Sulfide/barite/fluoritemineraldeposits, Guadalupe Mountains, NewMexico and west byCarol A. Hrl/,Consulting Geologist, 17 ElArco Drive, Albuquerque, NM87123

Abstract along Basinand Rangefault zones(Wood, Rocky Arroyo prospect (Teepeemine, Sulfide/barite/fluorite mineral depos- 1958).The Bird and Bissettmines in the Pitts and Price,fr.) its in the Guada.lupeMountains are sim- Glass Mountains are associatedwith in- The Rocky Arroyo prospect (RA) is in ilar to those elsewhere in the Delaware trusive bodies (King, 1930).Despite var- SEt/c sec. 26 T2lS R24E along Walt Can- Basin: (1) they are all mineralogically iations in location (from Guadalupe yon -1 km (-0.6 mi) south of NM-137 simple (containing pyrite and usually Mountains to Fort Stockton;Fig. 1) and where the road crossesRockv Arroyo. This sphalerite, calcite, dolomite, and some- geologic association (igneous intrusions, prospect, unlike most of the other mineral times barite, fluorite, or galena);(2) most faults, structural and stratigraphic traps), depositsin the GuadalupeMountains, is have sulfur-isotope values ranging from the mineral deposits around the margins 6vS= - 9 to + (3) have not a sulfide deposit. It is a uranium de- 5%o;and most car- of the appear to be re- bon-orygen-isotope values ranging from posit where uranium (as much as 2.35Vo; 6t:g- - 5 lo - !5%o,61EO: - 3 to - 107oo. lated. Mineralogy in all of the deposits is Waltman, 1954;Mclemore, 1983)as well The deposits are in structural and strat- similar, and sulfur-isotope values of sul- as arsenic,barium, copper, molybdenum, igraphii traps, occupying the same po- fide minerals usually fall within a fairly nickel (Table 1) are concentrated in -9 and sition as many of the cavesin the narrow range of values(6sS: to I5%o, hydrocarbon (thucholite) pellets dissem- Guadalupe Mountains. The sulfide/bar- CDT) regardlessof location (Fig. 2). Car- inated in the dolomite of the PermianSeven ite/fluorite deposits around the Dela- bon-oxygen-isotope values of ganguecal- Rivers Formation (not in the Yates For- ware Basin are considered to be of the cite also usually plot within a discrete mation as statedby Finch, 1972).The dis- Mississippi Valley type (MVTs). isotopic field (ore-sparfield, PDB, Fig. 3). The origin of MW mineral deposits tribution of the pellets seems to be in the Guadalupe Mountains may be re- controlled by a small, inclined fracture zone lated to the degassing of the Delaware (Motts, 1962), alongwhich a 2 x 2 x 20 Basin where HrS moved from basin to Description of mineral deposits m (6.5 x 6.5 x 65 ft) adit has been ex- carbonate-reefmargin and accumulated Mines, prospects, and other mineral cavated in the dolomite. Hill (1989)re- there in structuraland shatigraphictraps. deposits ported a U-Pb ageof 350-449Ma for the Mineral deposition is believed to be Ol- in the Guadalupe Mountains will be described from the vicinity of Carls- hydrocarbon pellets and suggested that igocene-Miocene in age, a time when these pellets might possibly be derived these traps were still within the reduced bad, , southwestward to- zone. Later, in the Pliocene-Pleistocene, ward , Texas.In Fig. 1 from the uranium-rich Devonian Wood- as the mountains uplifted and regional mine localities are identified with letter ford shale in the subsurface. baselevel dropped, the trapped H2Sgas symbols. Mclemore (1983) reported two other was oxidized to sulfuric acid at or near uranium-petroleum sitesin the Rocky Ar- the water table, and the sulfuric acid dis- royo area: the W. H. ShafferRanch pits at solved out the large passages.Us- sec.27 T21S R24Eand a roadcut site at Golden Eagle mine (Lucky Strike, Lone ing the Delaware Basin as an example, NE1/+sec. 24 T2lS R24E. In the roadcut Eagle, or Ammon) I propose that the degassingof basinsis site anhydrite-nodulemolds are filled with a possible alternative model for the or- The Golden Eagle mine (GE) is in SW calcite;some also contain "dead oil." Ura- igin of other MVT deposits. 1/+sec. 74T2lS R25Eabout 13 km (8 mi) nium minerals in the "dead oil" have been northwest of Carlsbad,New Mexico.It is dated radiometrically as (Purvis recorded in the files of the Eddv Countv et al.,1988,p.97). Introduction Courthousethat H. H. Davidsonand Oh The sulfide/barite/fluorite deposits in the Davidson sold a claim on the property on Guadalupe Mountains, New Mexico and April 15, 7929, for $200 to the Carlsbad Little Walt prospect Texas, have been studied by King (L948), Copper Company, a partnershipconsist- Little Walt prospect (LW) is in SW'L sec. Mclemore (1983), Thompson (1983), and ing of foe Morosi and others,who named 2T2lS R24E.Motts (1962)speculated that North and Mclemore (1986, 1988). Most the claim the Lucky Strike no. 1. Soul6 the Little Walt was a copper mine like the of the mines and prospects in the Gua- (1956)used the names Lone Eagle and Golden Eagle, but in actuality very little dalupe Mountains probably were devel- Ammon for the mine, but the name Golden copper exists there (Table 1). Little Walt oped in the early 1900s(Thompson, 1983). Eagleappeared on Motts' (1962)map and "mine" is a prospect about 15 m (50 ft) or The mineral deposits are small (probably is the name that is used in this report. so in diameter and 2 m (6.5 ft) deep. A only a few tens of tons) and of low eco- Mclemore (1983,pp. 1-9L)described the 7.5-m-deep (24.6-ft-deep)shaft reported nomic potential. However, these mineral mine as an "open pit 6 m deep with a 7.5 by Mclemore (1983)was not observed at deposits are an important and integral part m decline (caved)." the site. The prospect is a slightly radio- of the geologic history of the Delaware The predominant mineralization at the active iron gossan (30 cps; Mclemore, Basin and may be crucial to understand- Golden Eagle mine is copper, but the de- 1983). Thin veins of resinous sphalerite ing the origin of all Mississippi Valley- posit also includes relatively high amounts were found in mineralized rock scattered type (MVT) deposits (Hill, 1993a,b). of lead and uranium (UrOr:0.004Vo, over the ground surface. Mineral deposits in the and Cu: 1,.05Vo,Mclemore, 1983;Pb :2590 The Little Walt prospect has the same Glass Mountains, although more exten- ppm, Table1). Greenmalachite is distrib- structural and stratigraphic position as the sive than those in the Guadalupe Moun- uted fairlv uniformlv as matrix material Golden Eaglemine: along a biohermal an- tains, have not been economicallv throughout the basafsiltstoneof the Yates ticline (part of the Waterhole anticlinor- profitable because of their small size, loi Formation. The mine is locatedalong an ium and Carlsbad fold complex) and at grade, and remoteness. The Seven Heart anticlinal (biohermal) feature trending ap- the baseof the YatesFormation. The Little Gap barite mine and the Buck zinc pros- proximatelyparallel to the reeffront (Motts, Walt anticline is the northern continua- pect in the Apache Mountains are located 7962\. tion of an anticlinal structure along which

