Age, source, and distribution of Holocene tephra in the southern Kurile Islands: Evaluation of Holocene eruptive activities in the southern Kurile arc

作者：Razzhigaeva, Nadezhda G.; Matsumoto, Akiko; Nakagawa, Mitsuhiro

来源：Quaternary International, 2016, 397: 63-78.

DOI：10.1016/j.quaint.2015.07.070

• Tephrostratigraphy
• Southern Kurile Islands
• Hokkaido
• Holocene eruptive activity
• Glass chemistry

We identified 32 distinct layers of Holocene tephra in the southern Kurile Islands on the basis of petrological features and C-14 ages of soils beneath or above the tephra layers. Three layers were derived from the volcanoes of Kunashir Island: one from Mendeleev volcano (ca. 2.6 cal ka) and two from Tyatya volcano (1420 cal. BP and AD 1973). Fourteen widely distributed silicic tephra layers were derived from four volcanoes in Hokkaido: Mashu, Rausudake, Tarumai, and Hokkaido-Komagatake. A widespread tephra was derived from Baitoushan volcano, between China and North Korea. Fourteen tephra layers have unknown source volcanoes: 1 silicic medium-K ash, 2 silicic low-K ash, and 11 scoria/pumice ash layers. Except for the medium-K ash, these tephra are presumed to be derived from the volcanoes in the Kurile Islands. It has been known that caldera-forming eruptions occurred at Mashu (Hokkaido) and Lvinaya Past (Iturup) volcanoes in the early Holocene (ca. 12-8 ka). However, we did not find any tephra from Lvinaya Past volcano. Our results provide evidence of the temporal and spatial evolution of eruptive activity in the southern Kurile arc. We conclude that the level of the eruptive activity in the southern Kurile Islands (especially Kunashir Island) has been lower than that in eastern Hokkaido since 8 ka. The islands produced mainly vulcanian and strombolian eruptions of mafic magma, whereas eastern Hokkaido produced plinian eruptions of silicic magma repeated at intervals of 1000-2000 years.

• 出版日期2016-3-18