New Mexico Geological Society Annual Spring Meeting — Abstracts

variation of several paleoenvironmental and geochemical parameters have been determined on samples from a 303.4 ft, continuous core and correlated outcrops from the Late Cretaceous Fruitland Formation in the Fossil Forest study area, San Juan Basin, New Mexico. Fossil
resin occurs throughout the sequence in association with coal, sandstone, shale and petrified wood. The infrared spectra and trace element concentration in fossil resin has been related to those parameters. In addition to palynological studies, mineralogy of the whole rock and <2 micron fraction were determined by X-ray diffraction. Trace element concentrations were determined by atomic absorption.

Trace element content of the resin is thought to be independent of allocthonous affects. Concentration of these elements in the resin, therefore, depends on the biogeochemical environment at the time of deposition. Some elements are concentrated in the resin relative to the associated coals; some are depleted. Infrared spectra of resins from througbout the sequence reveal differences attributable to oxidation and botanical origin.