GEOLOGY AND COAL RESOURCES OF
MESITA DE YES0 QUADRANGLE, CIBOLA COUNTY, NEW MEXICO
NEW MEXICO BUREAU OF MINES AND MINERAL RESOURCES
OPEN-FILE REPORT 171
by
ORIN J. ANDERSON
August 1982
Contents:
(1) Discussion of Geology and Coal Resources
(2)
Geologic Map with cross sections (accompanying)
Contents
GEOLOGY
General
P.
1
Study Area
P.
7
Structure
P.
7
Stratigraphy
P.
9
Tertiary
p. 25
.
Rocks
COAL RESOURCES
p. 27
REFERENCES
p. 29
Figures
Fig. 1.
Fig. 2.
Fig. 3 .
Index map of study area showing
monoclines and modern erosional
truncation of TresHermanos Formation.
P-,
Composite stratigraphic column for
Mesita de
Yeso-Los
Pilares area.
p. 14
Composite stratigraphic column for
Mesita de Yeso-Shoemkaer Canyon SE
quadrangle
boundary
area.
p. 22
2
GEOLOGY
General
l i e s i nt h es o u t h w e s tp a r to f
T h e Mesita d eY e s oq u a d r a n g l e
t h e Z u n i B a s i n , a b r o a d ,s h a l l o ws t r u c t u r et h a te x t e n d s
s o u t h w e s t w a r df r o mt h eZ u n iM o u n t a i n so f
c e n t r a lA r i z o n a .
A s such,
N e w M e x i c oi n t oe a s t -
t h e quadrangle l i e s near t h e southeast
m a r g i no ft h eC o l o r a d oP l a t e a u .T h er e g i o n a ld i pi nt h es t u d y
a r e a i s v e r yg e n t l y ,b u tp e r c e p t i b l y ,n o r t h e a s t w a r dt o w a r dt h e
G a l l u ps a gw h i c hc o m p r i s e s
t h e n o r t h e a s ta n dd e e p e s tp a r to ft h e
Zuni B a s i n .T h en o r t h e a s t w a r dd i p s
a r e i n t e r r u p t e dl o c a l l yb y
b r o a d ,l o wa m p l i t u d e ,N W - S E - t r e n d i n gf o l d s ,b yN W - S E - t r e n d i n g
m o n o c l i n a lf l e x u r e su po nt h en o r t h e a s ts i d e ,a n da l s o
faulting.
area.
by m i n o r
A t l e a s t two m o n o c l i n e sh a v eb e e ni d e n t i f i e di nt h e
t h e t w o i s t h eA t a r q u e
T h e l o n g e s ta n dm o s tp r o n o u n c e do f
m o n o c l i n e( A n d e r s o n ,
198213) w h i c he x t e n d s
15 m i n o r t h w e s t w a r d
from t h e A t a r q u e L a k e q u a d r a n g l e a c r o s s t h e n o r t h e r n p a r t
V e n a d i t o Camp q u a d r a n g l e .
n o r t h w e s t w a r df r o mt h e
of t h e
T h e o t h e rm o n o c l i n ee x t e n d s
Mesita d e Y e s o q u a d r a n g l e a c r o s s t h e
it
s o u t h w e s te d g eo ft h eU p p e rG a l l e s t i n aC a n y o nq u a d r a n g l ew h e r e
flattens outfor
2 1 / 2 m i a n d t h e n c o n t i n u e sn o r t h w e s t w a r di nt h e
P l u m a s a n oB a s i n nq u a d r a n g l e( F i g .
1); t h i s l a t t e rm o n o c l i n ec a n
be t r a c e d f o r a p p r o x i m a t e l y 1 2 - 1 4 m i a n d i s r e f e r r e d t o a s t h e
G a l l e s t i n am o n o c l i n e ,a l s o
o nF i g .
1.
T h e s em a j o rs t r u c t u r a le l e m e n t sp a r a l l e lt h ea x i so f
Z u n iu p l i f t ,b u tp e r h a p sj u s t
a s s i g n i f i c a n t l y ,t h e ya p p e a r
the
to
r e p r e s e n tt h es o u t h e a s t w a r de x t e n s i o no ft h es t r u c t u r a la x e st h a t
wrap around t h e s o u t h e r n e n d o f t h e Defiance u p l i f t , a s s h o w n b y
1
2
350
Noith Plains
l a v a beds
TRUNCATION
XmP
OUTHWFSTERN
O F K l A fA N D
R l N C D N HONQO
uni- Bandera flows
:;".".","::,.","d":',.,
P e s c o d o Tongu.
a
-
0
2
4
6
Study ace0
8
Sprlngerville
Index
map
o f study
area
Tres
Hermanos
Formation.
showing
monoclines
and
truncation
Moncor Shale
F l t e Rmnch m * m b * i , T r e s
Miles
Fig. I
of
of
H.rmonor
Fm.
D a v i sa n dK i v e n( 1 9 7 5 ) .
T h e s e s t r u c t u r e sa l s oa l i g nv e r yc l o s e l y
w i t ht h en o r t h w e s t - t r e n d i n gd i k es y s t e mi n
t h e TheDyke,Techado,
P i e Town a r e a s .
Adams D i g g i n g s ,a n d
are t h e most s i g n i f i c a n t s t r u c t u r a l
T h em o n o c l i n a lf l e x u r e s
a much b r o a d e rc o n t e x t .
f e a t u r e sp r e s e n tn o to n l yl o c a l l yb u ti n
K e l l y (1955) s t a t e d t h a t" I n
many r e s p e c t st h em o n o c l i n e sa r et h e
Most o f
p r i n c i p a ls t r u c t u r a lf e a t u r e so ft h eC o l o r a d oP l a t e a u .
t h ed e f o r m a t i o nh a so c c u r r e da l o n g
r e l a t e d t ot h ec o n c e p t
them."
of n o r t h e a s t - s o u t h w e s t h o r i z o n t a l
area d u r i n g t h e L a r a m i d e
c o m p r e s s i o no ft h eC o l o r a d oP l a t e a u
orogeny.
As a r e s p o n s et ot h er e g i o n a lc o m p r e s s i o n ,
i n d i v i d u a lb a s e m e n tb l o c k s
1978).
--
G r o u p i n g so ft h e s em o n o c l i n e s
--
100 m i i n l e n g t h
t h e b a s i s o fs i m i l a r i t yo ft r e n d s ,w h i c h ,
d e e pf a u l t s ,s e r v et os u b d i v i d e
These
i n t h eo v e r l y i n g
r e v e r s ef a u l t sp r o d u c e dm o n o c l i n a lf o l d i n g
t r a c e df o rm o r et h a n
discrete,
were u p l i f t e d by r e v e r s e m o v e m e n n t s
a l o n gs e g m e n t so fh i g h - a n g l ef r a c t u r ez o n e s( D a v i s ,
strata.
is
T h e i rs i g n i f i c a n c e
someofwhich
may b e
h a v eb e e na t t e m p t e do n
when r e l a t e d t o t h e
t h e P r e c a m b r i a nb a s e m e n ti n t o
a
mosaic o f c r u s t a l b l o c k s .
The r o c k u n i t s t h a t c r o p o u t i n t h e a r e a u n d e r
c o n s i d e r a t i o na r e
1) Upper C r e t a c e o u s s a n d s t o n e s a n d s h a l e s t h a t
exceed 500 f t i n t h i c k n e s s w h e r e t h e
T r e s H e r m a n o sF o r m a t i o n
( H o o kM
, o l e n a a r a, n dC o b b a n[ 1 9 8 3 ]i np r e s s )
is present,
2)
h i g h l yc r o s s b e d d e de o l i a ns a n d s t o n e so fJ u r a s s i ca g et h a tr a n g e
u pt o1 0 0f ti nt h i c k n e s s ,a n d
s i l t s t o n e s ,a n ds a n d s t o n e st h a t
3 ) T r i a s s i c s h a l e s ,m u d s t o n e s ,
makeup
t h e C h i n l eF o r m a t i o n ,
w h i c h i s e s t i m a t e d t o be 800-1,000 f t t h i c k l o c a l l y
3
J
(see Anderson
1 9 8 2 bO
; ' S u l l i v a n1, 9 7 7 )A
. dditionally
a 3 2 - f t - t h i c ks e c t i o no f
f l a t - b e d d e d lr e d d i s h - b r o w ns i l t ys a n d s t o n ea n ds a n d ys i l t s t o n e
t h a t is w e l l e x p o s e di nt h e
q u a d r a n g l eb o u n d a r y
Los P i l a r e s a r e a l
500 f t s o u t h o f
i s sec. 14, may be t h e e q u i v a l e n to f
t h e Rock
P o i n t Member o f t h e W i n g a t eS a n d s t o n e( T r i a s s i c )d e s c r i b e d
H a r s h b a r g e rR
, e p e n n i n ga, n dI r w i n( 1 9 5 7 /
sandstone-siltstone
by
Howeverl
p. 8 ) .
the
this
i s n o t a m a p p a b l eu n i tt h r o u g h o u tm o s to ft h e
Mesita d eY e s oq u a d r a n g l e .
i n t h e s u b s u r f a c e may b ei n f e r r e d
The P a l e o z o i c s e c t i o n
f r o m a n o i l t e s t d r i l l e d 1 0 m i t o t h e n o r t h o f t h e Mesita d e
Yesoquadrangleinthe
N E 1 / 4 sec. 5 , T. 9 N.,
by C i t i e s S e r v i c e O i l Co.
c o m m u n i c a t i o n )T
. his
P a l e o z o i cr o c k sc a p p e d
R.
( M a x w e l la n dN o n i n i lo r a l
t e s t p e n e t r a t e d a 1,400 f t s e c t i o no f
by t h e S a nA n d r e sL i m e s t o n e .
p r e s u m p t i o nt h a tt h i c k n e s s e sl o c a l l ya r eu n i f o r m ,
s e c t i o no fa p p r o x i m a t e l y2 , 9 0 0
b a s e m e n t may b ep r e s e n t
Upon t h e
a sedimentary
f t o v e r l y i n gt h eP r e c a m b r i a n
i n t h e s t u d ya r e a .
S c a t t e r e dr e m n a n t so f
F o r m a t i o na r ep r e s e n t
t h e U p p e rT e r t i a r yB i d a h o c h i
i n t h ea r e af r o mt h en o r t hs i d eo fC a r r i z o
C r e e ko nt h es o u t ht oP i n e h a v e no nt h en o r t h .
This unit
m a t e r i a l d e p o s i t e da l o n g
r e p r e s e n t sa na p r o no fa l l u v i a l
a n c e s t r a l L i t t l e C o l o r a d o R i v e r d r a i n a g eb a s i n .W i t h i n
M e s i t ad eY e s oq u a d r a n g l e ,t h ef o r m a t i o n
t o p o g r a p h i cf e a t u r ef r o mw h i c ht h eq u a d r a n g l et a k e s
Here t h e B i d a h o c h i c o n s i s t s o f
I
the
the
i t s name.
w h i t e o rp i n k i s hg r a ys a n d s t o n e
w i t h clastlithologiessuggesting
4
Ls
the
is r e s t r i c t e d t o
i t c a p s Mesita d eY e s o ,
s o u t h - c e n t r a lp o r t i o nw h e r e
a
i n t h e u p p e r reaches o f t h e
n o r t h w e s t - t r e n d i n gf l u v i a ls y s t e m
a n dc o n g l o m e r a t e
i n 1963
1 8 W.,
a s o u r c ea r e a
east of
i n t h e D a t i l , M a n g a s ,a n dG a l l oM o u n t a i n ss o u t ha n d
Quemado.
