(under subclass 25) Processes or compositions wherein chemical tracers are utilized for studying or determining the existence, location or flow of materials within or below the earth's crust.
(1) Note. The tracers used in the processes classified in this subclass are typically a chemical composition containing a component that is easily detectable and not normally present in the material under study.
SEE OR SEARCH THIS CLASS, SUBCLASS:
56, for chemical tracer compositions, per se.
SEE OR SEARCH CLASS
250, Radiant Energy,
253+, for processes of geological testing or irradiation including the use of a radioactive tracer in a well and subclass 301 for a process of determination of oil presence contamination or concentration and subclasses 302+ for methods of using tracer which emit radiant energy.
