in Geological Society of America
Annual Meeting Denver, Colorado, USA, October 25-28,1999
Abstracts with Programs, 31(7): A467
TRIASSIC AMBERS FROM THE
CHINLE USA HELP PROVIDE
PRELIMINARY BIOCHEMICAL LINKS TO THE IDENTITY OF
CONTRIBUTOR PLANTS
Paul T. Kay ptarsuskay@yahoo.com Denver, CO
Sidney R. Ash sidash@aol.com Albuquerque, NM
Two fossil resins or ambers from the Upper Triassic Chinle formation on the
Colorado Plateau in Arizon USA were first studied and reported by Litwin and Ash
(1991). Their study
used Fourier Transform Mid-Infrared (FTIR) spectroscopy
which limited the data to chemical information about functional
groups.
Here we present the preliminary organic geochemical results of solvent
extractable lipids revealed by Electron Ionization Gas-
Chromatography-Mass Spectroscopy from six amber granuales and six living
conifers. These specimens contained a variety of extractables including cyclic
terpenoids and aromatics as well as normal and cyclic alkanes. However,
generalized similarities are observed and further elucidated using reconstructed
ion
chromatograms (RIC). Ions selected such as m/z 83, 109, 123, 191, 217, 231, and
253 are routinely used as lipid biomarkers by organic geochemists. Additionally,
we inventoried and monitored major fragment ions belonging to numerous
unidentified molecules to better understand the extracted components.
In general the extractants are consistant with plant exudates that contain
terpenoids, phenolics, ketones and hydrocarbons.
As expected, most were saturated due to diagenetic alteration.
One exception is the presence of the monoterpene-ketone camphor in the
specimen AMB-7B01. This unaltered, volitale
substance found in gymnosperms is a remarkable case of preservation.
These observations hold promise that biochemosystematics
can help construct clearer understandings in studies of phylogenetic,
paleoclimatic and paleobotanic
processes and relationships.
KEY WORDS: ambers, GC-MS, Triassic, Chinle
biochemosystematics
ANALYTIC PROCEDURES CAN
BENEFIT BIOASSY
