摘要
Ⅰ. INTRODUCTIONA significant paleoceanographic event happened at the end of Miocene, i. e. the Messinian stage(about 6.2—5 MaBP). This event was first discovered by Lyell(1833). He found an evolutionary gap of organisms between Miocene and Pliocene based on the records from Tertiary sandstone and marlstone. Many evidences, then, were found in Europe, Africa and circum-Pacific region, e. g. buried river channel was found in Walongs Plain, South France. The channel which cuts deeply into the granitic basement is buried
