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加拉帕戈斯三联点是由科科斯板块、纳斯卡板块和太平洋板块在加拉帕戈斯微板块处汇聚形成的脊-脊-脊型三向连接构造。在科科斯—纳斯卡裂谷的大部分内斜坡以北区域,长约250km、宽约50km的西北—东南向的火山岩裂谷横插在东太平洋海隆的南北向海山上。在过去的4百万年中,东北—西南向的东太平洋海隆为一系列的较小裂谷提供了条件,使得那些小裂谷通常与东太平洋海隆共同形成三联点,而且与正在扩张的科科斯—纳斯卡裂谷有50～100km的距离。本文假设该裂谷的位置是由压力控制的,并且压力与占主导作用的科科斯—纳斯卡裂谷相关,随着与东太平洋海隆的距离增大而增大。我们推测,在科科斯—纳斯卡裂谷的南侧也曾有类似的短暂性的裂谷发生,并且曾有助于旋转的加拉帕戈斯微板块的初期形成(大约是1.5百万年)。
Galapagos triple point by the Cocos plate, the NASCAR plate and the Pacific plate convergence in the Galapagos plate at the formation of ridges - ridges - spine three-way connection structure. The northwestern-southeastern volcanic rift about 250 km long and about 50 km wide in the northern part of the Cros-Nasca rift to the north of the inner ramp is interspersed in the north-south seamount of the eastern Pacific seamounts. Over the past 4 million years, northeast-southwest East Pacific seamounts have provided conditions for a series of smaller rifts so that those small rifts generally form a triple point with the East Pacific Rift, and are associated with the expanding section The Kos-NASCAR rift has a distance of 50 to 100 km. This paper assumes that the location of the rift is pressure-controlled and that the pressure is related to the dominant Cocos-Nasca rift and increases with distance from the East Pacific seamounts. We hypothesize that similar transient transgressions also occurred on the south side of the Cocos-Nasca rift and contributed to the initial formation of a revolving Galapagos microplate (about 1.5 million year).