Reconstructing a Mid-Cretaceous Landscape from Paleosols in Western Canada

Clay coatings from a modern soil chronosequence: A tool for estimating the relative age of well-drained paleosols

“…Thus, thickness values were not quantified in this investigation. From this study, and several studies involving the micromorphologies of well-drained paleosols (White et al, 2000;Ufnar et al, 2001Ufnar et al, , 2004Ufnar et al, , 2005, it is interpreted that the modal percentage of clay cutans is a rapid, reliable, and easily-obtained estimate for the relative age of the well-drained phase of pedogenesis in a warm, humid Clay coatings are thin (10-30 μm in thickness), and discontinuous w/ diffuse extinction, and composed of moderately oriented clays; clay coatings have gradational boundaries with matrix, and are commonly fragmented and incorporated into the matrix Sphaerosiderites microcrystalline interior, and fibrous exterior, brown-orange, ferruginous rings (quasi-coatings) within nodules, minor pyrite inclusions. environments and paleoenvironment.…”

“…The paleosols were described following the same techniques described above, and the methods described in Ufnar et al (2001Ufnar et al ( , 2004Ufnar et al ( , 2005.…”

“…McCarthy and Plint, 1998;Ufnar et al, 2005). It would be particularly useful for sequence-and parasequence-bounding paleosols where the timing of nonmarine processes are very poorly constrained (White et al, 2005;Gröeke et al, 2006).…”

“…These paleosols all had a polygenetic history of soil development characterized by an early, welldrained phase followed by a later, poorly-drained hydromorphic phase (e.g. McCarthy and Plint, 1999;Ufnar et al, 2005). It was during the well-drained phases of pedogenesis that these paleosols accumulated illuvial clay.…”

A multi-disciplinary perspective on habitat preferences among dinosaurs in a Cretaceous Arctic greenhouse world, North Slope, Alaska (Prince Creek Formation: lower Maastrichtian)

“….6A; Brandlen, 2008; Fiorillo et al, 2010 a, b;Flaig et al, 2013), providing evidence for widespread clay illuviation and, in general, somewhat better drained conditions than downdip near the other bonebeds(Fiorillo et al, 2010;McCarthy and Plint, 2003;Ufnar et al, 2005). Bioturbation is typically more intense, and Fe-and Mn-oxide features are also better developed in up-dip areas(Fiorillo et al, 2010), and the proportion of pedogenically derived illite is greater(Salazar Jaramillo et al, 2015).…”