Methodology and Techniques - Trace Fossils as Indicators of Sedimentary Environments - page 242

sand ( Stidham and Mason, 2009 ). Molding and casting of trace fossils by using
plaster or latex is a sufficient technique in both vertebrate ichnology ( Goodwin
and Chaney, 1994 ) and invertebrate ichnology ( Seilacher, 2008 ; Fig. 1 B). It can
be used not only for preserving vertebrate footprints, burrows, or bioerosion
structures from the field but also to prepare duplicates from original specimens
in museums and collections.
Neoichnological studies can be carried out based on plaster, polyester, or
polyurethane resin casts obtained from open burrows, a technique commonly
applied in terrestrial, littoral, and sublittoral substrates ( Atkinson and
Chapman, 1984; Bouma, 1969; Farrow, 1975; Gingras et al., 2002b; Knaust
et al., 2012; Reineck, 1963; Shinn, 1968; Tschinkel, 2003 ). In this way, the mor-
phology, size, and details of burrows (e.g., from crabs, shrimps, fishes, insects,
or others) can be captured in situ for later investigations (including measuring,
weighting, identification of commensalism, etc.; Fig. 1 C). In the future, this
technique will be more refined and remotely operated vehicles may allow
burrow casting in the deep sea as recently demonstrated by Seike et al. (2012) .
2.3 Core Sampling of Surface Sediment
Besides conventional coring of sedimentary rocks, special equipment has been
developed to take samples mainly from marine but also lacustrine and fluvial
surface sediments that are unlithified. Different kinds of core samplers such
as hand-held, gravity, vibra-core, box-core, or piston-core samplers are
employed to force a hollow tube into the substrate and to retrieve a vertical pro-
file of the sediment ( Ekdale et al., 1984; Farrow, 1975 ), nowadays sometimes
under video guidance. The sediment column including its ichnological content
can then be sectioned, X-rayed, or cast before examination ( Fig. 1 D). Sediment
box cores as introduced by Reineck (1963) were subsequently extensively used
for ichnological investigation of shallow-marine to deep-sea deposits
( Dashtgard and Gingras, 2005; Wetzel, 1983 ).
2.4 Imaging and Analysis of Dinosaur, Bird, and Mammal Tracks
Tracks and trackways of dinosaur and other vertebrates have received much
attention during the past decades and a number of different techniques are
applied for their analysis. Lockley (1991) provides an overview of conventional
surveying and mapping techniques of dinosaur tracks, and Breithaupt and
Matthews (2001) present innovative techniques for a three-dimensional docu-
mentation and analysis of track sites. Close-range photogrammetry ( Breithaupt
et al., 2004; Petti et al., 2008 ), anaglyph stereo imaging ( Gatesy et al., 2005 ),
high-resolution LiDAR ( Bates et al., 2008 ), and laser scanning ( Petti et al.,
2008 ) combined with geographic information systems were successfully
applied for three-dimensional collection, documentation and analysis of tracks
and trackways, contours, and site visualization.