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This paper summarizes advances since 1987 in the application of glacial sediment sampling to mineral exploration (drift prospecting) in areas affected by continental or alpine glaciation. In these exploration programs, clastic glacial sediments are tested by geochemical or mineralogical methods to detect dispersal trains of mineral deposit indicators that have been glacially transported from source by mechanical processes. In glaciated terrain the key sampling medium, till, is produced by abrasion, crushing and blending of rock debris and recycled sediment followed by down-ice dispersal ranging from a few metres to many kilometres. As a consequence of the mid-1980s boom in gold exploration, the majority of case studies and regional till geochemical surveys published in the past decade deal with this commodity. Approximately 30% of Canada and virtually all of Fennoscandia have been covered by regional till geochemical surveys that aid mineral exploration and provide baseline data for environmental, agricultural, and landuse planning. The most profound event in drift prospecting in the last decade, however, has been the early-1990s explosion in diamond exploration which has dramatically increased the profile of glacial geology and glacial sediment sampling and stimulated changes in sampling and analytical methods.

Mineral exploration methods ranging from boulder tracing to elemental and indicator mineral methods utilize clastic debris transported from mineralized bedrock sources. An understanding of glacial process and history, combined with sound survey design and interpretation, are essential to successful application of these methods in glacial terrain. In North America and Fennoscandia, mineral exploration and glacial geology advanced concurrently in the latter 20th century, coincident with a shift in exploration to verburdencovered regions. During this time, an understanding of sediment transport history was followed by recognition of the textural and mineralogical tendencies of glacial sediments. Development of logistics such as reverse circulation and rotasonic drilling followed, and in the 1990s, the discovery of diamonds in Canada resulted in much progress in application and awareness of drift prospecting methods. The discipline now centres on intricate indicator mineral and elemental methods based on concepts from glacial geology, mineral deposit geology, and mineral chemistry, in the search for a broad range of commodities.

Following the 1997 Red River flood, a program of research was initiated to determine how large the floods can be, how often large floods have occurred in recent centuries, and whether natural factors may be changing the flood risk. As part of this program, 15 cores were collected from the south basin of Lake Winnipeg. Paleomagnetic profiles were used to select three apparently undisturbed, high-sedimentation rate cores for detailed chemical, physical, and biological analyses, to assess whether Red River floods are recognizable in the lake. A thousand-year paleomagnetic chronology was confirmed and augmented by Cs-137, Pb-210, palynology, radiocarbon dating, and inorganic geochemical relative age markers. While some parameters exhibit multi-century fluctuations, varying excursions, and 20th century shifts, grain-size results show the clearest signal of recurring events. Several layers of enhanced silt, 1-4 cm thick, with 6-15 % more silt than background are present, in several cases correlating core to core. A Red River flood origin for these silt excursions is plausible. The results also provide indications of increased contamination, nutrient influx, and more rapid sedimentation in the 20th century.

Thermoluminescence (TL) analyses of Quaternary nearshore marine sediments from the Hudson Bay Lowland revealed relatively high light emissions and linear growth curves to at least 400 Gy above the natural dose. Initial results indicate that anomalous fading may be circumvented by a preheating at 150 °C for 16 h without substantial thermal draining of stable TL components. Both the total bleach method with unfiltered sunlamp light and the partial bleach method with light blocked below 400 nm resulted in overbleaching and thus overestimates of age. A TL age estimate of 5.3 ± 0.8 ka on the Holocene control sample, similar to the radiocarbon age, was obtained using the partial bleach method with light blocked below 540 nm. This same method yielded an average TL age estimate of 73 ± 10 ka for a Pleistocene unit, which corresponds to the amino-acid-based age estimate of ca. 76 ka. The agreement of the two age estimates is encouraging, since both methods rely on separate assumptions that have not been independently verified.

The Portage la Prairie alluvial fan was constructed by numerous successive paleochannels of the Assiniboine River along the western side of the Lake Agassiz basin as the level of the lake rapidly declined beginning 9500 years ago. The history of the paleochannels during the first several thousand years is not known. Paleochannel morphologies and cross-cutting relations, soil maturity, and radiocarbon dates, however, indicate that by 6000–7000 years ago flow was northward into Lake Manitoba. This direction was maintained until about 3000 years ago, when avulsion redirected the Assiniboine eastward to the Red River near Winnipeg. The morphologies of the paleochannels suggest that channel-forming discharges and sediment loads of the ancestral rivers have not differed significantly from the modern values despite palynological evidence that the climate was warmer and drier during much of the Holocene.