hayes and eckel.] IRON ORES OF CARTERSVILLE DISTRICT, GA. 237 
between the formations on opposite sides has been observed at many 
points. The older rocks above always have a well-developed slaty or 
schistose structure, and are but little more altered immediately at the 
fault than elsewhere. The underlying rocks, on the other hand,, are 
much more intensely folded and brecciated immediately at the fault 
than a few feet distant. The fault plane itself is usually marked 
by a bed of breccia, a few inches or feet in thickness, and made 
up of the comminuted fragments of the formations on either side. 
This fault inane dips to the east, usually at angles varying between 
5° and 20°, and is parallel, in a general way, with the cleavage and 
bedding of the rocks on either side. 
The Weisner quartzite varies greatly in thickness within a short 
distance. It has the appearance of a delta formation rather than an 
evenly distributed littoral or marine deposit. North and south of its 
present outcrops in this region it probably becomes very much thin- 
ner, and its local thickening has doubtless influenced the structure in 
this region. Another factor which has been important in producing 
this peculiar structure is the presence of the great mass of granite to 
the east of the fault. This is the only point at which massive rocks 
of this character approach so near the fault line. They are usually 
separated from the western margin of the metamorphic rocks by a 
belt, several miles in width, of readily yielding slates and schists. It 
is evident that the conditions for the formation of a thrust fault of 
great lateral extent are much more favorable in bedded sedimentary 
rocks than in the massive igneous rocks, such as the Corbin granite 
The latter appears to have acted like an immovable buttress against 
which the rocks from the west were thrust. It will readily be under- 
stood that, on account of these massive quartzites on the west and the 
still more massive igneous rocks on the east, this portion of the Car- 
tersville fault differs materially from that to the north and south; and 
further, the reasons will be seen for the very considerable alteration, 
both physical and chemical, in the valley rocks adjacent to the fault. 
IRON ORES. 
The iron ores of the southern Appalachian region fall naturally into 
five distinct groups, as follows: (1) Magnetite, (2) specular hematite, 
(3) red hematite or fossil ore, (4) carbonate or black-band ore, and 
(5) brown hematite or limonite. Only two of these groups occur in 
the Cartersville district, namely, the specular nematite and the brown 
hematite or limonite, and of these, the latter is much the more 
important. 
Specular hematite. — This variety of ore occurs at two points in the 
district in sufficient abundance to be mined with profit. One is 
about 2 miles southeast of Warford and the other between Emerson 
and the Etowah River. The ore occurs at both localities as a band 
in the quartzite, and both the ore and the inclosing qua tzite have a 
