Early
Paleocene
vertebrates,
and
stratigraphy
WestForkof Gallegos
biostratigraphy,
Ganyon,
NewMexico
SanJuanBasin,
by Spencer
G. Lucas,
Department
of Geology,
Albuquerque,
NM87131
University
of NewMexico,
Introduction
U.S. Bureauof Land Managementcollected
There are only three well known areasin in this area (Kues and others, 1977).
This paper reports the fossil vertebrates
the San |uan Basin where early Paleocene
(Puercan)vertebratesoccurin the lowermost collectedbv this field partv. establishestheir
strata of the Nacimiento Formation. These stratigraphicprovenance,ind discussestheir
areas,BetonnieTsosieWash,Kimbeto Wash, biostratigraphicsignificance.AMNH refers
and the headlandsof De-na-zin and Alamo to specimensin the Department of VerteWashes(Fig. 1), were already known when brate Paleontology,American Museum of
Sinclairand Granger(1914)published the re- Natural Historv; UNM refers to snecimens
sults of two field seasons (1912-1913) of in the Departmentof Geology,University of
stratigraphicand paleontologicstudiesof the New Mexico.
Paleoceneof the San Juan Basin. However,
Stratigraphy
Sinclairand Granger (1974,p.315) did mention a fourth occurrenceof Puercan verteMore than 37 m (l2I ft) of the Nacimiento
bratesin the headlandsof the West Fork of Formation are exposedin rugged badlands
GallegosCanyon (Fig. 1). The only verte- at the head of the WestFork of GallegosCanbratesthey reported from this locality (their yon (Figs.2, 3, 4).TheOjoAlamo Sandstone,
localitv4) were two teethof the Puercanmul- which underlies the Nacimiento Formation
titubeiculate " Polymastodon"
(: Taeniolabis). throughout the San Juan Basin (Baltz, 1,967),
No additional vertebrateswere collectedfrom is not exposedhere (Fig.2). Instead,the base
the West Fork of GallegosCanyon unlil1977 of the Nacimiento Formation is covered by
when a field party under contract with the Quaternaryalluvium that consistsmainly of
mudstoneand sandstonedetritus locally derived from the Nacimiento Formation (Qal,
and Qal, of Wells, 1982,fig. 101).However,
the Oio Alamo Sandstonedoes form the resistanibedrockunder the plateauincisedby
GallegosCanyon and its tributaries, and it
is exposed approximately 1 km (0.5 mi)
northwest of the head of the West Fork (Reeside, 1924,p. 30, pl. 1). This relationship to
the Ojo Alamo Sandstoneand the occurrence
of Puercan mammals indicate that the Nacimientostrataexposedhere are of the lower
oart
of the formation.
The exposedNacimiento Formation consists of mudstone (63%), sandstone(33Vo),
silcrete(3Vo),and siltstone(1%).Thesestrata
can be consideredin three parts (Fig. 4):
LowER MUDSTONES AND srLCRETns-The
lower 16.5m (54 ft) of sectionD (Fig. 3) and
correlatedunits of sectionsA-C (Fig. 3) consist of variegatedbands of red, green, buff,
and gray mudstone intercalatedwith thin,
resistantsilcretes.Some of these strata, especiallythe silcretes,are laterallycontinuous
for more than 1 km (0.6 mi) and thus allow
a securecorrelationof sectionsB-D (Fig. 3).
The silcretesare gray (but weather to yellowbrown), well-cemented,fine-grained,silicarich layers (Rains,1981).
MEDTAL
sANDSToNE
courlnx-A
thick (up
to 14m; 46 ft) and complexsequenceof sandstone and clayey sandstoneforms a prominent part of the Nacimiento Formation
exposedhere (Fig. 3). Most of the sandstone
is gray-white, trough crossbedded, fine
grained, and quartzose.However, two thin
but distinctivehorizons of black,fine- to medium-grainedsandstoneare present,one near
the base and the other near the top of the
sequence(Figs. 3, 5). Sinclair and Granger
Q91a, p. 305) attributed the black color of
this type of sandstone to the presenceof
manganeseoxide, but it seems likely that
iron oxide also contributesto the black color
and high density.Whether the formation of
these black sandstones was a syndepositional or diageneticevent is unclear,and their
genesisneeds further study.
