a branch of the Indo-European family of languages, including especially Irish, Scottish Gaelic, Welsh, and Breton, which survive now in Ireland, the Scottish Highlands, Wales, and Brittany. adjective. 2. of the Celts or their languages.
Movement of tectonic plates-higher. Volcanoes, mountains and earthquakes occur at the edges of tectonic plates-their creation depends on the direction the plates are moving.
One suggestion for the cause of plate tectonics is mantle convection which is the result of cooling and heating magma. You could think of mantle convection much in the same waâ¦y lava flows in a lava lamp. Lava rises in a lava lamp because it heats up and becomes less dense.