NMBGMR Open-File Geologic Map 250
NEW MEXICO BUREAU OF GEOLOGY AND MINERAL RESOURCES A DIVISION OF NEW MEXICO INSTITUTE OF MINING AND TECHNOLOGY
Last Modified June 2015
Description of Map Units
Correlation of Map Units
107°15'0"W
0
0.5
2000
3000
4000
5000
0
6000
Qfao
Qsc
Qesc
Qayr, Qfayr
Qayh, Qfayh
Qaym, Qfaym
Qfay2
Qfay
Qay2
Qary, Qfary
Qahy, Qfahy
Qamy, Qfamy
12–0
ka
130–12
ka
780–130
ka
QTpwu
23–5.3
Ma
QTpa
QTpwm
33.9–23
Ma
488–444
Ma
542–488
Ma
o
o




o

o


 
h
Q
o

e
Tp

o
Q
e
QTp
h
fa



e
QTpe Qahm
Qay
Qfay?
Qf
288000 QTpa
Sediment transport direction determined from flute clasts
Qtr1b
Small, minor inclined joint, for multiple observations at one locality—Showing strike and
dip
Qtr2
Inclined fault—Showing dip value and direction

Spring, as shown on topographic maps or on general-purpose or smaller scale maps. Tail in
direction of flow.

Unused water well

Water well

A’
Qtr3
Cross section line and label
3655 000
Qtr5
ah
Qah
Qtge
m
Qfay
Qah
Qfah
QTpe
Qf1
Qahm
Qf1
Qahm
3654 000
Mapping Responsibilities
Williamsburg
NW
Cuchillo
Elephant
Butte
Qtro
Qaym