The baseof the entire sandstonecomplex
is an erosionalsurfaceof low relief (Fig. 3).
At or near this base,fossil logs up to L m in
diameterare common (Fig. 6), and other fossil logs and wood fragments occur sporadicallythroughout the sandstonecomplex.All
fossil vertebrate occurrencesin the Nacimiento Formation at the head of the West
Fork are in the sandstonecomplex and are
with the blacksandstonehorizons
associated
(Fig.3). In fact,many of the vertebratefossils
FIGURE 1-Location map of study area, San Juan County, northwest New Mexico. The colored circles collectedare encasedwithin the black sandstone (Fig. 7D).
indicatelocationsof Pueicancollectingareasin the NacimientoFormation.
August 1984 Nao MexicoGeology
UPPER MUDSTONES/
SANDSTONES/
SILCRETES,
ANDsrLTSroNps-Inthis area, the upper part
of the Nacimiento Formation consisti of
deeply weatheredgray, green, buff, and black
mudstone and lesseramounts of sandstone,
silcrete,and siltstone (Fig. 3). A thick, brown,
medium-grained,and subarkosicsandstone
is presentat the top of the exposuresin the
northeastpart of the headlands(Fig. 3, section A).
A prominent erosionalunconformity separates Quaternary (and late Tertiary?) d^epositsfrom the underlying Nacimiento
Formation. These deposits are stable pediment and terracedeposits capped by eolian
sands (QTP1,;of Wells, 1982, frg. 1.0t).
Vertebratepaleontology
Twenty-one localities in the Nacimiento
Formation at the head of the West Fork of
GallegosCanyon (Fig. 2) have produced vertebratefossilsrepresentingthe fish, reptile,
and mammal taxa discussedbelow.
ClassOsrrrcHrHyESHuxlev, 1880
Family LEprsosrsrperCuviea 1825
Genus and speciesindeterminate
FIGURE2-Geologic map of the headlandsof the west Fork of GallegosCanyon,
SanJuan Counry, New Mexrco.
An incompletegar scale(UNM B-400c)and
two gar scales(UNM 8-388) were collected
from localities358 and 349, respectively.
ClassRrpulra Linnaeus, 1758
Order TEsruorlps Linnaeus, 1758
Genus Asprotnnns Hay, 7904
Aspideretes
sp.
Quoternory
deposils
upper mudslones,
soodsiones,
si cretes ond
silistones
/
]
Lo*", verlebrotes
Mediol sondstone
c o m p le x
Fossim
l ommcls
o n d o w e rv e r t e b r o t e s
( / o c o l i t i e3s4 \ 3 4 5 ,
3 4 8 ,3 4 9 , 3 5 O , 3 5 t ,
354, 357,358,36O,
UNM 8-385, a nearly complete but fragmented carapace(locality347)is assignedio
Aspideretes
becauseit has eight pairs of costals and the ridge-and-pit ornamentation
characteristicof this genus. Six speciesof
Aspideretes
are recognizedfrom the Puercan
of the Sanfuan Basin(Gilmore, 1979,pp.5662; Matthew, 1937,p. 332),and the genus is
in need of revision. Becauseof this, no species-leveldeterminationof UNM 8-385 is'attempted. UNM 8-1082 (locality 1037)consists
of shell fragmentsidentical to thoseof UNM
8-385.
Genus and speciesindeterminate
Undiagnostic turtle-shell fragments and
other postcraniawere observedbut not collectedat localities345,346,347,348,349,352,
353,355,358,L037,1038,and 1039.
Order Eosucnra Broom, 1914
Genus Cueupsos.qunusCope, 7877
Champsosaurus
sp.
