title: Isotopic composition of hydrogen in insoluble organic matter from cherts.
abstract: Robert (1989) reported the presence of unusually enriched hydrogen in the insoluble HF-HCl residue extracted from two chert samples of Eocene and Pliocene ages.  Since the presence of heavy hydrogen might be due to the incorporation of extraterrestrial materials, we desired to reexamine the same samples to isolate the D-rich components.  Our experiments did not reveal any D-rich components, but the hydrogen isotope composition of the insoluble residue of the two chert samples was well within the range expected for terrestrial organic matter.  We also describe a protocol that needs to be followed in the hydrogen isotope analysis of any insoluble organic matter.
authors.affiliation: Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125.
authors.forename: R V
authors.initials: RV
authors.lastname: Krishnamurthy
authors.forename: S
authors.initials: S
authors.lastname: Epstein
mesh_terms: D003903:Deuterium / Q000032:analysis*; D006851:Hydrochloric Acid / Q000032:analysis; D006858:Hydrofluoric Acid / Q000032:analysis; D006859:Hydrogen / Q000032:analysis*; D007554:Isotopes; D010163:Paleontology; D011791:Quartz / Q000737:chemistry*; D013696:Temperature
chemical_list: D007554:Isotopes; D011791:Quartz; D006859:Hydrogen; D003903:Deuterium; D006851:Hydrochloric Acid; D006858:Hydrofluoric Acid