August 1993 Nao MexicoGeology ( \ /'1 ( v

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''-^',,; ; ii"'i Fl. Slockton LEGEND SCALE 1 N a 2Okn. 'i,r, -/ol DISSOLUTION EDGE J4a r cENozorc FILL ,'1.'i..i'.j DEEPCENOZOTC r"-t f #.!"n, 39-37 Mo FIGURE l-Location map of sites mentioned in the text, table, and other figures. Counterclockwisefrom Carlsbad, New Mexico, around and then : within the Delaware Basin: GE Golden Eagle mine, RA = Rocky Arroyo prospect, LW : Little Walt prospect,-= MH : McKittrick Hill pyrite, MF = Middle Fork Waterhole marcasite, DC = Dark Canyon pyrite/marcasite,-2L : Two Ladies prospect, JG Jurnigan gossan, LC : Lechuguilla : : !gve, GR_: Guadalupe Ridge pyrite, 3F Three Fingers Cave Ridge pyrite, FC Fir Canyoh prospect, QG : Queen of the Guadalupes mine, CWC : Cottonwood Cave, LR : LonesomeRidge pyrite, L13 : Lucky 13 prospect, DDM = Devil's Den mine adit, DDP = Devil's Den prospects, CT : Calumet and Tejasmine, GH : Grisham Hunter prospect, GC : Glori Cave fluorite, BS = Bell Springs prospect, MC : McKittrick Cinyon : : : pyrite, CP _ Clve Peak fluorite, 7}{G Seven Heart Gap-: barite mine, BZ Buck zinc prospect, BD-: Bircl mine, BT Bissett mine, CCK : Comanche Creek, LN : Los Nietos, TG : TexasGulf, C Culberson sulfur mine, P : ?okorny sulfur deposit, LM = Leonard Minerals sulfur deposit, YH = Yeso Hills pyrite, BLS : Bell Lake sink. Basemap from Anderson (1981). 13