T-:-l
'
'
Unconsolidoied
Sond
F::=i
Mudstone
li-..,----Illsondrton"fllllllllll.',^.^,^
I
F:rJ
t!"".":,,"""
sittsrone
FIGURE3-correlation of measuredstratigraphicsectionsof the lower part
of the
NacimientoFormation in the headlandsof"thi west Fork or crii"g;, eu'nyon,
---'r-" sun
JuanCounty,New Mexico.SeeFig. 2 for locationof each,".tio.r.'--
UNM B-381a(locality344)is a small. amphiplatyan vertebralcentrum. This centrum
has a ventral keel, a circular cross section,
slightly concavesides, a large neurocentral
sutureon its superior surface,parapophyses
that are confluentwith the diapophyses,and
a slight dorso-ventral compression posteriorly. Clearly, this small (length : t4 mm)
centrum is an anterior dorsal centrum of
Champsosaurus,
but it is inadequatefor a species-levelidentification (Erickson, 1972).-G.
Nm MexicoGeology August'l9M
Order Cnocoorr-n Gmelin, 1788
Genus AuocNaruosucHus Mook, 1921
Allognathosuchus
mookiSimpson, 1930
(locality 349); 8-396, teeth (locality 353); B398a,partial skull (locality354);B-400a,partial lower jaw (locality358);and B-1086,teeth
(locality 1039).
UNM 8-1121 (locality 351) is a fragmentary lower jaw still bearing one globoseand
striatedtooth. The anterior part of this lower
iaw bearsthree alveoli followed bv a much
iarger alveolus,which, in turn, is'followed
by four much smalleralveoli. The diameters
of theseeight alveoli (5, 4.5, 4.4, 1.25,5.5,
5.5, 4.5, and 4.0 mm from front to back) are
somewhatgreaterthan thoseof AMNH 6780,
the holotype of A. mooki(Simpson, 1930,p.
7), but otherwisethe UNM andAMNH specimens are identical.Assignment of UNM B1121to A. mookithus seemscertain. Other
specimensfrom the West Fork of Gallegos
Canyonthat probablypertain to A. mookiare:
UNM 8-382, teeth (locality 344);8-387, teeth FIGURE6-Fossil los at baseof medial sandstone
complexnear locality 1102,lower part of the Nacimiento Formation in the headlands of the West
Fork of GallegosCanyon.
Genus Lnoyosucuus Lambe, t907
?Leidyosuchus
sp.
Storrs and others (1983)described UNM
B-401a (locality 360), the oldest known endocastofan eusuchiancrocodilian.Basedon
skull fragments of UNM V407a, they tentatively identified this specimen as LeidyoThe bicarinate,conicalteethand skull
suchus.
fragmentsof UNM 8-1083(locality1037)also
may pertain to Leidyosuchils.
If these identifications are correct, they represent the first
from the Puercan of
report of Leidyosuchus
the San fuan Basin.
Genus and speciesindeterminate
Undiagnostic crocodilian remains were
observedbut not collectedat localities344,
u5, 346, 349, 352, 353, 355, 356, 358, 359,
1037,t038, and 1039.UNM 8-394 0ocalitv
351)is an eusuchianvertebralcentrum, and
UNM 8-1085 (locality1038)is the distal portion of a crocodiliantibia.
FIGURE 4-Badlands of the lower part
'the of the Nacimiento Formation, headlands of
West Fork
of Gallegos Canyon, in S1/2,sec. 15, T. 25 N , R.
72W L,lower mudstones and silcretes; M, medial
sandstone complex; U, upper mudstones, sandstones, silcretes, and siltstones.
FIGURE S-Black sandstone in medial sandstone
complex at top of measured stratigraphic section
C (Figs. 2, 3), lower part of the Nacimiento Formation in the headlands of the West Fork of Gallegos Canyon Rock hammer is 28 cm long
58
August 1984 NetuMexicoGeology
FIGURE 7-Selected fossil mammals from the Nacimiento Formation in the headlands of the West Fork
taoensis,leftMl, occlusalview; B, UNM B-400b, Taeof CallegosCanyon. A, UNM V386, Taeniolabis
niolabistaoensis,left I'?(?),lateral view; C, UNM V389, Desmatoclaenus
sp, left M{?), occlusal view; D,
priscus,right
UNM B-401b,Desmatoclaenus
sp., right Pr-Mr, occlusalview; E, UNM 8-397, Loxolophus
dentary fragment with partial Mt and complete M2 ,, occlusalview; F, UNM 8-392, Loxolophus
hyattianus,
left dentary fragment with partial M1, completeMz, and nearly completeM:, occlusalview; G, UNM
V1,277, Loxolophuspentacus,left dentary fragment with Mt-r, occlusal view.
