Definition of marriage. 1  1a see usage paragraph below : the state of being united as spouses in a consensual and contractual relationship recognized by lawb : the mutual relation of married persons : wedlockc : the institution whereby individuals are joined in a marriage.
The majority of the surface rocks on the North American continent are sedimentary. The mountainous regions of the west and southwest are made of igneous rocks. The Appalachian Mountain region of the eastern U.S. and most of eastern Canada are made of metamorphic rocks.
Igneous rocks are rocks formed from the crystallization of a liquid (molten rock). Igneous rocks may be divided into two categories. Intrusive or plutonic rocks crystallize from magma beneath the earth's surface.gneous Rocks. Of the three principal rock types (igneous, sedimentary, and metamorphic), igneous rocks can be thought of as primary rocks because they crystallize from a liquid. Sedimentary and metamorphic rocks, which we will study later, may be thought of as derivative rocks.