1911 Encyclopædia Britannica/Albian
|←Albi|| 1911 Encyclopædia Britannica, Volume 1
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ALBIAN (Fr. Albion, from Alba = Aube in France), in geology the term proposed in 1842 by A. d'Orbigny for that stage of the Cretaceous System which comes above the Aptian and below the Cenomanian (Pal. France. Cret. ii.). The precise limits of this stage are placed somewhat differently by English and continental geologists. In England it is usual to regard the Albian stage as equivalent to the Upper Greensand plus Gault, that is, to the "Selbornian" of Jukes-Browne. But A. de Lapparent would place most of the UPper Greensand in the Cenomanian. The English practice is to commence the upper Cretaceous with the Albian; on the other hand, this stage closes the lower Cretaceous according to continental usage. It is necessary therefore, when using the term Albian, to bear these differences in mind, and to ascertain the exact position of the strata by reference to the zonal fossils. These are, in descending order, Pecten asper and Cardiaster fossarius, Schloen bachia rostrata, Hoplites lautus and H. interruptus, Douvilleiceras mammillalum. In addition to the formations mentioned above, the following representatives of the Albian stage are worthy of notice: the gaize and phosphatic beds of Argonne and Bray in France; the Flammenmergel of North Germany; the lignites of Iltrillas in Spain; the Upper Sandstones of Nubia, and the Fredericksburg beds of North America.
See GAULT, GREENSAND, and CRETACEOUS. (J. A. H.)