ClassMeruvALrALinnaeus, 1758
Order MUITTTUBERCULATA
Cope, 1884
Genus TarNrorears Cope,'1882
(Cope, 1882)
Taeniolabis
taoensis
TABLE l-Measurements
(in mm) of lower molars of selected specimens of Loxolophus. L : maximum
length, AW : maximum trigonid width, PW : maximum talonid width; * indicates an approximate
measurement of a worn or damaged tooth.
LAWPWLAWPW
Sinclairand Granger(191a,p.315) noted Specimen
that at the head of the West Fork of Gallegos L. priscus:
Canyon "only two specimens were fou--nd AMNH 3108 (holotype)
6.4
4.9
5.4
(both Polymastodon| : Taeniolabislteeth)."
UNM 8_393
6.5
5.1
However,only one AMNH specimen,1631,7, UNM 8_397
5.7
a right dentary bearing M, of T. taoensis,
is L. hyattinnus:
AMNH 16343
5.5
4.3
Iabelledas having come from the West Fork
3.7
UNM 8_392
4.6
of GallegosCanyon.Also, the recordof specimenscollectedby Sinclairand Grangeronly
lists AMNH 76317from "ab't. 5 mi. N.W of
Ojo Alamo Head of WestFork of Gallego[slc]
(Matthew, 7937,fig.2F., pl. 17, fig. 2). UNM
Wash" (Grangerand others, 7913,p.2q.
(locality 1039)is a large (length : 7.1
8-1087
Threespecimensof T. taoensis
in the UNM
collection were found in the West Fork of mm, width : 10.3mm), right M3that closely
GallegosCanyon. UNM 8-381 (locality 344) resemblesthe M3 of AMNH 954,a specimen
is the posterior third of a left M. nearly iden- that Matthew (1937,pl. 13, fig.3) referredto
tical in size and morphology to AMNH 3046 as L. pentacus.
(Grangerand Simpson,1929,fig.8A). UNM
Loxolophus
rr,::;(Cope, 1888)
8-386 (Fig. 7A), from locality 348,is a left M'
that is about the same size (length : 23.5
Loxolophus
hyattianus(Cope, 1885)
mm; width : 17.7 mm) as AMNH 16305
(Grangerand Simpson, 1929,p. 619).UNM
Without documentation,Van Valen (1978,
8-386 has 10 labial, nine medial, and 11 lin- p. 56) consideredL. priscusto be a synonym
gual cusps,as doesAMNH 970(Grangerand of L. hyattianus.However, my examination
Simpson, 1929, hg.88) and is between the of AMNH and UNM specimensreferableto
'tyoung" and "adult"
stagesof wear defined these taxa reveals coniistent differencesin
forTaeniolabis
by Grangerand Simpson(1929, size (Table 1) and morphology that justify
figs. 3A-B). Finally, UNM B-400b Fig. zB), Matthew's (1937,pp.43,53) conclusionthat
from locality 358,is a left tr(?)fragment with these speciesare distinct. The distinctions
two accessorycuspuleson its posterioredge. between L. priscusand L, hyattianusare reIt probably pertains to Taeniolabis,
although vealedwell by consideringthe threerelevant
it di+fjrsslightly from AMNH 16319(Granger specimens from the West Fork of Gallegos
and Simpson, 7929,fig.2A), which has only Canyon in the UNM collection. UNM 8-397
one accessorycuspuleon its posterior edge. (locality354)is a right dentary fragmentwith
partial M, and complete M.. (Fig. 7E) assigned here to L. priscus,as is UNIM 8-393
Order CoNoyLARTHRA
Cope, 18g1
(locality351),a right dentary fragmentbearGenus Pzrurrycuus Cope, 1881
Periptychus
t-18M, and part of M,. UNM 8-392 (locality
coarctatus
Cope, 1883
351), on the other hand, is a left dentarv
UNM B-398b(localiry354)is a maxillarv bearing partial M,,
complete M,, and nearly
fragmentbearing partial right Mr ,. It clearlv complete
M, (Fig. 7F) assigned here to L.
pertainsIo Periptychus,
and the following fea'- hyattianus.V397 and 8-393 are larger than
tures justify assignment to P. coarclatus: 8-392 (Table 1),
their molar cusps are lower
Mr2 are relativelywide linguolabiallv.their and more
massive,their molars are broader
hypoconesand piotostylesa"relingualio their (Table1), and,
on V397, the M. is longer and
protocones,and their conulesare very small broader ("less
reduced" ) than is the M, of
(seeMatthew, 1937,p. 123).
v392.
