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Evidence of Cretaceous Glaciation and its Impact on Dinosaurs
There is indirect evidence that a glaciation event existed during the
late Aptian-early Cenomanian [approximately 100 MA]. Here in eastern
Nebraska the event is recorded by a large-scale, unconformity-bounded
sequence of the lower Woodbury Member of the Dakota Sandstone [aka
"Muddy-Mowry Seaway" or "Muddy sandstone"]. An eustatic sea-level
mechanism lowered worldwide sea-levels by more than 25 m and that this
sea-level fall occurred in a rather short period of geologic time. A
glacioeustatic component is most likely to account for the observed
sea-level changes during the mid-Cretaceous “greenhouse” world. I'm not
aware of the existence of large-scale continental ice sheets. But, a
Southern Hemisphere polar ice sheet with limited extent and volume
compared to “icehouse” continental ice sheets, and global alpine
glaciers that were fed by wet climate cycles [a local condition which is
well documented during Dakota sedimentation] could account for sea-level
fluctuations that resulted in valley incision and subsequent filling.
Does anyone know of additional works on mid-Cretaceous glaciation and if
so what sort of impact would be found on dinosaur diversity and/or
Alley, N.F., and Frakes, L.A. 2003. First known Cretaceous Glaciation:
Livingston Tillite Member of the Cadna-owie Formation, South Australia.
Australian Journal of Earth Science. v. 50, p. 139-144.
Bornemann, Norris, Friedrich, Beckmann, Schouten, Sinninghe Damsté,
Vogel, Hofmann and Wagner.2008. "Isotopic Evidence for Glaciation During
the Cretaceous Supergreenhouse" Science Vol. 319 no. 5860 pp. 189-192
Gale, A.S., Hardenbol, J., Hathaway, B., Kennedy, W.J., Young, J.R., and
Phansalker, V. 2002. Global correlation of Cenomanian (Upper Cretaceous)
sequences: Evidence for Milankovitch control on sea level. Geology. v.
30, p. 291-294.
Haq, B.U., Hardenbol, J., and Vail, P.R. 1987. Chronology of Fluctuating
Sea Levels since the Triassic. Science. V. 235, n. 4793, p. 1156-1167.
Immenhauser, A. 2005. High-rate sea-level change during the Mesozoic:
New approaches to an old problem. Sedimentary Geology, Vol. 175, p.
Ludvigson, G.A., Gonzalez, L.A., Metzger, R.A., Witzke, B.J., Brenner,
R.L., Murillo, A.P., White, T.S. 1998. Meteoric sphaerosiderite lines
and their use for paleohydrology and paleoclimatology. Geology, v. 26,
n. 11, p. 1039-1042.
Miller, K.G., Sugarman, P.J., Browning, J.B., Kominz, M.A., Hernandez,
J.C., Olsson, R.K., Wright, J.D., Feigenson, M.D., and Van Sickel, W.
2003. Late Cretaceous chronology of large, rapid sea-level changes:
Glacioeustasy during the greenhouse world. Geology. v. 31, no. 7 (July),
Sahagian, D., Pinous, O., Olferiev, A., and Zakharov, V. 1996. Eustatic
Curve for the Middle Jurassic-Cretaceous Based on Russian Platform and
Siberian Stratigraphy: Zonal Resolution. AAPG Bulletin. v. 80, no. 9. p.
Stoll, H.M., and Schrag, D.P. 1996. Evidence for glacial control of
rapid sea-level changes in the Early Cretaceous. Science. v. 272, p.