<Original>Internal Structures of Pillow Lobes of Cenozoic and Mesozoic Pillow Lavas in and around Hokkaido

概要

論文の詳細を見る
The internal strcutures of pillow lobes, such as vesicles and joints, have been studied through statistical analyses, comparing the Neogene pillow lavas from Southwest Hokkaido and the Kaiyo Seamount, northern Japan Sea, and the Mesozoic pillow lavas from the Nemuro Peninsula. The internal structure of a pillow lobe is characterized by vesicularity, such as hollows, pipe vesicles and spherical-ellipsoidal vesicles, and contraction cracks including radial, radial-concentric and tortoise-shell joints. Measurements and statistical analyses of the vesicles of the Neogene pillow lobes in Southwest Hokkaido and the Kaiyo Seamuout in the northern Japan Sea, revealed that the water depth where both of the piollow lobes were erupted was nearly the same. Furthermore, the fact that contration joints have developed much more on the upper hemisphere than on the lower hemisphere in the Cretaceous pillow lobes, may be explained by differences in the cooling velocities between the upper and lower hemispheres.
北海道東海大学の論文
1990-03-20