Author's Organization：Institute of Geoscience,University of Tsukuba Institute of Geoscience,University of Tsukuba Institute of Geoscience,University of Tsukuba
Published: April 15, 1989Received: December 28, 1988Available on J-STAGE: April 11, 2008Accepted: February 22, 1989
Advance online publication: -
Revised: -
