Chalk and Related Deep-Marine Carbonates - Trace Fossils as Indicators of Sedimentary Environments - page 777

oxygenation, bottom-current strength, sedimentation rate, substrate consis-
tency, and early diagenetic regimes that signal paleoceanographic and paleocli-
matic dynamics.
The utility of ichnology in chalk facies analysis and sequence stratigraphy
has obvious implications for the petroleum industry. However, ichnological
investigations may have more direct impacts on petroleum exploration and pro-
duction. As gauges of benthic paleo-oxygenation, trace fossils can help assess
hydrocarbon-source potential. As indicators of diagenetic regimes or deposi-
tional processes, such as remobilization of chalks, that govern porosity and per-
meability, they can help assess the reservoir qualities of chalks and associated
carbonates.
The ichnological attributes of chalks, particularly those characterized by the
Zoophycos , Cruziana , Glossifungites , and Trypanites ichnofacies, seemingly
are well studied. Arguably, there is a greater need for additional systematic stud-
ies to further document and interpret trace-fossil assemblages preserved in
allochthonous chalk facies. These include deep-sea calciturbidites as well as
other gravity-flow deposits formed in shallow epeiric basins.
ACKNOWLEDGMENTS
The author's research on chalk and related deposits was supported by the U.S. National Sci-
ence Foundation, the American Chemical Society—Petroleum Research Fund, and Auburn
University.
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