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Title: Radiocarbon, sup 13 C and sup 15 N analysis of fossil bone: Removal of humates with XAD-2 resin

Journal Article · · Geochimica et Cosmochimica Acta; (USA)
 [1]; ;  [2]
  1. Carnegie Institution of Washington, DC (USA)
  2. Univ. of Arizona, Tucson (USA)

Humic acids are the predominant source of error in the {sup 14}C and stable isotope analysis of fossil bone organic matter. XAD-2 resin will quantitatively remove humates and give the highest yields of protein from bones with variable types of preservation. Decalcified bone, gelatin and base-leached residues can vary up to 5{per thousand} for {delta}{sup 13}C and by 1{per thousand} on {delta}{sup 15}N relative to XAD-treated fractions. Simultaneous analysis of {sup 14}C age, {delta}{sup 13}C and {delta}{sup 15}N is recommended because each isotope value can be independently affected by the bone's diagenetic history. Radiocarbon analysis is the most sensitive and {delta}{sup 15}N is least sensitive for detecting exogenous organic matter. The uncertainty of analyses on the best pretreated protein is {plus minus} 0.5{per thousand} for both {delta}{sup 13}C and {delta}{sup 15}N and is larger than previous estimates. The accuracy for all isotope analyses will be better assessed by using individual amino acids instead of total collagenous residues. Inaccurate {sup 14}C dates on severely degraded bone are an indication that this class of fossils may be unsuitable for any isotopic analysis.

OSTI ID:
5151954
Journal Information:
Geochimica et Cosmochimica Acta; (USA), Vol. 52:9; ISSN 0016-7037
Country of Publication:
United States
Language:
English