o o
Qfe
Qtr1a
Qtge Qfah
Qfe
Qay
QTpa
4
Recent (historical + modern) and younger alluvial fan deposits, undivided—
Recent fan alluvium (Qfah + Qfam) and subordinate younger fan alluvium (Qfay).
Rio Grande terrace deposits, undivided—Pebble-cobble gravel with sand
lenses in mostly thick-, tabular to lenticular beds, unconsolidated,
clast-supported, and imbricated to trough cross-stratified. Clast lithologies
include volcanic rocks, Cretaceous sandstone, Paleozoic carbonate and
jasperoid, quartzite, and granite. Matrix consists of over 55% rounded-quartz
grains. Locally subdivided into 7 deposits based on landscape position:
Younger and historical alluvial fan deposits, undivided— Younger alluvium
(Qfay) and subordinate historical alluvium (Qfah) deposited on alluvial fans.
Qf3
First or lowest Rio Grande terrace deposit—Weakly to moderately calcareous
and thin- to thick-bedded with occasional ripple cross-stratification, scarce
boulders, with brown to pale-brown (10YR 5-6/3) matrix. Locally subdivided
into two deposits: Qtr1a and Qtr1b, that were dated at < ~0.3 and 0.6–0.8 ka,
respectively (Mack et al., 2011). Deposit lacks significant soil development.
Tread height < 5 m above modern grade. Unit is 2.8 to perhaps 7 m thick.
Second or middle-lower Rio Grande terrace deposit—Pebbly to clayey sand
with common calcic horizons; correlative to terrace deposit II of Mack et al.
(2011) that was radiocarbon-dated at 5.3–8 ka. Tread height 3–6 m above
modern grade. Approximately 2–3 m thick.
Third or middle Rio Grande terraces deposit—Well-imbricated with
occasional trough cross-stratification, scarce boulders, with pale-brown (10YR
6/3) matrix. Varnish on 10–12% of clasts at surface. Stage I+ carbonate
morphology in upper 80 cm. Perhaps correlative to terrace deposit I of Mack et
al. (2011) that was radiocarbon-dated at < 12.4 ka. Tread height 5–8 m above
modern grade. 1.5–3 m thick.
Tsupw
Tsubf
Older alluvial fan deposits—Sandy, pebble-cobble gravel in thin- to thick-,
tabular to lenticular beds underlying surfaces graded to higher positions than
those of Qfay, unconsolidated to somewhat carbonate-cemented and massive to
weakly imbricated with brown to light-brown (7.5YR-10YR 4-6/3-4) matrix.
Moderate to strong varnish on clasts at surface. Approximately 3–4m thick.
Subdivided into 4 deposits along Palomas Creek:
Tsus
Deposits of alluvial fans graded to lowest terraces—Unconsolidated but
strongly calcareous, tabular, and massive to weakly imbricated with lightyellowish-brown (10YR 6/4) matrix. Features stage I carbonate morphology in
upperpart. Generally over 2 m thick.
Tsl
Deposits of alluvial fans graded to middle-lower terraces—Unconsolidated,
calcareous, tabular to lenticular, and weakly imbricated with brown (7.5YR 5/4)
matrix. Varnish on 60–70% of clasts at surface. Maximum thickness 4 m.
Qtfw
Fan terrace depoits graded to terraces in Cañada Honda—Sandy, fan gravel
interbedded with Qtgw terrace surfaces in Cañada Honda. Likely correlative to
Qf2 or Qf3 deposits. Perhaps up to 3.5 m thick.
Qtge
4
QTpe Qay
QTpe
Author(s) Mapping
Qay1
QTpe
Qahm
289000
QTp
33°0'0"N
Qay1
107°15'0"W
This geologic quadrangle was originally mapped using photogrammetry and field observations at a
scale of 1:12,000. This data was then generalized to a scale of 1:24,000 for the publication of this
7.5-minute quadrangle. The 1:12,000 GIS data is available on the New Mexico Bureau of Geology and
Mineral Resources website http://geoinfo.nmt.edu/publications/maps/geologic/home.html for download.
Koning
Qtp1
Qtp1a
Koning/Jochems
Saladone
Tank
Jochems
Palomas
Gap
Jochems/Koning
QTpa
Oldest or highest Rio Grande terrace deposit—High exposures of rounded
gravel containing exotic clasts such as quartzite, lacks obvious structure, and
likely represents thin-remainder of coarse channel-load of the ancestral Rio
Grande. Tread height 36–42 m above modern grade. Maximum thickness 3 m.
QTpac
First or lowest terrace deposit of Palomas Creek—Sandy gravel in medium to
thick beds, clasts include subequal proportions of pebbles and cobbles with
10–15% boulders. Locally subdivided into Qtp1a and Qtp1b with tread heights
7–16 m and 16–18 m above modern grade, respectively. 2–4 m thick.
QTpaf
Qtp1b
Qtp2
Williamsburg
Fifth or upper Rio Grande terrace deposit—Mostly unconsolidated, non- to
moderately calcareous, broadly lenticular, and well-imbricated to vaguely
trough cross-stratified, up to 5% boulders, light-brownish-gray to pale-brown
(10YR 6/2-3) matrix. Stage II+ carbonate morphology in upper 70–90 cm. Maybe
mantled by 0.5–2 m of Qes or Qesc. Tread height 24–30 m above modern grade.
2–6.8 m thick.
Second or middle-lower terrace deposit of Palomas Creek—Weakly calcareous
and thick- to very thick-bedded, with brown (7.5-10YR 4/3) matrix. Contains no
more than 3% boulders. Varnish on 20-30% of clasts at surface. Local
Fe-oxidation occurs on clast undersides in ~30 cm thick zones. Few preserved
soils (likely eroded). Well preserved along most of Palomas Creek in
quadrangle. Tread height 24–31 m
QTpe
7000 FEET
Skute
Stone
Arroyo
1 KILOMETER
Caballo
Apache
Gap
Upper coarse unit of the western piedmont facies of the Palomas
Formation—Sandy, pebble-cobble gravel in amalgamated, laterally continuous
channel-fill complexes 2–6 m thick, beds have scoured lower contacts and relatively
abrupt upper contacts. Unit defined where at least 65% coarse channel-fills, the
remainder being fine-grained extra-channel sediment. Both sediment types are
reddish-brown (5-7.5YR). Elevation of lower contact locally variable. 1–45 m thick.
Upper western piedmont facies of the Palomas Formation—Reddish-brown
(5-7.5YR), interbedded fine-grained sediment and subordinate to subequal, laterally
continuous, coarse channel-fill complexes. Upper and lower contacts transitional
with QTpwuc and QTpwm, respectively. Base taken at bottom of predominately
reddish sediment. Fine-grained, extra-channel sediment consists of clayey-silty
fine sand, very fine- to fine sand, and clay-silt. 10-40 m thick.
Transitional zone below the upper western piedmont facies of the Palomas
Formation—Predominately fine-grained sediment that is redder than QTpwm and
slightly less red than QTpwu. Lies gradationally between these two units, both in a
vertical and lateral sense. Fine sediment consists of silt-clay (silt>clay), very fine- to
fine-grained sand, and slightly silty-clayey sand. Subordinate coarse channel-fill
complexes and carbonate ledges up to 3 m thick. Up to 35 m thick.
Middle western piedmont facies of the Palomas Formation—Pink to light-brown,
very fine- to fine-grained sand, silty-fine sand, and silt in medium- to thick-,
tabular beds. Minor (5-15%) tongues of pebbly sand and sandy pebbles. Interfingers
with QTpa. Channel-fills locally fine upwards. 3–15% strongly cemented beds
(mostly medium- to thick-bedded) precipitated by groundwater and surface
springs. 75–100 m thick.
Coarse sediment in the middle western piedmont facies of the Palomas
Formation—Strata dominated by coarse channel-fills, as described in unit QTpwm,
that are thick enough to be mappable. 10–20 m thick.
Lower western piedmont facies of the Palomas Formation—Stacked, coarse
channel-fills composed of clast-supported, imbricated sandy gravel. Base is highly
transitional south of Mud Springs fault (over ~30 m), but on footwall of fault the
basal contact is gradational over 4–10 m or locally scoured (>1 m of scour relief).
100–115 m thick to north, appearing to thin to 50 m near Palomas Creek at the
Barney Iorio Fee #1 well.
Transitional base of the lower western piedmont facies of the Palomas
Formation—Interbedded clayey sediment and sand-gravel channel-fills. The clayey
sediment is mostly reddish and likely consists of clay, silt, and clayey-silty very
fine- to medium-grained sand. Variably cemented. Description is from Barney Iorio
Fee #1 well cuttings log. Sparse basalt fragments may occur in the upper part of the
unit. 5–35 m thick. Cross-section only.
Upper Santa Fe Group underlying the Palomas Formation (middle to upper
Miocene)—Units Tsupw and Tsubf, undivided. As described in the Barney Iorio
Fee #1 well log, the unit consists of interbedded clay and sandstone. Clays are
sticky and mostly pink at 632–802 ft, gray at 802–975 ft, and pink to red at 975–1165
ft. At 1170–2100 ft, the unit is harder (better cemented), exhibits gypsum
laminations, and may contain ash and/or carbonate beds. ~600 m thick.
Upper Santa Fe Group, western piedmont facies—Light-reddish-brown
(5YR6/3-4) strata, in medium- to thick-, tabular beds, composed of siltstone and
very fine- to fine-grained sandstone (about 50–70%), fine- to medium-grained
sandstone (~20%), and coarse channel-fills (increasing up-section from 10 to 25%).
The latter are ~2 m thick and consist of thin- to medium-, tabular beds composed of
pebbly sand or sandy pebbles. Maximum thickness 400 m.
Upper Santa Fe Group, basin-floor facies—Thin- to thick-, tabular beds of
light-reddish-brown to yellowish-red (5YR), very fine- to medium-grained sand
and clayey-silty sand. Minor (~5%) pebbly sand beds with clasts of aphanitic
(probably felsic) volcanic rocks, ~25% chert, trace to 10%, greenish sandstone
(Mesozoic?), ~5% granite, and ~5% gneissic (Proterozoic) clasts. Moderately to
well-consolidated; 5% well-cemented beds. 165–180 m thick.
Upper Santa Fe Group, silicified—Strongly silicified Santa Fe Group conglomerate
found in a sliver of the Hot Springs fault zone in the eastern partof the quad. Clasts
consist of poorly sorted, angular- to subangular pebbles and cobbles of aphanitic
volcanic lithologies, chert, granite, and metamorphic rocks. Matrix is replaced by
silica cement that is weak red (10R 4-5/) to reddish-brown (2.5YR 4-5/). Total
thickness >15 m.
Lower Santa Fe Group (Oligocene to middle Miocene)—Relatively well-cemented
Santa Fe Group consisting of volcaniclastic sandstone and conglomerates.
Correlative to the Hayner Ranch Formation and possibly to the Thurman
Formation. Described using exposures on the Skute Stone Arroyo quadrangle
(Koning et al., 2015). Estimated to be 1100 m thick using cross-section on Skute
Stone Arroyo quadrangle. Cross-section only.
Ordovician
Oma
Oml
Older alluvial fan deposits east of the Rio Grande—Sandy, pebble-cobble
gravel in thick-, tabular to broadly lenticular-beds underlying surfaces graded
to or below Qtr deposits east of the Rio Grande, weakly to moderately
consolidated, moderately to strongly calcareous, clast-supported, and massive
to moderately well-imbricated, with light-yellowish-brown (10YR5-6/4) matrix.
Commonly contains gastropods in sandier beds. >18 m thick.
Oepb
Quaternary-Tertiary Basin-Fill Units
Fourth or middle-upper Rio Grande terrace deposit—Medium- to
thick-bedded and well-imbricated, up to 15% boulders, sandy lenses composed
of 85–90% pebbles are common and up to 25 cm thick, light-yellowish-brown
(10YR 6/4) matrix. Capped by 35 cm thick stage II+ carbonate horizon. Tread
height 18–24 m above modern grade. 3.6–9 m thick
Fine-grained eastern piedmont faces of the Palomas Formation— Clayey to silty
sand with less than 40% gravel in thin- to medium-, tabular to lenticular beds,
unconsolidated and massive, gravel beds are clast- to matrix-supported and may
be imbricated with reddish-yellow (5YR 6/6) to pink (7.5YR 6-8/3-4) to very
pale-brown (10YR 8/2). Common buried soils feature stage I to II+ carbonate
morphology. Interfingers with basal QTpe to the east. 30–140 m thick.
Paleozoic Bedrock Units
Deposits of alluvial fans graded to middle terraces—Somewhat calcareous,
tabular, and massive to weakly imbricated with pinkish-gray (7.5YR 6/2) matrix.
Features stage I+ carbonate morphology in upper part, indicated by carbonate
coatings on up to 50% of clasts. Fe-oxide staining observed on up to 10% of
clasts. 2–3 m thick.
Deposits of alluvial fans graded to upper terraces—Poorly preserved deposit
observed near western quadrangle boundary, south of Palomas Creek.
Qfe
Tsu
Younger and recent (historical + modern) alluvial fan deposits, undivided—Younger
fan alluvium (Qfay) and subordinate recent fan alluvium (Qfah + Qfam).
Qf4
Paleo-Red Canyon alluvial fan deposits of the eastern piedmont facies of the
Palomas Formation—Siltstone, sandstone, and sandy, pebble-cobble-boulder
conglomerate in multi-story, thin- to thick-, tabular to lenticular beds, moderately to
strongly consolidated, commonly carbonate-cemented, mostly clast-supported, and
massive to imbricated to planar cross-stratified with yellowish-red to reddish-brown
(5YR 4-5/6 to 5-7/4) matrix. Basal contacts commonly scoured. 60-140 m thick.
Tertiary Santa Fe Group Units (pre-Palomas Formation)
Younger alluvial fan deposits graded to Qay2—Deposit is as described for Qay,
with stronger surface clast varnish and soil development (up to stage II carbonate
morphology). More eroded and featuring almost no bar-and-swale topographic
relief. Locally features a pinkish white (7.5YR 8/3) matrix east of the Rio Grande.
Qfayh
Qf2
QTpwlt
Younger alluvial fan deposits graded to Qay1—Deposit is as described for Qay,
with weaker surface clast varnish and soil development. Perhaps less eroded and
featuring greater (up to 20 cm) of bar-and-swale topographic relief than Qfay2.
Younger and modern alluvial fan deposits, undivided—Younger alluvium
(Qfay) and subordinate modern alluvium (Qfam) deposited on alluvial fans.
Qf1
QTpwl
Younger alluvial fan deposits—Pebbly sand to sandy gravel in very thin- to
medium-, tabular to lenticular beds, unconsolidated to weakly
carbonate-cemented, clast-supported, and massive to planar cross-stratified
with brown to light-brown (7.5-10YR 4-6/3-4) matrix. Buried soils are marked by
stage I to II carbonate morphologies. Commonly capped by thin A horizons. Up
to approximately 4 m thick. Locally subdivided.
Qfaym
Qary
Qfay
Qfah
QTpa
Sediment transport direction determined from crossbeds




