Design of a Sampling Plan for Regional Geochemical Surveys

A sampling plan is designed for the purpose of reducing the cost of regional geo-chemical surveys while keeping the thoroughness of the coverage at an acceptable level. The design of the plan is based on statistical methods in conjunction with geological and geochemical considerations. The plan allows several options which depend on the order of priority given to the thoroughness of the survey and to the cost of the coverage. One of these options is the "maximum gain " plan. If this plan is applied to the Upper Mississippi Valley zinc-lead district, for example, we can expect to detect 76 percent of the geochemical targets sought, for a coverage of 50 percent of the district. The application of a similar sampling plan to other mining districts is also suggested