Geochemical Analysis of Eight Red Ochres from Western North America

In this paper, we report on our examination of the suitability of geochemical provenance studies on red ochre sources from western North America. We report geochemical data derived from PIXE (particle-induced X-ray emission) analysis of eight red ochre sources from California, Oregon, Wyoming, and Alaska. Our preliminary analysis of these red ochres, including multiple samples from one large deposit, suggests that the tested samples vary significantly between sources. It appears likely that the geochemical analysis of red ochres, widely used and traded among Native Americans and other ancient peoples around the world, could expand the range of materials used by archaeologists and other scholars to reconstruct past exchange and interaction systems.

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Lithospheric roots beneath western Laurentia: the geochemical signal in mantle garnets

Canadian Journal of Earth Sciences ◽

10.1139/e03-003 ◽

2003 ◽

Vol 40 (8) ◽

pp. 1027-1051 ◽

Cited By ~ 28

Author(s):

D Canil ◽

D J Schulze ◽

D Hall ◽

B C Hearn Jr. ◽

S M Milliken

Keyword(s):

Rare Earth ◽

North America ◽

Trace Element ◽

Earth Element ◽

Geochemical Data ◽

Trace Element Data ◽

Mantle Lithosphere ◽

Western North America ◽

Wyoming Province ◽

Thick Mantle

This study presents major and trace element data for 243 mantle garnet xenocrysts from six kimberlites in parts of western North America. The geochemical data for the garnet xenocrysts are used to infer the composition, thickness, and tectonothermal affinity of the mantle lithosphere beneath western Laurentia at the time of kimberlite eruption. The garnets record temperatures between 800 and 1450°C using Ni-in-garnet thermometry and represent mainly lherzolitic mantle lithosphere sampled over an interval from about 110260 km depth. Garnets with sinuous rare-earth element patterns, high Sr, and high Sc/V occur mainly at shallow depths and occur almost exclusively in kimberlites interpreted to have sampled Archean mantle lithosphere beneath the Wyoming Province in Laurentia, and are notably absent in garnets from kimberlites erupting through the Proterozoic Yavapai Mazatzal and Trans-Hudson provinces. The similarities in depths of equilibration, but differing geochemical patterns in garnets from the Cross kimberlite (southeastern British Columbia) compared to kimberlites in the Wyoming Province argue for post-Archean replacement and (or) modification of mantle beneath the Archean Hearne Province. Convective removal of mantle lithosphere beneath the Archean Hearne Province in a "tectonic vise" during the Proterozoic terminal collisions that formed Laurentia either did not occur, or was followed by replacement of thick mantle lithosphere that was sampled by kimberlite in the Triassic, and is still observed there seismically today.

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Supplemental Material: Nonclimatic and extrabasinal processes controlled pedogenesis in paleosols of the Paleocene Nacimiento Formation, New Mexico, USA

10.1130/gsab.s.14842191 ◽

2021 ◽

Author(s):

Kevin M. Hobbs

Keyword(s):

New Mexico ◽

Statistical Analysis ◽

Analysis Data ◽

Geochemical Data ◽

Geochemical Analysis ◽

X Ray ◽

Data Tables

Geochemical data tables, X-Ray diffractograms from paleosol B horizon materials, and results of statistical analysis of pedotype and geochemical analysis data.

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Supplemental Material: Nonclimatic and extrabasinal processes controlled pedogenesis in paleosols of the Paleocene Nacimiento Formation, New Mexico, USA

10.1130/gsab.s.14842191.v1 ◽

2021 ◽

Author(s):

Kevin M. Hobbs

Keyword(s):

New Mexico ◽

Statistical Analysis ◽

Analysis Data ◽

Geochemical Data ◽

Geochemical Analysis ◽

X Ray ◽

Data Tables

Geochemical data tables, X-Ray diffractograms from paleosol B horizon materials, and results of statistical analysis of pedotype and geochemical analysis data.

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Reduction Strategies and Geochemical Characterization of Lithic Assemblages: A Comparison of Three Case Studies from Western North America

American Antiquity ◽

10.2307/40035862 ◽

2007 ◽

Vol 72 (3) ◽

pp. 585-597 ◽

Cited By ~ 48

Author(s):

Jelmer W. Eerkens ◽

Jeffrey R. Ferguson ◽

Michael D. Glascock ◽

Craig E. Skinner ◽

Sharon A. Waechter

Keyword(s):

North America ◽

Average Distance ◽

Geochemical Data ◽

Small Scale ◽

Western North America ◽

Trade Patterns ◽

Geochemical Composition ◽

Left Behind ◽

Lithic Assemblages ◽

Reduction Strategies

Based on a simple model of lithic procurement, reduction, and use, we generate predictions for patterns in source diversity and average distance-to-source measurements for flaked stone assemblages left behind by small-scale and residentially mobile populations. We apply this model to geochemical data from obsidian artifacts from three regions in western North America. As predicted, results show markedly different patterns in the geochemical composition of small flakes, large flakes, and formal tools. While small flakes and tools tend to have greater source diversity and are on average farther from their original source, the large flake assemblage is composed of fewer and closer sources. These results suggest that a failure to include very late stage reduction (e.g., pressure flakes) and microdebitage in characterization studies may bias interpretations about the extent of residential mobility and/or trade patterns because more distant sources will be underrepresented.

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