that have forced the abandonment of the long-held idea that the Lewis overthrust emerged at the surface and moved over a plain near the front of the present mountains. Those who held that idea assumed that the ground surface was then level enough so that the overthrust slab could move over it readily. They also thought that the relatively flat surfaces that cap ridges east of the park are remnants of the nearly level topography over which the Lewis overthrust moved after it had reached the surface of the ground.
If the advancing slab of rock had been pushed out into the air, the confining pressures that held it together would have tended to be dissipated. Such a slab moving over ground as is now believed to have existed should have scarred and broken the hills and have itself been broken to a greater or less extent, depending on local conditions. No evidence of either of these things has been found. Further, the flat uplands are regarded now as remnants of a surface much younger than, and not directly related to, the overthrust." (Ross and Rezak, 1959,p. 424) [bold emphasis added; italics is the section quoted by Pathlights]
Basically, if the rocks moving in the Lewis Overthrust had emerged to the surface, the abrupt release of pressure would have essentially exploded (to abuse the term) the rock - and the kind of debris and breccia that would have created has not been observed. This means that the Lewis Overthrust happened subterraneanly, instead of over the surface of the ground; indeed, there is a lot of general evidence for massive deformation in the general area as I cited:
Parts of Glacier National Park and the adjacent areas are in the northern disturbed belt of Montana. The area east of the mountains contains thrust-faulted and folded Upper Cretaceous strata; it is equivalent to the Foothills structural province in southern Alberta. The area southeast of the park contains thrust-faulted and folded Jurassic and Cretaceous rocks, which locally are transected by northeasterly trending normal faults. These strataplunge northwest beneath the Lewis thrust plateand are not exposed in southern Alberta and British Columbia, except possibly in the Haig Brook and Cate Creek windows in the Lewis plate in British Columbia. The Lewis thrust plate is deformed by numerous folds and small normal and thrust faults. The major structure in the plate is a northwesterly trending, doubly plunging syncline. The largest normal fault is the Blacktail fault, which extends northwestward into British Columbia as the Flathead fault. West of it are other northwetsterly trending normal faults. The measured minimum easterly translation of the Lewis is 15 mi (24 km), but it may have moved at least 40 mi (64.4 km). The park is in a southwesterly trending, structurally low area that is bounded on the north and south by southwest-trending structures.
4. The Lewis Overthrust is way too hard to move, so it couldn't have been moved. Note that besides a completely out-of-the-blue citation by Terzighi, there is no other collateral proof given. What do scientists actually say?
"We have developed a simple model to evaluate the gravity gliding of nappes in sedimentary terranes. Three factors play a critical role in the model: (1) the ratio of horizontal to vertical stress, (2) the rate of fluid flow to the detachment horizon, and (3) the permeability of lithologies immediately above that horizon. If the ratio of horizontal to vertical stress is less than one, this ratio limits the maximum available pore pressure through hydrofracture. Existing in-situ stress measurements suggest that vertical hydrofracturing rather than gravity gliding might be the result of elevated pore pressures, unless a low-strength cap-rock exists. If the ratio exceeds one, a relatively simple equation relates the 'cap-rock' permeability and fluid flow necessary for gravity gliding. Effective cap-rock permeabilities less than 10-4 to 10-5 md are required for gravity gliding in a sedimentary basin. Based on available in-situ permeability measurements, only shales and evaporites could have sufficiently low permeabilities on a regional scale." (emphasis added)
... and guess what the Lewis Overthrust sits on? Shale!
5. Since we can tell you what layers the Lewis Overthrust contains, you should trust everything else we say about it. At least, that must be what their point is in listing all those layers, because it serves no other purpose than to undermine the creationist position. Argillite is a clay sediment much like shale, and limestone is limestone. According to the creationist position, limestone should be found beneath shale, since limestone is made of bigger particulates (assuming either can be deposited at all). Instead, we have alternating layers of argillite and limestone! How does a flood deposit that? What sort of local conditions can you postulate for that?
The conclusion: even if the creationist assessment of the Lewis Overthrust were correct, it would pose at least as much difficulty to a global Flood as it does to conventional geology, if not more. But the creationist assessment is wrong!
If a grinding layer shows one section of rock moved over the other, how is the overthrust evidence of fossils being laid own in the wrong order?
