[1] We collected 56 marine gravity cores from the Pacific seafloor offshore Central America which contain a total of 213 volcanic ash beds. Ash-layer correlations between cores and with their parental tephras on land use stratigraphic, lithologic, and compositional criteria. In particular, we make use of our newly built database of bulk-rock, mineral, and glass major and trace element compositions of plinian and similarly widespread tephras erupted since the Pleistocene along the Central American Volcanic Arc. We thus identify the distal ashes of 11 Nicaraguan, 8 El Salvadorian, 6 Guatemalan, and 1 Costa Rican eruptions. Relatively uniform pelagic sedimentation rates allow us to determine ages of 10 previously undated tephras by their relative position between ash layers of known age. Linking the marine and terrestrial records yields a tephrostratigraphic framework for the Central American volcanic arc from Costa Rica to Guatemala. This is a useful tool and prerequisite to understand the evolution of volcanism at a whole-arc scale.

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[1] Sediment gravity cores collected from the Pacific seafloor offshore Central America contain numerous distal ash layers from plinian-type eruptions at the Central American Volcanic Arc dating back to more than 200 ka. In part 1 of this contribution we have correlated many of those ash layers between cores and with 26 tephras on land. The marine ash layers cover areas of up to 10 6 km 2 in the Pacific Ocean and represent a major fraction (60-90%) of the erupted tephra volumes because the Pacific coast lies within a few tens of kilometers downwind from the volcanic arc. Combining our own mapping efforts on land and published mapping results with our marine data yields erupted volumes of all major tephras along the arc that range from $1 to 420 km 3 . Recalculated to erupted magma mass, the widespread tephras account for 65% of the total magma output at the arc. Complementing our tephra data with published volumes of the arc volcanic edifices and volcano ages, we calculate the long-term average magma eruption rates for each volcano. Moreover, we use incompatible element variations to calculate the cumulate masses that were fractionated during variable degrees of differentiation. This yields a minimum estimate of long-term average magma production rate at each volcano, because intrusives without surface expression and losses by erosion are not accounted for. Peak magma production rates increase from Costa Rica to Guatemala, but there is considerable scatter within each region and large differences even between neighboring volcanoes.