Investigation of chloritization of smectite

Oba, Takanobu*

JNC TJ8400 2003-004, 53 Pages, 2003/03

JNC-TJ8400-2003-004.pdf:2.82MB

The stability of smectite under the bulk composition of high iron content is as follows:(1) and (2). (1)In early burial diagenesis, the chemical variations of chlorite and dioctahedral. smectite in Tertiary formations of Niigata prefecture (2)The experiment of the stability of smectite in iron - rich bulk composition under oxygen fugacity. In the present study, the results are as follows: (1)Samples were taken from the cores and cuttings of exploratory test well of Oguni. The trioctahedral smectite in tertiary formation decreases with a depth. Below 3800m, Si content of chlorite increases with a depth. In the study, corrensite at 2700m depth has higher Si content, as compared to chlorite at 3800m. Mg/(Mg+Fe) ratios of chlorite/smectite interstratified mineral increase with increasing Si content regardless of the depth. (2)Chlorite/smectite interstratified mineral forms at 250C on the composition of the starting material of Mont:Mt=5:5. Chlorite did not crystallize by using of the starting material of Sap:Mt=5:5 at 250C. At 400C, montmorillonite did not decompose on the starting material composition with low iron content. The iron density is very important for the stability of smectite.