Compositional Variations of Spreading Basalts of the King's Trough (Central Atlantic) and Possible Reasons for Them

摘要

The King's trough is a remarkable tectonic structure in the eastern Central Atlantic (Fig. 1) [1]. It is represented by a chain of deep troughs (5000 m and more) and surrounding ridges with a total length of 450 km and a width up to 80 km. The King's trough is located 700 km to the northeast from the Azor Islands and elongated in the east-southeasterly direction from the eastern slope of the Mid-Atlantic Ridge (MAR) to the Azores—Biscay height. The origin of this mysterious structure has long been subjected to discussions, and the two-stage formation of trough is the most grounded model at present [2].