Qf1
Qfah
QTpe
tg
Qfah
Qfe
Qtr
Qf1
Qtge
QTpa
Qfary
Quaternary Terrace Deposits
Qtr4
Qf1
Qam
o






1
1000
1 MILE
5.3–0.78
Ma


o

Qes
o
Qamh


o


1000
0
Mid-Pleistocene


am
h
am
Q
r4



 





o

ry
fa
h
mh
Qa
w
Qtg
ay
Q

Q
Tp
a
r
Qay
m

Qtp2








QTpa


Qf
ao
o




ry
Qa
Q
a
Qt
p2
ym
Qa
pwt
QT
QTpwu
Qa
yr

Qa
Qf2


Qam


Qf2
tp
2
Q
Qayr
Q
o
pwu
Qtp
Qtp2
QT
2
Qtp
4?

Qtp2



Qf
2
Qf3
Qt



o
0.5
A
Younger and recent (historical + modern) alluvium, undivided—Younger
alluvium (Qay) and subordinate recent alluvium (Qah + Qam).
Qtr1
Qtge
QTpa
Qah
Q
Qahm


Qt
p1




















o


o




QTpwu






287000
Qf1




Qfe
Qary
Qfe
o
 
 

o







 






o









o

tr4
Qah
107°17'30"W
1
Elephant
Butte

286000
1:24,000
Roads...........................................................................©2006-2010 Tele Atlas
Names.............................................................................................GNIS, 2008
Hydrography............................................National Hydrography Dataset, 2005
Contours........................................................National Elevation Dataset, 2000
Cuchillo
285000
107°20'0"W
Base map from U.S. Geological Survey 2010.
North American Datum of 1983 (NAD83) World Geodetic System of 1984 (WGS84).
Projection and 1000-meter grid: Universal Transverse Mercator, Zone 13S
10 000-foot ticks: New Mexico Coordinate System of 1983(west zone), shown in blue.
Williamsburg
NW
QTpwu QTpwuc
Qaym
Q
Qfahm
Qfay
284000





