Geochemistry is the study of the chemical composition of earth and its rocks and minerals.

In order to determine the chemical composition of the landscape, the Ontario Geological Survey undertakes sampling programs across the province that target a variety of materials. The samples are analyzed, by a variety of methods, to determine what elements are present and in what abundance. Materials that are frequently sampled for geochemical analysis include:

  • rocks
  • mineral grains
  • lake sediments (mud from the lake bottom)
  • overburden (soils)
  • groundwater and surface water

Ontario Geological Survey

The activities of the Ontario Geological Survey associated with geochemistry are:

  • regional-scale drift, lake sediment and water surveys: surficial geochemistry
  • sampling of bedrock conducted as part of regional and thematic mapping projects: lithogeochemistry
  • groundwater sampling across the province: aqueous geochemistry
  • research on rocks and minerals to address specific questions or issues
  • Geoscience Laboratories Analyses and Services
    • high-quality, full service, inorganic analytical services in geochemistry, mineralogy, and reference materials
    • Laboratory Fees and Services Schedule (PDF) - Outlines the fees and services offered by the Geoscience Laboratories (Geo Labs)
    • For more information about analytical services please contact the Geoscience Laboratories


The results of geochemical analysis, either of rock or overburden samples, are frequently used to assist mineral exploration. The abundance of one or more elements may indicate the presence of nearby mineralization and, thus, provide a target area for follow-up exploration.

Geochemistry is also a key tool in assessing the state of the environment. Geochemical analyses can determine the naturally occurring levels of elements and substances in the ecosystem or ascertain if any non-naturally occurring substances are present.

The health of humans and animals is affected by the geochemical composition of the land on which they live and the water they consume. By having a knowledge of areas where health threats exist, these can be addressed or mitigated.

Geo Labs one-page information sheet