The Salt Lake herald-Republican. [volume] (Salt Lake City, Utah) 1909-1918, 1910-12-15

FORMATION OF
SAN JUAN FIELD
Eight Distinct 0il-Bearing
Sands Found in Canyon
Sections.

lleld nave not been determined. The
scene or the present development is
along Limestone creek. twenty-five
miles west OF Bluff. San Juan county.
Dtah, and the claims that have been.
staked are included IN an oval area
which has "A northeast southwest axis
OF about thirty miles. and northwest
syutncast axis OF twenty miles. aud is
~. ,, .oeu lnt9 nearly equal parts By the
canon Of san Juan river. SAYS IL H.
graphical survey.
The prices Of groceries. hardware
and other supplies at Bluff are in gen
1lal ln0sc az the railroad plus freight
ne freight from Dolores 10 Blur Is
800 and from Bluff to Goodridge 81
Fuel FOR boilers and for domestic
use consists at present OF driftwood
oto gsht down by san Juan river when
Labor for the most part will have
20 De brought in, although under skill
tul leadership the Indians could be re-
led upon 20 supply the demand FOR
labor In part. The Navaios parttcu-
workers
The san Juan oil field is part OF
province with altitudes rangi1E rom
1.VVO 90 1000 feet. composed largely Of
llat-lNing scdimentary rocks ranging
IN age from carboniferOus 20 cretace-
ous.' The river valleys are canyons cut
In solid rock. The elevations are either
messs and buttes remaining after the
erosion OF the surrounding areas or
are volcanic mcCks and lava-capped
Inesas. Much bare rock is exposed al
the surface. The area included in tine
on ueld mas an altitude of 1000 TO
5.VUO rect and differs in topography
from the typical Colorado plateau only
in that the rocks are folded into WELL
marked slnClnes aud auticlines.
The region is drained by san Juan
river, "a tributary To the Colorado. and
through this part Of its course IS "a
~ lnahehl stream. Ihe northern Jrlb-
utarlcs are Comb wash. Limestone
creek. Johns canyon and Grand gulch.
none or which lIOW permanently The
sands or Comb wash are. however. sat
uratcd with water. and springs issue
from the rock floor at several places
along the other tributaries. Limestone
valley carries the run-off from the re-
gtOu between the east auucnne ann
Cedar ridge. It's upper part is "a wide
VALLEY cut I'm sandstone. the lower
part is a box canyon.
The most prominent topographic
features in that part of the oil field
which lies north of San Juar, river
arc East auticliue and Cedar ridge.
East auticliue is fold six To- eight
miles wide. ON the west FLANK 81 which
are upturncd tue red rocks or Lime
stone valley on the west. and the ser
rate hoghaCk fthc COMB on the
east. Uncrodcd remnants of everything
rocks stand here ard there above the
exposed TOP OF the fold. but the gcner-
stone cap. Cedar ridge is broad mesa
terminating on the south and cu-f DID
PERCEPTIONS cliffs 900 20 600 tect IN
height This ridge is the uncr0dcd por-
tiOu or West antiClinc and stands
fourteen miles northwest OF East an
tiClinc. At the base OF Cedar ridge and
iu the syncliuc drained by Limestone
creek are many buttes aud pinnacles
OF grOtcsguc shape. 100 TO goo feet in
height. cut from the red sandstone and
shaic everything the limestone OF East
nN
cline flattcus and disappears and the
continuation Of cedar ride is repre-
scented 10y pinnaclcs. mon uucnts. and
flutcd huttcs. constituting one of the
most remarkable groups OF erosion
forms 20 De found iu the United states.
The smaller huttes. both north and
south % the river. are made Of strata
represented in Cedar ridge. the partic-
ular strata involved depending upon
the height and the position Of the
butte.
Geology.
In the OH field fat-Iyiug sediment
AIRY rocks fOuuu east. north. west and
south, are folded 20 form two anti
cliucs with broad Intervening SYM
companicd by faulting. Tho rock sys-
TENS that took part In the disturb
aucc and are now exposed by erosion
are The Carboniferous. Triassic and
Jurassic. Approximately 1000 feet Of
scdtmentary rocks above the fossil
bearing carbonifcrous arc i'm sight
east bank or Comb wash and continues
south and west along Gypsum valley
Co the vicinity OF ha-czkla rock an
pears Co represent the steep dowufoldcd
eastern side Of dome or monocline
which formerly extended westward to-
ward Colorado. This giant dome was
INCURRED hy SINAI Yer tclds. two OF winch.
with axis trcuding north twenty de-
grcs east and thus approx matcly par
aIicI Co the bordering nOgndCE. con-
stitutc the fundamental structural feat
a.fN HHHN AEHrH 81 u
an the wells so tar drilled are located
along the synclinc.
Tile rock wall bordering san Juan
river az Bluff are assumed to be Ju-
rassic age. the cliffs near The Twins"
being OF Ia Plata sandstone and the
McElmo formation appearing farther up
the river. IL d. probable that the Do
lorcs formation tTriassicl forms tho
base OF the cliffs and is rcsrcscntcd by
The well section at Bluff. In the sec
ton az tire Goodridgc bridge md az
Honakcr trail The upper Carbon srous
OPcnnsylvanianD is well exhibited.
Eight district oii-bearinE sands are
represented in tuc canyon section. These
sands are locally called the Baby. Good
rich. No. g. Mcndenhafl. Amber. Goose
Neck. Blue Shale and tionaker.
40 1ii places examine the rock con-
tanning the oil a. practically identical
IN character &C each horizon. it is =
white sandstone. probably blcachcd.
fiuc-grIincd. friahlc. generally porous.
ftN calcarcnus cement ana We1tnofs
With cnnCrrfiOuarN structure. MI the
beds are more or less fosSiliforuus. and
iu places consist 81 solid mass 81 shells
+ TIE porosifv OF tie oil sands is appar-
entity due 20 Che removal Of calcareous
fossils. Tic rock everything the Baby
-nn nd is a. dark blue. exec ntiousl1v dur
apie limestone. nat oNerlving the Good
l rich sand Is fossiliferous. firm lime
stone three feet thick. one of the
striking features Of the region is the
relative indestructibilitv OF these thin
/ beds OF limestone. So that the most
widespread surface rock. the one which
I Or large part controls the surface form,
I b. n tain cap rock of limestone. This
| limestone cap has prevented the escape
l OF the OIL upward and has thus allowed
| ~ TO accumulate in the porous sand.
KENO CHANGES.
The Koun 1Tfnfn~~ and arrffr-- com