Record details

    The Late Miocene Guacimal Pluton in the Cordillera de Tilarán, Costa Rica: its nature, age and petrogenesis
    Alvarado, Guillermo
    Huapaya, Sofia
    Janoušek, Vojtěch
    Košler, Jan
    Mixa, Petr
    Ulloa, Andrés
    Vondrovicová, Lenka
    Žáček, Vladimír
Publication type
    článek v periodiku
Source title - serial
    Journal of Geosciences
    Roč. 56, č. 1
Thesaurus term
    granitic rocks, geochemistry, mineralogy, zircon U-Pb age, Guacimal Pluton, Costa Rica, Central American Volcanic Arc
Abstract (in english)
   The Guacimal Pluton situated in the Cordillera de Tilarán in the NW of Costa Rica forms an oval-shaped body with an exposed surface of 60-70 km2. The pluton intruded into basic volcanic rocks of the Aguacate Group (Miocene-Pliocene) and is surrounded by a aureole of calc-silicate metasomatic rocks. The pluton is mainly formed by monzogranites to granodiorites, which strongly prevail over more basic types. The pluton was emplaced at depth of c. 3 km, crystallized at temperature of c. 760-800 °C under a relatively high oxygen fugacity (1.6-2.1 log units above the NNO buffer) and increased activities of volatiles (H2O, F) upon cooling. The prevailing, felsic rocks of the Guacimal Pluton are high-K calc-alkaline. Laser ablation ICP-MS dating of zircons from two granite samples yielded statistically identical U-Pb ages of 6.3 ? 0.5 and 6.0 ? 0.4 Ma, respectively. The Sr-Nd isotopic compositions are rather primitive (87Sr/86Sr6 = 0.70380-0.70413, e6Nd ~ +7.3 to +7.9).
    Česká geologická služba
Contributor code
    ČGS (RIV)
Source format
Import date
    15. 10. 2014