続成変化に見られる時間的要素

海成層中の沸石化作用を例として

抄録

Zeolites occur commonly in the Neogene marine sedimentary rocks of Japanese oil fields. The zeolite and albite zones are formed mainly by physical factors during burial diagenesis. At the wells drilled in the oil fields, the zeolite and albite zones are present at the various depth and at the different subsurface temperature, and are oblique to the stratigraphic datums.
Based on consideration of burial and thermal histories in these wells, the transformation temperature of silicic glasses-clinoptilolite-analcime-albite reaction series increases with decrease in the effective heating time of Hood and Castano (1975).
For example, clinoptilolite is transformed into analcime at 62 °C for the effective heating time of 5 Ma, and at 105 °C for 0.5 Ma, approximately. The zeolitization in the marine sediments is affected by the temperature and geological time (e. g. effective heating time).