ANTELOPE WELLS

(EL BERRENDO)

SOUTHWESTERN NEW MEXICO

AND

NORTHWESTERN CHIHUAHUA

Collected from: Sections 9,10,11,12,13,14,23,24 (and area adjacent sections 23 and 24 in Chihuahua) R17W, T34S USGS Whitewater Mountains 7.5' Quad, south central Hidalgo County, New Mexico and adjacent Chihuahua where the source is colloquially known as El Berrendo.

Findlow and Bolognese describe Antelope Wells as "a point source" with apparently little secondary dispersion (1982:57). They state that the nodules are located in the Clanton Draw drainage in the Peloncillo Mountains (Findlow and Bolognese 1982:57). Two days of survey in the Clanton Draw locality failed to yield any vitreous obsidian. The only glass recovered was devitrified vitrophyre. Unfortunately, the primary source at Deer Creek could not be investigated since New Mexico Hwy 79 is permanently closed by Gray Ranch Properties. However, nodules were recovered as secondary deposits in the lower Deer Creek drainage and in alluvium east and south of the Animas Mountains. Zeller (1962) records "nodular obsidian inclusions" in the OK-Bar Conglomerate along the upper Deer Creek drainage in the southern Animas Mountains. This is located in, at least, Sections 11,12,13,14 R19W, T33S of USGS San Luis Pass 7.5' Quad.

While Findlow and Bolgnese may be correct in that the Deer Creek primary source is "a point source" (1982:57), the nodules are distributed at least 15 to 20 km east and south into Chihuahua. If nodules occur in the nearby Peloncillo Mountains as stated by Findlow and Bolognese, the source stretches considerably farther west, perhaps into Arizona. The density of the nodules ranges up to 5 per 5 m2 and is likely much higher upstream. Nodule diameters in the alluvium reached 6 cm and Findlow and Bolognese report sizes up to 15 cm (1982:57). The material is an excellent medium for tool production, certainly equal to the other mid-Tertiary marekenites of Arizona. The cortex on the alluvial specimens is smooth black through velvet black. The color of the aphyric glass covers a similar spectrum as Sauceda; in fact they are nearly identical megascopically. Translucent brownish-green is common, but dark gray, green/brown banded and opaque black colors also occur. Nodules were reduced everywhere in the alluvial deposits, but the low density (<1 per 10 m2) reflects the low geological occurrence.

[updated 1995] In the original study, geologic investigations were hampered by land closures at the source (Shackley 1988). An important observation was that contrary to the Findlow and Bolognese (1982) study, no artifact quality marekenites could be located in the Peloncillo Mountains, and there was considerable secondary dispersion of the nodules in the area (Shackley 1989: 201-202). An important new study of this source by LeTourneau (1994) amplifies this observation and provides useful insight. LeTourneau's intensive study of the geology and petrology with access to the OK Bar Conglomerate and Deer Creek, indicate that this is a rather typical Tertiary peralkaline glass source with a probable rhyolite formation origin and attendant secondary deposition (LeTourneau 1994). LeTourneau did find marekanites in situ in tuff and conglomerates, and volcaniclastics of Culberson Ranch (Tvcr; 1994:4). No nodules were located in perlitic lava. Nodule sizes, however, located by LeTourneau are about the same size as those reported in my original survey (up to 6 cm), but the extent of the deposit is much greater.


Elemental concentrations for Antelope Wells source standards. Those samples with "A" prefixes from Shackley, all others collected by LeTourneau. All measurements in parts per million (ppm).

