T4] 



GEOLOGICAL STRUCTURE. 



acquainted ; while the highest ridges in N. Mississippi of which 

 I have any knowledge exist in the waters of the Hatchie, in E. 

 Tippah, and in the hilly region dividing the waters of the Hatchie, 

 Tallahatchie and Tonibigbee. A table of such determinations of 

 elevation as I have been able to obtain, will be found in the 

 Appendix, at the end of the present volume. 



4. Geological Structure. — The general geological features of the 

 State are simple, and will be readily understood, in connection 

 with the foregoing remarks, by reference to the geological map ; 

 the subjoined table of the formations occurring in the State, their 

 several stages, principal materials, and character of fossils ; and 

 the general section, Fig. I, Table 1, in which, for the sake of a 

 fairer representation than could otherwise be given, a curved line 

 of projection (as indicated on the little map subjoined) has been 

 adopted. 



TABLE OF THE FORMATIONS OF MISSISSIPPI. 



NAME (IF GROUP. 



-5 

 £ L 



Alluvium 

 Second Bottom 

 Yellow Loam 

 Huff Formation 

 Orange Sand 

 Coast Pliocene? 

 Grand Gulf Group 

 Vicbbburq Group 



LlGNTflC 



Jackson Group 

 Lignitjc 



Claiborne Group j 



Northern Ijgnitic 



Ripley Group 

 Rotten Limestone 

 Tombigbee Sand 



ElTAW GlIOUP 



,£ ( Limestone 



z. -' -ANIiStoXK 

 £ ( BlACK SlATK 



PRINCIPAL MATERIAL* 



FOSSILS FOUND. 



Soils, sand-bars, etc., 

 "Hommooks," 



Brown and yellow brick-clays, 



Calcareous silt, 



Sands, pebbles, clays, 



Black fetid clsys, 



Light colored clays ; white sandstone: 



Marls and limestones, 



Black clays, 



Marls and soft limestones, 



Black clays, 



Marls and limestones, 



Siliceous sandstones, 



Black and grey clays ; yellow sands. 



Marls and limestones, sandy. 

 Oft chalky limestones, clayey, 

 Greenish micaceous sands, 

 Dark colored clays, sand. 



Fetid, crystalline limestone, 

 iliceous sandstone and chert, 

 Hydraulic limestone, 



, vis plants and animals. 



Terrestrial, part extinct. 



These of underlying formations. 



Living marine shells, living tree 3 



Plants partly extinct ? Lignite. 



Marine on;ia&&. 



Plants Lignite. 



Marine ani nials. 



Plants, Eig »ite. 



Marine animals. 



Marine animals. 



Plants partly extinct; Lignite, 



Marine animals. 

 Marine animals. 

 Marine animals. 

 Plants, extinct ; Lignite. 



Marine animals. 

 Marine animals. 



It will be perceived that four only of the principal geological 

 periods are represented, viz : the Carboniferous, Cretaceous, Tertiary 

 and Quaternary. In each of these, several stages, or minor sub- 

 divisions require to be distinguished. But before entering upon 

 a special discription of these, it is necessary to premise, that with 



