On the specimen preparation techniques for examining geological specimens using scanning electron microscopy

Abstract EN

In the scope of a research project the possibilities of Scanning Electron Micros- cope (SEM), formerly used in biology and medicine, have been tested, in order to evaluate the structural features of mud cakes from water based drilling fluids.

Over fifty specimens were studied using SEM in air-dried, substitution-dried, freeze-dried and in frozen-hydrated stages.

The filter cakes were formed statically on filter paper and dynamically on reservoir sandstone.

It has been observed that the structures of the air-dried and the substitution-dried specimen were destroyed.

However, the original structure of the freeze-dried and frozen-hydrated specimen were preserved.

In general, geologists have been slower than biologists in using SEM and in applying freez- ing and freeze-drying techniques.

However, the number of geologists using SEM as a supple- ment to the conventional geological microscopic methods has increased rapidly over the past decade.

This paper presents an overview of freezing and frecze-drving techniques to the SEM exami- nation of drilling fluids and reservoir sandstones.