Dundee's Volcano - Fact or Fiction

About 520 million years ago, the Earth looked completely different. Three tectonic plates collided, to make a new continent, part of which formed a massive mountain range as high as the Himalayas to the north of what we now know as Dundee.

Over millions of years, the mountain range was eroded by rain and extreme weather. Rivers brought sediment down to this region, which settled and formed old red sandstone in deep layers above and below where Dundee is now built.

Volcanoes formed the Ochil and Sidlaw hills. However, not all the molten rock emerged at the surface. Some was squeezed through weaknesses in the sandstone sediments, allowing molten rock to flow sideways to Dundee. The volcanic rock of the Law cooled and solidified between sandstone layers, hundreds of metres below the surface.

2.6 million years ago, the Ice Age came to Scotland. Glaciers advanced and retreated several times. They advanced from west to east. As they passed over the land, they wore it away, removing the softer sandstone faster than the volcanic rock. Valleys were gouged out beneath the layer of ice.

The last glacier retreated about 14,000 years ago leaving the hills and valleys we see today. The volcanic rock of the Law was finally exposed.

Geology Facts

  • The Earth’s land masses are moving slowly all the time
  • Rock is constantly being eroded and reshaped
  • At the time the old red sandstone was being laid down, the continent was near the equator
  • The Law is not a volcano and is not a volcanic plug
  • The volcanic rock of Dundee came from a volcano miles away
  • The sandstone of the Law is older than the volcanic rock
  • The Law was shaped by glaciers not lava
  • Glaciers have removed hundreds of metres of rock from above us to form the landscape we see today.