R e w o r k i n go ft h ec o a r s e - g r a i n e df l u v i a ld e p o s i t so nt h e
Z u n i P l a t e a u a n d S a n t a R i t a Mesa t o t h e s o u t h may h a v e p r o v i d e d
a d d i t i o n a ls o u r c e s .B a s a le l e v a t i o n so ft h i sd e p o s i to nS a n t a
R i t a Mesa r a n g eb e t w e e n
7 , 2 0 0 a n d 7,300 f t , w h e r e a st h e
Mesita de Yeso is b e t w e e n 7,000 a n d
t h eB i d a h o c h iF o r m a t i o no n
two may be e q u i v a l e n ta g e .N o r t h w a r d
7,100 f t :a l t e r n a t i v e l yt h e
inthevicinity
of P i n e h a v e nt h ep r e s e n c e
t h ef o r m a t i o ni n d i c a t e s
base of
of g r a n i t i c d e b r i s i n
a s o u r c e a r e a i nt h eg r a n i t e - c o r e dZ u n i
M o u n t a i n s( r e p e n n i n ga n do t h e r s ,
1958).
l o c a l s e c t i o n occur a t s y s t e m
M a j o ru n c o n f o r m i t i e si nt h e
b o u n d a r i e s - t h eJ u r a s s i c / T r i a s s i c ,
t h e C r e t a c e o u s / J u r a s s i c ,a n d
is an
t h eT e r t i a r y / C r e t a c e o u s .T h eU p p e rJ u r a s s i cZ u n iS a n d s t o n e
e o l i a na n dp a r t l yf l u v i a lu n i td e p o s i t e du n c o n f o r m a b l y
Rock P o i n t Member o ft h eW i n g a t eS a n d s t o n e .
t h e Rock P o i n t s u r f a c e
on t h e
T h e l o c a l r e l i e f on
may a p p r o a c h 1 0 0 f t , a s i n
the southeast
c o r n e ro ft h eP l u m a s a n oB a s i nq u a d r a n g l e .I nt h eF e n c eL a k e
q u a d r a n g l ej u s t
e a s t o f t h e t o w n s i t e of A t a r q u e ,t h eZ u n it h i n s
c o n s i d e r a b l ya n dc o n t a i n ss o m ea t y p i c a l
f a c i e s , n a m e l yr e d d i s h -
b r o w n ,v e r yf i n eg r a i n e d ,s i l t ys a n d s t o n e s .S i x t e e n
miles t o
t h es o u t h ,a l o n gC a r r i z oC r e e k ,t h eJ u r a s s i ch a sd i s a p p e a r e d
c o m p l e t e l y .T h u s ,t h es o u t h w a r dp i n c h o u to fJ u r a s s i cr o c k so c c u r s
60 m i d u e w e s t o f t h e a r e a i n w h i c h S i l v e r ( 1 9 4 8 ) f i r s t n o n t e d
t h ep i n c h o u ti nh i sp a p e rd i s c u s s i n gJ u r a s s i co v e r l a p .T h i s
east-west c o n t r o l on
s o u t h w a r dp i n c h o u ti n d i c a t e ss t r o n g
J u r a s s i cs e d i m e n t a t i o n .
5
T h eD a k o t aS a n d s t o n ef o r m st h eb a s a lC r e t a c e o u sr o c k si n
100 f t o fn o n m a r i n e ,
t h i s area a n d c o n s i s t s o f a p p r o x i m a t e l y
were
m a r g i n a lm a r i n e ,a n dm a r i n es a n d s t o n e sa n ds h a l e st h a t
depositedinfront
of a n d i m m e d i a t e l y b e h i n d t h e s h o r e l i n e
time.
a d v a n c i n n gi n t e r i o rs e a w a yd u r i n gC e n o m a n i a n
two-thirds
t o t h r e e - f o u r t h s of t h e f o r m a t i o n
shales.
T h el o w e r
i s n o n m a r i n e ,w i t h
a t t h eb a s eo v e r l a i n
f l u v i a l - c h a n n e ls a n d s t o n e s
of t h e
by p a l u d a l
The s h a l e s a r e l o c a l l yc a r b o n a c e o u sw i t hv e r ym i n o r
a r e o fp o o r
c o a l yb e d s .T h ev e r yt h i n ,l e n t i c u l a r rc o a l yb e d s
a t r a n s g r e s s i v es e q u e n c e .
q u a l i t ya n dr e p r e s e n ta c c u m u l a t i o ni n
F o l l o w i n gt h eD a k o t a - M a n c o st r a n s g r e s s i o n rt h er e g r e s s i v eM o r e n o
H i l l Formationandthepartlyequivalent
T r e s H e r m a n o sF o r m a t i o n
p r e s s ) were d e p o s i t e d
(HookM
, o l e n a a r a, n dC o b b a n1 9 8 3 /i n
t h r o u g h o u t much of w e s t - c e n t r a l N e w M e x i c o .T h e s ep a r t l y
e q u i v a l e n tu n i t sc o n t a i n
c o a l i nb e d su pt o
2 and 3 f t i n
t h i c k n e s s ,l o c a l l yt h i c k e r( C a m p b e l l ,1 9 8 1 )a n do fh i g h e rq u a l i t y
t h a nt h a tf o u n di nt h eD a k o t a .
The c o a lo c c u r r e n c e s
Mesita de Yeso q u a d r a n g l e a r e s o m e w h a t t h i n n e r t h a n
essentiallyrestrictedtothe
C o a lr e s o u r c e s
t h i s and are
T r e s H e r m a n o sF o r m a t i o no u t c r o p s
t h e G a l l u p - Z u n ic o a l
w h i c hh e r ed e f i n et h es o u t h w e s te d g eo f
field.
on t h e
a r e d i s c u s s e di n
g r e a t e r d e t a i li nt h e
l a s t s e c t i o n of t h i s r e p o r t .
S t u d y Area
Structure
The g e n t l e n o r t h e a s t e r l y d i p s p r e v a l e n t i n t h e M e s i t a
Y e s oq u a d r a n g l ea r e ah a v ep r o d u c e d
a t o p o g r a p h yc o n s i s t i n go f
6
de
s a n d s t o n e - c a p p e d low mesas a n d n o r t h w e s t - s o u t h e a s t - t r e n d i n g
c u e s t a sS
. u p e r i m p o s e do nt h i s t r u c t u r a fl r a m e w o r k
are
1) a
m i n o r s t r u c t u r a l h i g h i n t h e f o r m o f a d o m e c a l l e d Mesita d e Y e s o
i n t h es o u t h - c e n t r a lp o r t i o no ft h eq u a d r a n g l ea n d2 )
m o n o c l i n a lf l e x ,
a
o r a s s y m m e t r i ca n t i c l i n e ,c o n s i d e r e dt ob et h e
G a l l e s t i n a m o n o c l i n e ( s e e Fig.
s o u t h e a s te n do ft h e
part of t h e quadrangle.
e x t e n d si n t ot h en o r t h - c e n t r a l
T h e Mesita d e Y e s o h i g h
l), w h i c h
i s more a c c u r a t e l y a n o r t h e a s t by a
t r e n d i n ga n t i c l i n a lf o l dp l u n g i n gn o r t h e a s ta n dt r u n c a t e d
f a u l t ( s )a t
i t s s o u t h w e s te n d .
west e x t e n d s i n t o
f a u l t o nt h e
A northwest-trending
sec. 1 4 of t h eq u a d r a n g l ef r o m
t h e Los P i l a r e s
t h e s o u t h w e s t t e r m i n u s of
a r e ai m m e d i a t e l ys o u t ha n dp a r a l l e l s
Mesita d eY e s o ;h o w e v e r ,t h ef a u l tc a n n o tb et r a c e da c r o s st h e
d r a i n a g et o
a t Los P i l a r e s i s
t h e n o r t h .T h ed i s p l a c e m e n t
a p p r o x i m a t e l y2 5
ft.
A d d i t i o n a lf a u l t i n g
a n d 1 4 i m m e d i a t e l ys o u t h
i s shown i n secs. 13
of t h eq u a d r a n g l eb o u n d a r yo nt h eF e n c e
L a k eq u a d r a n g l eb yM c L e l l a na n do t h e r s( 1 9 8 1 ) ,b u t
these f a u l t s
a northwest-trending f a u l t
c a n n o tb et r a c e dn o r t h w a r d H
. owever,
s h o w n b y t h e s e a u t h o r s a s f o l l o w i n g C a n o n A n c h o i n s e c . 1 3 may
p o s s i b l ye x t e n dn o r t h w e s t w a r dt oi n t e r s e c t
i n t h e S E 1 / 4 s e c . 11, T. 6 N.,
R.
1 8 W.
a n o r t h - t r e n d i n gf a u l t
( s h o w no nt h e
accompanyingmap).
M e s i t a d e Y e s o i s a p p a r e n t l y a cross f o l d v e r y similar t o
t h o s ed e s c r i b e do nt h eV e n a d i t o
t ot h e
Camp a n d A t a r q u e L a k e q u a d r a n g l e s
west ( A n d e r s o n ,1 9 8 2 a ,b ) ,w h e r et h e y
a r e t h o u g h tt ob e
r e l a t e d t o t h e s i n u o s i t yo ft h en o r t h w e s t - t r e n d i n gA t a r q u e
monocline (see Fig.
1).
T h e M e s i t ad eY e s o
t o t h e structureformingthe
i s e s p e c i a l l y similar
s e c . 5 mesa (T. 6 N., R. 1 9 W.)
7
on
Mesa C o l o r a d o , a p r o m i n e n t l o c a l
t h eA t a r q u eL a k eq u a d r a n g l e .
f e a t u r ej u s to f ft h ew e s t e r ne d g eo ft h es t u d y
t o owe i t s p r o m i n e n c e t o
area, is thought
a t h i c k e n i n g of t h e J u r a s s i c s a n d s t o n e
s e c t i o nr a t h e rt h a nt oa n ys i g n i f i c a n t
cross f o l d i n g( A n d e r s o n ,
1982b).
a t the
T h em o n o c l i n a lf l e x u r et h a te n t e r st h eq u a d r a n g l e
northwestcornerandterminatesjustshortof
s t r u c t u r es e c t i o n
A-A'
o n t h e a c c o m p a n y i n g map.
r e c o r d e do nt h em o n o c l i n a lf a c e
3 4 of T. 8 N.,
NM-32
R. 1 8 W.);
i s shown i n
Maximum d i p s
were o n l y 110 s o u t h w e s t ( i n
sec.
n e v e r t h e l e s s , t h e f l e x u r e is a
d i s t i n c t ,a b r u p t ,l i n e a rf e a t u r e ,h e r ec o n s i d e r e d
t o be t h e
of S t r i c k e r
s o u t h e a s t w a r de x t e n s i o no ft h eG a l l e s t i n am o n o c l i n e
a n dA n d e r s o n( 1 9 8 3 i, np r e p a r a t i o n ) L
. i k et h eA t a r q u em o n o c l i n e
1 0 m i t o t h e s o u t h w e s t ,t h i sm o n o c l i n eh a s
a ne s p e c i a l l y
a s i n u o u st r a c ew i t h
s h a r p bend a t t h eq u a d r a n g l eb o u n d a r yi n
sec.
34.
B o t h these m o n o c l i n e sa r el i k e l yt ob ea s s o c i a t e dw i t hh i g h - a n g l e
o rh i g h - a n g l e - r e v e r s ef a u l t si nt h eP r e c a m b r i a nb a s e m e n t
a s shown
on t h e map cross s e c t i o n .T h eo r i g i no fh i g h - a n g l eb a s e m e n t
f a u l t sh a sb e e nd i s c u s s e db yD a v i s( 1 9 7 8 ) ,
who c o n s i d e r e dt h e mt o
be a r e s p o n s e t o n o r t h e a s t - s o u t h w e s t - d i r e c t e d h o r i z o n t a l
c o m p r e s s i o n a t t h eC o l o r a d oP l a t e a ud u r i n g
t h e L a r a m i d eo r o g e n y .
The f a u l t sp r o d u c e dt h em o n o c l i n a lf o l d i n gt y p i c a lo ft h e
Colorado P l a t e a u .
