The stress accumulation within the crust, caused by the surface mass redistribution associated with the glaciation-deglaciation cycle during the Quaternary, was numerically evaluated in order to examine the relationship between active Quaternary volcanism and tectonism in island-arc areas and ice age. The vertical gradient of horizontal stress difference in the lithosphere for a meltwater of 130 m in equivalent sea-level reaches a maximum value of 0.8 MPa/km, which is corresponding to the equivalent buoyancy of about 100 kg/m3 for magma-filled cracks, for an earth model with a lithospheric layer of 20-30 km thickness and with a viscosity greater than 1023 Pa s. The changes in stress difference during the stages of deglaciation of 10,000 years amount to 13 MPa for both the top and bottom of the thin lithosphere. Thus, the additional stress difference within the crust may be effective for island-arc areas with thin lithospheric thickness. We, therefore, speculate that the stress accumulation associated with ice age may be an important trigger and/or accelerator on the active Quaternary volcanism and tectonism for the areas along the circum-Pacific.
All Science Journal Classification (ASJC) codes
- Earth-Surface Processes