Nm Mexico Geology August 7993 all of the McKittrick Hill cavesare devel- 6 3as oped (Dry, Endless, McKittrick, Sand, and -30 -20 -to +lO +20 Little Sand; Hill, 1987). Pyrite collected MVT SULFIDES from the area of the McKittrick Hill GuadalupeMountains (backreef-reef) was analyzed by M. Buck (pers. comm. Ilrite, McKittrick Hill - 1989) for its sulfur-isotope content (MH, (M. Buck,p. c. 1989) Fig. 1; Fig. 2). Sphalerite,Jumigan gossan a Sphalerite,Little walt prospect a Pyrite,Guadalupe Ridge T Middle Fork Waterhole marcasite Pyrite,Three Fingers Cave Ridge a This site (MF) is in NE1/r sec. 16 T22S Pyrite,Lonesome Ridge a R25E about 1 km (0.6 mi) north of the Pyrite,Fir Canyonmine I Middle Fork Waterhole and 1 km (0.6 mi) Pyrite,Lucky 13prospect a south of Boyd's Canyon. The iron-sulfide Sphalerite,Grisham Hunter prospect o mineralization at this location has been Sphalerite,Devils Den prospect a identified as marcasite (P. Hlava, Sandia GuadalupeMtns. (basinmargin-forereef) Laboratories, pers. comm. 1993).The Sphalerite,Bell Springsprospect O marcasite is along or near the contact of Pyrite,McKittrick Canyon D the Yates and Tansill Formations and is ApacheMountains apparently confined to a single sequence Buck prospect a of thinly bedded dolomite (P. Sanchez, Sphalerite, zinc pers. comm. 1992). Despite its strata- (Kyle, 1990) bound occurrence,the marcasiteappears Sphalerite,Buck zincprospect o to be epigenetic, having been introduced GlassMountains into vugs and along mudcracks,fractures, Galena(minor sphalerite), Bird mine o and between bedding planes. In some Fort Stockton places the bladed marcasite crystals (up Sphalerite,galena, pyrite, Los Nietos a a o to a few centimeters long) appear to be (Mazzullo,1986) "smashed" on their upper surfaceswhere Basin growth was confined by an upper rock Pyrite,Yeso Hills O bed. The Middle Fork Waterhole marca- site is in a biohermal anticline located -5.5 NATIVE SULFUR km (-4 mi) west of the McGruder Hill Fort Stockton anticline (Motts, 1952). Sulfur.Texas Gulf o Basin Sulfur.castile buttes a D a I Dark Canyon pyritemarcasite (Kirklandand Evans, 1976) A good exposure of pyrite-marcasite can Sulfur,Culberson mine a be found in Dark Canyon (DC) in NE1/r Sulfur,Pokorny deposit a -0.6 sec.34 T23SR25E km (-0.4 mi) south (Davisand Kirkland, 1970) of Dark Canyonand 0.5km (0.3mi) north Sulfur,Leonard Minerals deposit of the Dark Canyon road. The pyrite forms cubes as much as 7.5 cm on a side, and FIGURE 2-Sulfur-isotope values, various types of ore deposits, Delaware Basin the marcasite forms spears as much as 5 cm long. The mineralization is found as vein or vug fillings in the Seven Rivers porous and spongy where mineralized. Formation near the baseof the Yates.The |urnigan gossan Dark Canyon pyrite-marcasite is located Owen (1983,p. 55) called the gossan a gossan (lG) is in SW1/asec. 8 along an anticlinal structure considered Jurnigan "mineralizeddike" of "sandstone,"but it T24S R26E just north of Draw by Motts (L962) to be of probable bio- furnigan is neither a dike nor sandstone. and 8 km (5 mi) north of White City at a hermal origin. point where the trend of the reef escarp- barite ment changes ftom a northeasterly to northerly direction (i.e., at the Cuevare- Exposedin the entrance sinkhole of Le- Two Ladies prospect entrant). chuguilla Cave (LC) is a small patch (-1 The gossan is about 8 m (26 ft) -10 The Two Ladies prospect (2L) is in NE in diameter, and there is a small prospect m2; ft'?)of tabular barite intergrown \l+SErltsec. 32 T23S R25E and was de- about 2 m (6.5ft) deepdug into the mass. with translucent, blocky calcite. The bar- scribed by North and Mclemore (1986,p. The gossan is located only a few kilo- ite crystals are as much as 1 cm long and 0.25 cm wide. Sulfur-isotopeanalysis of 4) as being a "replacement of carbonate meters from Doc Brito, Jurnigan#L,lur- and open-spacefilling in collapsebreccia nigan #2, and Wind (Hicks) Caves;all are the barite crystals shows a 6sS value of in dolomite of the Permian YatesForma- located less than 1.6 km (1 mi) from the + 40.6.The entrance to Lechuguilla Cave tion." According to R. North (pers. conun. reef edge and along the Reefanticline. is along a flexure superposed on the flank of the GuadalupeRidge 193) the prospect is associatedwith a deep Jumigan gossancontains relatively high southeastem natural sinkhole -30 anticline (|agnow, 1989).The barite is in and consists of m amounts of arsenic,copper, molybde- -8 (-100 ft) of workings in brecciated lime- num, lead, and zinc (Table1). Thin (0.5 the Seven Rivers Formation m (-26 stone/dolomite and a surface shaft -2 m cm) seamsof dark-brown, resinous sphal- ft) below its contact with the Yates For- (-6.5 ft) long. North found galena,smith- erite are present in the gossan, and silic- mation (D. fagnow, pers. comm. 1992). sonite, and hemimorphite at the Two La- ification of the masshas formed jasperoid. dies but no sphalerite. One assayedpiece Iron mineralization takes the form of box- Guadalupe Ridge pyrite of "dry-bone" rock was 27Voztnc (R. North, work and cement; the goethite/limonite Pyrite is concentratedat the baseof the pers. comm. 1993). permeatesthe Tansill Formation, which is YatesFormation all along the crest of the

August 1993 New MexicoGeology 6r3c and along the crestof the GuadalupeRidge anticline (jagnow, L977;Light et al., 1985). The mine is thought to have been devel- oped by a foe Weldy in l9M, although a note to this effect in the mineral claims office could not be verified by records in the Eddy County Courthouse.Early maps BEDROCK of the area called the gossan an "extinct volcanic crater" becausethe spongy, min- eralized rock looks like lava (R. Turner, 618o 618o pers. comm. L992). The Queen of the Guadalupes mine is developed in an iron-oxide gossan un- THERMALSPAR derlain by the Queen of the Guadalupes Cave, a natural, 70-m-deep(230-ft-deep), vertical shaft complex (mapped by Iag- now, 1977, and Thompson, 1983). The gossan contains relatively high amounts of barium, molybdenum, lead, and zinc (Table 1). Minerals identified by Thomp- son (1983) include barite, azurite, mala- chite, bornite, and hematite; however, R. North (pers. comm. 1993)and this study (Table1) found very little evidenceof cop- OIL SPAR per mineralization at this site. Sulfur-iso- tope analysesof the barite measured 6yS values of +58.0 and +62.t. Ganguecal- cite (part of the ore-spar field, Fig. 3) is present within the gossan, and the host rock has been both dolomitized and silic- ified.

Cottonwood Cave Cottonwood Cave (CWC) is located along the crest of the Guadalupe Ridge anticline 0.5 km (0.3mi) southeastof the BIOEPIGENETICSPAR Dark Canyon lookout tower in NE1/+sec. 6T265 R22E.The caveis developedin the Seven Rivers Formation, just beneath the YatesFormation; the basal bedding plane of the Yates defines the cave ceiling. The base of the YatesFormation above Cottonwood Cave is highly pyritic. Pyrite concretions collected directly above the cave show good epigenetic-replacement textures in thin section. Bedrock at the cave entrance (collected at the contact of -40 the Yates and Seven Rivers Formations) contains anomalously high amounts of 6lsc copper (5800ppm), lead (4210ppm), and FIGURE 3-Carbon--oxygen-isotope values, various calcite-sparepisodes, Delaware Basin. Sym- zinc (2700;Table 1). This site is important bols used are the same as those used in Fig. I caption. becauseit shows that the baseof the Yates is concentrated in metals even where a gossanis absent. Grladalupe Ridge anticline. Sampleswere ftJong) adit trending 245'. The prospect collectedat the GR locality alongthe ridge was briefly mentionedby Thompson(1.983, Lonesome Ridge by Light and Domenico (1983),at Three p. 4) as "exhibiting slight iron-oxide stain- On LonesomeRidge (LR), in NE1/asec. FingersCave parking lot (3F)by C. Mosch, ing." Two episodesof calcitemineraliza- 13 T265 R21E,another zone at the baseof and at other locations along Guadalupe tion are associatedwith the deposit: tiny the YatesFormation is abundant in pyrite Ridge by D. |agnow (Fig. 1). Sulfur-is-o- (1 mm or so), drusy calcite crystals lining (Light and Domenico, 1983;Light et al., tope analyseswere performedon someof cavities, overlain by larger (-0.5 cm), 1985).Pwite cubesas much as3.5 cm across these sampleswhere the pyrite had not milky, blocky calcite crystals partially or litter th-eground (Fig. 4), and pyrite fills completelyaltered to limonite (Fig. 2). totally filling thesecavities. joints trending N60'E, parallel to the reef front. The rock surrounding the pyritized Fir Canyon prospect Queen of the Guadalupesmine zone has been both dolomitized and si- licified. Fir Canyonprospect (FC) is in NE1Asec. The Queenof the Guadalupesmine (QG) 36 T25SR2lE approximately one-half the is in NE1/rsec. 1 T25SR21E -1.2 km (-0.7 way down from the top of Fir Canyonand mi) southwest of the Dark Canyon look- Lucky 13 prospect along the baseof a cliff in the SevenRivers out tower. The mine is locatedin the Seven The Lucky 13 prospect (L13) is in SE Formation. It consistsof a 2-m-long(5.5- Rivers Formation directly beneath the Yates 1/+s€c. LST263 R21Ejust north of Forest

