Environmental Engineering Reference
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FIGURE 7
Trace fossils and trace-fossil suites attributable to the continental ichnofacies.
(A) Sandstone bedding plane containing
Scoyenia
(
Sc
) of the
Scoyenia
Ichnofacies. (B) Vertical
section through
Naktodemasis
of the
Scoyenia
Ichnofacies. Scale is 3 cm long. NB: Recent ichno-
taxonomic work suggests that structures identified as
Naktodemasis
in this chapter are better
regarded as
Taenidium bowni
(e.g.,
Krapovickas et al., 2009
). (C) Bedding plane with
Mermia
of
the
Mermia
Ichnofacies. (D) Sandstone with
Coprinisphaera ecuadoriensis
of the
Coprinisphaera
Ichnofacies (photo courtesy of Luis Buatois).
In the Seilacherian framework, ichnofacies are
not
recurring trace-fossil suites,
nor are they ichnocoenoses (
Bromley et al., 2007; MacEachern et al., 2007a, 2010;
Pemberton et al., 1992
). Rather, they reside at a hierarchal level above trace-fossil
suites and constitute the
theoretical models
that encompass distinct ethological and
trophic groupings of trace fossils for the purpose of assisting in the paleoenviron-
mental interpretation of the suites. Individual assemblages, ichnocoenoses, or
suites may be
attributable
to an ichnofacies, but the ichnofacies cannot be said
to be equivalent to them (
Bromley et al., 2007; MacEachern et al., 2007a
). For
the purpose of facies analysis, trace fossils are regardedmore as biogenic sedimen-
tary structures (akin to physical sedimentary structures in lithofacies) than as
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