The Crittenden record. [volume] (Marion, Ky.) 1904-1907, 1906-03-30
In The Engineering and
Mining Journal.
SETTING FORTH new idea
On classification .Oi Faults and Frac-
& lures Into Series and Sets and
It's Practical Application.
MAY PROVE OF GREAT LOCAL VALUE.

The diiieulty OF classifying the faults
and fractures Of section so that such
classification shall be- practical value,
has long been felt.in every mining field
where complex faulting has entered
into the question Of the location Of ore
deposits: and, as such regions are the
most common loci for ore and mineral
deposits, the question is Of prime i'm
portance Usually the best that can
be done is 10 classify the faults and
fractures. as having a northeast or
northwest strike. Miners have locally
given arbitrary names 10 the more
usual strikes. such are used in the
Erzgcbiagc Of the Harz and other
German mining regions, bnt outside Of
implying the direction Of faults or
hssures already found. they serve no
practical purpose.
In the study Of the veins and faults
Of Western Kentucky. became con-
yinced as early as 1902, that rather
definite relationships exist between the
strikes Of faults or fractures. and their
crosses. For instance. u was noted In
widely separated sections Of the dis
trict tina, fractures bearing N. Is deg
TO 90 deg T. would have crosses bear
ing n. - d.g. 10 25 deg. W. Again.
those bearing n. D deg. to g dsg. =.
would have crosses Of n. 3S deg. 10 90
deg W. etc. still others were found
in such regions as variant angles 20
these formed by those given. a. for
example in the Columbia Mines section.
In Critlcndcn county. where the last
mentioned bearings obtain, fractures
bearing n. 10 deg. TO 70 deg +. were
noted Such being the case. use was
made Of the relationships noted by me
in various sections Of the field without
any attcmpi at their reduction 20 a
common relationship.
shortly aftcrwarl. ! saw Hobbs
work on the faults of the Pompcraug
Valley, Connecticut Hobbs had noted
somewhat similar relationship, Hc
attempted 20 explain the formation u
the courses II set. by constructing
parallclogpms having ljO and 9oO feet.
respectively. Tor sides. and hy using a
number of these In different comhina-
tions. to arrive at the different
courses.
It was not until very recently that
conceived the idea II common rcla.
tionship between members of a set II
fractures, having accidentally arrived
at Il in working up the data in hand
relative To the structure Of Western
Kentucky. for presentation In the r..
ports. II was noted In the field work.
that, almost constantly close approachc.
to w and 90 deg. Tor angles formed
between joints and their crosses. Oh.
tanned, both IN saudsioncs and lime,
stones. this gave the clue. Burk,
obtained the angles of ~ deg. and l2l
deg. for joints In great mary insisn.
ccs In the same field Upon ,abulaiiur
In three s,ts. the northwcsicrly course.
most usually found In the hcld. using Z
range ~ 20 irr, and adding respect
i,cly n nl and i2n deg. thc mcmbcy
grouped under the thrcc remaining
series. uorth.NIthcast cast-northCasU
and wcstporthWcst. were obtained fol
each set and these found to agree To-
markably with the strikes " crcssc
observed in the field
/ Upon measurement oi the anglcl
formed by the assures shown upon N,
map ot the frvihcrr district. similal
angles were closely approach,
great many instances. both Tor hssurc.
of the sam, type and for those to
other tvprs where they crossed cacl
other Angles closely approaching Il
deg. and ~ dcv. formed by three set
u fractures, were found In the plate o.
a specimen " jasper from Minnesota
shown by l.cith to exhibit fractur'
cleavage. The latter is typihcd hi
regions when normal faulting has pm
duccd faul, block structures.
With these data az hand. the follow
iw rule was de,luccd. tbs 30 b. appli