Experimental study on wood silicification in the stream of hot spring water : Estimation of rapidity and mechanism of silicification

The writer have soaked several wood pieces in the hot spring water stream (Tateyama Hot Spring Shin-yu) for 7 years where they had found the naturally silicified fallen wood. Weight percentages of silica in the experimented wood pieces increased from zero to ∼0.72%, ∼2.90%, 10.65%, 26.78% and 38.11%, after time intervals of 1, 2, 4, 5 and 7 years, respectively.Wood pieces were silicified by the precipitation of silica spheres in cell lumina of the wood tissue. Hot spring water and silica spheres passed through vessels and vessel pits, and reached individual cells. These facts may explain the origin and the formation mechanism of some silicified wood pieces in the strata of geological age. The silicified wood might be formed through the same mechanism with that recognized in this study within fairly short period of tens or hundreds of years.