extrusive

What are the reasons that whenever elective and prescribed studies are mixed, an extrusive force regularly appears in the elective?

Deposits formed at shallow depths are related to extrusive rocks and to intrusives near the surface.

Thus, granite is an igneous, intrusive rock; lava is an igneous, extrusive rock.

In the Republics of France and of America the President is of an extrusive kind.

When magmas reach the surface red hot, they form extrusive rocks, such as volcanic rocks.