Nm Mexico Geology August 1993 5t ServiceRoad 531.where the road makes and about 1.6km (1 mi) northeastof Lost (23 ft) in diameterand 2 m (5.5 ft) deep. a sharp bend before reaching a drill pad. Peak. The mine is located in the Seven It is located at the base of the YatesFor- A claim was filed on the prospect in the Rivers Formation, on a graben between mation about 30 m (100 ft) south of the Eddv Countv Courthouse bv Seth Mc- the Dog Canyon and Lost Peakfault zones. McKittrick Canyon trail just after the trail (4arch Coillum on 76.1940.' According to King Q9a8, p. 160): "The tops out on the Yatessiltstone ridge. It At the Lucky 13 minerals were depos- mine was worked from time to time since also trends approximately along the axis ited along a N5-10'W arcuate fault that about 1900but the workings are small and of the Reef anticline. The prospect was roughly parallels the main Dog Canyon were abandoned before our visit int934." dug into a highly silicified gossan.Drusy fault to the west. The prospect is located Recordsshow that in 1914 and 192627 quartz, quartz veins, botryoidal opal, and in the SevenRivers Formation -20 m (-65 approximately "66 tons of ore" containing yellow jaspercan be seenat the prospect. ft) below the baseof the Yates.The pros- "5256 lbs of copper" and "3 oz of silver" The gossan is also enriched in arsenic, pect is about 7 m (23 ft) deep and 1-2 m were mined from the Calumet and Tejas cadmium, lead, vanadium, and zinc (Ta- (3-6.5 ft) wide. Mineralogy consists of (Lasky and Wootton, 1933, p. 46). The ble 1). Some sphaleriteis present. mostly iron and zinc enhancement(Table Calumet and Tejasconsists of four sepa- 1); sphaleriteis presentas both vein and rate adits, 15-60 m (49-1,97ft) in length, Bell Springs prospect vug fillings. No calciteor quartz was noted driven into the Seven Rivers dolomite Bell Springsprospect (BS) is at latitude '1,04"48'52". at this site. (Thompson,1983). Epigenetic deposits of 31"55'37"and longitude It is copper and iron are found along thin joints the only prospect in the basin-margin fa- Devil's Den prospects(Broken and fault zoneswithin thesefour adits. cies, although much pyrite can be found Horseshoe claim) Mineral deposits reported at the Calu- in this stratigraphic position along bed- met and Telasmine include malachite, az- In sec.21 T265R21E, in the Devil's Den ding planes dipping up toward the reef urite, chrysocolla,beaverite, hematite, and Spring area,are three separateprospects (e.g., McKittrick Canyon, MC, Fig. 1). The possibly aurichalcite and bornite. Other and one short adit. In the SW1/+of this Bell Springs prospect is locatedat the con- metalenrichment besides copper includes section two prospects have been tact of the Lamar Member of the Bell Can- dug di- arsenic,bismuth, lead, vanadium, tung- rectly beneath the Yates Formation, yon Formation with the forereef facies of and sten, and zinc (Table 1). The deposits are another small (0.7 m deep and L m wide; the Capitan , where the Lamar in veins and along porous and fractured 2 ft deep and 3 ft wide) prospect (DDP) pinchesout on King's (1948)map, 1.6km zones in the Seven Rivers Formation; si- has been dug about 10 m (33ft) below the (1 mi) northeastof Bell Canyon. King (1948, licification and dolomitization of the min- base of the Yates along the road leading p. 160) and Price et al. (1983)gave ap- eralized rock are conspicuous. As in the to the remainsof the old Devil's Den Spring proximate locations for the prospec! dur- Devil's Den Spring area, pyrite/marcasite house. Slightly to the north and west ing this study the site was relocated. The of commonly are present along fine bedrock this road prospect, in the NW'A of sec. prospect is just inside of the wilderness fractures in the area of the Calumet and 21, is an adit (DDM) known as the Broken area,Guadalupe Mountains National Park, Tejasmine. -1840 Horseshoeclaim (Thompson, 1983;Fig. Texas,at an elevationof m (-6037 5). This adit is 14.6 (48 ft). m ft) long and Grisham Hunter prospect trends 150" before making a right-angle The Bell Springs prospect consistsof turn (maps by Thompson, 1983).The De- GrishamHunter prospect(GH) is at lat- two diggings: a S-m-deep,1-m-wide (16- vil's Den prospects lie close to the north- itude 31'58'14" and longitude 104"48'00" ft-deep, 3-ft-wide) shaft on the northeast trending series of Basin and Rangefaults in Guadalupe Mountains National Park, slope of a small ridge off of the main Radar along which Dog Canyon has been down- Texas.Price et al. (1983)gave an approx- Ridge and a l-m-deep, 3-m-wide (3-ft- dropped. imate location for the site and called it the deep, 10-ft-wide) prospect on the crest of Sphalerite found at the road prospect "unnamed prospect."The Grisham Hunter this small ridge. The deposit is predom- is reddish, reniform, and transparent to consistsof a shallow prospectabout 7 m inantly an iron gossan containing rela- submetallic. In contrast, the nearby Bro- ken Horseshoe claim area seems to be mineralized primarily with copper (Table 1). Glassyand drusy calcitecan be found at the adit as crystals lining vugs within sucrosic dolomite; milky, blocky calcite coatsthe glassy,drusy cilcite. Bdth types of calcite are intergrown with malachite and azurite. Specularhematite also has been reported from this locality (Thomp- son, 1983)but was not observed. The Devil's Den Spring area is also the site of considerablepyrite/marcasite min- eralization within highly fractured bed- rock (Fig. 6). This mineralization is important becausefracturing of the rock most likely took place during Basin and Range faulting, showing that the pyrltel marcasite were either contemporaneous with, or cameafter, at leastsome faulting.