UNM 8-391 (locality350)is the lingual half
Genus Crursolcuus Rigby, 19g1
of a right M' that closelyresembles"thecorGillisonchus
gillianus(Cope, 1882)
respondingportion of the M'of AMNH 3121,
_ UNM B-1088a(locality 1039)is a right M,. the holotype of L. hyattianus,and AMNH
In size (length : 4.1 mm, rrigonid wiath :
1.6343,a specimen referred to L. hyattianus
3.2 mm, talonid width : 3.1 mm) and mor- by Matthew (1937,p. 44, fig.lB). UNM Bphology it is identical to the M, of UNM 399(locality35f is d right dentary fragment
8-029, a partial skeleton of G. gillianus de- with roots of M, .; its close resemblanceto
scribedby Rigby (1981).
UNM 8-397 supports provisional referral to
L. prtscus.
Genus LoxoropuusCope, 1885
Loxolophus
pentacus(Cope, 1888)
Genus DnsuerocresNus Gazin, 1941,
Desmatoclaenus
sp.
UNM 8-1271 (Fig. 7c), from locality 1102,
is a left dentary fragment bearing roois of po
UNM B-401b(locality360)is a right P.-M,
and heavily -oll M._.. Its size (M, length :
(Fig. 7D). This relatively small specimen(M,
9.1 mm, trigonid width : 7.3 mm, tilonid
length : 6.0 mm, trigonid width : 4.5 mm,
width : 8.2 mm) and morphology are verv talonid width : 4.9 mm) appears to be an
closeto those of AMNH 3i92 1M]'tengtn i
arctocyonid with unusually molariform pre9.3 mm, trigonid width : 7.5 mm, tilonid
molars.Thus, the presenceof low but strbng
width : 8.5 mm), the holotype of L. pentacus paraconids and metaconids and small tal-
LAWPW
7- 7
6.7
6.2
7.6
6.9
6.3
d.J
5./
4./
5.8
6.2
4.6
5.5
4.7
5.4
6.7
6.5*
3.8
4.3
3.6
^;-
onids on the Pr_oof UNM B-401b preclude
assignmentto Oxyclaenus
simplex,O. cuspidatus, and Loxolovhushaattianus-arctocvonids in its size range. The only arctocyonidI
have examined with Dremolars as molariform as those of UNM B-401b is Desmatoclaenushermaeus
from the Dragon local fauna
of Utah (Gazin, 1941,fig. 19), which is much
larger than UNM B-401b. It is possible that
the UNM specimenis a partial lower dentition of the smaller,Puercanspeciesof Desmatoclaenus,
D. dianae(Van Valen, 7978,p.
57). Nevertheless,until the lower dentition
of D. dianaeis adequatelydescribed,I only
refer UNM B-401b to Desmatoclaenus
sp.
UNM 8-389 (locality 349) is a left M'(?)
missing its labial edge (Fig. 7C). Like UNM
V401b, it appears to be an arctocyonid, but
it is difficult to identify becauseof its unusually large hypocone and completelingual cingulum. In sizeand morphology it most closely
resemblesspecimensof Desmatoclaenus
pro(compare with AMNH 3253;Cope,
togonioides
1884,pl. 25F, fig.17), although I have not
seen a specimen of D. protogonioidesthat
combines a complete lingual cingulum with
as large a hypocone as is present on UNM
B-401b. Thus, identification of the UNM
specimen as Desmatoclaenus
sp. seems reasonable.
Genus and speciesindeterminate
UNM 8-1084 (locality 1038)is a fragmentary but edentulousmaxillary about the size
of Periptychus.
