In addition to the physical removal and transport of fossil finds, palaeontological
"collection" also involves the on-site gathering and recording of data. First,
the excavated bones and any associated fossil material are systematically
recorded, mapped, and sketched in situ (as found in its orginal
fossilized context). Observations in the field are recorded with attention to both
accuracy and precision so that the observations made and conclusions drawn
from the orginial investigation can be reproduced by subsequent researchers.
Therefore, careful attention is given to a variety of geological and
environmental variables such as the nature of the sediments bounding
and containing the fossil bones, the association
fossils to one another, and the taxonomic composition of the fossil horizon.
Field documentation is vital in reconstructing both the fossils
taphonomic history, and the
palaeoenvironment in which the animal lived.
Once the process of documentation is complete the task of collecting and transporting
the fossil begins. To minimize the risk of damaging fragile fossil material,
a rigorous systematic approach is applied to the collection of dinosaur bones.
However, just as each web user has a favourite method of doing web research, so too
does each excavation team have a preferred set of collection techniques. Ultimately,
the choice of collection procedures reflects a combination of factors including: the
amount and character of the fossil material, the physical terrain and accessiblity
of the site and the budget, time, and staff constraints of the excavation.
The following is a list of collection procedures as provided by Geologist,
Roger Vaughan (Bristol City Museum):
- Remove the majority of the sediment matrix from the fossil - leaving
enough so that the fossil remains intact. (In the case of soft matrix encased fossils
removal can be accomplished manually. However, fossils encased in hard rock matrix may require mechanized means of removal.)
- Dig down to a level below the fossil horizon. (When digging it is important to
continually provide support (e.g. stacked bricks) for the fossils being
undercut).
- Protect the exposed bone by covering it with wet strips of paper and then
"plaster jacketing" it with layers of pieces of sack cloth dipped in plaster.
- Lower a wooden crate (with an open bottom) over the fossils and then slide
the crate bottom under the fossil (detached from the underlying sediments). For
addtional strength spray insulation foam can be used to fill in the gaps between
crate and plastered specimen.
- Transfer the packed fossil (either by hand, simple machine, or small crane) to its
designated vehicle of transport.