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).
Additionally, they contain somewhat more gas than do the ultramafic magmas, but not nearly so much as the felsic magmas. Gabbro is the name given to intrusive mafic rocks, whereas basalt is the name given to extrusive mafic rocks. Mafic rocks are produced in a variety of plate tectonic settings (divergent plate boundaries such as mid-ocean ridges, continental rifts such as our own Basin