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Mechanical and chemical techniques for separating microfossils from rock, sediment and residue matrix

Published online by Cambridge University Press:  26 July 2017

Anita G. Harris  and
Walter C. Sweet
Anita G. Harris
Affiliation:
U. S. Geological Survey and The Ohio State University
Walter C. Sweet
Affiliation:
U. S. Geological Survey and The Ohio State University
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Extract

Microfossils are most profitably studied as discrete specimens that have been freed from the enclosing rock matrix. Techniques for separating microfossils from matrix and from matrix residues are numerous and relatively simple. Choice of a procedure will depend on the types of microfossils sought, their composition, and the laboratory facilities available. Our own work deals mostly with phosphatic microfossils (conodonts), which are chemically resistant and may be freed from rock matrix and concentrated fairly easily. Calcareous microfossils, such as foraminifers and ostracodes, may be separated and concentrated from relatively unconsolidated sediments rather easily, but freed from some other rock types only with considerable effort (Lethiers and Crasquin-Soleau, 1988), inadequately, or not at all. Many of the laboratoryprocessing techniques for phosphatic, calcareous, and siliceous microfossils are the same. We have not included techniques (e.g., thin-sectioning, preparation of latex replicas, or slabbing) for studying these microfossil groups in rock matrix.

Type
Techniques for Micropaleontology
Information
The Paleontological Society Special Publications , Volume 4: Paleotechniques , 1989 , pp. 70 - 86
Copyright
Copyright © 1989 Paleontological Society 

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