The Continental Shields are typically low-lying, stable, flat regions of the continental plates where rocks which have been fused together during very ancient processes of mountain-building (orogeny) are now eroded to rocky areas of low relief. These areas of the continents are usually rigid, and act as single large units that don't break up with continental drift. The oldest rocks on the earth's surface are found in shields, and date back nearly 4 billion years. For example, some Gneiss found in the Canadian Shield up near the Great Slave Lake in the Northwest Territories seems to date from 3.96 billion years ago. The Kabala gneisses from the West Africa shield are about 3.57 billion years old. Much of the southern peninsula of the Indian subcontinent is made up of the India Peninsular Shield.

1. Jnana R Kayal has a page about the geology of India that mentions the Indian shield.
2. A page from Marianopolis college describes the geography of Canada and shows a map of the Canadian shield.
3. Oldest Rocks from the West African shield.
4. An interesting page about the evolving earth and plate tectonics from the University of Michigan..

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