Calumet and Teias mine (Calumet and Texas mine) The Calumet and Tejasmine (CT) is at latitude 3L'58'44' and longihrde 104'5055" in Guadalupe Mountains National Park, FIGURE 4-Pyrite cubes littering the surface of the Seven Rivers Formation near the base of the Texas,along the Upper Dog Canyon trail Yates Formation, Lonesome Ridge, Guadalupe Mountains. Photo by Carol Hill.

August 1993 New MexicoGeology cite is common at this site (ore-sparfield, Another report of fluorite along a roadcut Fig. 3). 3.4 km (2 mi) west of the lunction of US- 180 with TX-54 on the Salt Flats (A. Ken- Glori Cave fluorite dall, pers. comm. 1989)was also visited, Fluorite is exposedin Glori Cave (GC) but no fluorite could be found. on the north side of upper Shumard Can- yon along the western escarpmentof the Results Guadalupe Mountains, Guadalupe Mountains National Park (latitude 37"53'30",longitude 104'51'38").Glori Cave Field relationships is developed in the Victorio Peak Lime- Sulfide/barite/fluorite deposits in the stone of Leonardian age. Passagesfollow Guadalupe Mountains are located pri- northeast-and northwest-hendingjoints marily along structural (anticlines, faults) and truncate the fluorite mineralization and stratigraphic (base of Yates Forma- (i.e., cave-passagedissolution came after tion) traps. Of the 23 sites shown in the the fluorite). GuadalupeMountain sectionof Fig. I, t4 Fluorite in Glori Cave occurs as veins are located at the base of the Yates For- 1-8 cm wide that follow joints and frac- mation, five are within the Seven Rivers tures in the limestone, as crystal linings Formation (not directly at the base of the 0.5cm thick, and assmall crystals dissem- Yates), two are in the Tansill Formation inated in the limestone (Hill, 1988).The (one at the Yates-Tansillcontact), two are crystal cubesrange from a few millimeters where the basinal faciesinterfingers with to 2.5 cm on a side.Fluorite crystals come the forereef facies (BS and MC), and one in shades of brown and purple, but in is in the Victorio Peak Limestone (GC). general an earlier stage of transparent, Of the 23 sites, 14 are located along some resinous-brownfluorite seemsto be over- type of anticlinal structure, either a major grown by a later stage of opaque, light- anticline such as the GuadalupeRidge and purple fluorite. In thin section the fluorite Reef anticlines or a minor anticlinal struc- can be seen to penetrate the limestone for ture (the anticlines of the Waterhole an- as much as 2.5 cm. A fluorite samplecol- ticlinorium and/or bioherms of the FIGURE S-Entrance to Devil's Den adit (DDM) lected for analysis was found to be en- Carlsbad fold complex); five are along Ba- near the western Dog Canyon escarpmentof riched in chromium comparedwith other sin and Range faults in the westem es- the GuadalupeMountains Photo by Ransom Turner. mineral deposits in the area (Table 1). carpment part of the Guadalupe The fluorite exposed in Glori Cave is Mountains; and the remaining four sites one of a few reports of this mineral in the seem unrelated to structure. tively high amounts of vanadium and zinc GuadalupeMountains. King (19t18,p. 160) (Table 1). Veins of black to red, resinous reported crystals of blue fluorite dis- Mineralogy and trace-elementanalyses sphalerite are exposed in the shaft and persed "here and there" in vugs of the Grab samples of the most mineralized- are about 0.3 m (1 ft) wide and trend 350'. Pinery (or Hegler) Member of the Bell looking rock were collectedfrom L6 of the The whole area around the prospect is Canyon Formation in the vicinity of Pratt 23 sites(Table 1). Usually only pyrite and hematized, and rock textures varv from Lodge, McKittrick Canyon. King's site was sphalerite are identifiable as minerals spongy to boxwork to densely missive. visited, but no fluorite could be found, within the deposits, with the exception of In some cases mineralization fills spaces possibly becausethis area has been badly the Two Ladies prospect, which contains between breccia fragments. Gangue cal- hacked up by geologists over the years. galena. Barite and fluorite are uncom- mon, and gangue calcite is common but not ubiquitous. Metal enrichment con- sistsprimarily of iron, zinc,Iead, and cop- per; silver content is low (Table1).

Sulfur-isotope analyses Sulfur-isotope values of the sulfide minerals in the Guadalupe Mountains, as compared with other sulfide deposits around the Delaware Basin and with na- tive sulfur depositswithin the basin, are shown in Fig. 2. These depositshave a relatively narrow rangeof values(615: - 9 to +5) regardlessof their geographicpo- sition within or around the basin. There is one exception to this rule: the sphalerite from the Buck zinc prospect, Apache Mountains, Texas(DeS: - 15 to - 14). The sulfur-isotope values of sulfide minerals around the Delaware Basin are within the samerange as values of native sulfur depositswithin the basin (D}*S:- 15 to + 1.0, Fig. 2). These depleted sulfur- isotope values are characteristicof biolog- FIGURE 6-Pyrite filling fine fractures in Seven Rivers Formation bedrock, Devil's Den Spring ically fractionated sulfur (Davis and Kirk- area, Guadalupe Mountains Photo by Carol Hill. land, 1970).In contrastto theselight values

New Mexico Ceology August 1,993 6l TABLE 1-Trace-element analyses(parts per million) of selectedgrab samples.Delaware Basin. Chemical analysesperformed by Chemex Labs using the aqua regia digestion method. Where values for a mine/prospectare from both this study and another study, the values in parenthesesrepresent the other study.