O t h e rs t r u c t u r e so nt h eq u a d r a n g l ec o n s i s t so f
a curved,
n o r t h w e s t - t r e n d i n g ,a s y m m e t r i ca n t i c l i n a lf o l di nt h e
36, T. 8 N.,
S
R. 1 8 W. a n d a n e a s t - w e s t - t r e n d i n g f a u l t i n
extreme s o u t h e a s tc o r n e ro ft h eq u a d r a n g l ei n
8
1 / 2 sec.
the
secs. 1 6 a n d1 7 ;
t h e t r a c e o ft h i sf a u l tf o l l o w sT e r r e r o
Draw.
T h eu p t h r o w nb l o c k
i s on t h e n o r t h , b u t a p p a r e n t l y e a s t w a r d t i l t i n g o f t h e u p t h r o w n
b l o c ko c c u r r e d
a s g r e a t e rd i s p l a c e m e n te x i s t so nt h e
west end.
T h i st i l t i n g" a g a i n s td r a i n a g e "h a sr e s u l t e di nt h ef o r m a t i o no f
swamp c o n d i t i o n s f r o m
time t o time i n T e r r e r o Draw a s i s
i n s c a t t e r e dp a t c h e s .
e v i d e n c e db yt h eb l a c k ,p e a t ys o i l sf o u n d
Stratigraphy
The o l d e s tr o c k se x p o s e d
on t h eq u a d r a n g l ea r et h o s eo ft h e
was mapped, i t was n o t
C h i n l eF o r m a t i o n .A l t h o u g ht h ef o r m a t i o n
s t u d i e d i n d e t a i l b e c a u s e o u t c r o p sa r e p o o r a n d m o s t o f t h e a r e a
u n d e r l a i n by t h eC h i n l e( t h es o u t h w e s tc o r n e ro f
a l l u v i a lc o v e r .C o n s i d e r a b l e
b e c a u s eo f
a r e a s o fa l l u v i u m
t h e map) h a s a n
were mapped h e r e
of t h e Rock
t h e u n c e r t a i n t ys u r r o u n d i n gt h ee x t e n t
P o i n t Member o ft h eW i n g a t ea n d
d i s a p p e a r a n c eo ft h e
t h e s u d d e na p p e a r a n c ea n d
J u r a s s i c s a n d s t o n e sl o c a l l y .
T h e u p p e rp a r to ft h eC h i n l el o c a l l yc o n s i s t so fr e d ,
m a r o o n ,a n dg r a ym u d s t o n e ,s i l t s t o n e s ,s h a l ea n dt h i ns a n d s t o n e s
t h a t a r e a s s i g n e dt ot h eP e t r i f i e dF o r e s t
Member.
Stewart,
P o o l e ,a n dW i l s o n( 1 9 7 2 )d e s c r i b e da n dm e a s u r e ds e c t i o n so ft h e
C h i n l e a t t w on e a r b yl o c a l i t i e s .
J o h n s ,A r i z o n a ,b e t w e e n
thePetrifiedForest
s e q u e n c et h a t
N e w M e x i c o ,1 7 8
A t o n el o c a l i t yn o r t h
34O42'N a n d3 4 0 4 6 ' N It h e
upper p a r to f
Member is 5 9 1 f t t h i c k w i t h i n
i s 827 f t t h i c k .
A t t h eo t h e rl o c a l i t y
f t o fP e t r i f i e dF o r e s t
of S t .
a totalChinle
near Zuni,
Member was measured.The
t h i c k n e s s o f t h e C h i n l ewas n o t d e t e r m i n e d i n t h e s t u d y a r e a a s
t h eb a s e
i s n o te x p o s e d .T h eC h i n l ew a se s t i m a t e dt ob e
1,000 f t t h i c k on t h ea d j a c e n tA t a r q u eL a k eq u a d r a n g l e
9
800 t o
by
Anderson (198233).
isopach a few
O'Sullivan (1977) placed his 400-m
miles the
to
north
of
the
Mesita
(1,320-ft)
de
Yeso
quadrangle
area, with the Chinle Formation thinning to the south.
A 32-ft-thick section of reddish-brown, flat-bedded silty
sandstone is exposedat Los Pilaresjust 500 ft south of the
quadrangle in sec. 14 (T. 6 N.,
Formation mudstones and shales.
considered
to
be
the
R. 18 W.) where
it
rests
on
Chinle
This uniform sequence ishere
equivalent
ofthe
RockPoint
Member
ofthe
Wingate described by Harshbarger, Repenning, and Irwin (1957, p.
8 ) as a pale-reddish-brown silty sandstoneat the type locality
near Rock Point,' Arizona.
They further interpreted it as a quiet
water deposit that accumulatedin a southward-plunging basin
(Rock Point Lagoon) fed by streams entering from the northeast,
east, and southeast.
lagoon was
An embayment at the eastern margin of the
shown extending across the New Mexico State line in
the Zuni-Atarque area.
The Rock Point Member, however, becomes
unmappable a very short distance north of Los Pilares inside sec.
11, T. 6 N., R.
18 W. (see
accompanyingmap).
Its
presence
e
northward from this point onthe quadrangle is uncertain: it
appears as a 6-ft-thick unit at the base of Mesa Colorado, just
off the west boundary of the quadrangle (Anderson, 1982b).
The white, fine-grained, crossbedded sandstone comprising
the uppermost Jurassic rocksand capped by the Dakota Sandstone
is the Zuni Sandstone.
Anderson (1983, in preparation) defines
the Zuni as consisting of the undivided equivalents of the Cow
Springs and EntradaSandstones.
The name Cow Springswas
proposed by Harshbarger, Repenning, and Jackson (1951) for the
greenish-gray to light-yellowish-gray, fine-grained, crossbedded
10
I
s a n d s t o n et h a tw e a t h e r st og r a y i s h - w h i t er o u n d e d
A t the
cliffs.
t y p e s e c t i o n 4 m i e a s t o f Cow S p r i n g s , A r i z o n a , t h e C o w S p r i n g s
S a n d s t o n e i s 3 4 2 - f t - t h i c ka n d
i s u n c o n f o r m a b l yo v e r l a i n
by t h e
D a k o t aS a n d s t o n e A
. d d i t i o n aw
l o r kb yH a r s h b a r g e r R
, epenninng,
a n dI r w i n( 1 9 5 7 )e x t e n d e dt h e
N e w Mexicb, w h e r e t h e y s t a t e d
Z u n iR e s e r v a t i o no f
A 440-ft-thick
Rock was d e s i g n a t e d a s Cow S p r i n g s S a n d s t o n e
r e s t i n go nt h ef l a t - b e d d e d
Rock P o i n t Member o ft h eW i n g a t e
S a n d s t o n ea n du n c o n f o r m a b l yo v e r l a i n
From t h e r e t h e u n i t
by t h eD a k o t aS a n d s t o n e .
may be t r a c e d i n o u t c r o p s o u t h e a s t w a r d
t h r o u g ht h eP l u m a s a n oB a s i nq u a d r a n g l ea n di n t ot h eM e s i t a
see. 35, T . 9 N.,
R.
19W.,
N o r t h w e s t o ft h es t u d y
Mesa,
de
it t h i n sc o n s i d e r a b l ya tt w ol o c a l i t i e s
Yeso q u a d r a n g l e ,a l t h o u g h
"
the
it is n o t
from t h eu n d e r l y i n gE n t r a d a .
e a s i l yd i s t i n g u i s h e d
s e c t i o nn e a rB l a c k
Cow S p r i n g st e r m i n o l o g yi n t o
and sec. 3 1 1 T . 8 N . ,
R.
18 W.
a r e a t o w a r dF o r tD e f i a n c ea n dB l a c k
t h i ss a n d s t o n eg r a d e sl a t e r a l l yi n t ot h eS u m m e r v i l l ea n d
B l u f fF o r m a t i o n sa n do v e r l i e st h eE n t r a d a .N o r t h w a r da n d
n o r t h e a s t w a r dn e a rT o d i l t oP a r k
intertonguewiththe
F o r m a t i o na n d
t h e s a n d s t o n ea p p e a r st o
Westwater CanyonMemberof
t h e Morrison
i s c o n s i d e r e d t o b ea ne o l i a nd e p o s i t
c o n t e m p o r a n e o u s w i t h t h ef l u v i a lM o r r i s o n( H a r s h b a r g e r ,
R e p e n n i n ga, n dI r w i n1, 9 5 7 ,
p. 50).
area s o u t h w a r d ,t h ec o n t a c tb e t w e e nt h e
From t h eL u p t o nA
, rizona,
C o w S p r i n g sa n dt h e
u n d e r l y i n gE n t r a d ab e c o m e su n i d e n t i f i a b l e( H a r s h b a r g e r ,
R e p e n n i n ga, n dJ a c k s o n1, 9 5 1 ) .
term Cow S p r i n g s - E n t r a d a
Hackman a n dO l s o n( 1 9 7 7 u) s e d
( J c s e ) f o rt h i si n t e r v a li nt h eZ u n i
area:
11
the
In the Los Pilares area immediately south the
of Mesita de
Yeso quadrangle the basal Zuni Sandstone commonly has a thin
conglomeratic zone, 1-3. ft thickt resting on an irregular
surface.
The irregular surface is locally developed ona 4-ft-
thick, greenish-gray siltstone and very fine grained silty
sandstone that
siltstone
--
--
in contrast tothe underlying reddish-brown
is indistinctly bedded and noncalcareous.
As no
break in deposition is apparent at the reddish-brown/greenishgray boundary, the unit is considered to be all Rock Point.
The
base of the Zuni and, hence, the Upper Triassic-Upper Jurassic
unconformity is representedby the irregular surface and the
conglomerate.
The
remainder
of
the
Zunit
which
measures
90 ft
in
composed of white to pinkish-gray fine-grained sandstone.
allt
is
Its
most distinguishing characteristic is the large-scale sets of
high-angle festoon and planar crossbedding which indicate an
eolian origin.
Crossbed dip directions are to the southwest
generally with 220-240 dips.
A zone of dark-brown, ferruginous
concretions with crossbed laminations passing through them forms
a prominent break 60 ft above the base.
As previously mentioned
local variations in thickness are considerable, and the unit
contains
some
red
beds
near
the
townsite
southeast corner of the Plumasano Basin quadrangle.
of
Atarque
Because much
of the Triassic sequence and the Cretaceous sequence is shale,
wherever a thick, resistant Jurassic sandstone is present local
12
and
in
th
p r o m i n e n c e sl i k e
L o s P i l a r e s a n d Mesa C o l o r a d o( A t a r q u eL a k e
quadrangleh
) a v ed e v e l o p e d .
2 i s a c o m p o s i t es t r a t i g r a p h i c
Fig.
column f o r t h e M e s i t ad eY e s o - L o sP i l a r e s
area.
The C r e t a c e o u sr o c k sc o n s i s t ,i na s c e n d i n go r d e r ,o ft h e
m a i nb o d yo ft h eD a k o t aS a n d s t o n e ,a ni n t e r t o n g u e dD a k o t a
Rio S a l a d ot o n g u eo ft h e
S a n d s t o n e - M a n c o sS h a l es e q u e n c e ,t h e
T r e s H e r m a n o sF o r m a t i o n .
M a n c o s ,a n dt h ec o a l - b e a r i n g
The rocks
c a l l e dt h em a i nb o d yo ft h eD a k o t aS a n d s t o n e
are t h e marine,
m a r g i n a lm a r i n e ,a n dn o n m a r i n er o c k st h a t
make u p t h e l o w e s t p a r t
of t h eC r e t a c e o u ss e q u e n c ei nw e s t - c e n t r a l
C o b b a na, n dL a n d i s ,
composedof
1980).
is
I nt h es t u d ya r e at h eD a k o t a
or
a b a s a l , c r o s s b e d d e d ,f l u v i a ls a n d s t o n e
c o n g l o m e r a t eo fv a r y i n gt h i c k n e s s ,
c o n t a i n i n gc a r b o n a c e o u s
a p a l u d a ls h a l es e q u e n c e
s h a l e a n dv e r yt h i nc o a l
m a r g i n a l - m a r i n es a n d s t o n e st h a t
( F i g . 2).
