rapidly subsiding, allowing considerable
thicknessesof strata to accumulateduring the
Pennsylvanian.Abundant fauna preservedin
the Rowe-Mora Basin indicates ages from
Morrowan (Lower Pennsylvanian)to Upper
Des Moinesian (middle Upper Pennsylvanian). As depositioncontinuedinto late Pennsylvanian, the shoreline gradually moved
eastward toward the center of the basin;
howeverdepositionof continentalstratacontinued without cessationfrom Upper Pennsylvanianthrough Permian. Severalhundreds
to thousands of feet of fluvial sands, silts,
shales,and gravels with some isolated lacustrine and lagoonal limestone deposits were
depositedthroughout most of the Permian.
Near the end of the Permian, deposition
ceasedand erosionof the continentaldeposits
began. This hiatus extended through latest
Permianand lowermostTriassic.
The first Mesozoicdeposits(Upper Triassic)
consistof sandstones,
interbeddedlimestone
pebbleconglomerates,
and red-brownshales;
much of the material is derived from the
underlying Pennsylvanianand Permian strata
(Clark 1966).Intermittenterosionand deposition are reflected by disconformities that
separateUpper Permian from Triassic, and
Triassicfrom Jurassicrocks. Upper Jurassic
bedsare, in turn, separatedfrom the Dakotq
Formation (Lower Cretaceous) by disconformity indicating a brief period of nondepositionand erosionprior to the Cretaceous
marinetransgression.
Cyclesof marinetransgressions
and regressionsaccumulateda considerable
thicknessof
black shalewith some limestonebedsin the
Raton Basin,north and eastof the map area.
Toward the end of the Late Cretaceous,
local
uplifts, possibleforerunnersof the Laramide
Orogeny,expandedthe areasof the transgressive and regressivecycles,resultingin interbeddedblack shalesand gray to buff channel
sandstones.
Finally, the seawithdrewentirely,
depositingthe Trinidad Sandstoneas the last
regressive
unit.
The Laramide folding and upwarping that
marked the end of Cretaceoustime strongly
compressedthe basin into a seriesof westdippingthrustsand folds. As the orogenysubsidedduring the Eocene,erosionaccumulated
coarseclasticsin parts of the southernCieneguilla Creekdrainagebasin.Sometimeduring
the Oligocenea greatperiodof volcanismand
intrusion began,extendingthrough the Mioceneand into the Pliocene.Numerousstocks
and batholiths were intruded and basalt,
rhyolite, and andesite flows as well as tuffaceousmaterials were erupted to the north,
east,and southwestof the mappedarea. Normal and transverse flaulting concurrently
formed the Rio Grandedepressionto the west
and displaced the earlier thrust and reverse
faulting in the CieneguillaCreek drainage
basin. Locally, Precambrianrocks were exposed by the faulting, their erosion contributingto the thicknesses
of alluvialfill.
Late in Pliocenetime, basaltflows formed
the resistantpeaksof Agua Fria Mountain as
well as extensivecover over adjacent areas;
Ocate Mesa and numerous smaller lobes are
D. G., 1976,Summary of Precambriangeology
and geochronologyof northeasternNew Mexico:
New Mexico GeologicalSociety,Guidebook 27th
field conference,p. 129-135
Clark, K. F., 1966,Geologyand ore depositsof the
Eagle Nest quadrangle, New Mexico: Ph.D.
thesis,Universityof New Mexico,363p.
Goodknight,C. S., 1976,Cenozoicstructuralgeology of the Central Cimarron Range,New Mexico:
New Mexico GeologicalSociety,Guidebook27th
p. 137-140
field conference,
Kudo, A. M., 1976,A reviewof the volcanichistory
and stratigraphy of northeastern New Mexico:
New Mexico GeologicalSociety,Guidebook 27th
field conference,p. 109-ll0
Miller, J. P., Montgomery,A., and Sutherland,P.
K., 1963,Geologyof part of the southernSangre
de Cristo Mountains, New Mexico: New Mexico
Bureau of Mines and Mineral Resources,Mem.
l l , 1 0 6p .
Ray, L. L., and Smith,J. F., Jr., 1941,Geologyof
the Moreno Valley, New Mexico: Ceological
Societyof AmericaBull., v. 52,p. 171-210
Robinson,G. D., Wanek,A. A., Hays,W. H., and
McCallum,M. E., 1964,Philmont Country-the
rocks and landscapeof a famous New Mexico
ranch: U.S. GeologicalSurvey, Prof. Paper 505,
References
152p.
Armstrong,
A. K., 1955,Preliminary
observationsSmith, J. F., Jr., and Ray, L. L., 1943,Geologyof
on the Mississippian
Systemof northernNew
the Cimarron Range, New Mexico: Geological
Mexico:NewMexicoBureauof MinesandMinSocietyof America, Bull., 54, p. 891-9U
eralResources,
Circ.39,42p.
