32 research outputs found
Can isoprenoids in leaves and roots of plants serve as biomarkers for past vegetation changes? A case study from the Ecuadorian Andes
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Rock-Eval pyrolysis and organic petrographic analysis of the Maastrichtian coals and shales at Gombe, Gongola Basin, Northeastern Nigeria
No full textHydrocarbon generation modeling and source rock characterization of the Cretaceous–Paleocene Taratu Formation, Great South Basin, New Zealand
No full textOrganic petrography, Rock–Eval pyrolysis and biomarker geochemistry of Maastrichtian Gombe Formation, Gongola Basin, Nigeria
No full textEvolutionary stasis of sporopollenin biochemistry revealed by unaltered Pennsylvanian spores
No full textDistribution and geochemical significance of dibenzofurans, phenyldibenzofurans and benzo[b]naphthofurans in source rock extracts from Niger Delta basin, Nigeria
No full textSource rock characterization and hydrocarbon generation modeling of the Middle to Late Eocene Mangahewa Formation in Taranaki Basin, New Zealand
No full textThe nature and fate of natural resins in the geosphere. Part X.<sup>†</sup>Structural characteristics of the macromolecular constituents of modern Dammar resin and Class II ambers
Get PDF<p/> <p>As part of a larger study of the structure and behavior of polyterpenoids in sedimentary systems, the structural characteristics of the macromolecular constituents of Dammar resin and a related Class II amber have been reinvestigated. The conclusions drawn from these analyses are inconsistent with the current widely held "polycadinene" model for the macromolecular structure of these materials. Double bond characteristics observed by one and two dimensional NMR spectroscopy do not match those in the proposed "polycadinene" structure. Based on these observations it is suggested that the proposed "polycadinene" structure for these materials is inadequate and requires revision. Elemental and NMR data also suggest a significant contribution from functionalized monomers.</p
