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shallowing, this surface implies an erosional event. The facies jump was inter-
preted to represent a forced regression and the surface was interpreted as a
response to sea-level fall.
6. CONCLUSIONS
Although still lagging behind our knowledge of wave-dominated marine set-
tings, the ichnology of tide-dominated open-marine environments has received
increased attention during the past decade. As a result, an integrated ichno-
logical and sedimentological model that allows the delineation of supratidal,
intertidal (mud, mixed, and sand flats), and shallow subtidal subenvironments
has been proposed. Integration of sedimentological and ichnological datasets
also helps to characterize compound dune fields, sand sheets, sand ridges,
isolated dune patches, and tidal bars. The integration of this information into
a sequence-stratigraphic framework, in turn, allows the distinction of two types
of parasequences. The first type is related to tidal-flat progradation and is
reflected by the replacement of the
Skolithos
Ichnofacies by the
Cruziana
Ichnofacies within fining-upward successions. The second type relates to the
progradation of a sand sheet and is characterized by the transition from the
Sko-
lithos
Ichnofacies to non-bioturbated high-energy sandstones of the sand-sheet
core as represented in coarsening-upward successions. Tidal-flat parasequences
are typically characterized by high-energy flooding surfaces delineated by the
Glossifungites
Ichnofacies.
ACKNOWLEDGMENTS
We thank Dirk Knaust and Richard Bromley for their willingness and patience to include this
chapter as part of their book, Brian Pratt for his valuable feedback on the Gog Group, and
Burghard Flemming for his insightful comments which have considerably improved this
chapter. Financial support for this study was provided by Natural Sciences and Engineering
Research Council (NSERC) Discovery Grants 311727-05/08 and 311726-05/08 awarded to
M´ngano and Buatois, respectively.
REFERENCES
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