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在北大西洋的深海钻探552A 钻井,分四个时段(晚第四纪,约1百万年前,2.4百万年前和前冰期晚上新世)对火山灰层作了研究。区分出了暗色玄武岩火山物质(玄武岩颗粒,为暗色火山玻璃质碎片或气孔状玄武岩)和浅色火山玻璃(浅色泡壁玻屑或是具残破的或板状结构的硅质玻璃颗粒)。暗色火山物质在整个冰期都有产出,其丰度与冰载岩屑有关。浅色火山物质的产出有两种情况:(1)在岩心1和岩心5的两层中与暗色火山物质及冰载物质混合;(2)在岩心9和岩心10中产于与暖期相当的层系中,它与暗色火山物质以及岩屑均无关。本文提出有两种不同的搬运机制。暗色火山物质及浅色火山物质混合物或是源自冰期冰岛的火山爆发,爆发物散落至海域并混进海冰中,或者直接来自冰岛,它们被冰冻结在延伸入海的冰川中。然而,既无暗色火山物质混入也无岩屑的浅色火山物质被推测是由风搬运至552A 站位的。只有浅色火山物质层才是一种特定事件的标志,因而可以作为一种地层工具。
Volcanic ash beds were studied in deep-sea drilling 552A drilling in the North Atlantic Ocean in four periods (Late Quaternary, about 1 million years ago, 2.4 million years ago, and the Precambrian Pliocene). Dark basaltic volcanic material (basalt particles, dark volcanic vitreous fragments or porogen-like basalts) and light-colored volcanic glass (light-colored bubble glass or broken or plate-shaped siliceous glass particles) are distinguished. Dark volcanic material has been produced throughout the ice age, its abundance and ice-bearing cuttings. There are two cases of light-colored volcanic material output: (1) mixing with dark volcanic material and ice-bearing material in both layers of core 1 and core 5; (2) mixing with dark-colored material in core 9 and core 10 Of the strata, it has nothing to do with dark volcanic material and cuttings. This paper proposes two different handling mechanisms. Dark volcanic material and light volcanic material mixtures or volcanic eruptions originating from Icelandic ice age, the explosives scattered into the sea and mixed into the sea ice, or directly from Iceland, were frozen in the glaciers extending into the sea. However, light volcanic material that has neither dark volcanic material nor cuttings is presumed to be carried by the wind to station 552A. Only the light-colored volcanic material layer is a sign of a particular event, and thus can be used as a formation tool.