Active volcanic belts mark the eastern and western margins of the Caribbean plate. The Lesser Antilles on the east form a classic island arc, but Central America on the west is a continental volcanic belt and not particularly arcuate. The Central American volcanic belt is slightly longer than that of the Lesser Antilles, 1,100 km versus 750 km, but Central America has 40 Neogene volcanic centers to only 12 for the Lesser Antilles. Central American volcanoes have produced 16 km3 of volcanic products since 1680, whereas the Antillean volcanoes have produced only 1 km3 in the same time period (Wadge, 1984). The contrast is between one of the most active circum-Pacific volcanic belts and one of the least active. Silicic tephra is the dominant volcanic product in the Lesser Antilles; whereas in Central America, basalts and andesites are more abundant. The southern end of the Antilles volcanic front, near Grenada, has a high proportion of alkaline volcanic rocks. The few alkaline lavas found near the volcanic front in Central America occur in Costa Rica, also near the southern end of the volcanic front. In addition to the real physical differences between the two volcanic belts, published descriptions differ because few volcanologists have worked in both areas.
The interdisciplinary nature of volcanology results in a wide range of research efforts, including detailed studies of fumarole minerals, geophysical measurements of many types, a full range of petrologie and geochemical studies, and various methods of measuring and estimating volcanic gas contents, to list but a few.
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The result of a major international effort involving authors and organizations from 13 countries, this volume summarizes the complex geology and tectonic evolution of the Caribbean plate and its relation to the adjacent North American, South American, Nazca, and Cocos plates. Focuses on regional geology and geophysics, magmatic processes, neotectonic features, geologic hazards, and energy and metallic resources. Contrasting views for the Mesozoic and Cenozoic geological evolution are presented in chapters on plate tectonics and mantle surge tectonics. Chapters on marine geology and geophysics are new syntheses for the entire Caribbean region. Highlights of the volume include extensive bibliographies and new syntheses of stratigraphic-lithologic columnar sections, seismicity, gravity and magnetic anomalies, neotectonic features, resource data, and crustal properties.