N e w Mexico(Hook,
form t h eu p p e r
beds, a n d
25 f t o f t h e u n i t
Root t u b e s were n o t e da tt h et o po ft h ef l u v i a l
sandstoneinthe
SE
1/4, N E 1/4 s e c . 1 7 , T. 7 N.,
R. 1 7 W.
F o s s i l sc o l l e c t e dl o c a l l yi nt h eu p p e rm a r i n es a n d si n c l u d e
bivalves Pycnodonte
cf.
the
P. k e l l u m i a n d E x o g y r a l e v i s a n d
is
T u r r i t e l l a sp. a n dv a r i o u so t h e rg a s t r o p o d s T
. h eD a k o t a
o v e r l a i n by t h e lower p a r t o f
t h e Mancos S h a l e , a 2 0 - f t - t h i c k
a r e n a c e o u s s h a l e t h a t i s e x p o s e d i n t h e N E 1 / 4 sec. I, T. 6 N.,
R.
18 W.;
e l s e w h e r e i t i s c o v e r e do ru n r e c o g n i z a b l e T
. h i ss h a l e
t o n g u e is p r o b a b l ye q u i v a l e n ti n
w h i c hh a s
part t ot h eC l a y
a t y p es e c t i o nd e s i g n a t e di nt h eL a g u n a ,
Mesa Tongue,
N e w Mexico,
a r e a ( a s d om o s to ft h ei n t e r t o n g u e dD a k o t a - M a n c o su n i t s[ L a n d i s ,
D a n ea, n dC o b b a n1, 9 7 3 1 )H
. o w e v e rb, e c a u s eo tfh ep i n c h o uot f
a nu n d e r l y i n gs a n d s t o n et o n g u e( t h eC u b e r o )
13
a few miles s o u t h w e s t
14
Fig. 2 .
Composite stratigraphic column for the Mesita de Yeso-Los Pilares area
scale
(ft.1
-
Bidahochi
Fm
Rio
/"l
DDOO.*DI.
%%%R%B.%oI:
75
%o .pale olive,
very fa to fn grained, pale^ -yellowish-gray
burrowed, com. bioturb., cross-bedded in upper parts; thin shale
com.; fossiliferous in mid
& up parts
-
3Whitewater
Arroyo
Tongue l25
xxxxx
E. trigeri (Coquand) present
Shale, gray to med. dark gray;
especially in middle part, selenite xtals; 15" thick white to
orange bentonite bed near the middle, but is poorly exposed he
-
Paguate
Tongue I5O
very fn to fn grained, pale yellow gray to grayish orange; com
E. cf-E. kellumi and~largespecimens.of~E.levi:
fOSSiliferOus at top,
SS,
Lower part
of
Mancos. 175
~
Sh, gray; calc.
sh and calcarenite beds30-35 ft. above base are
newberryi
(Stanton) fragments; numerous thin bentonitic
rich inE.
beds below and in'calc. beds are white
to orange weathering
Salado
Twowells
Tongue
Ss and cgl.; ss rich in lithic fragments; cgl composed of vesicular
basalt, basaltic andesites, rhyodacite, other volcanics, and qtzit
Arenaceous sh; poor exposures
-
very fn to fn grained, grayish orangeto pale yellow brown;
com.
flaggy bedded esp.near top; small burrows present in upper part
Ss.
200-
I
Dakota 225
-
Sh, gray to brownish gray; paludal; thin
ss and arenaceous sh beds
locally; carbonaceous zones with very thin coaly beds present
middle
ss
tolow mea .grained, sravish orange
fluvial; locally conglomeratic
at base
S s , fn
"
Ss, white to
dipping high
conglomerate
where thinit
'[
Rock
350
-
n
vellowish brn;
-to pale
-
pinkish gray, very
fn grained; thick sets of southwest
angle planar and festoon cross beds; locally
a pebble
zone at base; variation in thickness is considerab
may be greenish gray and more poorly cemented
...,...,...
..,.
:;.' . .
.,._.,.
...
::::::
. ...:..........
,:
.....'
.....,..
. .....
.:..,;...
:.;.
. ..,...
.:.:.:.
I .
r
siltst, lower very
fn grained ss with siltst, reddish
flat bedded; locally3' to 4 ' greenish gray zone
at top
Ss and
Point
Chinle
Fm
(section
increaslng
,,I,,
c
:
grain
size
not
me.asured)
+8
T"J
*,:;..:....>.: burrows
carbonaceous
XXXXxbentonite bed
brown,
cross-bedded
o f L a g u n a r t h e t e r m C l a y Mesa c a n n o t b e e x t e n d e d i n t o t h e s t u d y
a r e a a n dh e n c et h e
i s u s e dh e r e
i n f o r m a l term " l o w e r p a r t o f
(see Hook,Cobban,andLandis,
O v e r l y i n gt h e
1980).
s h a l e i s t h e P a g u a t eT o n g u eo ft h eD a k o t a
of a 2 0 - f t - t h i c k ,m a s s i v e r
S a n d s t o n e :t h eP a g u a t ec o n s i s t s
t h a t commonlyhas
c r o s s b e d d e d ,c o a r s e n i n g - u p w a r ds a n d s t o n eu n i t
fossil-hashzoneat
t h e t o pc o m p o s e d
of Exogyra l e v i s a n dP y c n o d o n t e
almost e x c l u s i v e l y o f s h e l l s
-
The u n i tc h a r a c t e r i s t i c a l l yw e a t h e r st o
s m a l lc l i f ff o r m e r ,b u to u t c r o p s
T. 7 N.,
i t is g e n e r a l l y a
are v e r yr e s t r i c t e d
wherelargespecimens
D a k o t a ,a st h el o w e r
on t h i s
1/4 sec. 36,
of E. l e v i s h a v e b e e n
u n i t merges w i t ht h em a i nb o d yo f
c o l l e c t e d .N o r t h w a r dt h e
p a r t of t h e M a n c o sS h a l ep i n c h e s
t h e v i l l a g e o f Two Wells, 1 4 m i d u e n o r t h o f
localitiesof
a light-tan
Good o u t c r o p s may b ef o u n di nt h eS e
R. 18 W.,
i n the
may a l s o b e p r e s e n t
or p a l e - g r a y i s h - o r a n g ec o l o r .T o p o g r a p h i c a l l y
quadrangle.
a
cf. P. k e l l u m i .L a r g eb r o w n
f e r r u g i n o u s / c a l c a r e o u sc o n c r e t i o n s
upper part.
t h e M a n c o sS h a l e "
the
out.
Near
Zuni, a t t h e type
t h e T w o w e l l s T o n g u eo ft h eD a k o t aa n dt h e
Whitewater ArroyoTongue
of t h e Mancos, t h e P a g u a t e
is n o t
present as alithologic unit distinct from the main body ofthe
D a k o t aS a n d s t o n e( H o o k ,C o b b a n ,a n dL a n d i s ,1 9 8 0 ) .
T h eW h i t e w a t e rA r r o y oT o n g u eo f
t h e M a n c o sS h a l eo v e r l i e s
the
P a g u a t eT o n g u et h r o u g h o u t h eZ u n iB a s i n .T h en a m ew a sp r o p o s e d
by Owen ( 1 9 6 6 )w h oa p p l i e d
i t t o a " w e l l d e f i n e d rp e r s i s t e n t
t o n g u e of m a r i n e s h a l e s e p a r a t i n gt h eT w o w e l l s[ T o n g u e ]f r o m
rest of t h eD a k o t aS a n d s t o n e
S a nJ u a n
i n t h es o u t h w e s t e r n
B a s i n " ( a n di nt h eG a l l u pS a ga r e a ) .
the
p a r t of t h e
A t y p es e c t i o n
was
15
~
designated in Whitewater Arroyo in
s e c . 1 7 o f T. 1 2 N.,
R. 1 9
W.1
n e a r t h e v i l l a g e o f Two Wells, w h e r e i t i s 80 f t t h i c k a n d
d e s c r i b e d a s a g r a yt oo l i v e - g r a y ,s i l t y ,o y s t e r - b e a r i n gs h a l e .
I t c r o p s o u t o n l y s p a r i n g l y i n t h e p r e s e n t s t u d ya r e a w h e r e i t
c o n s i s t s of a n e s t i m a t e d 60 f t of medium- t o d a r k - g r a y
I
s h a l ea n dc o n t a i n st h er e l a t i v e l yl a r g eo y s t e rE x o g y r at r i g e r i
I
(Coquand) i n i t s m i d d l ep o r t i o n .A l s ov e r yn e a r
distinctive white-
I
w e l l e x p o s ehde r e .
t h eW h i t e w a t e rA r r o y oT o n g u ea n d
west o nt h eV e n a d i t o
R.
1 9 W.,
t h e m i d d l e is a
t o o r a n g e - w e a t h e r i n g1 5 - i n c h - t h i c kb e n t o n i t e
b e d t h a t i s l h o w e v enr ,o t
N.,
Good e x p o s u r e s of
t h e b e n t o n i t eb e do c c u rt ot h e
Camp q u a d r a n g l e i n t h e
w h e r e i t i s p r o t e c t e d by a c o v e r of T w o w e l l s
18 m i t o
t h es o u t h w e s to nt h eT w e n t y t w oS p r i n gq u a d r a n g l ea n d7 5
east on D-Cross Mountain where
(HookC
, o b b a n a, n dL a n d i s ,
i t may b e o n l y 8 i n c h e s t h i c k
t h e D a k o t aS a n d s t o n ec r o p so u ti n
e a s t e r na n dn o r t h e r np a r t so f
20 f t i n t h i c k n e s s b u t
t h e q u a d r a n g l ew h e r e
i s g e n e r a l l y less.
f o u n da l o n gt h em o n o c l i n ei nt h en o r t h e r np a r t
T h eT w o w e l l sc o n s i s t so f . 1 )
i t may r e a c h
Good o u t c r o p s may be
of t h e q u a d r a n g l e .
i s l o c a l l yb u r r o w e d
a t t h et o p :t h i sb a s a lp o r t i o nw i t h
t h i n ,b e n t o n i t i cc l a yo v e r l y i n g
T. 6 N.,
R.
the
a b a s a l ,4 - f t - t h i c k Iv e r yf i n e
f l a t - t o w a v y - b e d d e ds a n d s . t o n et h a t
a n dv e r yf o s s i l i f e r o u s
m i to the
1980).
TheTwowellsTongueof
secs. 6 a n d7 ,
7
NE 1 / 4 sec. 30, T.
S a n d s t o n e .T h eb e n t o n i t eb e dh a sa l s ob e e nr e c o g n i z e d
grained,
fissile
is w e l l e x p o s e da l o n g
1 7 W.:
a
NM-32
in
2) anoverlyinggrayshaly
s a n d s t o n eo fv a r i a b l et h i c k n e s s ,g e n e r a l l yp o o r l ye x p o s e d ,t h a t
is a l s ol o c a l l yf o s s i l i f e r o u s :a n d
3 ) a nu p p e r ,f i n e -
m e d i u m - g r a i n e d ,p a l e - y e l l o w i s h - g r a y ,c r o s s b e d d e ds a n d s t o n e l
16
t o lower-
characteristicallywiththinlyinterbedded
wavybedding
i s a l s o c h a r a c t e r i s t i co f
s h a l e a n dc l a y
t h i s u p p e rs a n d s t o n e .T h e
T w o w e l l s i s w e l l d i s p l a y e d on t h e q u a d r a n g l e b o u n d a r y i n
1 / 4 s e c . 3 5 , T. 8 N.,
t h e SW
An u n c h a r a c t e r i s t i c a l l y m a s s i v e ,
R. 1 8 W.
i s e x p o s e di nt h e
s t r u c t u r e l e s s ,1 2 - f t - t h i c ks e c t i o no fs a n d s t o n e
SW 1 / 4 NE 1 / 4 s e c . 2 9 , T. 7
clasts:
N.,
R. 1 7 W.,
formingtheupperpart
o ft h eT w o w e l l s .
