CHRONOSTRATIGRAPHY OF VOLCANIC EVENTS CORRELATED TO THE DEGASSING RATES OF THE BARVA AND POáS VOLCANOES IN COSTA RICA

Barva and Poás are composite volcanoes, located in North-central Costa Rica, that are among many that occupy the the volcanically active country of Costa Rica. These volcanoes lie in close proximity to one another, making stratigraphic correlations imperative for the origin identification of the overlapping volcanic pulses. The characteristics of the numerous types of pyroclastic deposits and their extensive properties have helped determine the varying volume and percent gas content of previous volcanic events. The application of geophysical and geochemical data to the stratigraphic interpretations of this area is extrapolated to create a descriptive timeline of the intensity and frequency of the volcanic events of these two volcanoes. Further chemical analysis of organic material with known stratigraphic locations reveal the magmatic evolution of Barva and Poás. Evaluation of the magmatic progression of the two volcanoes has provided a basis from which the rate of degassing can be properly deduced.