Figure 6From: Mechanism of long-standing Cenozoic basin formation in central Hokkaido: an integrated basin study on an oblique convergent margin Characteristics of the volcanism in central Hokkaido. Top: histogram of radiometric ages (courtesy of JAPEX, the Japan Petroleum Exploration Co. Ltd., using the relevant subsurface data set) obtained from the late Oligocene and early Miocene volcanic/volcaniclastic rocks in the southern part of the Ishikari-Teshio Belt. Bottom: geochemical trends of the Mesozoic Sorachi Group (Niida 1992) and the Oligocene-Miocene volcanic rocks (Takinoue; Okamura et al. 2010) in central Hokkaido.Back to article page