New Analyses of Lake Sediments from Eastern Labrador: Implications for Exploration

Reanalysis of 6636 organic-rich lake-sediment samples, for 65 elements, from the Geological Survey of Canada's archive, collected from a large region of northern and northeastern Labrador, has improved the definition of five previously known anomalous signatures. It has also enabled the identification of two additional anomalies of unknown or partly known provenance. . In most cases, the signatures are defined by multiple elements. Profiling, filtering, and smoothing techniques were applied to the data. Some known mineral occurrences, including the Voisey's Bay Ni-Cu-Co deposit, and rock types of distinctive composition such as the Florence Lake greenstone belt have characteristic dispersion patterns of varying strength. In contrast, the response to other well-documented mineralized occurrences, such as those around the U occurrences at Moran Lake, are weak to absent. Potential bedrock sources for other strong anomalies have not yet been identified. It is important to take into account that the anomalous results occur in, or are derived from, glacial sediments formed from one or more complex erosion and deposition events that the region has undergone. The new geochemical analyses have added value to archived lake-sediment samples by improved detection limits, and include elements not analyzed previously, such as suites of rare-earth and other critical elements such as Bi, Ge, In, Pd, Pt, Sn and Te. They should find application in future exploration programs, as demand for these commodities continues.