SAMPLE Ti Mn Fe Rb Sr Y Zr Nb Ba Pb Th
1B1  1512 1184 25863 372 6 131 1275 101      
5B3  1190 966 22438 345 6 133 1222 93      
7B1  1367 1097 24538 381 8 137 1316 106      
7B3  1410 1024 23250 361 7 136 1285 102      
7B8  1381 1018 22291 357 5 133 1276 98      
7B12  1405 1117 25989 392 9 143 1357 109      
8H1  1282 945 22076 342 5 124 1215 96      
8I1  1392 1102 24950 381 6 140 1310 100      
AW1  1413 1091 24241 374 9 128 1329 105 45    
AW2  1433 995 22222 341 8 123 1250 96 45    
AW3  1405 1020 22298 340 7 126 1265 91 47    
AW4  1284 919 20920 332 9 124 1235 95 45    
AW5  1393 963 21459 342 6 124 1230 92 42    
AW6  1325 864 20616 326 7 121 1203 96 48    
AW7  1213 770 18126 303 6 119 1179 94 52    
AW8  1583 1096 25810 377 8 132 1337 104 44    
AW9  1553 1031 23912 355 8 127 1275 95 44    
AW10  1309 937 21317 333 9 126 1247 98 45    
AW11  1706 1010 21325 322 5 124 1228 94 47    
AW12  1392 894 21632 336 8 127 1227 92 43    
AW13  1244 854 20459 333 7 122 1222 92 47    
AW14  1257 927 22337 350 9 123 1251 100 45    
AW15  1500 919 21240 323 7 122 1204 92 46    
AW16  1375 906 21151 329 6 123 1195 90 41    
AW17  1254 925 22557 353 7 126 1247 96 46    
AW18 1522 905 21242 340 10 130 1212 101 <1 44 43
AW20 1442 813 20768 339 8 132 1216 105 <1 40 46
AW21 1309 729 18040 300 8 125 1113 96 6 38 43
AW22 1439 823 19997 324 8 135 1181 105 19 39 40
AW23 1858 1152 26832 388 8 146 1312 114 <1 55 59
AW24 1306 673 17162 289 8 123 1088 92 1 36 44
AW25 1186 638 16512 292 9 120 1077 98 <1 37 43
AW26 1415 793 19914 328 10 126 1178 98 <1 41 40

 

Mean and central tendency for data in table above

 

SONORA UNKNOWN A AND ANTELOPE WELLS

During an obsidian provenance study for Sean Dolan (University of Oklahoma) on Casas Grandes (CG) outlier sites in northern Chihuahua, one artifact produced from this source was discovered from the Whalen/Minnis Site 315 (Shackley 2014).  The one artifact produced from Sonora Unknown A from Site 315 is a source seen fairly frequently in the border region.  With a relatively high concentration of Rb and very low Sr it is distinctive, but until now unlocated (Shackley 2005:85, Table A.17).

From Shackley (2005:85): SON Unknown A. "In 1997, 1999, and again in 2002, three archaeological projects in extreme southern Arizona on the border near Douglas, Arizona revealed the same set of elemental concentrations in some of the archaeological obsidian that does not match any known sources on either side of the border (Shackley 1997, 1999, 2002).  This obsidian exhibits a relatively high Rb content over 300 ppm, and very low Sr (see Appendix).  This source is provisionally called SON Unknown A (see Appendix for data)."

Additionally, one of the "unknown" source groups in the CG outlier sites called "Chihuahua Unknown B" comprises 10% of the artifacts in the assemblage, has been seen as far north as Fort Huachuca, Arizona and in Mimbres sites north of the border (Jeff Ferguson, personal communication, 2014; Craig Skinner, personal communication, 2014).  It has an elemental composition similar to Antelope Wells, but with a much lower concentration of zirconium and slightly higher niobium.  It is possible that this compositional group is the result of a co-genetic relationship with Antelope Wells, but is not always found in association with Antelope Wells obsidian, and redundant surveys by myself, Phil LeTourneau, and Office of Contract Archaeology staff, University of New Mexico, and my analyses of all these collections from both sides of the border at Antelope Wells has never detected this chemical group.  Nevertheless, it is possible it is related to Antelope Wells and may be from a small dome complex nearby that has remained undetected.  The Gray Ranch that owns much of the property in the area did not allow any research on their property historically.  Both Chihuahua Unknown A and B given their presence in sites north of the border are likely sources near the border region.  Time will tell.

