Abstract We estimated the eruption age of Kannabe volcano, located in southwestern Japan. Although the eruption age had been estimated using tephrochronology and K-Ar dating, the precision of its age determination left some room for improvement. The latest eruption age of Kannabe volcano is well constrained by wide spread tephras to ca. 7.2–30 ka. We applied paleomagnetic dating to a basaltic lava and optically stimulated luminescence (OSL) dating to a soil layer, which are associated with the Kannabe volcano. The soil layer above the Kannabe scoria was newly dated to be 21 ± 6 ka, as inferred from OSL dating. We also made paleomagnetic investigation to estimate the eruption age of the Kannabe basaltic lava. Paleomagnetic data of 23 rock samples from six locations in the Kannabe basaltic lava showed good mutual agreement. The average of remanent magnetizations yields declination of 0.3° and inclination of 65.9° with 95% confidence limit of 2.7°. This paleomagnetic direction with a relatively steep inclination is thought to be correlated with the paleomagnetic secular variation data of sediments in Lake Biwa at ca. 21.5 ka. Based on that information from multi-dating, we inferred that the Kannabe volcano erupted at ca. 22 ka. This result presents profound scientific implications for the precise age determination of young basaltic lava flow, for which few dating methods exist.

中文翻译：

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使用多重测年的神边火山喷发年龄：对年轻玄武岩熔岩流年龄测定的影响

摘要 我们估算了位于日本西南部的神边火山的喷发年龄。尽管已经使用火山年代学和 K-Ar 测年法估计了喷发年龄，但其年龄确定的精度仍有一些改进空间。Kannabe 火山的最新喷发年龄受到广泛分布的火山灰的限制。7.2-30 ka。我们对玄武岩熔岩应用古地磁测年，对与 Kannabe 火山相关的土壤层应用光激发光 (OSL) 测年。根据 OSL 测年推断，神边火山渣上方的土壤层新测年为 21 ± 6 ka。我们还进行了古地磁调查，以估计神边玄武岩熔岩的喷发年龄。神奈部玄武岩熔岩中六个位置的 23 个岩石样品的古地磁数据显示出良好的相互一致性。剩余磁化的平均值产生 0.3° 的偏角和 65.9° 的倾角，95% 的置信限为 2.7°。这种倾斜度相对较陡的古地磁方向被认为与琵琶湖沉积物的古地磁多年变化数据有关。21.5 卡。根据多次测年获得的信息，我们推断神边火山大约在 2000 年喷发。22 卡。这一结果为精确确定年轻玄武岩熔岩流的年龄提供了深刻的科学意义，为此几乎没有定年方法。根据多次测年的信息，我们推断神边火山大约在 2000 年喷发。22 卡。这一结果对精确确定年轻玄武岩熔岩流的年龄具有深远的科学意义，而目前几乎没有测年方法。根据多次测年的信息，我们推断神边火山大约在 2000 年喷发。22 卡。这一结果对精确确定年轻玄武岩熔岩流的年龄具有深远的科学意义，而目前几乎没有测年方法。