JOURNAL 
OF THE 
WASHINGTON ACADEMY OF SCIENCES 
VoL. 13 DECEMBER 4, 1923 No. 20 
GEOLOGY.—The age of the supposed Lower Cretaceous of Alabama. 
Epwarp W. Brrry, The Johns Hopkins University.! 
A considerable area in eastern Alabama, extending from about the 
latitude of Montgomery eastward into’ Georgia was mapped in the 
80’s and 90’s of the last century by the Alabama and Georgia geologists 
as a part of the Tuscaloosa formation of western central Alabama.’ 
Stratigraphically the beds in question, which are predominately sands 
and clays, lie upon the crystallines, and are unconformably overlain 
by the sediments of the Eutaw formation. 
The physical evidence, admittedly inconclusive, led Clark, Stephen- 
son, and the writer, to tentatively regard them as the continuation 
of the ‘‘Hamburg beds” of South Carolina, the “Cape Fear” forma- 
tion of North Carolina, and the Patuxent formation of Maryland and 
Virginia. This opinion seemed to be partially confirmed by the 
discovery (in 1910 by L. W. Stephenson) of poorly preserved plant 
fossils in a bluff on the Tallapoosa River, near Old Fort Decatur in 
Macon County, Alabama. These fossils were submitted to the writer, 
who, although unable to conclusively determine any of the forms, 
was led by the presence of certain cycadophyte remains, to express 
the opinion that the deposit was of Lower Cretaceous age. The 
presence of numbers of dicotyledonous leaves led to the suggestion 
that these beds were younger than the Patuxent formation and could 
scarcely be older than the Patapsco formation of the Maryland- 
Virginia region. 
This opinion was quoted in whole or in part by Clark in 19113 
and by Stephenson in 1912 and 1914.4. The writer visited Old Fort 
1 Published by permission of the Director of the U. S. Geological Survey. 
2 Lanapon, D. W., Geol. Soc. Amer. Bull. 2: 587-606. 1890; Vearcu, Orro, Geol. 
Survey Georgia Bull., no. 18: 82-106. 1909. 
3 Cxiarx, W. B., Maryland Geol. Survey Lower Cretaceous pp. 96, 97. 1911. 
4 SrmpHENsoN, L. W., U. S. Geol. Survey prof. paper 71: 606. 1912; idem. 81: 11. 
1914. 
433 
