Methodology and Techniques - Trace Fossils as Indicators of Sedimentary Environments - page 246

FIGURE 3 Part of an acetate peel of a bio- and intraclastic limestone slab from the Middle Triassic
of Weimar, Germany, with a Balanoglossites triadicus burrow system filled with sucrose dolomite.
3.2 Thin Sectioning
The preparation of thin sections for petrographical and microfacies studies is an
old technique (see Miller, 1988 ) with many possible applications also in the field
of ichnology, which can be grouped into the following categories: (1) identifica-
tion of minute trace fossils ( Banerjee et al., 2007; Das and Rao, 1992; Knaust,
1998; Wisshak, 2012 ), (2) determination of microcoprolites based on their inter-
nal structure ( Fl ¨ gel, 2004 ), (3) examination of the internal structure of burrows
and rhizoliths for morphological, behavioral, biostratinomic, and diagenetic inter-
pretations ( Knaust, 2009b; Retallack, 2001 ), (4) enhancement of visibility of
indistinct biogenic structures with low color and/or grain-size contrast ( Ol´riz
and Rodr´guez-Tovar, 2002; Schieber, 2003 ), (5) identification of remains of
the tracemaker ( Fig. 4 ), (6) investigation of the composition and tiering patterns
of ichnofabrics and the related fluid-flow behavior ( Gingras et al., 2004 ), and (7)
quantification of bioturbation via image analysis ( Francus, 2001 ).
Large-scale thin sections up to a postcard format are invaluable for the study
of trace fossils and ichnofabrics in transmitted light and may reveal continuous
structures and greater parts of ichnofabrics. This method has been successfully