36 E. W. Hilgard on the Tertiary formations 
Report, that on the line between the Cretaceous and Tertiary in 
Barbour county, Ala., no similar strata occur. 
Stratigraphical conformation of the Tertiary.—I now turn to 
the consideration of some of the general stratigraphical phenom- 
ena of the Mississippi and Alabama Tertiary, which have given 
rise to misapprehensions regarding its dip and general arrange- 
ent 
I have stated (Miss. Rept., p. 107) that the general dip of the 
Tertiary strata of Mississippi seems to conform to that of the Cre- 
taceous strata—westward in the northern part of the state, and 
southward, or nearly so, in the southern. The westward dip of 
the old Lignitic does not appear to be much greater than the fall 
of the rivers, from the fact that on the waters of the Tallahatechie 
and Yallabusha, the same strata appear in the beds of streams 
for miles, before giving place to higher ones. Ido not think the 
dip can exceed four or five feet per mile; but the variability of 
materials and small extent of outcrops (which often exbibit local 
dislocations) render direct observations extremely difficult. 
we approach the region of southward dip, however, the inclina- 
tion becomes more decided and can be observed even in limited 
outcrops, on streams or railroad cuts trending southward. On 
Pearl river below Jackson, and on the Chickasawhay, there is 
no difficulty in recognizing the fact; but yet it is by no means 
ep., p. 145) and of the Jackson strata near Trotter’s plantation 
(ibid., p. 185) amounts to from 10 to 12 feet per mile, S. by W. 
But this is by no means the maximum or minimum observed, 
but refers to points where the great regularity of succession for a 
considerable distance seemed to indicate a normal configuration. 
If this estimate be correct (and I do not believe it will here- 
after be found to differ materially from the truth), it would go 
to prove that the upheaval which caused this dip as well as that 
of the Cretaceous system in Mississippi and Alabama, was a slow 
one. For the artesian borings on the territory of the former 
formation, have shown the dip to be about double the above, or 
25 feet per mile, in Monroe and Lowndes counties, Miss., and 
the adjoining portions of Alabama. On the other hand, the 
strata of the formation overlying the marine Tertiary in sout 
Mississippi possess so slight a dip as, at first, to render its very 
exisience doubtful, 
n the general (north and south) section accompanying Tuo- 
mey’s geological maps of Alabama, the Tertiary strata are rep- 
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