Terrain geochemistry is the study of the geochemistry of surficial materials to solve geological and environmental problems. The areal and stratigraphic collection of geochemical data shows the natural geochemical variation between extremes of impoverishment and enrichment of components in surficial materials. In Canada’s glaciated landscape, till is the prime sample type because it is widespread and because it is first-cycle sediment that has a relatively simple history of erosion, transport, and deposition. Trace and minor element data sets exist for till and other media in many areas of the country at reconnaissance and detailed scales of sampling. These data are usable for mineral exploration, for environmental studies, and for studies of Quaternary stratigraphy, mapping, and history.
Drift prospecting is the determination of the provenance of glacial sediments (mainly till) in the search for mineral deposits. This exploration method is based on the premise that debris is usually eroded glacially from a subcropping ore deposit and the debris is deposited in a coherent dispersal train down-ice from the source. Boulder tracing and geochemical analysis of till are the main techniques for mapping dispersal trains.
Recycled till and other glacial sediments, organic detritus, and debris eroded directly from bedrock all contribute to postglacial stream and lake sediments. These sampling media have been used over large regions of the country to characterize the surficial geochemistry of areas where till is unavailable or not economical to collect.
In environmental geology and geomedicine, geochemical data on surficial sediments form the basis for estimating the sensitivity of terrain