Page 144 - Geochemistry of Oil Field Waters

132 INTERPRETATION OF CHEMICAL ANALYSES

ion fraction usually in multiples of 10. However, when looking at a group of
waters all must be plotted on the same scale.
Many investigators believe that this is the best method of comparing
oilfield water analyses. The method is simple, and nontechnical personnel
can be easily trained to construct the diagrams.

Other methods

Several other water identification diagrams have been developed, primarily
for use with fresh waters, and they will not be discussed here. The Piper
(1953) diagram and the Stiff (1951) diagram were adapted to automatic data
processing by Morgan et al. (1966), and Morgan and McNellis (1969). The
Piper (1953) diagram uses a multiple trilinear plot to depict the water analy-
sis, and this quaternary diagram shows the chemical composition of the
water in terms of cations and anions. Angino and Morgan (1966) applied the
automated Stiff and Piper diagrams to some oilfield brines and obtained
good results.

References

Angino, E.E. and Morgan, C.O., 1966. Application of pattern analysis to the classification
of oilfield brines. Kans. State Geol. Sum., Comput. Contrib., No.7, pp.53-56.
Morgan, C.O. and McNellis, J.M., 1969. Stiff diagrams of water-quality data programmed
for the digital computer. Kuns. State Geol. Sum., Spec. Distrib. Publ., No.43, 27 pp.
Morgan, C.O., Dingman, R.J. and McNellis, J.M., 1966. Digital computer methods for
water-quality data. Ground Water, 4:35-42.
Piper, A.M., 1953. A graphic procedure in the geochemical interpretation of water analy-
ses. US. Geol. Surv. Ground Water Note, No.12, 14 pp.
Reistle, C.E., 1927. Identification of oilfield waters by chemical analysis. U.S. Bur. Min.
Tech. Paper, No.404, 25 pp.
Stiff, H.A., 1951. The interpretation of chemical water analysis by means of patterns. J.
Pet. Technol., 3:15-17.
Tickell, F.G., 1921. A method for graphical interpretation of water analysis. Calif. State
Oil Gas Superv., 6:5-11.