FossilsintheTwowellsconsistalmostexclusivelyof
,
Pycnodonk
t ee l l u mfir, a g m e n otEsfx o g y rt rai g e(rC
i o q u a n da) n, d
~
small s p e c i m e n s of E x o g y r al e v i s .E v i d e n c e
of b u r r o w i n ga n d
b i o t u r b a t i o n i s common t h r o u g h o u t :t h eb u r r o w si n c l u d e
I
OphiomorphB
a .o t hTew o w e l al snt dhPea g u a tTeo n g u e s
may
r e p r e s e n tm i n o rr e g r e s s i v ep u l s e si nt h eD a k o t a - M a n c o s
I
t r a n s g r e s s i v es e q u e n c e .
I
f e a t u r e s ,s u c ha so p p o s e dc r o s s b e d d i n g ,t h a ts u g g e s td e p o s i t i o n
T h e T w o w e l l si np a r t i c u l a rc o n t a i n s
i n a t i d a l c h a n n e le n v i r o n m e n t .
T h e R i o S a l a d oT o n g u eo ft h eM a n c o sS h a l er e p r e s e n t s
r e t u r n t o open-marine,
a rapid
deeper water c o n d i t i o n s o r a n i n t e r r u p t i o n
of T w o w e l l s .T h eR i o
i ns e d i m e n ts u p p l yf o l l o w i n gd e p o s i t i o n
S a l a d oc o n s i s t so fu pt o2 4 0
f t o fm e d i u m - g r a ya n dg r a y i s h - b r o w n
s h a l e ,c a l c a r e o u ss h a l e ,a n dt h i nc a l c a r e n i t e sw i t ha n
i n t e r b e d d e ds h a l ea n dv e r yf i n eg r a i n e ds a n d s t o n es e q u e n c ea t
t o p where i t g r a d e si n t ot h eo v e r l y i n g
ThenameRioSaladoTongue
T r e s HermanosFormation.
is p r o p o s e d i n
Hook, M o l e n a a r ,
I t i s d e f i n e d a s t h es h a l e
a n dC o b b a n( 1 9 8 2 i, np r e p a r a t i o n ) .
t o n g u el y i n gb e t w e e nt h eT w o w e l l sT o n g u eo ft h eD a k o t aS a n d s t o n e
a n dt h eA t a r q u eS a n d s t o n e
Member o f t h e
17
T r e s H e r m a n o sF o r m a t i o n
the
is
( o r A t a r q u eS a n d s t o n eF o r m a t i o nt ot h es o u t h w e s t )a n d
c o e x t e n s i v ew i t ht h e s e
two u n i t s .
The t h i nc a l c a r e n i t ea n dc a l c a r e o u ss h a l eb e d s
30-40
f t a b o v et h eb a s eo f
t h a t occur
t h e R i oS a l a d or e p r e s e n tt h e
e q u i v a l e n to ft h eB r i d g eC r e e kL i m e s t o n e
Member o f t h e G r e e n h o r n
F o r m a t i o n( H o o kC
, o b b a na, n dL a n d i s1, 9 8 0 )T
. h eb e d s
b er e c o g n i z e d
may o f t e n
a t a d i s t a n c ei no u t c r o pb e c a u s et h ey e l l o w -
w e a t h e r i n gc a l c a r e n i t e ss t a n do u ti nc o n t r a s tt ot h et y p i c a l l y
beds a r ew e l l
g r a y MancosShale.The
i n t h e SW 1 / 4 s e c . 6 , T. 6 N.,
R.
e x p o s e dj u s t
1 7 W.,
west o f NM-32
where the thin
calcarenitescontainabundantfragmentsofPycnodontenewberryi
t h e s e b e d s i s r e l a t e d t o t h ev e r y
( S t a n t o n ) .D e p o s i t i o no f
C e n o m a n i a n( G r e e n h o r n )t r a n s g r e s s i v e
late
was
maximum, a n e v e n t t h a t
marked by t h e d e p o s i t i o n o f l i m e s t o n e b e d s t h r o u g h o u t m o s t o f t h e
W e s t e r nI n t e r i o rs e a w a y .T h eb e d sf o r mi m p o r t a n tm a r k e r
t h e g u i d ef o s s i lP y c n o d o n t en e w b e r r y i
h o r i z o n s ,a n da l s o
( S t a n t o n )a p p e a r si na b u n d a n c e
a t o rj u s tb e l o wt h i si n t e r v a l
was c o l l e c t e di n
(Hook, a n dC o b b a n1, 9 7 7 )P. y c n o d o n t en e w b e r r y i
t h e N E 1 / 4 sec. 1, T. 6 N.,
B r i d g eC r e e kb e d s
may b er e c o g n i z e d
r e s i s t i v i t yk i c kt h e yp r o d u c e
I nt h es u b s u r f a c et h e
R. 1 8 W.
by t h e d i s t i n c t i v e
on t h ee - l o g ,w h i c h
is h e l p f u l i n
correlations.
About 100 f t a b o v et h eB r i d g eC r e e ke q u i v a l e n t ,l i m e s t o n e
c o n c r e t i o n sc o m m o n l y
well e x p o s e d h e r e .
the
appear i n t h e s e c t i o n , b u t t h i s z o n e
L o c a l l ya s s o c i a t e dw i t h
a m m o n i t e sMammites
cumminsi,
t h e c o n c r e t i o n s are
depressus, M. n o d o s o i d e s ,
and Neoptychites cephalotus,
Proplacenticeras
(see Anderson, 1982a).
Also, f o u n d l o c a l l y i n a s s o c i a t i o n w i t h t h e c o n c r e t i o n s a r e
18
is n o t
O s t r e a sp.,
V e n i e l l am o r t o n i ,B a c u l i t e s
o t h e rg a s t r o p o d s .T h i sp a r to f
sps.,
t h e Rio S a l a d o i s p r e s e n to n l yi n
secs. 21,
t h ee x t r e m ee a s t e r np o r t i o no ft h eq u a d r a n g l ei n
a n d3 3o f
7 N.,
T.
T u r r i t e l l as p .a n d
28,
a n d sec. 4 of T . 6 N.
The A t a r q u e S a n d s t o n e
is t h e term p r o p o s e di n
Member of t h e Tres H e r m a n o sF o r m a t i o n
Hook, M o l e n a a r ,a n dC o b b a n( 1 9 8 3i n
p r e s s ) f o rt h er e g r e s s i v ec o a s t a l - b a r r i e rs a n d s t o n eu n i tt h a t
o v e r l i e s t h e R i o S a l a d o T o n g u e o f t h e M a n c o s S h a l e a n da s s u c h
seaway f o l l o w i n g t h e
m a r k st h ef i r s tm a j o rr e g r e s s i o no ft h e
D a k o t a - M a n c o(sG r e e n h o r nt)r a n s g r e s s i o nT. h A
e t a r q uS
e andstone
Member a n d t h e o v e r l y i n g n o n m a r i n e C a r t h a g e
e q u i v a l e n tt ot h eA t a r q u eS a n d s t o n e
1 9 8 3 ,i np r e s s )a n dt h eM o r e n o
(Hook,Molenaar,andCobban,
H i l l F o r m a t i o n( M c L e l l a na n d
press) w h i c h a r e t h es t r a t i g r a p h i cn a m e su s e d
o t h e r s ,1 9 8 3 ,i n
west o ft h eM e s i t a
t h es o u t ha n d
Member a r e i n p a r t
to
de Y e s oq u a d r a n g l e( A n d e r s o n , ~
1982b).
A t t h e time t h eA t a r q u eS a n d s t o n e
s h o r e l i n eh a da s s u m e d
was d e p o s i t e d , t h e
a g e n e r a l NW-SE t r e n d i n t h i s a r e a a n d t h e
A t a r q u e Member p r o g r a d e d n o r t h e a s t w a r d i n t o t h e M a n c o s s e a w a y .
T h eA t a r q u e
i s a d i a c h r o n o u su n i tt h a tb e c o m e sy o u n g e rt ot h e
n o r t h e a s t .T h r o u g h o u t
i asin,
much o f t h e Z u n B
formingunitandconsistsof
a p p e a r si nm o s to u t c r o p s
t r a n s i t i o n a lz o n e
t of i n eg r a i n e d :
it is a c l i f f -
a l o w e rf l a t - b e d d e ds a n d s t o n ew h i c h
a s t h e f i r s t m a s s i v eu n i to v e r l y i n gt h e
a t t h e base:
i t c o a r s e n su p w a r df r o mv e r yf i n e
2 ) a m e d i a l , f i n e - g r a i n e d ,s h a l yu n i to fv a r y i n g
t h i c k n e s s ,b u tg e n e r a l l y1 0 - 2 0
ft:
a n d3 )a no v e r l y i n g ,l o w e r -
t ou p p e r - f i n e - g r a i n e d ,c r o s s b e d d e ds a n d s t o n e ,f o s s i l f e r o u sa t
19
the
t o p ,t h a t
i s 14-20 f t t h i c k .U n i t s
1) a n d 3 ) a r e similar t o t h e
lower a n du p p e rs h o r e f a c es a n d s t o n e so fM o l e n a a r( 1 9 7 3 ) T
. he
i s t h o u g h tt oh a v eb e e nd e p o s i t e do f f s h o r e
l o w e rs h o r e f a c eu n i t
b e y o n dt h ez o n ew h e r ew a v ea c t i o no rl o n g s h o r ec u r r e n t s
t h e u p p e rs h o r e f a c e
i n f l u e n c e ds e d i m e n t a t i o n .D e p o s i t i o no f
u n i tp r o b a b l yt o o kp l a c ei nt h ez o n ew h e r el o n g s h o r ec u r r e n t s
were a c t i v e .B u r r o w s ,i n c l u d i n gO p h i o m o r p h a ,a r e
l o w e rf l a t - b e d d e du n i ta n d
common i nt h e
l e s s common a b o v e .
I na d d i t i o nt ot h e s et h r e eu n i t s
on t h i sq u a d r a n g l ea n d
of w h i t e t o v e r y p a l e o r a n g e ,
e a s t w a r d ,a nu p p e ru n i tc o m p o s e d
a small b u t
u p p e r - f i n e - g r a i n e d !c r o s s b e d d e ds a n d s t o n ef o r m s
c o n s p i c u o u s c l i f f t h a t r i s e s a b o v e a small b e n c hd e v e l o p e do nt h e
u p p e rs h o r e f a c eu n i t( F i g .
u p p e r m o s ts a n d s t o n e
3).
T w e l v e miles t o t h e west t h i s
is p r e s e n ta s
a n o n m a r i n eu n i t ,
d i s t r i b u t a r yc h a n n e ls a n d s t o n e( A n d e r s o n ,1 9 8 2 b ) ,a n d
i n c l u d e dw i t ht h eo v e r l y i n gM o r e n o
n a t u r e( n oc l a y
c l a s t s , n or i p p l em a r k s ,
r e l a t i v e l yw i d e s p r e a d ,u n i f o r md e p o s i t .
On t h e Mesita
is m o r em a r i n ei n
etc.) a n d i s a
T h e t o p is commonly
is o v e r l a i n by a p a l u d a l s h a l e .
b u r r o w e da n dr o o tp e n e t r a t e da n d
The t h i c k e rA t a r q u es e q u e n c e
was
H i l l Formation.
d eY e s oq u a d r a n g l e ,t h i sw h i t eu p p e rs a n d s t o n e
a fluvialor
h e r e p r o b a b l yr e p r e s e n t s
s t a n db e t w e e nh e r ea n dt h eA t a r q u eS a n d s t o n eo u t c r o p s
a shoreline
12 m i to
t h e west, w i t h a r e s u l t a n t b u i l d - u p o f t h e u p p e r s h o r e f a c e u n i t .
T h eA t a r q u eS a n d s t o n e
Member ( p r e s e s n tu s a g e )c o r r e s p o n d s
t h e L o w e r G a l l u p , o r t h e A t a r q u e Member o f t h e G a l l u p , of
M o l e n a a r( 1 9 7 3 ) :h ea l s o ,h o w e v e r ,i n c l u d e dt h eo v e r l y i n g
n o n m a r i n ec a r b o n a c e o u ss h a l e s ,f l u v i a lc h a n n e ls a n d s t o n e s ,a n d
t h i nc o a l
beds i n t h i s
member.
