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embraced the scheme, because it offers little of sedimentological significance,
since it addresses situations with no appreciable vertical (stratigraphic) mixing.
A third controversial topic in the realm of ichnofabric involves differing
ideas of the role of biogenic activity in influencing, or even controlling, early
diagenetic processes in the sediment. Virtually, all ichnologists agree that dia-
genetic features should be shunned in ichnotaxonomic and paleoethological
studies of trace fossils. However, sedimentary rocks displaying an ichnofabric
also commonly display a diagenetic fabric, which may have developed along a
pathway outlined by burrows and other ichnological attributes of the original
sediment. A diagenetically induced ichnofabric may include differential
cementation and/or mineral replacement of burrow walls or burrow-fill sedi-
ment. The geological record is replete with nodular fabrics and mineralized bur-
rows, where the resultant diagenetic fabric reflects and enhances the
ichnofabric, particularly in carbonate sediments ( Bromley, 1967; Bromley
and Ekdale, 1986b; Kennedy and Garrison, 1975; Knaust et al., 2012 ). Caution
is warranted, of course, because some types of non-biogenic features resulting
from diagenetic processes (including compaction and dissolution phenomena)
may be mistaken for biologically generated ichnofabrics.
4. IMPORTANCE OF ICHNOFABRIC
Ichnofabric, at its center, pertains to the potential interpretations one can make
from the mode and style of preservation of trace fossils and other evidence of
bioturbation and bioerosion. In recent years, ichnofabric has been compared and
contrasted with ichnofacies and ichnocoenoses by some workers, sometimes
confusing their definitions and applications. In a way, they (ichnofabrics, ich-
nofacies, and ichnocoenoses) simply are three different approaches to interpret-
ing the same thing. In a strict sense, ichnofacies analysis is centered on
interpreting physical aspects of the depositional environment (e.g., bathymetry,
salinity, oxygenation, substrate character, etc.) based on the association of the
identifiable trace fossils that occur. Some workers apply the ichnofacies concept
more broadly to include ichnological aspects that go beyond the recognition of
trace fossils ( MacEachern et al., 2007; Pemberton et al., 2004 ), but the principal
objective of ichnofacies analysis nevertheless has a distinctly paleoenviron-
mental focus, whereas the scope of ichnofabric analysis is much broader
( Buatois and MĀ“ngano, 2011; Gerard and Bromley, 2008; Gingras et al.,
2011; McIlroy, 2007, 2008 ).
In a strict sense, ichnocoenosis studies are centered on interpreting paleo-
ecological aspects of the benthic community based on the wide range of results
of their burrowing and bioeroding activities. The ichnoguild approach, cham-
pioned by Bromley (1996) , contributes significantly to such studies. Ichnoguild
offers a combined view of the microhabitat within the substrate, especially in
terms of infaunal tiering ( Bromley and Ekdale, 1986a ) or ecological stratifica-
tion ( Seilacher, 1978 ), and the ecological niche (i.e., functional role within the
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