283000
Qtr4
Qam
QTpwm
QTpwu
QTpa
Qfe
3656 000

107°22'30"W
QTpwu
282000

281000
QTpwu

280000
m
Qaym
Qfay
279000
Qah
Qamh
Qtr1a
Qtr4
QTpwm
Qtge
QTpe
Qamh
Qfe
Qtr4

Qtgw
gw
QTpwu
Qfahy
2
Qamh
Qah
Qfamh
QTpa Qfaym
QTpwu
Qfahm
sc
c
wu
Tp
Q
Qt
Qfamh
QTpwm
QTpwm
Qtgw
Qtr4
Qfay
Qfahm
r
Qtr4
Qamh
Qah Qahm
Qtge
QTpa
Qah Qtge
Qah Qfe
Qfahm
QTpa
Qay

33°0'0"N
QTpwuc
Qahy
4
Qahm
Qtge
Qfah
3
QTpwm
Qahm
Qtg Qf1
e
Qay
Qah
Qtr5
Qahm

QTpwu
Qesc
Qamy
QTpa 5
Qtr4
Qe

Qamh
o
Qtgw
o


Qahm

QTpwu

QTpwu
Qfahm
Recent (historical + modern) alluvial fan deposits—Historical (Qfah) and
modern (Qfam) fan alluvium in approximately equal proportions.
Qfao
QTpwmc
QTpa
QTpe
3
QTpa
QTpwm
Qah
Qes/Qah
Qahm
sc
3
Sediment transport direction determined from imbrication

ah
Qayr
Fluvial transport direction
5
QTpe
QTpe
QTpa
pe
QT
pa
QT
QTpe
Qah
Qe
Qamh
QTpwm


Qaym
Qary



Qamy
QTpwu
Qfay
Qfayr
Qfay


Qtgw
3654000

 
Qaym
Qtge
s
Qe
Qfahm
Qahm
Qfahm
Qtr4

Qtr4
Qah
Qfah Q
Tp
e
QTpa
Qamh
Qtr5
Qtro
3657 000
Younger and historical alluvium, undivided—Younger alluvium (Qay) and
subordinate historical alluvium (Qah).
Inclined metamorphic or tectonic foliation—Showing strike and dip
5
Qf
QTpa
QTpe
Qfe Qes
Qamh
QTpwm




Qfay


3

Qtro



Qayr
QTpwu Qay
QTpwuc
daf
Qfamh
QTpwm
Qtro
Qamh
Qayh
Vertical flow banding, lamination, layering, or foliation in igneous rock—Showing strike






Qayr
Qary



QTpa
QTper
Qfahm
QTpa
Qfary Qfahm


Qfay
Qfay
Qary

QTpa
Qes
Qfam
Qtr1b
Qfahm
Qfay
Qfah

Qar
Qam
Qtr1a
Qfay
Qtgw
Qayh QTpwmc QTpwm
5
Qfah
Qfamh
Qfayr
Inclined flow banding, lamination, layering, or foliation in igneous rock—Showing strike
and dip
5
QTpef
Qfamh
Qfah Qes/Qfah
Qamh
Qfam Qes/Qfahm
Qah
Qfay
Gently inclined bedding, as determined remotely or from aerial photographs—Showing
approximate strike and direction of dip
5
QTpef
Qamh
Qay
Qfah
Qfahm
Qfahm
Qtr5

Qay
Qfary
Qfay
QTpwu
Qahm
Qfar
Qfayr
QTpwm
Historical and modern alluvial fan deposits, undivided—Historical alluvium
(Qfah) and subordinate modern alluvium (Qfam) deposited on alluvial fans
Historical and younger alluvial fan deposits, undivided—Historical alluvium
(Qfah) and subordinate younger alluvium (Qfay) deposited on alluvial fans.
Qfay2
QTpwt
Historical alluvial fan deposits—Pebbly sand to sandy pebble-cobble-boulder
gravel in medium- to thick-, tabular beds, unconsolidated, clast- to
matrix-supported, and massive to imbricated with very pale-brown (10YR 7/3)
matrix. May preserve weak soils with stage I carbonate morphology.
Non-varnished surface retains bar-and-swale relief of up to 20 cm. 1.2–2 m thick.
Qfahy
Qfay1
Younger alluvium, younger allostratigraphic unit—Pebbly sand, sandy gravel,
and sand in very thin- to medium-, lenticular to tabular beds looser than Qay2
deposits and lacks buried soils, gravels are commonly imbricated, locally silty
(1–15% silt), with a grayish-brown to pale-brown (10YR 5/2-6/3) matrix. Soil is
marked by weak accumulation of calcium carbonate (stage I carbonate
morphology). Up to 4.5 m thick.
Younger and modern alluvium, undivided—Younger alluvium (Qay) and
subordinate modern alluvium (Qam).
QTpwu
Modern alluvial fan deposits— Pebbly sand to sandy, pebble-cobble gravel in
channels and low-lying bars, unconsolidated, matrix-supported, and massive
with sand that is light-yellowish-brown to pale-brown (10YR 6/4 to 7/2-3) and
locally ripple laminated. Maximum thickness approximately 2.5 m.
Modern and younger alluvial fan deposits, undivided—Modern alluvium
(Qfam) and subordinate younger alluvium (Qfay) deposited on alluvial fans.
Qfahm
Younger alluvium—Sand and pebbly sand to sandy-pebble-cobble gravel in
very thin- to thick-, tabular beds, weakly to moderately consolidated and
massive to horizontal-planar laminated or imbricated, sand is mostly brown to
light-brown (7.5YR5/2-4; 6/3-4; 10YR 5/3). Cumulic soil development is common
in fine-grained beds. Calcic horizons (stage I to II carbonate morphology)
locally common. Typically 2–5 m thick.
Qaym
QTpwuc
Terrace deposits of ephemeral drainages west of the Rio Grande—Sand and
gravel in medium- to thick-, tabular to lenticular beds, gravel is imbricated and
sand lenses may be planar- or trough-cross-stratified with reddish-brown (5YR
4/4) to light-brown (7.5YR 6/3) matrix. Exhibits stage I-II carbonate morphology
and is capped by A and/or cambic horizons up to 50 cm thick. Forms strath
terrace deposits that underlie surfaces 6–20 m above modern grade. 1–2 m thick.
Qfamy
Historical and younger alluvium, undivided—Historical alluvium (Qah) and
subordinate younger alluvium (Qay).
Younger alluvium, older allostratigraphic unit—Deposit is as described for
Qay, but top soil exhibits stage II carbonate morphology and slightly reddened
soil. Sediment is slightly more consolidated than Qay1 unit. 2–5 m thick.
QTpef
Terrace deposits of ephemeral drainages east of the Rio Grande—Sandy,
pebble-cobble gravel in medium- to thick-, tabular to lenticular beds,
unconsolidated, commonly imbricated, and occasionally planar-cross-stratified,
with light-grayish-brown (10YR 6/2) matrix. Tread height 17–19 m above grade.
Typically a thin (1–3 m) thick strath terrace deposit.
Modern and historical alluvial fan deposits, undivided—Modern alluvium
(Qfam) and subordinate historical alluvium (Qfah) deposited on alluvial fans.
Historical and modern alluvium, undivided—Historical alluvium (Qah) and
subordinate modern alluvium (Qam).
Qay2
Inclined bedding—Showing strike and dip
3658 000
QTper
Qamh
Qfah
Qaarg
Qayr
5
QTpef
o
QTpwu
Qam
QTper
Qfahm
QTper
Qfah
Qfah
QTpwm
Qaym
Qay
QTpwmc
Qay
QTpac


