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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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References

Austin, R. L., (ed.). 1987. Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester, 422 p.Google Scholar
Barrick, J. E. 1987. Conodont biostratigraphy of the Caballos Novaculite (Early Devonian-Early Mississippian), northwestern Marathon Uplift, West Texas, p. 120–135. In Austin, R. L. (ed.), Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester, 422 p. Google Scholar
Dorning, K.J. 1987. Integrated conodont and palynomorph preparation of small samples for biostratigraphical and palaeotemperature analysis, p. 51–52. In Austin, R. L. (ed.), Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester, 422 p. Google Scholar
Dow, V. E. 1965. Magnetic separation of conodonts, p. 263–267. In Kummel, B., and Raup, D. (eds.), Handbook of Paleontological Techniques. W. H. Freeman and Company, San Francisco, 852 p. Google Scholar
Freeman, E. F. 1982. Fossil bone recovery from sediment residues by the “Interfacial Method.” Palaeontology, 25(3):471–484.Google Scholar
Gibson, T. G., and Walker, W. M. 1967. Flotation methods for obtaining Foraminifera from sediment samples. Journal of Paleontology, 41(5):1294–1297.Google Scholar
Hauff, P. L., and Airey, J. 1980. The handling, hazards, and mainentance of heavy liquids in the geologic laboratory. U. S. Geological Survey, Circular 827, 24 p.Google Scholar
Hayashi, S. 1969. Extraction of conodonts through HF method. Fossil Club Bulletin, 2:1–9. [In Japanese] Google Scholar
Krukowski, S. T. 1988. Sodium metatungstate: A new heavy-mineral separation medium for the extraction of conodonts from insoluble residues. Journal of Paleontology, 62(2):314–316.Google Scholar
Lethiers, F., and Crasquin-Soleau, S. 1988. Comment extraire les microfossiles a tests calcitiques des roches calcaires dures. Revue de Micropaleontologie, 31(1):56–61.Google Scholar
Merrill, G. K. 1980. Removal of pyrite from microfossil samples by means of sodium hypochlorite. Journal of Paleontology, 54(3):633–634.Google Scholar
Merrill, G. K. 1985. Interfacial alternatives to the use of dangerous heavy liquids in micropaleontology. Journal of Paleontology, 59(2):479–481.Google Scholar
Merrill, G. K. 1987. Improvements in interfacial methods for conodont separations, p. 55–63. In Austin, R. L. (ed.), Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester, 422 p. Google Scholar
Orchard, M. J. 1987. Conodonts from western Canadian chert: Their nature, distribution and stratigraphic application, p. 94–119. In Austin, R. L. (ed.), Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester, 422 p. Google Scholar
Pessagno, E. A. Jr., and Newport, R. L. 1972. A technique for extracting Radiolaria from radiolarian cherts. Micropaleontology, 18(2):231–234.Google Scholar
Riedmiller, A., Hauff, P.L., and Mathias, R. W. 1984. The dangers and handling of hazardous chemicals in the geologic laboratory. U. S. Geological Survey, Circular 924, 39 p.Google Scholar
Savage, N. M. 1988. The use of sodium polytungstate for conodont separations. Journal of Micropaleontology, 7(1):39–40.Google Scholar
Stone, J. 1987. Review of investigative techniques used in the study of conodonts, p. 17–34. In Austin, R. L. (ed.), Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester, 422 p. Google Scholar