Paleo-seismic Event Sediments, Especially Tsunami Deposits in Holocene Coastal Sediments.

Bibliographic Information

Other Title
  • 沖積層中にみられる古地震イベント堆積物,とくに津波堆積物について
  • チュウセキソウ チュウ ニ ミラレル コ ジシン イベント タイセキブツ トクニ ツナミ タイセキブツ ニ ツイテ

Search this article

Abstract

Studies on the sediments induced by paleoseismic events, especially tsunami deposits, are reviewed and examined.<br>Various types of sediments with conspicuous characteristics are produced by paleo-seismic events. The following are typical examples of paleo-seismic events in the Holocene coastal sediments that have been studied: (1) Change in sedimentary environment caused by submergence or emergence; (2) Sedimentary structure change of intruded sandy sediments caused by seismic shaking, and re-concentration of heavy minerals in the sediments; (3) Re-sedimentation of marine and lacustrine deposits by gravity flow deposits such as turbidite and subaquatic landslide sediments; (4) deposition of tsunami deposits.<br>Synchronous and regional characteristics are the most useful ones for the identification of these events. Relatively coarser sediments such as sandy or gravelly layers with grading structure are characteristic of tsunami deposits. The deposits also become finer towards the inland, and a frame-like structure often can be recognized at the top contact with the under lain soft sediments. Microfossils and geochemical substances of marine origin sometimes increase at the horizons of tsunami deposits.

Journal

Citations (4)*help

See more

References(51)*help

See more

Details 詳細情報について

Report a problem

Back to top