American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.
This paper was prepared for the Improved Oil Recovery Symposium of the Society of Petroleum Engineers of AIME, to be held in Tulsa, Okla., March 22–24, 1976. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made.
Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and with the paper, may be considered for publication in one of the two SPE magazines.
A nuclear logging method to determine the presence of hydrocarbons behind casing regardless of water salinity has been developed.
This log, referred to (is the Carbon Log or Carbon/Oxygen Ratio Log, is commercially available on a limited basis in the United States and Canada..
For most of us in the oil production industry, the Carbon Log principle, including the technique, terminology and method of operation, is new. This paper is written and presented for those who desire an introduction to Carbon Logging.
The intent of this paper is to cover the basic nuclear principles involved, instrument operation and how use is made of the nuclear reactions.
Examples of interpretation techniques for the determination of oil saturation, lithology, salinity and the presence of gas are shown.
The nuclear reactions from which the Carbon Log measurements are obtained are not new. Reactions that occur when certain elements are bombarded with high energy neutrons are well documented.
Fortunately, a number of the elements that are present in the rock matrix and the fluid contained therein do react in some identifiable way to neutron bombardment.
The Carbon Log is made possible due to the fact that Dresser Atlas has a monoenergetic neutron source that can be controled so as to provide a desired amount of neutrons in periodic bursts, i.e. the neutrons produced are of one specific energy level---14.2MEV.