Symbol Ag As Ba Bi Cd Co Cr Cu on Figs. Trace-elementdetection limit (ppm) Mine/ProspecVOccurrence l, 3, and 7 Location 0.2 27020.5 111

Guadalupe Mountains Golden Eagle mine GE SW'/+sec. 14 T21SR25E r.4 <5 480 10 <0.5 7 77 (2.5t7o)

Rocky Arroyo prospect RA SEr/+sec. 26T2lSR24E <0.2 250 150 2 <0.5 <5 15 270 (thucholite pellets) Little Walt prospect LW SWIL sec.2T275 R24E 0.2 20 9n <2 <0.5 <1<13 Jurnigan gossan lG SWr/r sec. 8 T24SR26E 0.6 295 140 <2 8.0 3 70 263 Guadalupe Ridge GR NEr/+ sec. 33 T25SR22E 5 150 - 0.3 5 100 <5 (pyritic Yates sandstone) Fir Canyon prospect FC NE1L sec.36 T25SR21E <0.2 134 70 72 >100 10 54 7770 Queen of Guadalupes mine QG NE1/+sec. 1 T265R21E 0.2 70 860 <2 18.5 <1 72 45 Cottonwood Cave CWC NE1L sec. 6 T263 R22E 0.4 10 10 <2 0.5 7 4 5800 (pyritic Yates sandstone) Lonesome Ridge LR NEl/r sec.13 T265R21E 0.5 210 50 - 52.0 - 100 30 (pyritic Yates sandstone) Lucky 13 prospect L13 SE'/+sec. f5 T265R21E <0.2 775 30 10 9.0 54591 Devil's Den adit DDM NWr/a sec. 2I T265 R27E <0.2 82 10 <2 <0.5 <1 30 828 Broken Horseshoe claim Devil's Den road prospect DDP SWl/e sec. 2l T263 R2IE <0.2 20 90 <2 6.5 10 779 49 Calumet and Tejas mine CT Latitude:31" 58' 40' 12.8 390 30 506 30.0 35 10 (8.857") Longitude:f04'50'55" Grisham Hunter prospect GH Latitude:31" 58' 14" <0.2 660 20 <2 >100 <1 23 26 Longitude:104'48' 00" Bell Springs prospect BS Latitude: 37" 56' 37' <0.2 45 30 <2 32.5 <1 19 13 Longitude: 704" 48' 52' Glori Cave GC Latitude: 31" 53' 30' 0.2 <10 120 4 7.0 8 158 772 (fluorite) Longitude: 104"51'38' Apache Mountains Seven Heart Gap barite mine MG Latitude: 104"30' 06" 2-0 <500 50% <10 <50 <5 <2 (Main quarry) Longitude: 37" 15'36' Buck zinc prospect BZ Latitude: 104"26' 41' 0.4 20 40 42 (27") 27 47 9 Longitude: 37" 12'24' Glass Mountains Bird mine BD Latitude: 103"30' 51' 16.8 1000 2630 <2 >100 12 22 56 (north section) Longitude: 30" 20' 42' Bissett mine BT Latitude: 103"25' 09' 1.6 <5 30 <2 12.5 254 77 5720 Longitude:30'23'25' Fort Stockton Los Nietos (core) LN Sec.11 Block26, (galena, sphalerite) University land Texas Gulf TG Latitude: 102" 42'55' 24.0 3360 <10 <2 7.0 179 1805 (oil tar with chalcopyrite) Longitude:31'01' f8" are the verv heavv values (635:+40 to cite (BZ) and Devil's Den calcite (DDP), This mineralogy and metal enrichment are +50) of the barit6 at the Queen of the both of which are located within the ther- typical of MVTs (Ohle, 1959). Guadalupes mine and Lechuguilla Cave mal-sparfield and along a Basinand Range (2) The mineralization is epigenetic not entrance.Such values are tvoical of a closed fault zone. syngenetic. Probable time of mineraliza- systemwhere the residuaisulfate has be- tion is Oligocene-Miocene not Late Per- come enriched in the heavy isotope of sul- mian. Hill (1992)considered the mineral fur relative to the isotopically lighter sulfide Mississippi Valley-type ore deposits deposits around the Delaware Basin to be minerals. The sulfide depositsin the Guadalupe Oligocenein age (40-30 Ma), but based Mountains are consideredto be Missis- on the results of this studv (someof the sippi Valley-type (MVT) deposits. The mineral depositsare assoiiatedwith the Carbon

