Sentence:  Caledonides, where the S-dipping slab beneath the Lough Nafooey arc (Dewey & Ryan 1990; Clift & Ryan 1994) became a N-dipping <WSD>subduction</WSD> zone after the Grampian Orogeny. 
Meaning of the word marked with <WSD> tags:  The process of one tectonic plate moving beneath another and sinking into the mantle at a convergent plate boundary.