Qfay
3655000
Qfay
Qary

Qfay
Qahm
Qamh
Qfah
Qtr4
Qay
o
QTpef
Qfay
Horizontal bedding

33°2'30"N

Qah
Qamh
Qfay
QTpwmc
QTpa
Qes/Qah
Qfay
QTpwm
QTper

Qfay
QTpwmc
2
Qam
Qayr
Qfayh

QTpa
QTpwm
Qaym
QTpac
QTpwu
Qfay
Qay QTpwmc
Qay
Qay
Qfay
QTpwm
Qam
Qfay
QTpwmc
Qay
QTpac
Qfah
Q
Qfayr
far
y Qayr
a
 
 
Q
Qay

Qfay

Qam

Qfay

QTpac
QTpwm
Qfay
QTpwu
QTpwm
QTpwu
Qam
Qfay

QTpwu
Qfay
Qfay
Qaym
p
QT
Qar
 
Qfay


o




Qary
Qfay
Qay
Qayr Qayh
y
o
2
Qary
Qfaym
QTpwu
o 

Qfay
QTpwu
Qa

Qay
QTpa
QTper
Qes
Qes
Qah
Qes/Qtr5
A’
Qfahm
Qes
y
fa
Q

daf
Qay
Qfar?
Qaym
QTpwm
Qay
Qay
Qfay
2
o
Qary
Qayr
QTpwuc
Qay
QTpwmc
Qtgw
18
Qes
Qah
Qfayr
QTpwm
QTpa
 
Qamy
o
Qtgw 5
2 Qamy
QTpwm
Qamy
Qaym
o
Qam
Qes

Normal Fault—Identity and existence certain; solid where exposed, dashed where
intermittent, dotted where concealed. Queried where identity is questionable. Bar-and-ball
on downthrown block.
Key Bed—Carbonate marker-bed in QTpwt
QTpef
5
Qay1
Gradational Contact—Identity and existence certain; solid where exposed and dashed
where approximate
Oblique-slip Fault, right-lateral offset—Identity and existence certain, location accurate.
Arrows show relative motion.
3659 000
Qah
Qam
3
QTpa
Qfay Qes
Qfahm
Qam
Qah

wm
QTpwm
QTper
QTpa
Qesc/QTpef
Qfahm
Qay
Qtgw
QTpwu
QTpwm
Qay
Qaym
QTpwt
Qfay
QTpef
Qfahm


Qes
o
Qamy
Qtr3



Qary
Qayh QTpwu
Qfah QTpwu
2
Qay
3656000
QTpwm
o

Qayr
Qay
Qay
Qfay Qayr
ym
QTpwu
h
Qa
3
Qfamh
QTpa
Qtr1a


75
QTpa
Qfamh
Qfah
 
Geologic Contact—Identity and existence certain; solid where exposed, dashed where
intermittent, and queried where identity is questionable.
Fault—Identity or existence certain, location approximate.

o
Qfayr


Qahm
Qfay
Qfahm
Qay
y
Qa

QTper
Fourth or upper terrace deposit of Palomas Creek—Sandy, pebble-cobble
gravel, with brown (7.5YR 4-5/3) matrix. Varnish on up to 80% of clasts at
surface. Soil development uncommon (likely eroded). Moderately dissected in
places. Tread height 40–47 m above modern grade. 5–8 m thick.
Qfamh
Qfah
Historical alluvium—Pebbly sand and sandy-pebble gravel in very thin- to
thick-, tabular to lenticular beds, loosely consolidated and massive to
horizontal-planar laminated or imbricated, brown (7.5YR 6/4) to grayish or
yellowish-brown (10YR 5/4) matrix. Surface features subdued bar-and-swale
topography with less than 0.4 m of relief. Tread is 0.4–1.3 m above modern
grade. Possibly up to 3 m thick.
Qary
Explanation of Map Symbols
Qfe
3660 000
Qah
Qfam
Modern alluvium—Unconsolidated, sandy, pebble-cobble gravel underlying
channels and forming transverse to longitudinal bars with up to 0.6 m of local
relief, brown to light-brownish-gray (7.5-10YR 6/3-6/2). Clasts east of the Rio
Grande include granite and Paleozoic carbonates. To the west, clasts are
dominated by volcanic lithologies derived from the Sierra Cuchillo and Black
Range. Thickness likely 1–3 m.
Recent (historical + modern) and younger alluvium, undivided—Recent
alluvium (Qah + Qam) and subordinate younger alluvium (Qay).
Third or middle terrace deposit of Palomas Creek—Very weakly calcareous
and thin- to thick-bedded, imbricated to weakly planar-cross-stratified with
fine- to medium-graind pebbles, concentrated along bases of individual foresets,
with brown (10YR 5/3) matrix. Varnish on up to 50% of clasts at surface.
Contains more feldspar grains (up to 70%) than other terrace deposits. Tread
height 33–40 m above modern grade. 1.4–3 m thick.
Quaternary Alluvial Fan Units
Active alluvium of the Rio Grande—Sandy, pebble-cobble gravel in the axial
channel of the Rio Grande, commonly in longitudinal or transverse bars.
Boulders may be present, transported from local tributaries to the active
channel during significant flood events. Clast lithologies are diverse, reflecting
bedrock exposed throughout Rio Grande catchment. Total thickness unknown
but likely 1–5 m.
Recent (historical + modern) and younger alluvium, undivided—Historical
alluvium (Qah) and modern alluvium (Qam) in approximately equal proportions.
Qay