In order to see if this unlocated source might be in the Antelope Wells area, I analyzed samples from my 1980s collection that had not been analyzed (samples A18-26 in table above), and while the Chihuahua Unknown B group was not evident, one marekanite had the "Sonora Unknown A" composition (see below).  Findlow and Bolognese (1982) noted marekanites in the Peloncillo Mountains west of Antelope Wells on the Arizona/New Mexico line, but my surveys in the 1980s did not discover anything but vitrophyres.  It is certainly possible that Sonora Unknown A is located in this area. I call this source provisionally "Animas Mountains".

 Elemental concentrations for one marekanite recovered at Antelope Wells (AW19) and Sonora Unknown A samples from archaeological contexts north of the border (Shackley 1997, 1999, 2002).  Ba, Pb, Th not analyzed in the archaeological studies.

Sample

Mn

Fe

Rb

Sr

Y

Zr

Nb

Ba

Pb

Th

AW19

631

10138

329

8

76

199

52

<1

23

26

Sonora Unk A

663

9744

292

3

56

173

41

 

 

 

Sonora Unk A

667

9599

325

4

59

189

43

 

 

 

Sonora Unk A

687

9796

316

1

61

190

45

 

 

 

Sonora Unk A

678

9461

313

2

57

187

44

 

 

 

Sonora Unk A

884

11341

365

0

68

208

53

 

 

 

Sonora Unk A

629

9225

288

0

61

161

32

 

 

 

Sonora Unk A

674

9569

326

3

69

211

42

 

 

 

Sonora Unk A

706

9718

307

3

55

186

40

 

 

 

REFERENCES CITED 

Findlow, F.J. and M. Bolognese, 1982, A preliminary analysis of prehistoric obsidian use within the Mogollon area.  In P.H. Beckett (Ed.) Mogollon Archaeology: Proceedings of the 1980 Mogollon Conference, pp. 297-316.  Ramona, California: Acoma Press.

            LeTourneau, P.D., 1994, Geologic investigations of the Antelope Wells obsidian source, Southern Animas Mountains, New Mexico.  Paper presented at the 59th annual meeting of the Society for American Archaeology, Anaheim.

            Shackley, M.S., 1988, Sources of Archaeological Obsidian in the Southwest: An Archaeological, Petrological, and Geochemical Study.  American Antiquity 53:752-772.

            Shackley, M.S., 1989, Early Hunter-Gatherer Procurement Ranges in the Southwest: Evidence from Obsidian Geochemistry and Lithic Technology. Ph.D. dissertation, Department of Anthropology, Arizona State University.

Shackley, M.S., 1997, An energy-dispersive x-ray fluorescence (EDXRF) analysis of obsidian artifacts from AZ FF:12:48 (ASM) southeastern Arizona.  Report prepared for Pat Gilman, Department of Anthropology, University of Oklahoma, Norman.

Shackley, M.S., 1999, An energy-dispersive x-ray fluorescence (EDXRF) analysis of obsidian artifacts from the Boss Ranch Site (AZ FF:7:10 ASM), Cochise County, southeastern Arizona.  Report prepared for John Douglas, University of Montana.

Shackley, M.S., 2002, Source provenance of archaeological obsidian from Mimbres Mogollon sites in the Cedar Mountains, southwest New Mexico.  Report prepared for the Bureau of Land Management, Albuquerque, New Mexico.

Shackley, M.S., 2005, Obsidian: Geology and Archaeology in the North American Southwest.  Tucson: University of Arizona Press.

Shackley, M.S., 2014, Source provenance of obsidian artifacts from the Casas Grandes Outlier Sites 204, 242, and 315, Northern Chihuahua. Report prepared for Sean Dolan, Department of Anthropology, University of Oklahoma, Norman.

Zeller, R.A., 1962, Reconnaissance geologic map of the Southern Animas Mountains.  New Mexico Institute of Mining and Technology, Socorro.

This page maintained by Steve Shackley (shackley@berkeley.edu).
Copyright 2014 M. Steven Shackley. All rights reserved.
Revised: 19 August 2015

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