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.
Sedimentary rocks often form in deltas and rivers because the constant flow of the river drags sediments from the river bed and deposits them in a confined area. Igneous rocks are formed when molten rocks cool. Magma and lava spewing from volcanoes are the two most common source for igneous rocks. Granite, pumice, obsidian and scoria are all examples of igneous rocks. Metamorphic rocks begin as either sedimentary or igneous rocks.