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Infrared video microscopy for the study of graptolites and other organic-walled fossils

Published online by Cambridge University Press:  20 May 2016

Michael J. Melchin
Affiliation:
Department of Geology, St. Francis Xavier University, P.O Box 5000, Antigonish, Nova Scotia B2G 2W5, Canada
Alan J. Anderson
Affiliation:
Department of Geology, St. Francis Xavier University, P.O Box 5000, Antigonish, Nova Scotia B2G 2W5, Canada

Abstract

Organic-walled fossils, such as graptolites and Chitinozoa, show a high degree of transparency to near infrared radiation relative to visible light. Infrared video microscopy (IVM) provides real-time images of the three-dimensional form and internal structure of many specimens that are opaque to visible light. An infrared video camera can be mounted on a biological or petrographic, transmitted-light microscope, and with the addition of a monitor and video printer, images can be viewed and directly printed. With the use of a digital frame-capture system, the IVM images can be digitally stored for analysis, enhancement and printing. As compared with scanning electron microscopy, which only reveals the external form, IVM shows such features as fusellar growth bands and internal septa of graptolites and the prosome structure of Chitinozoa. This method eliminates the need for chemical clearing of specimens for study in visible light, which damages the surface texture and commonly renders specimens too brittle for further manipulation. Infrared video microscopy is potentially applicable to the study of any organic-walled fossils and to the petrographic study of sedimentary organic matter.

Type
Research Article
Copyright
Copyright © The Paleontological Society 

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