Thompson, M. L., 1942, Pennsylvaniansystemin
Baltz,E. H., and Read,C. B., 1960,Rocksof
New Mexico: New Mexico Bureauof Mines and
Mississippian
and probableDevonianage in
Bull. 17,92p.
MineralResources,
Sangrede Cristo Mountains, New Mexico: Wanek,A. A., and Read,C. 8., 1956,Taosto Eagle
AmericanAssociationof PetroleumGeologists, Nest and Elizabethtown:New Meilco Geological
Bull.,v. 4,p. 1749-1774
Society,Guidebook7th field conference,p. 82-93
remnantsof this former flow sheet.During
this time, the CieneguillaCreekdrainagewas
part of the south-flowing Coyote Creek
system.
During the Pleistocene,headwarderosion
of Cimarron Creek disrupted the upper
Coyote Creek drainage pattern. Cimarron
Creek captured the flow of upper Coyote
Creek, diverting it northward to form the
presentbasin. Three periodsof stability during the loweringof baselevel for Cieneguilla
Creekcreatedterracelevelswhich can still be
identified in the CieneguillaCreekdrainage.
Clark (1966) reported Pleistoceneglacial
deposition north of the mapped area around
WheelerPeak. Glaciationmay have contributedto the sedimentation
historyof the northern half of the Moreno Valley (Clark, 1966).
Evidenceof glacial activity is not discernible
in the basin.The presentbasinis the resultof
continued adjustment to the base level of
CieneguillaCreekand the drainagesystemof
theCimarronRiver.
Callender,
J. F., Robertson,
J. M., andBrookins,
Anoccurrence
ofredberyl
NewMexico
intheBlackRange,
b y F r a n k S . K l m b l e r a n d P a t r i c k E . H a y n e s , P . 0 . B o x 2 4 3 9 , C a m p8u7s8S0t a1t i o n , S o c o
A locality for red beryl in rhyolite was
found on May 23, 1979by P. E. Hayneswhile
prospectingfor the Virgin Mining Company.
The locality, on the west side of the Black
Range in the Gila National Forest of northwesternSierraCounty, New Mexico, has been
namedthe BerylliumVirgin prospect.
Generalgeologyand strucfure
The rocks in the region, mid-Tertiary or
younger, are comprisedof rhyolite, basalt
flows, and clasticsediments.Of primary interest are extensiveoutcrops of flow-layered,
purple-brown to pink, porphyritic rhyolite.
Phenocrysts are abundant, accounting for
about 40 percentof the rock. Oneto threepercentof the rhyolite consistsof vesicleswhich,
in part, are lined with severaloxide and silicate minerals, including beryl (Fries and
others, 1942;Lufkin, 1972).
The porphyriticrhyolite is cut by numerous
north-trending fissures;rocks adjacent to the
fissures are highly fractured. These fissures
and fracture zonesprovided a channelfor escapingvaporsduring the cooling of the lava.
These gaseousemanationswere responsible
for muchof the mineralizationin thearea.
The Beryllium Virgin prospect,in sec. 22,
T. l0 S., R. I I W., SierraCounty, New Mexico, has at least two distinct north-trending
fracture zones. Both are mineralizedand run
parallel to one another; each has its own distinct mineral assemblage.
Mlneralogy
Red beryl occursin the fracture zone on the
eastside of the mining claim. A more highly
mineralizedzone, devoid of beryl, lies on the
western side of the claim. Adjacent to this
zo\e are veins of massivehematite that contain crystalline grains of bixbyite and cassiterite. The following descriptionscover the
characteristicsand associations of the different minerals of interest found at the
Beryllium Virgin prospect.
Bnnyl-Be,Al:(SicO,s)-The
red beryl
from the Black Range of New Mexico is the
third known source for red beryl found in
rhyolite. Specimensfrom two other localities,
the Thomas Rangeand the Wah Wah Mountains in Utah, have larger, more colorful, and
more abundant crystals. Microprobe analysis
of the Utah crystals(Nassauand Wood, 1968)
.G
NewMexico Geologlt
February l9E0
15
occurs as Nassau,K., and Wood, D. L., 1968,An examinaHevertre-FezOr-Hematite
tion of red beryl from Utah: AmericanMineralplates(specularite)
throughoutthe
bright,
thin
indicatethat the red coloration is due to a high
ogist,v.53, p. 801
to
(Mn*2). The col- deposit.The largestcrystalsoccuradajcent
Northrop, S. A., 1959,Mineralsof New Mexico:
concentrationof manganese
the bixbyite in the mineralizedwesternfracAlbuquerque,New Mexico, Universityof New
or of the Black Range crystals grades from ture zone as vein fillings composedof interMexicoPress,665p.
