"Intrusive rock is formed when magma penetrates existing rock, crystallizes, and solidifies underground to form intrusions, for example plutons, batholiths, dikes, sills, laccoliths, and volcanic necks. ...
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Some geologists use the term plutonic rock synonymously with intrusive rock but other geologists subdivide intrusive rock, by crystal size, into coarse-grained plutonic rock (typically formed deeper in the Earth´s crust in batholiths and other plutons) and medium-grained subvolcanic or hypabyssal rock (typically formed higher in the crust in dikes and sills)." - (en.wikipedia.org 02.03.2020)
