Glacial dispersal trains*
This chapter describes the main features of dispersal trains and illustrates several in order to show what features they have in common, as well as the variability in those features. The tail of a dispersal train is generally many times longer than the head and is usually the part of the train that is detected first by mineral exploration programs using till geochemistry or boulder tracing. Dispersal trains of distinctive boulders, minerals, trace elements or major elements, and radioactive components may increase the size of mineral exploration targets by several orders of magnitude. The Hopetown train in southern Ontario, was derived from a small zinc occurrence in marble. The drilling revealed a thick and complex Quaternary record with up to four glacial sediment units, each having a different ice movement direction that was assigned to each till after till fabric and striae studies were done in the open pit and around the mine.