United States invasion of Panama Reference: Wikipedia The United States Invasion of Panama, code-named Operation Just Cause, was the invasion of Panama by the United States in December 1989. It occurred during the administration of U.S. President George H. W. Bush, and ten years after the TorrijosâCarter Treaties were ratified to transfer control of the Panama Canal from the United States to Panama by January 1, 2000.
Ultramafic (also referred to as ultrabasic rocks, although the terms are not wholly equivalent) are igneous and meta-igneous rocks with a very low silica Mg O, high Fe O, low potassium, and are composed of usually greater than 90% mafic minerals (dark colored, high magnesium and iron content).
Report Abuse. Color and density of igneous rock depend on its mineral composition. Felsic (light-colored and low-density) igneous rocks include large proportions of quartz and feldspar. Mafic (dark and dense) igneous rocks incorporate minerals containing iron and magnesium.Ultramafic igneous rocks contain iron-and magnesium-bearing minerals that can form only under deep subterranean pressures, with relatively little silica. http://home.att.net/~cochrans/ignrok01.h...afic (dark and dense) igneous rocks incorporate minerals containing iron and magnesium. Ultramafic igneous rocks contain iron-and magnesium-bearing minerals that can form only under deep subterranean pressures, with relatively little silica. http://home.att.net/~cochrans/ignrok01.h...