Well water trace element reconnaissance, eastern maritime Canada

Abstract

A geochemical survey involving the collection and analysis of about 2000 well water samples from an area of roughly 25,000 km 2 was carried out during the 1975 field season over parts of the Carboniferous basin of eastern Canada. This report describes the results of 1721 regional well sites. Three samples of water were collected from each site and analyzed in four different laboratories for twenty constituents. The distribution and relationships of U, Rn, He F, CH 4, Zn, Cu, Pb, Mn, Fe, pH, suspended matter, depth of well, conductivity and alkalinity are described. The elements U, Rn, He, F, along with conductivity and alkalinity, show systematic regional patterns indicating broad regional belts of element enrichment which are being leached by circulating groundwaters. The close spatial association of these elements over many tens of miles suggests chemical reaction cells or fronts similar to those observed in the uranium mining districts of Colorado and Wyoming in the United States and elsewhere. Their relatively weak character suggests an intermediate cycle in the cyclic enrichment hypothesis believed to be responsible for the formation of epigenetic uranium ore deposits. The heavy elements Zn, Cu, Pb, Mn, and Fe show positive correlation with each other but their spatial distribution is more spotty than that of the uranium elements. Broadly speaking the anomalies of these elements cluster mainly on the southern border of the survey area. Most of the anomalies can be explained in terms of known mineral occurrences The most prominent CH 4 anomaly is located south of Moncton and is believed to be due to the old St. Josephs gas and oil field. Several weaker CH 4 anomalies are probably generated by swamps and peat bogs.