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根据多道地震资料、深海钻探计划(DSDP)和大洋钻井计划(ODP)的钻井资料描绘的挪威陆缘的一个特有构造是一个由层状喷发玄武岩组成的大型隆起,该隆起呈楔形,并沿整个边缘向海倾斜。它们的成因模式,把它们说成是具有看上覆于变薄陆壳的火山岩的晚期陆内裂谷作用的产物;或是在挪威—格陵兰海底扩张的头几百万年间形成的洋壳的一个组成部分。仅仅对挪威边缘进行研究尚不可能明确鉴别所提出的这两种模式,故又采用双船多道地震探测,对格陵兰东缘的配对部位进行了调查研究。我们发现不汉楔形体出现在格陵兰东缘,而且,其沿走向变化的细节在两个边缘也有反映。此外,我们还发现了它们与最老的磁条带型式的空间关系。在此边缘北部的楔形体比较小,它们几乎出现于磁条带#24的整个朝陆部位。向南,我们发现楔形体变宽,并侵占到磁条带#24型式内,然后发展成为两个分开的楔形体,它们的向海部伤与磁条帝#23—致。两个边缘上的磁条带#32和#24虽与楔形体有联系,但己经遭到歪曲。我们认为这些资料有力地证实了这些楔形体与初生板块边界的构造关系。从世界各地许多大陆边缘对它们的观测表明,丰富的火山相通常可能与离散板块边界的开始有关,我们认为导致过量火山作用的机理很可能是 Mutter 和 Buck(1986)等新近提出的“对流部分熔融”。
A unique feature of the Norwegian continental margin, based on multi-channel seismic data, drilling data from Deepwater Drilling Program (DSDP) and Ocean Drilling Program (ODP), is a large uplift consisting of bedded eruptive basalts that are wedge-shaped The entire edge of the sea tilt. Their mode of genesis is described as the product of a late intra-continental rift that sees volcanic rocks over thinning continental crusts, or the oceanic crust formed during the first millions of years of expansion of the Norwegian-Greenland seabed One part. It is not possible to clearly identify the proposed two models just by studying the edge of Norway. Therefore, the double-hull multi-channel seismic exploration is used to investigate the matching parts of the eastern edge of Greenland. We found that the non-Han wedge appeared on the eastern edge of Greenland and that the details of its variation along the strike were also reflected on both fringes. In addition, we also found the spatial relationship between them and the oldest type of magnetic stripe. The wedges in the northern part of this edge are relatively small, and appear almost throughout the direction of landward of magnetic stripe # 24. Towards the south, we find the wedge widening and encroaching into the magnetic stripe # 24 pattern, then developing into two separate wedges, their sea wounds and magnetic stripe # 23. The magnetic stripes # 32 and # 24 on both edges are associated with wedges but have been distorted. We think these data strongly support the structural relationship between these wedges and the boundaries of the primary plate. Their observations from many continental margins around the world indicate that abundance of volcanic facies may generally be associated with the onset of discrete plate boundaries and we believe that the mechanism leading to excessive volcanism is likely to be the recently proposed convection component of Mutter and Buck (1986) Melt. "