Disturbed or artificial fill—Sand and gravel that has been moved by humans
to form berms and dams, or has been reworked/remobilized for construction of
infrastructure or buildings.
Qar
QTpe
2
Qah
Qtgw
Qfay
3661 000

QTpwu



Qay
Qfah
Qa
4


Qary

Qtr5
Qfah
Qahy
QTpe
5
Qahm
Qahm
2
Qah
Qay
Qamy



Qaym
Qay
Qaym
QTpwu
QTpwuc
QTpwu




Qayr
Qahm
 QTpwm
QTpwm
Qay


QTpwu
QTpa
Qtge
Qamh
Qay
Qay
o
Qfah
QTpwm
QTpwm





QTpa
Qes/Qfah
Qay
QTpwt






Qary
Qesc



1
Qah
Qah
Qay
QTpwm

Qfahm
QTpwm
QTpwm
Qay1
Qary




Qay
Qahm
Qay
QTpwm
Qaym
Qes
Qahm
daf
76
Qfe
Qtge
Qah
QTpwm
QTpa
Qfahm
3662 000
Qtge
QTpa
QTpa
Qfah
m
Qamy
Qam
Qtr4
61
Qtge
QTpa
Qamh
Qaym



Qaym
Qayr
QTpwt
h
Qa
ah
o
2
Q
Qayr
5
Qesc
Qtr4
86
QTper
4
m
Qah
Qfamh

QTpa
QTp
w
QTpwu
wu
Tp
Qay
wm

QTpwm

3
9 Qay1
Qfahm
Qtgw
pa
QTpwu
Qay
Qam
QT
Qfay1
Q
3658000
Qay1
Qfah
Qtr1a
QTpa
Qa
Qfam
Qahm
Qfe
Qah
Qfahm

Qtgw
Qtgw

o
Qfayr
Qay2
daf
Qtgw
3
QTpwm
=m
Qahm
Qtge
Qfe
Qtge
Qfahm
Qahm
Qtgw
o
Qfary
QTpwm
Qtgw
o
Qtgw
8
mh
Qfamh
QTpa
Qfah

Qtgw
Qtgw
QTpwm
Qa Qtgw
yr
Qtgw
Qah
Qtr4
Qfahm

ayr Qes/Qay
QTpwt
QTpwm


r
Qtgw
Qtgw



Qay
Qtgw
6

Qtgw
QTpwt
QTpwm
s/Q
Qah
Qtgw


Qah
QTpwu
QTpwu
Qay1
Qahm
daf
Qahm
Qay
QTpwm
Tp
o
Qamy
Qfah
Qe
=g
59
QTpe
Qsc
Qfah
Qfamh
Qfah
b
Qtr5
Qah
Qfah
QTpwt
QTpwt
2
Qa
Qfe
2
Qfam
Qam
Qtp1b
QTpwm
Qfahm
QTpwu
Qay2
3657000
Qfahm
Qtp1
Qahm
daf
QTpwu
Qay2
QTpwt
QTpwm
5
4
QTpwuc
wm
5
QTpwu
Qary
Qay2
Qtgw

Qtgw
Qfah
Qtgw
Tp
Qah
Qtgw
Qahm
3
Qay
33°2'30"N
Q
Qay
Q
o
3659000
Qay2
Qfahm
o
QTpwu
Qfah
daf
Qfayr
Qahm
QTpwu

Qtgw
Qfar
7
o
Qfayr
Qay2
Qahm
Qtgw
Qf1
QTpa QTpa
Qfe
QTpe
Qfahm
Qah
Qahm
Qtgw
Qah
Qtgw
Qayr
QTpa

Qf1
Qahy
Qfah
QTpwt
QTpwm
QTpe
QTpe
o
Qfahm Qfah
Qf1
Qamh
m
Qfayh
Qfay?
Qay
Qay2
Qahm
=u
Qtge
Slopewash and colluvium, undivided—Pebbly to silty sand found on bedrock
highs, unconsolidated to very weakly carbonate cemented, and massive to
thick-bedded, light-yellowish-brown (10YR 6/4). Commonly bioturbated by fine
roots. 1.5–2.5 m thick. Locally mapped as mantling older units (Qsc/unit).
Modern and younger alluvium, undivided—Modern alluvium (Qam) and
subordinate younger alluvium (Qay).
Qah
Qtp4
Eolian sand, slopewash, and hillslope colluvium, undivided—Mixed
windblown sand, pebbly sand, and pebble-cobble-boulder gravel found on lee
sides of ridges east of the Rio Grande. Unconsolidated and massive to rippled
where dominated by sand. Gravel are poorly sorted and angular to subangular.
Commonly vegetated with sparse soil development. Maximum thickness likely
no more than 3 m. Locally mapped as mantling older units(Qesc/unit).
Qamy
Oma
Oml
Oepb
Oep
Oeps
Eolian sand—Well-sorted sand found atop and on lee sides of ridges east of the
Rio Grande. Pale-brown to light-yellowish-brown (10YR 6/3-4). Forms
pod-shaped coppice dunes. Occasionally features a cambic horizon or stage I
carbonate morphology in upper part. Derived from Rio Grande floodplain
anddeflated Palomas Formation deposits. Maximum thickness 2.5 m. Locally
mapped as mantling older units (Qes/unit).
Modern and historical alluvium, undivided—Modern alluvium (Qam) and
subordinate historical alluvium (Qah).
3
Qamh 
Qtr4
Qa
y
Qfayh
QTpwm
Qayh
Qah
Qtp1b
QTpa
ah
Qfayr
Qtgw
Om
Qtp3
Qamh
QTpe
Qfe
Qay
Qfay
QTpwm
Tsus
w
8
Qfe
yh
Qahy
Proterozoic
Qahm
Qa
Qtp2
Fee #1
up
Ts
Qah
Qam
Qfah
QTpwm
Qay
Qfam
QTpwm

Qayr
Qahm
Qfayh
yh
Iorio
QTpwt
Qahm
fa
Barney
QTpwt
QTpa
Qam
Qah
Qtr1a
Qf
Qfay
Qf1
Qtgw
QTpwm
Qfe
Qay
Qfayh
Qayr
Qayr
Qtp2
QTpef
Tsubf

