COOKE : JACKSON AND VICKSBURG DEPOSITS 



187 



made in 1913 and 1914 for the U. S. Geological Survey. It 

 contains also a synopsis of a manuscript report on the Jackson 

 formation and the Vicksburg group in Mississippi prepared in 

 partial fulfilment of an agreement between the U. S, Geological 

 Survey and the Mississippi Geological Survey for a co6perati\'e 

 investigation of the physiography, stratigraphy, and ground 

 waters of Mississippi. The correlations and names adopted are 

 shown in Table 1. 



TABLE 1 



Correlation of the Jackson and Vicksburg deposits in Mississippi 



and Alabama 



Age 



a 



o 



a 



o 

 o 



a 



O 



u 

 bC 



b£ 



M 



Mississippi 



Alabama 



BYRAM CALCAREOUS MARL 



Glendon limestone member 



Mint Spring ' .. "Chimney Rock" 

 calcareous marl . facie,* 



member 



FOREST HILL 

 SAND 



RED BLUFF 

 CLAY 



Yazoo clay member 



Moodys calcareous marl member 



OCALA LIMESTONE 



JACKSON FORMATION 



In Mississippi, Lowe" has divided the Jackson deposits into 

 formations described by him as Yazoo clay marl, Moodys Branch 

 green marl, and Madison sands. The last of these, which was 

 doubtfully placed in the Jackson by Lowe, is here referred to the 

 Vicksburg group and will be discussed later. The other two 

 intergrade so much that it seems advisable to consider them 

 members of a single formation rather than as constituting inde- 

 pendent formations. In the succeeding discussion they are 



* Lowe, E. N., Mississippi, its Geology, Geography, Soils, and Mineral Re- 

 sources. Mississippi Geol. Survey Bull. 12: 78-84. 1915. 



