Late Quaternary Explosive Volcanic Activities of the Mindanao-Molucca Sea Collision Zone in the Western Pacific as Inferred from Marine Tephrostratigraphy in the Celebes Sea

  • Author(s): Yueh-Ping Ku, Chang-Hwa Chen, Sheng-Rong Song, Yoshiyuki Iizuka, and Jason Jiun-San Shen
  • DOI: 10.3319/TAO.2008.07.30.01(TT)
  • Keywords: Tephra, Volcanic activity, Celebes Sea
  • Citation: Ku, Y. P., C. H. Chen, S. R. Song, Y. Iizuka, and J. J. S. Shen, 2009: Late quaternary explosive volcanic activities of the Mindanao-Molucca Sea collision zone in the western pacific as inferred from marine tephrostratigraphy in the Celebes Sea. Terr. Atmos. Ocean. Sci., 20, 587-605, doi: 10.3319/TAO.2008.07.30.01(TT)
Abstract

The giant piston core MD01-2387 taken from the eastern Celebes Sea basin provides a marine tephrostratigraphy with higher solution for inferring explosive volcanism in the area surrounding the basin for the past 350 kyr. The sequence contains 65 tephra layers com posed of volcanic minerals and glassy particles. The compositional characteristics of crystal enriched tephra layers and the 87Sr/86Sr of the glass particles (0.7039 to 0.7042) suggest that these ashes were re leased by the volcanoes in the Mindanao-Molucca Sea collision zone, including the south Philippine Arc system, the Sangehi Arc and the Halmahera Arc. The up ward decrease of tephra layers in this core indicates a declining trend of explosive volcanic activity of this collision zone, particularly, after ca. 180 ka in the late Middle Pleistocene. This record also suggests that the shoshonitic volcanism in Central Mindanao be came extinct at ca. 151 ka, which is much younger than what reported previously by onland investigations.

Read 817 times