American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc. 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. Abstract Well logs can provide an analysis of coal which is comparable to core analysis through the use of new interpretation methods which were developed for use in the United States, Canada and Europe. By using well logging methods, two problems encountered in core analysis are reduced. The answers are available in a very short period of time, there are few storage problems. Introduction Log evaluation of coal is not a new concept. One of the early applications of well logs was to delineate coal seams in Europe. However, a more economical, cleaner, and more versatile energy source was found in crude oil, and wireline geophysical techniques were primarily adapted to evaluation of this resource. In the past 10 years, an increased interest in coal led to the development of log evaluation techniques using devices designed for petroleum applications. The first technique that was developed used an Acoustilog and Densilog combination which could be supplemented with neutron and resistivity devices. This system had several limitations most important of which was hole size. Many coal companies take about 2-1/2" diameter cores (open hole diameter is 4") and logging devices are usually larger than this. Drilling the larger holes adds a considerable amount to the cost. A second objection was that there were few oil wells drilled in coal areas which fit this particular combination of logs so very few oil well recordings would be usable in the coal evaluations. In 1974, Dresser Atlas developed a method which utilized two logs, the Induction Electrolog and Densilog which are frequently encountered in the petroleum industry. This method was later modified to accommodate three other combinations of services. The techniques used in the past to evaluate coal seams consisted of coring the seams and doing a laboratory analysis of the core for carbon, ash, and moisture. Two major difficulties are encountered with this method. The first is keeping the core in its original condition so that the analysis of the data reflects the true condition of the coal. The second problem occurs when core recovery is poor or whenever the coal is drilled into before the commencement of coring. Both of these problems can lead to a poor evaluation of the reserves, however, well logs offer a solution to them.