Plume mantle source heterogeneity through time: Insights from the Duarte Complex, Hispaniola, northeastern Caribbean
| Autor: | Fernando Contreras, Thomas Ullrich, M. Joubert, Andrés Pérez-Estaún, Dominique Weis, Javier Escuder-Viruete, Piera Spadea |
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| Rok vydání: | 2007 |
| Předmět: |
Atmospheric Science
Geochemistry Soil Science Oceanic plateau Aquatic Science engineering.material Oceanography Mantle plume Mantle (geology) Geochemistry and Petrology Earth and Planetary Sciences (miscellaneous) Amphibole Earth-Surface Processes Water Science and Technology Hornblende Basalt geography geography.geographical_feature_category Ecology Paleontology Forestry Volcanic rock Igneous rock Geophysics Space and Planetary Science engineering Geology |
| Zdroj: | Journal of Geophysical Research: Solid Earth. 112 |
| ISSN: | 0148-0227 |
| DOI: | 10.1029/2006jb004323 |
| Popis: | [1] Located in the Cordillera Central of Hispaniola, the Duarte Complex offers an opportunity to study an on-land fragment of the Caribbean-Colombian oceanic plateau. Geochemical, Sr-Nd isotope, and 40Ar-39Ar radiometric age data combined with detailed mapping have shown that the Duarte Complex includes two lithostratigraphic units, composed of four geochemical groups of metavolcanic rocks: Group Ia, low-Ti high-Mg basalts, and group Ib, high-Ti picrites and primitive high-Mg basalts, occur interlayered in the lowermost levels of the lower unit; group II, light rare earth element (LREE)-enriched picrites, ferropicrites and high-Mg basalts, forms the main lava sequence of the lower unit; and group III, LREE-enriched Fe-Ti basalts, is present exclusively in the upper unit. Nd isotope and incompatible trace element patterns are diverse in the Duarte Complex metavolcanics and are consistent with mantle sources related to a heterogeneous plume. Mantle melt modeling suggests that an early, extensive melting (10–20%) of shallow mantle resulted in the formation of relatively depleted group I and II magmas, whereas the late, more enriched group III magmas were the product of deeper, low-degree ( 96 Ma). Hence an Early Cretaceous phase of the Caribbean-Colombian oceanic plateau construction is recorded in Hispaniola. |
| Databáze: | OpenAIRE |
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