August 1993 Nan Merico Geology relatively uniform (Figs. 2 and 3), no mat- TABLE 1----continued ter where the deposits are located in the DelawareBasin (Fig. 1). This stronglyim- deposits Mo Ni PbScSTUV WZn plies that these are genetically Trace-elementdetection limit (ppm) relatedand have a common origin. 11 271 10 1 102 Reference (2) Sulfur-isotope values of sulfides in the basin (e.g., YesoHills pyrite) are nearly identical to those in the basin-forereef 2590 40 39 10 67 r0 2r3 Soul6(1956) margin (e.g., Bell Springssphalerite and This study McKittrick Canyon pyrite) and to those in 130 765 310 <1 30 (2.35V") <1 <5 30 Waltman (1954) backreefstructural and stratigraphic traps This study high in the mountains (e.g., Grisham <1 9 40 2 49 <10 148 <5 100 This study Hunter sphalerite).This suggestsa ge- 279 6 184 2 AA <10 233 <10 r665 This study netic connection between mineral depos- <10 5 300 30 15 Light & Domenico its in the basin and those in the reef. (1e83) (3) Sulfur-isotope values of sulfides in the Guadalupe Mountains are similar to 70 82 8000 3 40 <10 JJ 10 3230 This study sulfur-isotope values of native sulfur in 734 242 <10 75 <10 <5 92 2700 This study the basin (Fig. 2). This also implies a ge- 1 5 4210 <10 4 <10 27 <5 332 This study netic connection between basin and reef. (a) The structural and stratigraphic po- 20 30 300 50 - 2200 Light & Domenico sition of the sulfide mineralization in the (1e83) GuadalupeMountains is the sameas that 22 9 2370 5 <10 943 <50 5510 This study of the caves(Fig. 7). Becausecaves in the 2 1 30r 45 <10 5 <10 70 This study Guadalupe Mountains were dissolved by sulfuric acid derived from HrS basinal de- 15 75 1275 5 <10 133 <50 7210 This study gassing(H1ll,1987,1990), it is not illogical basinal HrS may have also 13 36 (2.3570\ 140 73 20 575 635 (>i%a) King (1948) to suspect that This study supplied the reduced sulfur necessaryfor the sulfide deposits in the Guadalupe 15 72 13 <10 486 <10 6210 This study Mountains. The following scenario is proposed for IJ 40 <10 292 20 3740 This study the origin of sulfide mineralization in the GuadalupeMountains. In the Oligocene- 14 62 510 <10 22 <5 310 This study Miocene, as the DelawareBasin was being faulted, uplifted, and heated, hydrocar- bon migration into Castile Formation <2 <5 - <10 7000 <200 Murray (1978) evaporites in the basin produced HrS gas that oxidized to native sulfur (e.9., the 2 7770 25 370 66 t20 (3470\ Udden (1914) Culberson sulfur mine, Fig. 2) or as- This study cended reefward where it accumulatedin structural and stratigraphic traps (Fig 7A) 80 >1% 485 <10 60 >l% This study Metals moving as chloride complexes downdip from backreef evaporites formed 2 206 152 <10 26 135 This study sulfide minerals in the reduced zone wherever they came in contact with this trapped HrS gas. Later, in the Pliocene- 6000 6.6% Mazzullo (1986) Pleistocene,as the water table dropped, HrS migrating into these same traps be- 8690 1770 1990 | 409 70 277 <5 78 This study came oxidized to sulfuric acid at or near the water table (Fig. 7B). The sulfuric acid then dissolved out the large cavepassages in the GuadalupeMountains. (4) All of the sulfide deposits in the eastern,Fort Stockton,side of the Dela- This scenariois consistentwith the four Guadalupe Mountains are located along ware Basin;sulfur-isotope values of these piecesof evidencelisted above.The sul- the margin of the basirywithin 20 km (12.5 deposits match those ih the Guadalupe fides and native sulfur around and in the mi) of the basin edge (Fig. 1). MVT de- Mountains (Fig.2). North and Mclemore basin are isotopically similar becausethey posits generally are found in carbonate (1985,1988) classified the mineral depos- have the same source of light gas-that rocksnear the marginsof sedimentaryba- its in the Guadalupe Mountains as MVTs is, HrS generated from hydrocarbon re- sins (Ohle, 1980). basedon their mineralogy,host rocks,form actions in the basin. Sulfur isotopesare (5) The sulfide depositsin the Guada- of deposits, tectonic setting, and genetic similar from basin to basin margin to lupe Mountains are in structural and Process. backreef becausethey also had this same stratigraphic traps. This is typical of MVT source of light gas and becausethe mi- deposits,which aregenerally in structural Origin of sulfide deposits in the gration path for the gas was from basin and./orstratigraphic traps (i.e., as "manto" Guadalupe Mountains to basin margin to reef to backreef (Fig. depositsbelow impermeablebeds or along Four pieces of evidence are crucial to 7A). Finally, the sulfides and caves oc- anticlinesor faults; Ohle, 1980). understanding the origin of the MVT sul- cupy the same structural and strati- (6) Other workers havealso considered fide deposits in the Guadalupe Moun- graphic position becausein eachcase H2S thesedeposits to be of the MississippiVal- tains: accumulated in the same traps-the sul- ley type. Mazzullo (1986)found MVT sul- (1) The sulfur- and carbon-oxygen-iso- fides at an earlier time when these gas fides in Lower Permian dolomites on the tope values of the mineral deposits are traps were in the reduced zone and the

New Mexico Ceology August 1993 @ olreocENE-MtocENE(4o-2oMo )

+l+ WATERTABLE

Evoporite foci es

Cosfi le Fm.(onhydrife) =u{ Siie of notive sulfur deposiiio n

g+CoCOiH2O BelI Conyon Lomor Mbr

@ elroceNE-pLEtsrocENE(5-o Mo)

TonsillFm oftffi| o.: r" - WATER Solufion-subsidence -WATEEga_i€r surfoce of GypsumPloin YH pyrile Coxorovel : rem-nonls

CostileFm Notivesulfur

FIGURE 7-Idealized model for the formation of sulfide ore deposits, Guadalupe Mountains. This model proposes a genetic connection between hydrocarbons, native sulfur and pyrite in the basin, and Mississippi Valley-type(MW) deposits and caves in the carboiate-reef margin. (A) In the Oligocene-Miocene, during the initial uplift of the Delaware Basin, HrS wai-generated in the basin by reactions involving hydrocaibons and the Castile anhydrite. The HrS oxidized to native sulfur in the basin and also migiated from basin to reef io accumulate there"in itructural (anticlinal) and stratigrap^hic (base_of Yates) traps. Metals moved downdip as chloride coirplexes from backreef-evaporite facies, and where they met with the ascending HrS below the water table in the zone of reduction, they formed MVT deposits. (B) In the Piiocene-Pleistocene continued uplift of the Guadalupe Mountains and basin caused increased HrS generation ind migration of las from basin to reef. Cave dissolution occurred in the same structural and stratigraphic position as earlier MVT deposits; cave passageJ were disJolved where H2S oxidized to sulfuric acid at or near the water table in the zone of oxidation. Cave levels correspond to a descending bise level. Symbols used are the same as those used in Fig. 1 caption.

