The relationship between andesitic volcanism and seismicity in Indonesia, the Lesser Antilles, and other island arcs

Abstract

The relationship between K, the level of potash content in lavas erupted from an andesite volcano, and h, the depth to the center of the inclined seismic (Benioff) zone beneath the volcano, is extended using new data from Indonesia, the Lesser Antilles, and New Zealand. Coefficients of correlation between K and h of +0.86 (K55) and +0.80 (K60) are obtained by straight-line regression. This is compared with a coefficient between K55 and distance d of the volcano from the trench of only +0.60. The coefficients of correlation of K against hmin, which is the depth to the upper surface of the Benioff zone, are not significantly different from those between K and h.