The following is a clarification/correction to the section Preeruptive Magmatic Processes At Pinatubo. The intended calculation was to find the change in
required to reduce
from 165 MPa (i.e., the value at 220 MPa total pressure at H2O saturation) to 120 MPa (i.e., the value at 155 MPa total pressure under H2O-saturated conditions). According to the Moore (1998) solubility model, the answer is a reduction in
from 1.0 to 0.73, not 0.94 as previously published. The implication of this...