Chemical compositions of rocks and minerals from an underwater volcano of the Kuril deep-sea basin

Mineralogy and geochemistry of low-temperature hydrothermal manifestations occurring on the surface of basalts and in their cracks within a submarine volcano in the north-eastern part of the Kuril deep-sea basin have been studied. The following order of isolation of mineral phases has been found out: Fe-rich sulphides (pyrite) - Fe-rich layered silicates (hydromica of celadonite-nontronite type) - amorphous silica (opal) - Fe-oxyhydroxides (goethite) - Mn-oxyhydroxides (vernadite). Sulphide mineralization is of the phenocryst-stockwork type. Finding of pure barite fragments does not exclude presence of hydrothermal exhalations (smokers) on this volcanic structure.

Chemical composition and age of magmatic rocks from the underwater Hokkaido Rise

Geological and geophysical investigations carried out within the Hokkaido Rise showed that intrusives composing outcrops of the crystalline basement on the ocean floor form a continuous series from monzonites and diorite-monzonites to granites with prevalence of granodiorites with stable mineralogical association: biotite - hornblende - K-feldspar. Acidic volcanic rocks are characterized by a similar mineralogical association with almost complete absence of plagioclase-pyroxene species. It seems that the Hokkaido Rise, as well as the marginal oceanic Zenkevich swell as a whole are not primary oceanic structural formations and have undergone a complex and long history of geological development with intense orogenic movements that occurred in Middle Cretaceous and preceded subalkaline basalt outpouring during postorogenic subsidence of the Earth crust.

UM Television Studio shots

First UM TV Show with Hazen Schumacher at Clements Library interviewing Homer Ferguson, October 1950