T h ef a u n a le v i d e n c ep r e s e n t e d
20
to
i n Hook,
Molenaar,andCobban
(1983, i n p r e s s ) p o i n t s t o
a
s i g n i f i c a n ta g ed i f f e r e n c eb e t w e e nt h eA t a r q u ea n dt h eG a l l u p .
t h e A t a r q u ea sh a v i n gb e e nd e p o s i t e dd u r i n ga n
T h e yr e c o g n i z e
e a r l i e r r e g r e s s i v ec y c l et h a n
s e p a r a t e df r o mt h eG a l l u p
t h e G a l l u pS a n d s t o n ea n da sb e i n g
by t h eP e s c a d oT o n g u e
of t h e Mancos
S h a l ea n dt h ea s s o c i a t e du n d e r l y i n gm a r i n es a n d s t o n eu n i tf o r
w h i c ht h e yp r o p o s et h en a m e
F i t e R a n c hS a n d s t o n e
Member o f t h e
(see Fig. 3 ) .
Tres H e r m a n o sF o r m a t i o n
ThePescadoTongue is not present on the Mesita de Yeso
i s a ne r o s i o n a l
I t s s o u t h w e s t e r n m o s to c c u r r e n c e
quadrangle.
r e m n a n ta p p r o x i m a t e l y
4 m i t o t h e e a s t on t h e ShoemakerCanyon
Southeasq
t u a d r a n g l eT
. h eu n d e r l y i n g v, e r yt h i n F
, i t eR a n c h
S a n d s t o n e Member e x t e n d s a l i t t l e f a r t h e r s o u t h w e s t a n d c o m e s
w i t h i n 3 m i o ft h e
Mesita d e Yeso b o u n d a r y (see F i g .
a u t h o r so ft h er e d e f i n e d - T r e sH e r m a n o sp a p e r
1).
The
(Hook,Molenaar,and
of t h eP e s c a d o
Cobban, 1983, i np r e s s )s t a t e dt h a tt h ep r e s e n c e
Tongue of t h e M a n c o sS h a l ed e t e r m i n e st h ea r e ai nw h i c ht h e
H e r m a n o sn o m e n c l a t u r es h a l l
Tres
were,
be u s e d .L a n d w a r de q u i v a l e n t s
a sp r e v i o u s l ym e n t i o n e d ,d e s i g n a t e d
a s t h eA t a r q u eS a n d s t o n ea n d
t h e Moreno H i l l F o r m a t i o n .T h ep o i n t
of n o m e n c l a t u r ec h a n g e
Q
limit o fm a p p a b l eP e s c a d o .H o w e v e r ,i nt h ep r e s e n t
w o u l db et h e
studyextending
a r o u n dt h ee n d
o c c u r sw a s
t h e T r e s H e r m a n o sn o m e n c l a t u r es o u t h w e s t w a r d
of t h e t o p o g r a p h i c f e a t u r e u p o n w h i c h t h i s
more a p p r o p r i a t e .
deemed less c o n f u s i n ga n dp e r h a p s
T h i s c a r r i e s t h e name i n t o t h e e a s t - c e n t r a l p a r t
Y e s oq u a d r a n g l ea n dt h u s
I
limit
of t h e Mesita de
i t b e c o m e st h eq u a d r a n g l ei nw h i c ht h e
c h a n g ei ns t r a t i g r a h i cn o m e n c l a t u r e ' t a k e s
21
place.
T o bemore
22
f
Fig. 3.
Composite stratigraphic column for the Mesita
de Yeso--Shoemaker Canyon SE
quadrangle boundary area. Upper, dashed
part of section is present only
on Shoemaker CanyonSE quadrangle
scale
(ft.)
-
0-
Pescado
r";
Sh, med gray to
It brownish gray; numerous tnin
s s beds near
l..............
.I base
r
t;"-..;
25-
Transgr. marine s s ; v tn to lower meu grained;
burrows,
including
Ophiomorpha,
common
I
1 1-1
'
I
I
I
I
Carthage
H
Mbr
2rA
100-
II
I
I
.
,
Paludal sh .and fluvial channel
ss; carb zone between fluvial
channel s s and marine Fite Ranch member well exposed
2.5 mi
east of quad boundary inNE% sec 24, T. 7 N., R. 17 W.
I
-
I
-0
Fluvial channelss, fn to
clay clasts
lower
med
grained,
cross
bedded,
Paludal sh, arenaceous sh, and thin,gramed
tn
ss; 4 ft aDove
base
is
coal
zone
up
to 2 0 in
thick
with
medial
white
ash
bed;
s s 20 ft above base is commonly burrowed and root penetrated
with
ripple marks locally indicating an eastward paleo flow directio
Pl
I
penetrated
Atarque
ss
Mbr
I
Rio
Salado
Tongue
I
I
I
250-
Ss, very pale orange, upper fin grained, cross bedded; top is
root
grained
interval
(covered)
fine
Ss, lower
to
upper
fin
grained,
cross
bedded;
locally
fossiliferous
near LQ&X1( u pShale and arenaceous shale interval
Ss, very fn to fn grained, flat bedded; burrows including
Ophiomorpha present; (lower shoreface unit)
.............
...............
..,,,
increasing
grain size
<
(Section not measured)
8
.
.::.:.:.;'
.. burrows
cross-bedded
T7T-r root tubes
-coal
or carb. zone
L
.;:T::L:.'
;,*
clay clasts
-
s p e c i f i c e a s t of NM-32 a n d n o r t h o f t h e Q u a t e r n a r y b a s a l t f l o w
P l a i n s t h e Tres Hermanos n o m e n c l a t u r e is
e m a n a t i n gf r o mt h eN o r t h
u s e d ; w e s t o f NM-32 a n d s o u t h of t h e b a s a l t f l o w t h en a m e s
”
H i l l F o r m a t i o n w i l l b eu s e d
A t a r q u eS a n d s t o n ea n dM o r e n o
interval.
T h en o m e n c l a t u r ec h a n g ec o r r e s p o n d sw i t h
c o a l - f i e l dt e r m i n o l o g y .T h e
for t h i s
a c h a n g ei n
T r e s H e r m a n o so u t c r o p st h a te x t e n d
intotheeast-centralpartofthe
Mesita d e Yeso q u a d r a n g l e
d e f i n et h es o u t h w e s te d g eo ft h eG a l l u p - Z u n i
coal f i e l d .
Coal
o c c u r r e n c e s t o t h e s o u t h a n d w e s tare part of the Salt Lake Coal
field.
O v e r l y i n gt h eA t a r q u eS a n d s t o n e
Member o f t h e
F o r m a t i o n i s t h e c o a l - b e a r i n gC a r t h a g e
T r e s Hermanos
T h i s member was
Member.
d e p o s i t e d on t h e emergent c o a s t a l - p l a i n e n v i r o n m e n t f o r m e d
as the
I t c o n s i s t s o fp a l u d a la n dl a c u s t r i n es h a l e sw i t h
sea r e g r e s s e d .
t h i nc o a l sa n ds a n d s t o n e sa n df l u v i a lc h a n n e ls a n d s t o n e s .T h e
b a s a lp o r t i o n
i s p a l u d a ls h a l e :
r o o t - p e n e t r a t e dA t a r q u e
z o n e l i e s 3-7
t h e c o n t a c tw i t ht h eu n d e r l y i n g ,
Member is s h a r p .
Where p r e s e n t , t h e c o a l
f t a b o v et h eb a s ea n dc h a r a c t e r i s t i c a l l yh a s
i n c h - t h i c kw h i t ea s hb e dn e a rt h em i d d l e .
I n t h i sg e n e r a la r e a
o r m o r e ,t h i n ,f l a t - b e d d e d ,
t h e b a s a ls h a l ea l s oc o n t a i n so n e
b u r r o w e da n dr o o t - p e n e t r a t e ds a n d s t o n e s( F i g .
3).
-~
T h e s ef l a t -
an a i d i n identifying t h e top
b e d d e ds a n d s t o n e sh a v eb e e nu s e da s
o ft h eA t a r q u e ,b u t
a 2-
t h i s t o p is m o r e a p p r o p r i a t e l y p l a c e d a t
the
b a s e of t h ep a l u d a ls h a l e .
Most of t h e member h a s b e e n e r o d e d o f f t h e s o u t h w e s t t r e n d i n gh i g h l a n dt h a te x t e n d so n t o
r e m a i n i n g s e c t i o n i s a t B.M.
t h e q u a d r a n g l e .T h et h i c k e s t
7405 i n t h e S E 1 / 4 sec. 2 8 , T. 7 N.,
23
R.
1 7 W.:
a tt h i se x p o s u r ew h i c ha p p r o a c h e s
100 f t i n t h i c k n e s s ,
clasts, and
a f l u v i a lc h a n n e ls a n d s t o n ' ew i t hc l a yg a l l s ,r i p - u p
rests o nt h ep a l u d a ls h a l e .
c h a n n e l - s c o u rf e a t u r e s
TertiaryRocks
The l i g h t - g r a y a n d p i n k i s h - g r a y f l u v i a l s a n d s t o n e a n d
c o n g l o m e r a t eu n i tt h a to c c u r so n l yo nM e s i t ad e
Yeso i s h e r e
c o n s i d e r e d a s p a r to ft h eB i d a h o c h iF o r m a t i o n .
The conglomerate
is c o m p o s e dl a r g e l y
of v o l c a n i c s - v e s i c u l a r b a s a l t s , b a s a l t i c
a n d e s i t e s ,a n dr h y o d a c i t e st h a ts u g g e s t
a s o u r c ea r e ai nt h e
e a s t o f Quemado.
D a t i l , Mangas, o rG a l l oM o u n t a i n ss o u t ha n d
p r e v i o u s l ym e n t i o n e dt h eu n i t
b et h ee q u i v a l e n to f
o r may
may be i n p a r t d e r i v e d f r o m
t h e c o a r s e - g r a i n e dd e p o s i to f
As
similar
l i t h o l o g y t h a t i s p r e s e n t o v e r much o f t h e Z u n i P l a t e a u a n d
Santa Rita Mesa; the Santa
and150-200
R i t a Mesa d e p o s i t s 7 m i t o t h e s o u t h
f t higherinelevationarebeingdesignatedasthe
F e n c eL a k eF o r m a t i o nb yM c L e l l a na n do t h e r s( 1 9 8 2 ,i n
preparation).
ThenameBidahochiwas
f i r s tp r o p o s e db yR e a g a n( 1 9 2 4 )f o r
t h e c o n g l o m e r a t et h a to v e r l i e sC r e t a c e o u sR o c k si nt h eG a n a d o ,
A r i z o n a ,a r e aj u s te a s to ft h eH o p iB u t t e sv o l c a n i c
work
by
field.
