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).
Schlieren, lenses and boudinaged bands of amphibolite, metasedimentary, granitoid and rare ultramafic rocks are present. Discordant mafic sheets that truncate early compositional layering in the rocks, but that are folded and locally boudinaged, may represent dykes that predate younger supracrustal rocks. Late Archean supracrustal rocks, consisting of ultramafic, mafic, intermediate and felsic volcanic rocks, siliciclastic rocks and ironstones, comprise the greenstone belts that host much of the gold and base metal endowment of Nunavut.