The Washington times., 1918-01-03
The Mystery of the Salt Dome
No One Has Solved 1t, but the Domes Are Almost
! . Certain Indications of Great Stores of Oil
By Garrett P. Serviss.

deed they are one OF the mysteries
2 Q; geology. yet they are Of immense
practical importance, and a method
Of quickly and surely locating hid
den domes might 90 far toward
saving the world from a dearth Of
EGturai oil and gas.
Mr.. Eugene W. Shaw OF the U. s.
Geological Survey suggests the pos
sibIlity OF using the varying In
teEs.ty OF gravity for detecting the
a1istence Of the precious domes
when their presence is not evident
o. the surface. This method de-
pends upon the fact that deposit
Of relatively heavy material at no
great depth under the surface
causes q local increase In the IN
tsnsity Of the force Of gravity,
which can be measured by the
swing OF a pendulum.
The process is a delicate one. but
n Mr.. shaw says: The time will
ne doubt soon come when 1T will be
profitable to spend a great deal OF
money searching for salt .domes. for
they seem 10 be much more likely
TO eoatsin oil than the surrounding
aOHHtry."
A salt dome, such as those found
Ga tas fiat regions Of Louisiana and
TeEss. is usually Of nearly equal
length and breadth, rarely exceed
ing two or three miles in its lateral
Dimensions, or falling below a half
nile. Some domes, Mr.. Shaw says,
ere marked by knobs from two or
three TO thirty feet IN height, while
Others that are very high struc-
turslIy have little or no effect on
tbe surface"
Again, he says that some make
a conspicuous hill. some, through
recent solution OF the salt. make a
depression. or basin, and some make
little appearance on the surface
The salt core sometimes lies at
slight depth and sometimes at a
great depth. e..
Tia substance Of q salt dome
comprises, IN additioR TO salt, dol.
oni;s, gypsum. sulphur, compressed
clay, and possibly igneoHs rO,k."
Usually, II not Invariably, the dome
sansAins valuable poole Of oil and
saS. Some doRes appear 10 lack
lhess pools. but coatiRReS inEesti-
nation generally results IN their die
eeTeCS,
FFca wtAE has bees said, it Is
RI.dsat that b. faE tie grsstNr part
~ the body of g dome lies beneath
tks surfacs, dSsoAadiae often TO
Gys<. depth. while the projecting
Port:oa is relatively snail.
iS<tIs Is known concerning the
lover parts Of deep dones, aGd coR-
SAq4entiy their. mode Of origin is
undetermined. One suggestion is
shak they are Fhe result OF volcanic
action, which sometimes thFusts up
pkxEs Of igneovs rock, but this
aAeIps inconsistent with the fact
kAs< deep borinss Do not reveal the
existence OF igneous rock in or
tsadeF the dores. where they exist
theTs Is practically no hard rock
WITHIN thousands OF feet OF the
sEzfaoe.
Another suggestion - that the
Zones are due TO forces o. erys-
iEl3izstion. the salt being derived
from saturated solutions and col
'ected around q nucleus By molecular
,t.rac:ion. Bat tbR absence o: salt
corrections III the domes. and the
apparent lacl. OF concentr!c struc-
turS are opposed 10 this view.
other suggested methods o. o.
Ic.G relate TO the possibility OF the
dsr-es having been formed b.
5s:csliaE and howage o. beds O.
SCca salt lying at a great depth. or
~ the results Of 'iEostatic adjust
Y:ent," which means An adjustment
q! equilibrium among the sub
ksnoes and strata Of varying density
n the crust OF the earth.
This does not AFFORD any clear
-4ea o. the actual method OF forma-
..oa Of the domes, or why they
should be 90 largely composed OF
Eait, and should contain oil pools
aad gas. The dome form. in itself,
Of course. helps 10 acooun; for ulr
presence Of oil and gas, since they
tend TO rise toward the summit o.
1Sch q formation. provided that
a;ley exist il it TO begin with.
The opinion is very strongly held
~ many that the chief origin o.
.,ztrolsum is from the deeomposi-
Ion OF marine organisms. both an
usal and vegetable. II the salt ~
nc domss was originally accuInu-
lated IN an ancient sea. filled with
organisms, then We have q conceiv-
Pble explanation Of the co-eXistence
% oil and gas IN the domeE.
81 whatevs- their origin may be.
.yhese strsnse formations IN the
Garth's crust are OF great practical
interest. and but for their existence
she worlds supply OF oil and gas
s-ould have been considerably less.
aey show how very slight Is our
l-too-iedze OF the treasures OF
.Dxtr stored up in the globe, aid
-ss,xgest that. as they were unknown
IL rs q generation ago, so some
LING yet more valuable may be dis
oveTsd during The generation 10