The International Mineralogical Association's approved amphibole nomenclature has been revised in order to simplify it, make it more consistent with divisions generally at 50%, define prefixes and modifiers more precisely and include new amphibole species discovered and named since 1978, when the previous scheme was approved. The same reference axes form the basis of the new scheme and most names are little changed but compound species names like tremolitic hornblende (now magnesiohornblende) are abolished and also crossite (now glaucophane or ferroglaucophane or magnesioriebeckite or riebeckite), tirodite (now manganocummingtonite) and dannemorite (now manganogrunerite). The 50% rule has been broken only to retain tremolite and actinolite as in the 1978 scheme so the sodic calcic amphibole range has therefore been expanded. Alkali amphiboles are now sodic amphiboles. The use of hyphens is defined. New amphibole names approved since 1978 include nyböite, leakeite, kornite, ungarettiite, sadanagaite and cannilloite. All abandoned names are listed. The formulae and source of the amphibole end member names are listed and procedures outlined to calculate Fe3+ and Fe2+ when not determined by analysis.

The International Mineralogical Association's approved amphibole nomenclature has been revised in order to simplify it, make it more consistent with divisions generally at 50%, define prefixes and modifiers more precisely, and include new species of amphibole discovered and named since 1978, when the previous scheme was approved. The same reference axes form the basis of the new scheme, and most names are little changed, but compound species names like tremolitic hornblende (now magnesiohornblende) are abolished, as are crossite (now glaucophane or ferroglaucophane or magnesioriebeckite or riebeckite), tirodite (now manganocummingtonite) and dannemorite (now manganogrunerite). The 50% rule has been broken only to retain tremolite and actinolite as in the 1978 scheme; the sodic-calcic amphibole range has therefore been expanded. Alkali amphiboles are now sodic amphiboles. The use of hyphens is defined. New amphibole names approved since 1978 include nyböite, leakeite, kornite, ungarettiite, sadanagaite and cannilloite. All abandoned names are listed. The formulae and source of the amphibole end-member names are listed, and procedures outlined to calculate Fe 3+ and Fe 2+ where not determined by analysis.

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The American margins of the Caribbean comprise basins and accreted terranes recording a polyphase tectonic history. Plate kinematic models and reconstructions back to the Jurassic show that Mesozoic separation of the Americas produced passive margins that were overridden diachronously from west to east by allochthonous Caribbean plate-related arc and oceanic complexes. P-T-t and structural data, sedimentary provenance, and basin-subsidence studies constrain this history. Caribbean lithosphere is Pacifi c-derived and was engulfed between the Americas during their westward drift as the Atlantic Ocean opened. This began ca. 120 Ma with development of a west-dipping Benioff zone between Central America and the northern Andes, now marked by the Guatemalan and Cuban sutures in North America and by the northern Colombian and Venezuelan "sutures" of South America, persisting today as the Lesser Antilles subduction zone. Most Caribbean high-pressure metamorphic complexes originated at this subduction zone, which probably formed by arc-polarity reversal at an earlier west-facing Inter-American Arc and was probably caused by westward acceleration of the Americas. The mainly 90 Ma Caribbean basalts were extruded onto preexisting Caribbean crust ~30 m.y. later and are not causally linked to the reversal. The Great Caribbean Arc originated at this trench and evolved up to the present, acquiring the shape of the preexisting ProtoCaribbean Seaway. The uplift and cooling history of arc and forearc terranes, and history of basin opening and subsidence, can be tied to stages of Caribbean plate motion in a coherent, internally consistent regional model that provides the basis for further studies.

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