ABSTRACT
Pressure buildups taken by fluid level recording prove to be quite usable for formation evaluation in the "Tyler" sands of Central Montana. This method provides low cost information with surprising accuracy. The procedures followed in obtaining the data, and the precautions taken in assuring the validity of the data are discussed in the paper. The data proved sufficiently accurate to perform engineering calculations in two separate "Tyler" fields. The calculations aided in determination of reservoir parameters, and in one field provided justification for additional development drilling. In another field, the data substantiated the limited reservoir, and development drilling plans were cancelled. The buildup curves illustrated well bore damage in some of the wells and subsequent stimulation of two wells resulted in sustained six-fold and nine-fold increases in producing rates of these wells.
This paper illustrates the value of the engineering calculations when applied to carefully gathered field data. The method should have application in other areas with similar producing properties to the "Tyler" sands in Central Montana.
