AMS 14C ages determination of the late Holocene Pilas, Mula and Cabeza de Vaca monogenetic volcanoes, Nicaragua

Abstract

Here we present six new 14C ages using the accelerator mass spectrometry (AMS) technique for five samples of paleosol and one charcoal collected from the central part of the Maribios volcanic mountain range, located in the northwestern part of Nicaragua. This region is part of the Nicaraguan active volcanic arc characterized by the occurrence of a historic eruption that gave rise to the “birth” of the Cerro Negro volcano in 1850 CE. The young relief and the new 14C ages obtained in this work reveal that three other Holocene eruptions had recently occurred before the growth of the Cerro Negro volcano in this region. These volcanic events were independently established from an emission vent with simultaneous Strombolian explosions to dominantly effusive eruptions, forming extensive lava flows and associated scoria cones of the Cabeza de Vaca, Mula, and Pilas monogenetic volcanoes. AMS radiocarbon dating from charcoal and paleosols underlying these deposits yielded maximum ages of 1050 ± 30 years BP for Cabeza de Vaca volcano, 860 ± 30 yrs BP for Mula volcano, and 520 ± 15 yrs BP for Pilas volcano. These results of AMS 14C analyses provide reliable age ranges of 990–1025 cal yr AD for Cabeza de Vaca volcano, 1166–1220 cal yrs AD for Mula volcano, and 1410–1424 cal yrs AD for Pilas volcano.