Quantitative Log Evaluation of the Prairie Evaporite Formation in Saskatchewan
- E.R. Crain (Schlumberger of Canada) | W.B. Anderson (Schlumberger of Canada)
- Document ID
- Petroleum Society of Canada
- Journal of Canadian Petroleum Technology
- Publication Date
- July 1966
- Document Type
- Journal Paper
- 145 - 152
- 1966.Petroleum Society of Canada
- 5.6.2 Core Analysis, 5.6.1 Open hole/cased hole log analysis, 1.6.10 Coring, Fishing, 5.5.2 Core Analysis, 4.3.1 Hydrates, 6.5.4 Naturally Occurring Radioactive Materials
- 0 in the last 30 days
- 207 since 2007
- Show more detail
- View rights & permissions
The problem of solving for the fraction of sylvite, carnallite, halite andinsoluble material in the Prairie Evaporite formation can be performed by asuitable interpretation program based on Gamma Ray, Sonic, Neutron and Caliperlogs. Empirical relations were established between the log values and theformation parameters, the result being a set of four simultaneous equationswhich may be reduced to obtain the desired fractions. Tedious hand calculationcan be eliminated by using computer techniques and automatic log digitizingmachines. Correlation between core and log analysis is good, and the speed andefficiency of the method is valuable in initial formation studies.
The Prairie Evaporite formation has been the object of extensive study inthe past several years (1) (2). It is the richest known potash-bearing bed inthe world, and, as such, it is important that any information gatheredconcerning the zone be accurate and immediately useful.
Electrical and radioactivity well logs have proved to be of value forformation evaluation in the oil industry. A recent paper (3) illustrates theiruse for both qualitative and quantitative interpretation in evaporite sequencesin various parts of North America. This paper will outline the theory andtechnique used for a quantitative interpretation procedure in the potash bedsof the Prairie Evaporite formation in the Province of Saskatchewan. The dataare set up so that they can be handled by an electronic computer. The equationscan also be computed by hand at the well site to supplement the data alreadyavailable. The computer program is presented as an Appendix. An extensivebibliography covering potash geology, development and logging techniques, isincluded.
It is well known that potassium has a radioactive isotope which emits gammaray energy. This isotope comprises a constant fraction of the total amount ofpotassium, so that a Gamma Ray Log, which measures the amount of naturalradioactivity in a formation, frequently gives a measure of the potassiumcontent.
|File Size||545 KB||Number of Pages||8|