Tsus
Qes
Qtp1b
Qam
Qfe
Qes
o
ry
Qah
T
Q
2
QTpwm QTpwm





Qa
Qtgw
QTpwt
Qtgw

Qtgw
Qtgw
m
pw


Qay
Qfary
Qf1 Qf1
yr Qfah
fa
Q
QTpwu
Qf1
Qary
QTpwt
Qfary
Qtgw
Qtgw
Qf1
Qtgw

hm
Qfayr
Qah


Qary
Qayr


Cambrian
33°5'0"N
=u
61
Q
Qah
QTpwm












Qay
Qay
Qar
Qay
Qtgw
Qfay
Qayh
Qa
Qfay





Qtgw
y
ar
Qtgw
w
Qahm
Qay
Qah
Qay
Qtg
5
Qfayr
Qfayr
QTpwt
o
Q
Qah
Qf1
2
Qfahm
Qah
3660000
o
Qfahm
4
Qayr
Qay
yr
Qay
o
Qfah
QTpwu








daf
31
71
Qfe
Qtr1a
Qayr
Qaarg
o
r
Qfamh
Qtgw
Qfahm
Qay
Qa
y
Qfa
Qfary
1
Qahm
Qsc
Qes
QTpa
m
Qamh
Qam
Qtr1b
Qfay
Qa
Qahy
Qamh
QTpwm
Qtp3
Qtp2
daf
Qtr1b
Qfahy
Qfay
Qfay
QTpa QTpa
o
Qfahy
QTpwuc
QTpwt
Qar
Qay
3
QTpwm
QTpwu
Qtgw
Qam
y

Qayh
tp
Qf3
Qamh
QTpwt
Qay
Qfay
Qfahy
Qfary
QTpwt

y
fa
Q
QTpwm
Qtp3
Qtp2

Qam
_Ob
45
Qsc
m
Qfa
Q

Qayr
QTpwu
QTpwm Qf2
Qfar
Qayr
Qar
Qamh
daf
_Ob
Oepb

Oeps
QTpe
3663 000
40
Oeps
Qes
QTpa
Qaarg
ah
Qf
QTpwt
Qay
QTpwu
Qfay
Qayr
Qar
QTpwuc
h
o

6
Qay
Qahm
Qfary
Oepb

Qes
Qfe
Qah
Qa

Qay
QTpwt
Qar
Qfaym
Qay
Qayr
Qf3
Qes
Qayr
Qfah

Qary
Qayr
Qam

Qam
QTpwuc
Qayr
QTpwm
Qes
Qes
Qahm
Qtr3
Qtp3
Qtp3
Qfahm
QTpa
QTpwt
QTpwu
Qa
y2
Qam
daf
QTpwt
Qay
Qay
Qahy
QTpwt
Qayr
QTpwt
QTpwt

