Geology of Lambton County

Geology is the study of the earth, its history and its life as recorded in the rocks. The geology of Lambton County has been the subject of much study over the past century. The region is one of the most densely industrialized in the country.

The first oil production in Ontario began in Lambton county in 1857, at Oil Springs, about 30 km southeast of Sarnia. Oil and gas continue to be produced from Cambrian to Devonian age rocks. Silurian salt deposits have been mined, and man-made caverns in the salt are used to store hydrocarbons. An understanding of the regional hydrogeological system is integral in dealing with the protection of our environment and natural resources.

A Simplified Overview of the Geological Strata Underlying Lambton County


Formation Thickness (m) Composition
Glacial Till 20- 50 clay – particles are finer than 3 millionths of a metre
Sedimentary Rock 300 – 400 limestone – mainly calcium carbonate, dolomite
Sedimentary Salt 300 – 400 e.g. sodium chloride
Sedimentary Rock 500 – 700 dolomite – alternating layers of calcium and magnesium carbonates
Metamorphic Rock Unknown e.g. granite