cavesat a later time when thesetraps were Guadalupe Mountains may have had as AcrNowr-sDGME\[+This research was in the oxidized zone (Fig. 7). their source of reduced sulfur H2S gas funded by a grant from the New Mexico generated in the basin. Bureau of Mines and Mineral Resources. Summary (4) Sulfur-isotope values support the Guadalupe Mountains National Park, (1) The sulfide-mineral deposits in the concept that HrS generated in the basin Carlsbad Caverns National Park, Lincoln Guadalupe Mountains are not extensive was the source of reduced sulfur for the National Forest, and the Bureau of Land and have never been economically prof- native sulfur depositsin the basinand for Management permitted sample collection itable. Mineral-assessmentevaluaiion of the MVT mineral deposits around the on their lands. Sulfur-isotope analyses the deposits is L/C-low potential with a margins of the basin. were performed by Geochron Labs, and IevelC of certainty(Hansen, 1991,pp.95- (5) The sulfide depositsin the Guada- carbon-oxygen-isotopeanalyses were e7). lupe Mountains are consideredto be of performed by Geochron Labs and by A. (2) The mineral deposits and the caves the Mississippi Valley type. Campbell and C. Wolf, New Mexico In- of the GuadalupeMountains occupy the (6) The model of origin proposed for stitute of Mining and Technology. Che- same structural and stratigraphic posi- MVT deposits in the Delaware Basin may mex Labs performed the trace-element tion. Thesecaves were dissolvedby sul- apply to other basins;i.e., MVTs may be analyses.I would especiallylike to thank furic acid derived from HrS migrating from related to the degassing of basins rather C. Mosch and R. Turner for their contin- basin to reef. than the compaction and dewatering of ued field support and V. Mclemore and (3) Likewise, the sulfide deposits in the basins (Hill, L993a,b). R. North for their helpful comments.

August 1993 NatsMexico Geology References Valley-typeore deposits, ProceedinSsvolume: Uni- Munay, D. L., 1978,Barite deposits in the SevenHeilt Anderson, R. Y., 1981, Deep-seatedsalt dissolution ve$ity of Missouri-Rolla Prcss, Rolla, Missouri, pp. Gap area, Culberson County, Texas: Unpublished in the Delaware Basin, Texasand New Mexico; ln 721-'t32. MS thesis, University of Texasat Austin, Austin, Wells,S. G., and Lambert,W. (eds.),Environmen- Jagnow,D. H.,1977, Ceologicfactors influencing spe- Texas,55 pp. tal geology and hydrology in New Mexico: New leogenesisin the Capitan reef comPlex,New Mex- North, R. M., and Mclemore, V T., 1986,Silver and Mexico Geological Sociery,Special Publication 10, ico and Texas:Unpublished MS thesis, University qold occurrencesin New Mexico: New Mexico Bu- ResourceMap PP.133-145. of New Mexico, Albuquerque, New Mexico, 197pp. ieau of Mines and Mineral Resources, Davis,J. 8., and Kirkland,D. W., 7970,Native sulfur Jagnow,D. H.,7989, The gmlogy of t"echuguillaCave, 15,32 pp., scale1:1,000,000. deposition in the Castile Formation, Culberson New Mexico; in Harris, P. M., and Grover, G. A. North, R. M., and Mclemore, V T., 1988,A classi- County, Texas:Economic Geology, v. 55, pp. 107- (eds.), Subsurfaceand outcrop examination of the fication of the precious metal deposits of New Mex- 12L. Capitan shelf rnargin, northern DelawareBasin: So- ico; in Schafer,R. W., Cooper, f. J., and Vikre, P Finch, W. 1., 1972,Uranium in easternNew Mexico; ciety of Economic Paleontologistsand Mineralo- G. (eds.), Bulk mineableprecious metal depositsof in Kelley, V. C., and Trauger, F. D. (eds.), East- gists, Core Workshop 13, pp.459-456. the western -symPosium proceed- cenkal New Mexico: New Mexico Geological So- King, P 8., 1930,The geologyof the GlassMountains, ings: GeologicalSociety of Nevada, pp. 625-659. ciety, Guidebook to 23rd Field Conference,pp. 171- Tens, Part I, Descriptive geology: University of Texas Ohle, E. 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New stone buttes, Gypsum Plain, Culberson County, genesis of sandstonedikes, Capitan Limestone, New Mexico and Texas:New Meiico Bureauof Mines Texas:American Association of Petroleum Geolo- Mexico: Unpublished MS thesis,Sul RossState Uni- and Mineral Resources,Bulletin 117, 150 pp. gists,Bulletin, v. 50, no. 11, pp. 2005-2018. versity, Alpine, Texas,112 pp. Hill, C. A., 1988,Fluorite in Glori Cave,Guadalupe Kyle, l. R., 1990,Barite deposits of the DelawareBa- Price,J. G., Henry, C. D., and Standen,A. R., 1983, MountainsNational Park:Cave ResearchFounda- sin, westTexas;inKyle,l. R. (ed.),Industrialmin- Annotated bibliography of mineral deposits rn Trans- tion, Annual Report30, p. 22. eral resources of the Delaware Basin, Texas and PecosTexas: University of Texasat Austin, Bureau Hill, C. 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(ed.), Southeastern New America,Abstracts with Programs,v.25, no.3, p. duction, and resources,with selectedbibliography: Mexico: New Mexico Geological Society, Guide- 26. New Mexico Bureau of Mines and Mineral Re- book to 5th Field Conference,pp. 113-114. Hill, C. A., 193b, A hydrogen sulfide, basinal-de- sources,Open-file Report 183, 180pp. Wood, J. W., 1968, Geology of Apache Mountains, gassing model for the origin of Mississippi Valley- Motts, W 5., 7962, Geology of the West Carlsbad Trans-PecosTexas: Universitv of Texasat Austin, type ore deposits; r't Shelton, K. L., and Hagni, R. quadrangle, New Mexico: U.S. GeologicalSurvey, Bureauof EconomicCeology,'Geologic Quadrangle D. (eds.), Geology and geochemistryof Mississippi Geologic Quadrangle Map GQ-157, scale1:62,000. Map 35, 32 pp., scalel:63,360. !

New Merico Ceology August 1993