12:39 PM - 12:42 PM
[SGL39-P06] An attempt to obtain earthquake-related events from stalactite
3-min talk in an oral session
We got stalactites from Kuzuu district in Tochigi prefecture and stalagmites from Ishigaki Island in Okinawa prefecture. We observed banding texture under microscope, analyzed chemical composition by ICP-MS and EPMA and carried out radioactive carbon dating.
The result shows that Si, Al, Mg and Fe are concentrated on dark bands, which implies emplacement of clay minerals on the surface of the Kuzuu stalactite and Ishigaki stalagmite. The AMS14C dating result displays that carbonate of Kuzuu stalactite grew from 37,000 to 33,000 (14C age). We recognized a growth rate anomaly around the middle of the stalactite. In this presentation we discuss possible environmental factor and tectonic event to form banding textures on Kuzuu stalactite and Ishigaki stalagmite.