15:35 〜 15:55
[MIS07-01] Use of XRF core scanning for submarine paleoseismology
★招待講演
キーワード：submarine paleoseismology、XRF core scanning、event deposit
Examining geological evidences on the past large earthquakes and tsunamis preserved in the sedimentary successions is essential to reconstruct the long-term history of earthquakes and tsunamis and to deliver observational data that help to reduce uncertainties in seismic hazard assessment for long return periods. To detect earthquake- and tsunami-related event deposits in the sedimentary successions, non-destructive geochemical characterization using µ-XRF core scanning has been often performed. Differences in grain-size and grain-composition between event and non-event deposits affect geochemical compositions. Rapid and non-destructive measurement of µ-XRF core scanning gives us useful information on detection of event deposits even which are difficult to distinguish visually. Geochemical properties of event deposits are also useful for sediment provenance analysis. However, some geochemical proxies are useless to distinguish event and non-event deposits when grain-size and compositions have little difference each other. In the case, combination with the other methodologies such as visual observation, radiography, grain fabric and physical properties are quite important. In this presentation, I will show you some XRF core scanning results of marine cores collected from the Japanese water for the purpose of submarine paleoseismology.