Los Jagüeyes

Located on a distributary of the Rio Santa Maria, probably an earlier channel of the river, is a secondary source of marekanites that exhibits at least two source groups based on elemental composition. One of the source groups appears to be the Sierra Fresnal primary source which is actually located about 60 km north of Los Jagüeyes and not along the same drainage system, and actually downstream from Los Jagüeyes (see data in Appendix). Again, this is a typical pattern in northwest Mexico frustrating the accurate delineation of obsidian sources. Marekanites up to 50 mm in diameter are located on the lower pebble terrace that contains sub-rounded and rounded marekanites, chalcedony blossoms, and polychrome agate. The area exhibits stone tools including bipolar core fragments of obsidian and 10+ projectile points, many of which look similar to Cienega points and those recovered in Late Archaic/Early Agricultural sites in Chihuahua, Arizona and New Mexico in an area about 100 m in diameter (Hard and Roney 1999). No ceramics were noted. Metate fragments and a portable mortar were also present all produced from vesicular andesite. The density of geological marekanites was up to 1 per 50m2. It is impossible to determine which unreduced nodules were geological and which were cultural. It is possible that the Sierra Fresnal nodules were cultural. An examination of the surrounding hills, that included rhyolite domes, did not reveal any in-situ marekanites. This "source" is located at UTM 13R 0271137/3371028 on the INEGI Malpais H13A72 1:50,000 sheet.

Los Jaguëyes (Raw Data)

SAMPLE

Ti

Mn

Fe

Zn

Th

Rb

Sr

Y

Zr

Nb

Source Group1

1

1486.5

1035.8

28894.1

263.7

29.1

291.4

5.6

160.0

1565.3

131.4

B

2

923.5

185.6

8858.2

30.8

37.5

254.3

31.4

56.6

147.7

28.6

C

3

1567.8

1027.8

28408.6

249.0

31.6

273.8

3.6

154.2

1489.4

119.7

B

4

1751.8

598.7

32526.6

318.0

33.2

290.2

2.7

216.2

2107.1

158.8

B

5

2093.5

1346.0

34294.3

293.9

37.8

281.2

1.7

163.9

1786.7

128.1

B

6

1685.6

1138.0

28660.1

260.2

30.5

273.0

2.9

157.5

1533.2

123.9

B

7

1772.3

1139.0

29188.1

250.6

37.0

265.7

5.6

148.8

1685.3

126.8

B

8

1643.5

1098.1

28621.9

261.9

31.2

268.6

2.9

152.2

1577.0

125.2

B

9

1659.2

1001.9

27357.1

250.5

29.9

272.2

0.6

154.4

1479.6

114.7

B

10

1589.6

1100.7

27495.9

242.1

38.9

262.3

4.6

150.2

1490.3

120.6

B

11

1587.6

932.1

27009.3

245.8

28.8

265.3

3.5

147.3

1412.3

117.2

B

Source groups based on original grouping in the cruciform study (Shackley 1997b). At least some of these samples could be cultural.

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Revised: 21 March 2015