5 months ago
Collected yesterday from Kevin member of Marias Formation, near Loma Montana. I have been exploring a strata of sandy shale that is about 10 to 12 CM and is about 6 feet from the top of the Kevin rocks. Above the Kevin shale is glacial till. The explored strata rest on about 8 feet of dark grey bentonite shale. The lower bed of shale is nearly void of fossils. The layer I am exploring is rich in baculites and scaphites. Picture:This is assemblages of cretaceous age baculites. Wedged into the baculites is a piece of wood. Notice the knot where there was once a branch. Then there are these scales. The scales appear to be clams. Near the lower edge is part of an immature scaphite a type of ammonite.My take away, based on how the baculites and wood are piled on top of each other this rock was once part of coastal tidal shallows or a lagoon on the edge of the Western Interior Seaway. It is unlikely to fine wood in deeper water.