McCaan ( 1 9 3 8 ) , Reiche ( 1 9 4 1 ) a, n d
Later
Hack ( 1 9 4 2 ) ,
e s t a b l i s h e d a c o r r e l a t i o nb e t w e e nt h eB i d a h o c h ia n dt h eT e r t i a r y
s e d i m e n t s of t h e u p p e r
L i t t l e C o l o r a d od r a i n a g ei nt h eZ u n i
B a s i n .T h o s es e d i m e n t si nt h eP i n e h a v e na r e ac o n t a i n
some
g r a n i t i c d e b r i s s u g g e s t i n g a s o u r c ei nt h eg r a n i t e - c o r e dZ u n i
M o u n t a i n s .I nt h ep r e s e n ts t u d ya r e aa n d
westward, t h ec o a r s e
Tertiarysedimentsarelargelyofvolcanicorigin,with
24
a minor
q u a r t z i t ec o m p o n e n tp r o b a b l y
( E o c e n e )w h i c h
d e r i v e d f r o mt h eB a c aF o r m a t i o n
i s l o c a l l yc o n g l o m e r a t i c .R e p e n n i n ga n dI r w i n
(1954) e s t a b l i s h e d a r e f e r e n c e s e c t i o n f o r t h e f o r m a t i o n
15 m i
e a s t o f t h e s e t t l e m e n to fB i d a h o c h i ,A r i z o n a ,a n dr e c o g n i z e d
t h r e e members:
a l o w e r ,l a r g e l yl a c u s t r i n e
member: a m i d d l e
v o l c a n i c member: a n da nu p p e r ,l a r g e l yf l u v i a l ,
t h eZ u n iB a s i nd e p o s i t sw o u l d
member:
seem t o c o r r e i a t e w i t h
Most of
t h e i r upper
member: h o w e v e r , t h e y a l s o m e n t i o n e d t h e p o s s i b i l i t y t h a t
s o u t h e a s t w a r d ,t o w a r dt h es o u r c ea r e a ,
time e q u i v a l e n t so ft h e
lower m e m b e r m i g h t b e r e p r e s e n t e d b y f l u v i a l d e p o s i t s
i
o f t h e u p p e r member.
a t t h eb a s e
COAL RESOURCES
The Mesita d e Yeso q u a d r a n g l e r a s p r e v i o u s l y m e n t i o n e d ,
e n c o m p a s s e s a s m a l lp o r t i o no ft h eG a l l u p - Z u n ic o a lf i e l d .
o u t c r o po f
Tres H e r m a n o sF o r m a t i o n
The
t h a t extendsintothe
c e n t r a l p o r t i o no ft h eq u a d r a n g l ed e f i n e s
t h e s o u t h w e s te d g eo f
of t h e
t h ec o a lf i e l d .T h i nc o a l sa r ep r e s e n tn e a rt h eb a s e
Tres Hermanos i n secs. 2 1 r2 8 ra n d
C a r t h a g e Member o ft h e
T.
7 N.,
R.
east-
33 of
1 7 W.
I n t h e SE 1 / 4 sec. 2 1a tt h ee a s tq u a d r a n g l eb o u n d a r y r
c o a lz o n e
l i e s 3 t o 4 f t a b o v et h e
c o n s i s t s of two 1 0 - i n c h - t h i c k
t h i c kw h i t ea s h
base o ft h ep a l u d a l
c o a l b e d ss e p a r a t e d
No a n a l y s e s were madeon
bed.
the
s h a l e and
by a 2-inch-
t h ew e a t h e r e d
similar^ s t r a t i g r a p h i c p o s i t i o n
samples: h o w e v e r ,c o a li n
a
t ot h es o u t h ,w a sr e p o r t e d
byCampbell
10 m i
(1981) t o b eh i g hv o l a t i l e
b i t u m i n o u s B r a n k .T h ec o a le x t e n d se a s t w a r df r o mt h i sp o i n t
a n do n l y
4 % of t h e sec.
t h e two 1 0 - i n c hb e d s :t h e
( 2 6 a c r e s ) i s l i k e l yt ob eu n d e r l a i nb y
sec. 2 1c o a lr e s o u r c e s
are t h u s
c o n s i d e r e di n s i g n i f i c a n t .
I n t h e e x t r e m e SE 1 / 4 sec. 28, a c o a lz o n ew a sr e c o g n i z e d
a p p r o x i m a t e l y 6 f t a b o v et h eb a s eo f
t h e p a l u d a ls h a l e :t h ec o a l
of g o o dq u a l i t y .
i s 1 2i n c h e st h i c k ,b a d l yw e a t h e r e d ,b u t
p r o b l e me x i s t s
i n c hw h i t ea s hb e d
i n c o r r e l a t i o nw i t ht h e
sec. 2 1 o u t c r o p a s t h e
i s n o tr e a d i l ya p p a r e n t .
t h ec o a le x t e n d se a s t w a r da n do n l ya b o u t
s e c t i o n is u n d e r l a i n by t h ec o a l .T h ec o a l
a r e t h u s c o n s i d e r e di n s i g n i f i c a n t .
26
A
Here a s i n
2-
sec. 211
4% ( 2 6 a c r e s ) o ft h e
r e s o u r c e s o f sec. 28
In sec. 33 slightly more than 20% of the area (130 acres) is
underlain by the coal-bearing member, but at few placesdid the
coal approach the 14-inch cut off usedin calculating bituminous
coal resources (U.S.G.S.
Bull 1450-B, 1976).
On "the point" in
the SW 1/4 sec. 3 3 , the coal zone is represented by a 2-ft-thick
upper-fine-grained flat-bedded sandstone containing much woody
trash and carbonaceous fragments.
The coal resources for this
section, and hence the quadrangle, are thus considered
insignificant.
27
REFERENCES
Anderson,
O r i n J.,
C a m p q u a d r a n g l e ,C i b o l aC o u n t y ,
B u r e a uo f
I
N e w Mexico:
N e w Mexico
Mines a n dM i n e r a lR e s o u r c e sO p e n - f i l e
Mines a n dM i n e r a l
Report 1 6 3 .
c o a l r e s o u r c e so fA t a r q u eL a k e
1 9 8 2 b rG e o l o g ya n d
q u a d r a n g l e ,C i b o l aC o u n t y ,
I
resources of V e n a d i t o
1 9 8 2 a 1G e o l o g ya n dc o a l
N e w Mexico:
N e w M e x i c oB u r e a uo f
Resources O p e n - f i l eR e p o r t1 6 7 .
1983 ( i n p r e p a r a t i o n ) , Review a n dR e d e f i n i t i o no f
N e w Mexico:
Z u n iS a n d s t o n e ,W e s t - C e n t r a l
Geology, Vol.
5.
r e s o u r c e s of t h e Dyke a n d
C a m p b e l l ,F r a n k ,1 9 8 1 ,G e o l o g ya n dc o a l
Cerro P r i e t oq u a d r a n g l e :
N e w MexicoBureau
M i n e r a l Resources O p e n - f i l e R e p o r t
D a v i s , G e o r g e H.,
of M i n e s a n d
144.
1 9 7 8 ,M o n o c l i n a lf o l dp a t t e r no ft h eC o l o r a d o
P l a t e a uG
: e o lS. O C .
D a v i s , G e o r g e H.,
N e w Mexico
Amer.,
Mem.
151.
a n d K i v e n , C h a r l e s W.,
1 9 7 5 ,S t r u c t u r e
map o f
f o l d s i n P h a n e r o z o i cr o c k so ft h eC o l o r a d oP l a t e a uT e c t o n i c
of A r i dL a n d sS t u d i e sa n dt h e
P r o v i n c eo fA r i z o n a :O f f i c e
D e p a r t m e n to fG e o s c i e n c e ,U n i v .o fA r i z o n a .
Hack, J. T.,
1 9 4 2 ,S e d i m e n t a t i o na n dV o l c a n i s mi nt h eH o p i
B u t t e sA
, r i z o n aB
: u lG
l e o lS. O C .
H a c k m a n , R. J., a n d O l s o n , A. B.,
Amer.
vol.
53.
of
1977, Geology and structure
t h e G a l l u p lo x 2O q u a d r a n g l e , N e w M e x i c oa n dA r i z o n a :
S. E n e r g yR e s e a r c ha n dD e v e l o p m e n tA d m i n i s t r a t i o n ,
981.
28
U.
Map I -
H a r s h b a r g e r , J. W., R e p e n n i n g , C. A., a n d I r w i n ,
1957,
J. H.,
S t r a t i g r a p h yo ft h eu p p e r m o s tT r i a s s i ca n dJ u r a s s i cr o c k so f
U. S. G e o l .S u r v .P r o f .P a p e r
t h eN a v a j oC o u n t r y :
H a r s h b a r g e r , J. W., R e p e n n i n g , C. A.,
andJackson,
291.
R.
L.,
- New
J u r a s s i cS t r a t i g r a p h yo ft h eN a v a j oC o u n t r y :i n
1951,
Mexico
G e o l o g i c a lS o c i e t yS e c o n dF i e l dC o n f e r e n c eG u i d e b o o k ,
pp.
1951,
95-99.
Hook, S. C.,
a n dC o b b a n ,
W. A., 1 9 7 7 , P y c n o d o n t e n e w b e r r y i
"
( S t a n t o n ) Common g u i d e f o s s i l i n t h e U p p e r C r e t a c e o u s o f
Mexico:
N e w MexicoBureau
Annual Report 1976-77,
Hook, S. C.,
C o b b a n , W. A . ,
of M i n e sa n dM i n e r a lR e s o u r c e s
pp. 4854.
a n dL a n d i s ,
E.
-
t h e i n t e r t o n g u e dD a k o t aS a n d s t o n e
1 9 8 0 , E x t e n s i o n of
R.,
M a n c o sS h a l et e r m i n o l o g y
N e w MexicoGeology,vol.
i n t o t h e s o u t h e r nZ u n iB a s i n :
no.
2,
3.
Hook, S. C.,
M o l e n a a r , C.
W. A.,
a n dC o b b a n ,
M.,
Stratigraphyandrevision
1983 ( i n press),
of n o m e n c l a t u r e o f u p p e r
Cenomanian t oT u r o n i a n( U p p e rC r e t a c e o u s )r o c k so f
c e n t r a l N e w Mexico:
R e s o u r c e sC i r c u l a r
Kelley,
New
V. C.,
1955,
N e w M e x i c oB u r e a uo fM i n e sa n dM i n e r a l
185.
Monoclineo
s tfh eC o l o r a d oP l a t e a uB
: ull.
G e o l .S o c i e t yo f
L a n d i s , E. R.,
west-
America, v o l .
D a n e , C. G.,
6 6 1 p.
789.
W. A.,
a n dC o b b a n ,
1973,
S t r a t i g r a p h i ct e r m i n o l o g yo ft h eD a k o t aS a n d s t o n ea n dM a n c o s
S h a l ew
, est-central
1372-J.1
N e w Mexico:
44 p.
29
U.
S.
G e o lS. u r v e yB u l l .
Maxwell, C. H.,
a n dN o n i n i ,
L.
1981: o r a lc o m m u n i c a t i o n
G.,
t o Z u n iT r i b a l
regardingtheiradmininstrativereport
Council.
McCann, F.
1 9 3 8 ,A n c i e n te r o s i o ns u r f a c ei nt h eG a l l u p - Z u n i
T.,
S e r i e s , vol.
: m e r i c a nJ o u r S
. c i e n c e5 t h
a r e a , N e w M e x i c oA
361 p. 260.
map of t h eF e n c e
M c L e l l a n ,M a r g u e r i t e ,a n do t h e r s ,1 9 8 1 ,G e o l o g i c
L a k eq u a d r a n g l eC
, i b o l aC o u n t y ,
S u r v .p r e l . i m i n a r y
I
1 9 8 3 ,( i n
N e w Mexico:
U. S. Geol.
map.
p r e s s ) , M i d d l eT u r o n i a na n dy o u n g e r
C r e t a c e o u sR o c k s ,n o r t h e r nS a l tL a k ec o a lf i e l d s ,C i b o l aa n d
C a t r o nC o u n t i e s ,
-
N e w M e x i c o t i n C o n t r i b u t i o n s t o mid-
C r e t a c e o u sp a l e o n t o l o g ya n ds t r a t i g r a p h y
2, Hook, S. C.,
compiler:
M i n e r a lR e s o u r c e sC i r c u l a r
I
of N e w M e x i c o ,p a r t
N e w M e x i c oB u r e a u
no.
of M i n e sa n d
185 ( i n p r e p a r a t i o n ) .
1 9 8 2( i np r e p a r a t i o n ) ,T e r t i a r yF e n c eL a k eF o r m a t i o n
o fw e s t - c e n t r a l
N e w Mexico:Branch
G e o l .S u r v . ,D e n v e r
M o l e n a a r , C.
of C o a lR e s o u r c e s ,
U. S.
Fed. Cen.
1 9 7 3 ,S e d i m e n t a r yf a c i e sa n dc o r r e l a t i o no ft h e
M.,
New
G a l l u pS a n d s t o n ea n da s s o c i a t e df o r m a t i o n s ,n o r t h w e s t e r n
in Four Corners Geologic Society Memoir
Mexico:
p.
Book, 1973,
85.