UNM B-1088b(locality 1039)
is root and enamel fragments of a smaller
mammal, and UNM 8-384 consistsof postcrania fragments, including a partial tibia
comparablein size to the tibia of Periptychus.
Biostratigraphy
The occurrence of Taeniolabis
taoensis,Periptychuscoarctatus,
Gillisonchus
gillianus,Loxolophuspentacus,
L. priscus,and L. hyattianus
supports assignment of the mammal-producing interval of the Nacimiento Formation
in the headlandsof the WestFork of Gallegos
Canyon to the Puercanland-mammal "age"
(Wood and others, 1941; Russell, 1967).A
secondvertebrate-producinginterval is presentT-9 m (23-29 ft) above this interval (Fig.
3), but has only produced lower vertebratei.
Although assigningthis upper interval to the
Puercanmight be doubted, data (Lucasand
New Mexico Geology Atglst
1,984
Schoch, 1982)indicate that Torrejonian (including "Dragonian") horizons in the Nacimiento Formation are at least 50 m (164ft)
above Puercan horizons (Sinclair and Grange1 191,4;Lindsay and others, 1981;Tomida,
L981),so it is likely that the upper vertebrateproducing interval along the West Fork of
GallegosCanyon is Puercan.
Historicallv. the occurrenceof Taeniolabis
in
the mammallproducing interval would be accepted as evidence that this interval pertains
to the Taeniolabis,or upper, "zone" of the
Puercan.However, in the headlandsof the
West Fork of GallegosCanyon, there is no
mammal-producing interval to correspond
to the Ectocon
rrs,or lower, "zone" of the Puercan. In Kimbeto and BetonnieTsosieWashes
"zorre"
the reverseis the case:an Ectoconus
mammal-producing interval is not overlain
"zone" interval. Only in the
by a Taeniolabis
headlandsof De-na-zin and Alamo Washes
are mammal-producing intervals representing both "zones" present in a single stratigraPnlc sequence.
There are two alternate explanations for
the distribution of these Puerian "zones" in
the San Juan Basin:
1) The Taeniolabis
and Ectomnus"zones"
do represent successiveintervals of
Puercan time. The absence of fossil
mammalsrepresentingone or the other
zone in Kimbeto Wash, BetonnieTsosie Wash, and the West Fork of Gallegos Canyon reflects inadequate
sampling, biased preservation, or
stratigraphic differences in the lower
part of the Nacimiento Formation in
ihese areas.
2) These"zones"do not representsuccessivetime intervals. Instead, sampling biases or facies differences have
controlled the occurrence of certain
mammal taxa (notably Taeniolabis).
Sinclairand Granger (1974)and, most recently,Lindsay and others(1981)favored the
first explanation.Matthew (1937)and, most
recently,Van Valen (1978)favored the second
explanation.
However, I find it difficult to choose between the two alternatives. More detailed
taxonomic and phylogenetic studies of Puercan mammals/ more intensive collecting in
the lower part of the NacimientoFormation,
and more detailedstratigraphicstudy of these
rocks with the aim of arriving at a correlation
of Puercanstrata of the Nacimiento Formation independent of the fossil mammals seem
necessaryin order to determine fully the
validity of the Puercan"zones."
ACKNowLEDGMENTS-I thank M. C. McKenna and R. H. Tedford for permission to
study specimens in the AMNH. R. Schoch
aided in the identification of some specimens, and comments by M. Middleton and
D. Wolberg improved the content and clarity
of this paper. I am grateful also to W. Gavin,
R. Lah, T. Lehman, J. McClammer, and P.
Reser for assistance in the field.
August 1984 New MexicoGeology
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Colorado and New Mexico: U.S. Geological Survey,
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Rigby, J K., Jr.,1981.,A skeleton of Gillisonchusgillianus
(Mammalia; Condylarthra) from the early Paleocene
(Puercan)Ojo Alamo Sandstone,San Juan Basin, New
Mexico, with comments on the local stratigraphy of
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Advances in San Juan Basin paleontology: University
of New Mexico Press,Albuquerque, New Mexico, pp.
89-126.