Qfahy

yr
Qf3
Qfe
Qfe
Ordovician
36
QTpe
Qes
Qfe
Qam


Qay
Qa
QTpwm
Qf3
Qtp2
Qf4
2

QTpwm
Qf4
tp
2
Qtr1b
Qesc
Qahm
QTpa
Qam
Qf4
Q
Qfayh
QTpe QTper
Qary


Qay
Qtp2
Qfao
3662000
QTpwt
Qary
Qar Qtp1a
Qary
Qayr
Qamh
Qf2
Qam
QTpac

Qay
QTpwt
Qf2
Qah
Qfam
Qtr4
Oligocene
Oma
Oml
Qes

1
QTpwu
Qtr3
Qes/Qtr4
Qes/Qtr4
Qes
Qfayh
ay
Qf
QTpwt
Qf2
Qah
o
o
Qay
QTpwt
Qtp2
Qtp2
QTpwm
Qtr2
3664 000
Qes/Qah
Qes


QTpwu
Qf2
QTpa

QTpwu
QTpwt
3661000
Qf2

Qay
Qay
Qahm
Qf2
Qtp2
Qtp1a
1
QTpwt

QTpwu
Qfay
Qf3
u
Qayr
10

Qay
QT
Qfay
Qam
Qamh
QTpwm
Qfay
QTpwm
 
Qay
QTpwt
pw
Qam
Qfay
Qfe
Qes
QTpe
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Palomas Formation—Sand, silt, gravel, and clay deposited by coalesced fan
complexes and the ancestral Rio Grande. Where not significantly eroded, the
surface soil is marked by a 1–2 m thick petrocalcic horizon (stage IV carbonate
morphology). Type sections of the Palomas Formation are found at
NW1/4NW1/4 sec. 30 and NE1/4SW1/4 sec. 33, T. 14 S., R. 4 W. Total thickness
240–275 m. Subdivided into 12 units:
Oeps
Axial facies of the Palomas Formation—Pebbly to silty sand and subordinate
pebble-cobble gravel in laminated to very thick-, tabular to lenticular beds,
horizontal-planar laminated to planar or trough-cross-stratified, with a sand
and gravel matrix that are light-brown (7.5YR 6/4) to pale-brown (10YR 6/3) or
light- gray (10YR 7/2). 40–115 m thick in a ~1.5 km belt on either side of the Rio
Grande. Divided into 2 subfacies:
Alema Member of the Montoya Formation—Dark-gray to dark-brownish-gray,
thin- to medium-bedded, massive to occasionally laminated, non- to sparsely
fossiliferous dolostone with subordinate wackestone, packstone, and jasperoid.
Packstone contains lacy networks of dark-brown chert. The brachiopods
Rafinesquina and Zygospira are found in the lower half (Mason, 1976). Forms
dark-colored slopes with isolated outcrops. 53 m thick.
Lower Member of the Montoya Formation—Brownish-gray, cherty dolostone
overlying white to medium-gray, quartzose sandstone with a dolomitic matrix.
Dolostone occurs in thick- to very thick-, tabular beds and is massive to laminated
with vertical burrows. Subangular to subrounded, pebbly conglomerate
interfingers with basal dolostone. Fine- to medium-grained sandstone occurs in
reverse-graded beds. Total thickness 37 m.
Bat Cave Member of the El Pasa Formation—Medium- to pinkish-gray, thin- to
thick-bedded, massive to ripple-laminated, cherty wackestone to grainstone.
Fossils include brachiopods, crinoids, trilobites, and stromatolites. The latter occur
as thin-algal mats or domal structures. Chert occurs as wavy laminae, vertical
veinlets, or pebble-sized nodules to extensive lenses. Ledge-former. Total thickness
approximately 65 m.
Sierrite Limestone—Medium- to dark-brownish-gray, thin- to medium-bedded,
tabular, massive, sparsely fossiliferous, dolomitic packstone. Chert occurs in wavy
bands, veinlets, or lenses and nodules, and weathers black or dark-brown. Contains
vertical burrows filled with dolomite. Gradational basal contact features thin layers
of interbedded siltstone and limestone or jasperoid. Total thickness 53 m.
Cambrian
_Ob
Coarse-grained axial facies of the Palomas Formation—Sandy, pebble-cobble
gravel/conglomerate in medium- to very thick-, tabular to lenticular beds,
weakly to strongly consolidated, moderately calcareous, and massive to well
imbricated to planar cross-stratified with light yellowish brown to very pale
brown (10YR 6/4-7/3) matrix. Common manganese coats on clasts. Basal scour
contacts on finer-grained sediment feature up to 3 m of topographic relief.
Bliss Formation—Very dark-brown to nearly-black, well indurated, thin- to
medium-bedded, rarely wavy-bedded, tabular, massive to broadly cross stratified
sandstone. Well-sorted, sub-angular to sub-rounded, quartzose, and very fine- to
fine-grained with subordinate, non-calcareous siltstone. Common peloidal
glauconite. Generally forms slopes beneath ledges of Oeps. Total thickness 12 m.
Proterozoic Bedrock Units
=u
Fine-grained axial faces of the Palomas formation—Pebbly sand/sandstone
and mudstone in thick laminations to thick beds, unconsolidated, non- to
weakly calcareous, and massive to trough- or planar-cross-stratified with
pale-brown to light-gray (10YR 6/3 to 7/2) matrix. Mud-rip-up clasts at the base of
beds and ellipsoidal concretions are common. Unit features up to 30% medium
to thick beds of yellowish red (5YR 5/8) to olive (5Y 5/3), fossiliferous mudstone.
=g
Eastern piedmont facies of the Palomas Formation—Sandy, granule-pebble,
pebble-cobble, and pebble-cobble-boulder gravel in thin- to very thick-, tabular
to lenticular to wedge-shaped beds, subordinate facies include silty sand and
silty clay in thinly laminated to very thick-, tabular to lenticular beds, with
redder hues (5-7.5YR) near mountain-front settings; browner hues (7.5-10YR) in
more distal facies. Maximum thickness 110 m.
=m
Plutonic and metamorphic rocks, undivided—Granitic gneiss, quartzofeldspathic schist, amphibolite, meta-siltstone, and granite in unknown
proportions. See individual descriptions for Proterozoic granite and metamorphic
rocks. Total thickness unknown.
Granite—Pink to pinkish-gray to red, hypidiomorphic granular, phaneritic, fineto very coarse-grained, locally gneissic granite. Phenocrysts include plagioclase,
microcline, quartz, and biotite. Groundmass is composed of feldspar, quartz, and
minor chlorite. Pink granite is poorly to moderately foliated; gneissic granite is
well-foliated. Total thickness unknown.
Metamorphic rocks—Unit mapped where metamorphic rocks constitute over 60%
of exposure. Dark-gray gneiss and dark- to tannish-gray quartzo-feldspathic schist
are strongly foliated. Subordinate amphibolite pods (roof pendants) and
reddish-brown meta-siltstone. Total thickness unknown.
CONTOUR INTERVAL 20 FEET
Saladone
Tank
Skute
Stone
Arroyo
Williamsburg
Caballo
NATIONAL GEODETIC VERTICAL DATUM OF 1988
Palomas
Gap
NEW MEXICO
Magnetic Declination
June, 2014
8º59' East
At Map Center
Apache
Gap
Mapping of this quadrangle was funded by a matching-funds grant from the STATEMAP program of the
National Cooperative Geologic Mapping Act (Fund No.G14AS00006), administered by the U. S.
Geological Survey, and by the New Mexico Bureau of Geology and Mineral Resources, (L. Greer Price,
Director and State Geologist, Dr. J. Michael Timmons, Assoc. Director for Mapping Programs).
Quadrangle Location
New Mexico Bureau of Geology and Mineral Resources
New Mexico Tech
801 Leroy Place
Socorro, New Mexico
87801-4796
Geologic Map of the
Williamsburg 7.5-Minute Quadrangle,
Sierra County, New Mexico
[575] 835-5490
A
A’
West
East
6,000
Bend in
Section
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4,000
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No. 1
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HS-146
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HS-316
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WS-737 HS-729
HS-773 HS-663
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Cross sections are constructed based upon the interpretations of the author made from geologic
mapping, and available geophysical, and subsurface (drillhole) data. Cross-sections should be used as
an aid to understanding the general geologic framework of the map area, and not be the sole source
of information for use in locating or designing wells, buildings, roads, or other man-made structures.
Geologic Cross Section
J
J
J J
http://geoinfo.nmt.edu
A geologic map displays information on the distribution, nature, orientation, and age relationships
of rock and deposits and the occurrence of structural features. Geologic and fault contacts are
irregular surfaces that form boundaries between different types or ages of units. Data depicted
on this geologic quadrangle map may be based on any of the following: reconnaissance field
geologic mapping, compilation of published and unpublished work, and photogeologic interpretation.
Locations of contacts are not surveyed, but are plotted by interpretation of the position of a given
contact onto a topographic base map; therefore, the accuracy of contact locations depends on the
scale of mapping and the interpretation of the geologist(s). Any enlargement of this map could cause
misunderstanding in the detail of mapping and may result in erroneous interpretations. Site-specific
conditions should be verified by detailed surface mapping or subsurface exploration. Topographic
and cultural changes associated with recent development may not be shown.
J
June, 2014
Comments to Map Users
J
This and other STATEMAP quadrangles are available
for free download in both PDF and ArcGIS formats at:
New Mexico Bureau of Geology and Mineral Resources
Open-file Geologic Map 250
QTpa
QTpa
QTper
QTpef
QTpwlt
QTpwl
QTpwlt
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1000
Tsu
New Mexico Bureau of Geology and Mineral Resources, 801 Leroy Place, Socorro, NM 87801
1
The map has not been reviewed according to New Mexico Bureau of Geology and Mineral Resources
standards. The contents of the report and map should not be considered final and complete until
reviewed and published by the New Mexico Bureau of Geology and Mineral Resources. The views and
conclusions contained in this document are those of the authors and should not be interpreted as
necessarily representing the official policies, either expressed or implied, of the State of New Mexico, or
the U.S. Government.
J
by
Andrew P. Jochems1 and Daniel J. Koning1
2,000
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500
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0 m asl