O'Sullivan,
R.
B.,
1 9 7 7 , T r i a s s i c R o c k si nt h eS a nJ u a nB a s i no f
N e w M e x i c oa n da d j a c e n ta r e a s :i n
- N e w M e x i c oG e o l o g i c a l
S o c i e t y2 8 t hF i e l dC o n f e r e n c eG u i d e b o o k ,p p .1 3 9 - 1 4 6 .
Owen, D.
E.,
1 9 6 6N
, omenclature
i nS a nJ u a nB a s i n ,
of D a k o t aS a n d s t o n e (. C r e t a c e o u s )
N e w M e x i c oa n dC o l o r a d o :A m e r i c a n
o fP e t r o l e u mG e o l o g i s t sB u l l . ,v o l .
30
50, no.
5 , p.
ASSOC.
1023.
Reagan, A.B.,
1924, Stratigraphy of the Hopi Buttes Volcanic
Field, Arizona:
Pan-American Geologist, vol. 411 p. 355.
Reiche, Parry, 1941, Erosion stages of the Arizona Plateau as
reflected in a headwater drainage area:
Plateau, vol. 13,
p. 53.
Repenning, C. A.,
and Irwin, J. G., 1954, Bidahochi Formation of
Arizona and New Mexico:
Geologists Bull., vol.
American Assoc. of Petroleum
38, p. 1821.
Repenning, C. A . , Lance, J. F., and
Irwin,J. H.,
stratigraphy of the Navajo Country:
1958, Tertiary
in New
Mexico
Geological Society 9th Field Conference Guidebook,
p 128.
Silver, Caswell, 1948, Jurassic Overlap in western New Mexico:
Bull Amer. Assoc. Pet. Geol.,
Silver, J. H.,
Poole, P. G., and
vol. 32, no. I, p. 68.
WilsonR. F.,
1972,
Stratigraphy
and origin of the Chinle Formation and related Triassic
strata in the Colorado Plateau region:
U.
S. Geol. Surv.
Prof. Paper 690.
Stricker, Gary, and Anderson, Orin J., 1983 (in preparation),
Geology and coal resources of northwest quadrant of Fence
Lake, New Mexico 30 x 60 min. quadrangle, 1:100,000
quadrangle, Cibola County, New Mexico:
New Mexico Bureau of
Mines and Mineral Resources Open-fileReport.
U. S . Bureau of Mines and U.
S. Geological Survey, 1976, Coal
Reource Classification System of the U. S. Bureau of Mines
and the U. S. Geological Survey:
1450-B.
31
U. S. Geol. Surv. Bull.
_"
DESCRIPTION
OF
"AP UNITS .
.
~
Alluvial deposits undifferentiated; clay, silt, sand,
and gravel in arroyos, floodplains and on gentle slopes.
I
Basalt flows; originating from centers to east in North
Plains lava beds; olivine tholeite in composition with
K-Ar age of 1.41 m.y. (Laughlin, Brookins, Damon, and
Shafiqullah, 1979).
. LTb
Kthc
Bidahochi Formation (Pliocene); light gray to
gray lithic sandstone and coarse conglomerate.
erate composed of vesicular basalt, basaltic
rhyodacite, other volcanic rocks,and minor
pinkish
Conglomandesite,
quartzite.
Carthage Member of Tres Hermanos Formation (Upper Cretaceous); paludal shale and mudstone, carbonaceous shale
with minor coal, and fluvial channe2. sandstone. Shales
are gray to light olive gray; carbonaceous zone
4-6 ft
above base locally has up20 to
in of coal in
2 beds
seperated by 2 in thick white ash bed. Maximum thickness
on quadrangle-100 ft.
Ktha Atarque Sandstone Member of Tres Hermanos Formation(Upper
Cretaceous); grayish orange to very pale orange very
fine to upper fine. grained marine sandstone; coarsens
upward; well indurated, generally massive, cliff former;
burmms present in lower and middle parts; fossiliferoussmall bivalves, in middle part; upper part strongly
cross-bedded predominantly of festoon type and is contrasted
by its lighter color. Maximum thickness on quadrangle
about 65 ft.
Kmr
Rio Balado Tongue M
of
ancos Shale (UpperCretaceous); medium to
dark gray and brownish gray marine shale, silty shale,
calcareous shale and calcarenite, with thin interbedded
sandstone at the very top; weathers to gentle or moderately steep slopes which are generally covered by colluvium,
talus, or landslide debris; base not exposed; calcarenite
beds and calcareous shale with an underlying zone containing abundant Pycnodonte newberryi. (Stanton) ocyAr abaut
3 5 ft above the base; calcareous zone is Greanhsrn Limestone (Bridge Creek Member) equivalent; upper
100 ft of
the tongue contains numerous limestone concretion zones;
associated with the concretions locally are the ammonites
Mammites depressus, Mammites nodosoides, Proplacenticeras
cuminsi, and NeoptYchites cephalotus; also found in this
association are Ostrea sp., various bivalves, Turritella
and other gastropods. .Thickness of tongue estimated at
2 4 0 ft.
Kdt
Twowells Tongue of Dakota Sandstone (Upper Cretaceous);
yellowish gray to pale olive, very fine to upper fine
grained, shallow water marine sandstone; lower part
very fine grained, commonly burrowed and bioturbated,
with these features continuing into the middle, shaly
part; upper part is cross bedded in thin sets and/or
wavy bedded with thin shale interbeds; locally fossiliferous in all parts, but mainly middle and upper; fossils
consist of Pynodonte kellumi, and small (relative to
those in the Paguate
Tongue)Exogyra levis; also found
in association with these in sec.
3 4 , T 8N., R 18W;, is
Exogyra trigeri (Coquand). Maximum thickness on quadrangle estimated at20-22 ft.
KmW
Whitewater Arroyo Tongue of Mancos Shale (Upper Cretaceous);
gray to medium dark gray marine shale; slope former,
base not exposed; near the middle is a 15 inch thick
white to orange weathering bentonite bed not well exposed
in this area; selenite crystals common; the relatively
large oyster Exogyra trigeri is locally abundant;
estimated thickness of unit 60
isft.
Paguate Tongueof-Dakota Sanstone (Upper Cretaceous);
pale yellowish gray to grayish orange, very fine to upper
fine grained, massive wel-l indurated, marine sandstone;
coarsens upward; low angle cross bedding in upper part;
small cliff former. Pycnodonte cf.E. kellumi and large
specimens of Exogyra levis locally abundant
at top especially
in SE$ sec. 3 6 , T 7N., R 18W.; large, brown, oblate concretions common in upper part; ripple marks noted in NWa
sec. 5, T 7N., R 17W., maximum thickness of unit,
20 ft.
Kml
Lower part of Mancos Shale (Upper Cretaceous); medium
gray arenaceous shale; marine; nowhere well exposed;
may be gradational into underlying Dakota Sandstone;
thickness, 20 ft.
Kd
Dakota Sandstone, main body (Upper Cretaceous); the marine,
' .
marginal marine, and nonmarine rocks that make up the ' lowest
part of the Cretaceous sequence in west-central New Mexico
(Hook, Cobban, and Landis, 1980). Base is fluvial channel
sandstone sequence of varying thickness, locally conglomeratic
at places a paludal shale forms the base; middle portion
mainly paludal shale with carbonaceous zones and minor coaly
lenses; upper third is marine sandstone, thinly bedded
and flaggy near top, locally fossiliferous- Pycnodonte cf.
P.
- kellumi, Exogyra levis, and TurritePla-%.; -estimated
thickness
r
~
ft.
100
Jz
Zuni Sandstone"(Upper Jurassic); white to pinkish gray, very
fine grained sandstone; thick sets"o€ -high angle planar and
festoon cross bedding indicate eolian origin; cross bed dIp
direction is southwest; pebble conglomerate zone at base In
the south-central boundary area rests on an irregular surface
formed on underlying Rock Point Member: silty, very fine ,
facies may be greenish gray and poorly cemented; 90 ft thick
1
at southern boundary..
.
_ _ . . - . _ _ __ _. _. .=
. ..," ...~
- "/
-." .
~
i
%_
~
~
"
Tiwr
Rock Point Member -of Wingate Formation. (Upper Triassic);
reddish brown, flat bedded, silty sandstone and sand,y siltstone; at south central boundary area of quadrangle a
pale greenish gray zone, lacking distinct bedding,. is present
at top of unit; irregular surface at top
of greenish gray
zone represents unconformity between Upper TriassicUpper Jurassic sediments; thickness 3 2 ft. Unit is not
mappable over most of the quadrangle.
TC
Chinle Formation (Upper Triassic); purple, maroon, reddish
brown, and gray mudstone, shale, siltstone, and sandstone;
in this area the upper part of Chinle is assigned to Petrified Forest Member; exposures poor and unit was not examined
in detail; estimated thickness locally, 800-1000 ft.
..
C o n t a c td, a s h e dw h e r ea p p r o x i m a t eoirn f e r r e d
/2-"
D
%
...
u
F a u ld
t ,a s h ew
d h e raep p r o x i m a t e llyo c a t e d ;
u p t h r o w ns i d e ,
D downthrownside
S y n c l itanrxeao
pi,cflaaselnh eo wdi ni rge c t i o n
b . 4
of p l u n g e ;d o t t e dw h e r ep r o j e c t e db e n e a t h
mapped
units
. . ....+
A n t i c l i n et, r a c eo of x i apl l a n es h o w l n gd i r e c t i o n
of p l u n g e d
; o t t e dw h e r ep r o j e c t e db e n e a t h
m o p p e du n i t s
M o n o c l ti n
r aec. e
. . . . ' . I
direction
of axial
plane
showing
of p l u n g e d
, o t t e dw h e r ep r o ~ e c t e db e n e a t h
mappedunits
s
NATIONALGEODETICVERTICALDATUM
1000-metre Unlversal Transverse Mercator grld tlcks,
1927 North II,erlcand'atum
zone 12, shownIn-blue
OF 1929
UTM GRlO AND 1972 MAGNETIC NORTH'
DECLINATION AT CENTER OF SHEET
4-
.
I
-
7.200
d
C
0
"
c
CI
>
-a
6,800
6,400
-
8.400
4
7,600
/Kd
-_ _ _ _ _ _ ---------d""
--Z"
-
QOI,
Kml
X c + fiwr
I
Q
,a,
,Kd
/
Kmw-
-
I
------"""_
+
Kml
\;lz""""""""-"""_""""~~
""
-------"""""""~-
hc
+- Siwr
"^
5.200
2- 7,200
-7-6,800
- 6,400
.-
6.000
-
5,600
5,200
/
-L
T h i c k n e s sp r o j e c t e d
in
fromdrillhole
sec 5 T 9 N . R IBW.
"
1
YlF
4.800
-.~"
4,400
.. ,
8,000
b.UUU
5,600
.
A'
8,400
7,600
o f beds
MESITA DE YESO, N. M
QUADRANGLE LOCATiON
A
C
S t r i k ea n dd i p
NEW MEXICO
,
Flne red dashed llnes lndlcate selected'fgnce llnes
8.000
3"
Y
I
1
Y
1
GEOLOGY A.ND GOA RESOURCESESITA DE YESO
DRANGLE,
OLA COU
~~
4,800
4,400
P€
i;
$
i
P€
- .
NEWMEXICOBUREAUOFMINE
A N DM I N E R A LR E S O U R C E S
O P E N - F I LREE P O R T
c
7,600
u
C
0
+
"
0
7,200
6,800
8,000
-
-
-
>
6,400
w
6.000
-_
5.600
-
a
-
5,200
171
8,400
8,400
-
-
-
i
1
B'
B
8.000
~.
~~
-
Kmw
Kd
d
""y"-"""-"""""""
JZ
""_
-
!
~""""""~"""~""""""""~
"----------- -----""
~~"""""""~""~"""
"-""""""
Kd
Xc+?wwr
ac
+Xwr
\J-z
1982
-
6.800
-
6,400
"
"
"
"
"
"
- 6,000
- 5.600
5,200
BY O R I N J. A N D E R S O N
,