Russell,D. E.,7957, Le Paleocene
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names
Geographic
onGeographic
Names
U.S.Board
Crystal Creek-stream, 32 km (20 mi) long, heads
in the Chuska Mountains in New Mexico near
WashingtonPassat 36"05'04'N., 708"51''22' W.,
flows west into Arizona to join Cattail Wash at
the head of Coyote Wash 12.9 km (8 mi) west
of Crystal, NM; Apache County, AZ, and San
W.;
Juan County, NM; 36'04'52"N., 109"08'56"
1959 description revised; nof: Coyote Wash,
SimpsonCreek (BGN 1915).
Maverick Spring-spring, in the PeloncilloMountains, 3.5 km (2.2mi) north of Mount Baldy and
9.9 km (6.1mi) west of Eakins;Hidalgo County,
New Mexico;31'43'10'N., 108"55'50'W.;not:
Mavarick Spring.
Spring Cteek-stream, 72.9km (8 mi) long, heads
at the iunction of Estufaand Las CuatasCreeks
on the south side of Stove Ridge in New Mexico
at 36'58'35"N., 106"44'20'W.,flows west-northwest to the Navajo River at Chromo, Colorado;
Archuleta County, Colorado, and Rio Arriba
County, New Mexico; sec.9, T. 32 N., R. 1 E.,
NMPM; 37'07'58'N., 106'50'45'W.; noi: Stove
Creek.
StoveCreek-stream, 5.6 km (3.5mi) long, heads
in Colorado on the north slope of Stove Ridge
at 36"59'35"N., L06'44'35' W., fl ows west-northwest through New Mexico to Spring Creek 5.6
km (3.5mi) southeastof Chromo, Colorado;ArchuletaCounty, Colorado,and RioArriba County,
New Mexico; 37'00'73' N., 706'47'20' W.
Tanbark Canyon-canyon, 3.2 km (2 mi) long,
headsat 3329'34' N ., 105"47'76"W., trends south
to Bonito Creek, 19 km (12 mi) northwest of
Ruidoso; Lincoln County, New Mexico; sec. 3,
T. 10S., R. 11E., NMPM;33'28'02"N., 705"47'06'
W.
Taylor Draw-ravine, 6.4 km (4 mi) long, heads
at the baseof theAnimas Mountainsat 31'31'15"
N., 108"48'40'W.,trends southwestthen northwest to join FosterDraw at the head of Animas
Creek0.48km (0.3mi) northeastof Gray Ranch;
Hidalgo County, New Mexico; sec.16, T.325.,
R. 20 W., NMPM; 37"30'28'N., 108"52'07'W.
Valle Largo-meadow, in the Sangre de Cristo
Mountains, 1.5 km (0.9 mi) northwest of Osha
Passand 20.9km (13mi) east-southeastof Taos;
TaosCounty, New Mexico; sec.3, T. 24 N., R.
15 E., NMPM; 36"20'54'N.,105'20'25'W.
White Place-locality, in PlayasValley 18.8km (11.7
mi) east of Animas; Hidalgo County, New Mexico; 31'58'15"N., 108'36'40"W.; not: Playas.
Wind Canyon-<anyon, 2.4 km (1.5mi) long, heads
in the SierraBlancaon north slope of the Double
Diamond Peaksat 33"34'09'N., 105'47'40"W,
trends northeast to open out 9.7 km (6 mi)
southeast of Carrizozo; Lincoln County, New
Mexico;sec.27,T.8 S.,R. 11E., NMPM; 3335'10'
W.
N., 105'47',00"
'J.2.9
km (8 mi) long,
Ysletafro Canyon---canyon,
headsin the SacramentoMountains at 33"03'52"
N., 105'51' W., trends northwest to Tularosa
Canyon 9.7 km (6 mi) northeastof Tularosa;reported to have been named for the mission and
Tiwa pueblo called Corpus Christi de la Isleta
(Ysleta)del Sur, on the Rio Grande southeastof
El Paso,Texas,becausetimber used for the mission was cut in this canyon about 1682;Otero
County, New Mexico; sec.72, T. 14 S., R. 10 E.,
NMPM; 33"06'47'N., 105"56'17'W.; not: Ranchario Canyon.
-DavidW. Love
NMBMMR
Correspondent