@article{oai:ir.kagoshima-u.ac.jp:00011304,
 author = {山下, 大輔 and YAMASHITA, Daisuke and 大木, 公彦 and OKI, Kimihiko},
 journal = {鹿児島大学理学部紀要, Reports of the Faculty of Science, Kagoshima University},
 month = {Dec},
 note = {Lacustrine sediment, unconformably overlies the late Pleistocene Kariya Lava and overlain by the
Ata Pyroclastic Flow Deposit is exposed in the wall area of Ata Caldera so called, Ibusuki City. It was
named the Horekizon Formation by authors. This formation characteristically contains a pyroclastic
material and divided into three horizons based on their lithofacies. The presence of lacustrine sediment in
the caldera wall area suggests that caldera area was mountain before collapse of Ata caldera. Thirteen
ground layers are observed in the Ata Pyroclastic Flow Deposit in Horekizon area. Based on the vertical
change of lithofacies of the Ata pyroclastic flow deposit, a plinian eruption, twelve small and medium
pyroclastic flow eruptions, three gigantic pyroclastic flow eruptions and two small pyroclastic flow eruptions are recognized in ascending order. A ground layer in the lower Ata Pyroclastic Flow Deposit contains
boulder reach a maximum diameter of 1.3 meters and a ground layer in the middle Ata Pyroclastic Flow
Deposit contains lithic clasts of granite, mudstone and silicified rocks. The lithic clasts in the ground layers
are presumed to have been derived from the late Pleistocene andesite. The occurrence of the Horekizon
Formation and the Ata Pyroclastic Flow Deposit support the idea that source of the Ata Pyroclastic Flow
Deposit is situated at southward near Horekizon area.},
 pages = {1--18},
 title = {指宿市池田堀切園に分布する堀切園層と阿多火砕流堆積物の腑存状況},
 volume = {45},
 year = {2012}
}