The Canadian Shield is made up of the oldest rocks on earth. And during its four billion year history it has had some guests from other worlds.

Fiery meteorites from space have pockmarked the Shield’s surface but have also brought some unexpected gifts. 1.8 billion years ago, one of them struck near Sudbury, Ontario forming the Sudbury Basin, a deep hole that can be seen from space.

When the meteorite slammed into the earth the impact was many times more powerful than all our nuclear weapons put together. It punched a hole in the earth’s crust, allowing the mantle below to well up and fill the basin with a thick sheet of melted rock. A subsequent shock wave shattered the surrounding rocks, riddling them with fissures and faults that filled up with precious minerals from the melted rock below.

Today, the Sudbury Basin produces hundreds of tonnes of nickel and copper every year and has the biggest concentration of mines in the world.


  • The Sudbury Basin is the second largest known impact crater on Earth - 62 kilometres long, 30 kilometres wide and 15 kilometres deep.
  • The wealth of minerals at the Sudbury Basin was discovered by accident when railway engineers were constructing the Canadian Pacific Railway in 1885.

  • The Great Lakes
    Discover the roots of a long vanished mountain range, explore the remains of an inland tropical sea and trace the story of a dramatic flood
  • The Rockies
    An ever-changing landmass, geologists are learning how the Rockies were formed and discovering what they will become.
  • The Canadian Shield
    The largest - and one of the oldest - expanses of ancient rock on the planet has riches of gold and diamonds under it's crust.
  • The Appalachians
    These fabled mountains contain a geologic puzzle, a rich legacy, and the scarcely known threat of earthquakes.
  • The Atlantic Coast
    The dramatic story of volcanic outpourings, massive rifting of continents and the bursting forth of a new ocean - the Atlantic.

A five-part series that chronicles the incredible—and surprising—history of Canada's landscape in HD.

Canada Rocks Read an excerpt from Canada Rocks, a new book by the scientific advisor to Geologic Journey, Nick Eyles.

Watch video interviews with some of the scientists featured in Geologic Journey (produced in conjunction with National Sciences and Engineering Research Council of Canada).

Order the Geologic Journey DVD for classroom use and download Teacher Resource Materials.
The Nature of Things with David Suzuki
Meteorite: A natural object originating in outer space that survives an impact with the Earth’s surface without being destroyed. Mantle: A 2,900 kilometre thick solid rocky shell comprising approximately 70% of Earth's volume. It is solid and overlies the Earth's iron-rich core, which occupies about 30% of Earth's volume.