Universidad de Burgos, Departamento de Física, Escuela Politécnica Superior, Avda. de Cantabria s/n, 09006, Burgos, Spain.
Research Group 'Geodesia', Facultad de Matemáticas, Universidad Complutense de Madrid, Plaza de Ciencias 3, Madrid, 28040, Spain.
Sci Rep. 2018 Jan 8;8(1):42. doi: 10.1038/s41598-017-18813-w.
The 3-D inverse modelling of a magnetic anomaly measured over the NW submarine edifice of the volcanic island of Gran Canaria revealed a large, reversely-magnetized, elongated structure following an ENE-WSW direction, which we interpreted as a sill-like magmatic intrusion emplaced during the submarine growth of this volcanic island, with a volume that could represent up to about 20% of the whole island. The elongated shape of this body suggests the existence of a major crustal fracture in the central part of the Canary Archipelago which would have favoured the rapid ascent and emplacement of magmas during a time span from 0.5 to 1.9 My during a reverse polarity chron of the Earth's magnetic field prior to 16 Ma. The agreement of our results with those of previous gravimetric, seismological and geodynamical studies strongly supports the idea that the genesis of the Canary Islands was conditioned by a strike-slip tectonic framework probably related to Atlas tectonic features in Africa. These results do not contradict the hotspot theory for the origin of the Canary magmatism, but they do introduce the essential role of regional crustal tectonics to explain where and how those magmas both reached the surface and built the volcanic edifices.
对加那利群岛火山岛西北海底火山丘上测量的磁异常进行的三维反演建模，揭示了一个沿东北-西南方向延伸的大型反向磁化拉长结构，我们将其解释为一个席状岩浆侵入体，在该火山岛的海底生长过程中就位，其体积可能代表整个岛屿的 20%左右。该体的拉长形状表明，在 1600 万年前之前的地球磁场反向极性时期，加那利群岛中部可能存在一个主要的地壳断裂，这有利于岩浆的快速上升和就位，时间跨度从 0.5 到 1.9 百万年。我们的结果与先前的重力、地震学和地球动力学研究的结果非常吻合，强烈支持这样一种观点，即加那利群岛的成因受走滑构造框架的控制，这种构造框架可能与非洲的阿特拉斯构造特征有关。这些结果并不反对加那利岩浆作用起源的热点理论，但它们确实引入了区域地壳构造的重要作用，以解释这些岩浆是如何到达地表并建造火山丘的。