pale pink to raspberryred, with the darker collockingplatesand bladeswith a maximumsize Palache,C. , 1934,Mineralsfrom TopazMountain,
The
or occurring only in a few crystals.
of about I cm.
tr
Utah: AmericanMineralogist,v. 19,p. 14
raspberry-redcrystalsare zonedparallel to the
quartz crystals
Qunnrz-SiO,-Colorless
of
the
in
the
center
C axis, with the red color
occur abundantlythroughoutthe deposit,in
crystal.
nearlyeveryvug. Maximum sizefor a crystal
The crystalsobservedoccur only in simple
is about 3 mm; doubly terminatedcrystals
tabular prisms. Under magnification, they havebeenfound.
show numerous fractures.Modifications or
ornr- (variety hyalite)-SiOr'nHzO, amortwins have not been noted among the fifty
NewMexico's
minerals
phous-Hyalite opal rarely occurs with the
The
are
crystals
specimenscollectedto date.
but more commonly with the red
bixbyite
weakly attachedto the rhyolite matrix due to
or thin
beryl. Foundas small,irregularmasses
the small amount of quartz sandoccurringin
palelavenderthat fadeson exposure
crusts
of
the vugs.Sizeof the beryl crystalsrangesfrom
to sunlight(Fries,1942).
I to 3 mm. Crystalsmuch larger than 3 mm
probablydo not occurat the BerylliumVirgin
prospect.Other depositsof red beryl may ocPresentcollectingstatus
cur in the Black Rangeof Sierraand Catron
red beryl crystalswith hammer
Collecting
Counties, but have not been discoveredto and chiselusuallyyieldsonly onespecimenper
date.The mineralsoccurringin the lithophysal working hour due to their scarcityand poor
cavitieswith the red beryl are quartz,hematite
the matrix. The areawherered
(variety specularite),and pseudobrookite;all attachmentto
is underclaim;collectingis prois
found
beryl
may penetratethe berylcrystals.
Gypsurr,r.CaSO..2H'O. LADRoN MouNratNs,
hibited until explorationof the claim by the
Btxrvrre-(Mn,Fe),O,-Bixbyite occursas
SoconnoCouNrv,N ew Mnxtco
is completed.
Virgin
Mining
Company
dull to very lustroussubmetalliccubesin the
Crystalsystem:monoclinic.Hardness:2
fracture zone on the west side of the claim,
Specific gravity: 2.32; Cleavage:.{ 0 I 0 }, perfect;
The cubesare rarely modifiedby the trisocta{ 100}distinct;{01I } distinct.
Selectedreferences
Gypsumis a commonmineralfound in sedih e d r o n{ 2 2 1 } , t h e o c t a h e d r o {nl l l } , o r , a s Fries,Carl, 1940,Tin depositsof the Black Range,
mentary rocks, cave deposits,and associated
observedin one specimen,the trapezohedron
Catron and SierraCounties,New Mexico: U.S.
with metallic ore deposits.This particular speCeologicalSurvey,Bull. 922-M,p.355
{2ll}. The usualsizeof the bixbyitecubesis
cimenis from a cavenearthe LadronMountains.
pseudocolan
edge;
two
specimens
lessthan 2 mm on
Fries,Carl, and others,1942,Bixbyiteand
Gypsum'sprimary use is in the manufactureof
brookitefrom thetin-bearingrhyoliteof theBlack
lectedin 1978measured8 mm on an edge.
plasterof paris.
Photo by Mark R. Leo
Range,New Mexico: AmericanMineralogist,v.
P s r u o o s n o o K I T E - F e ,T i O , - P s e u d o p.
21
305
,
brookite,whenfound with red beryl, occursas
thin, needle-likecrystalslessthan 2 mm long Lufkin, J. L., 1972, Tin mineralizationwithin
rhyolite flow-domes,Black Range,New Mexico:
and like the beryl, are lightly attachedto the
Ph.D. thesis,Stanford University,New Mexico
crystalsassothyolite matrix. Pseudobrookite
OpenBureauof Mines and Mineral Resources,
ciatedwith the bixbyiteattaina lengthof up to
file Rept.57,149p.
5 mm and a width of 1.5 mm, while single
1976,Oxide mineralsin microliterhyolite,
pseudobrookitecrystalsmay be found peneBlack Range, New Mexico: American Mineralogist,v.61, no. 5-6,p.425-430
tratingthe bixbyitecubes.
(continued
from previouspage)
lon Prolt 0rgaualo.
USPOSTAGI
PAID
NEW
MEXICO
SOCORRO,
NO9
PERMIT