Igneous rocks of the Indian ocean floor

By: , and 



Four dredge hauls from near the crest and from the eastern flank of the seismically active Mid-Indian Ocean Ridge at 23° to 24°S, at depths of 3700 to 4300 meters, produced only low-potassium tholeiitic basalt similar in chemical and mineralogic composition to basalts characteristic of ridges and rises in the Atlantic and Pacific oceans. A fifth haul, from a depth of 4000 meters on the lower flank of a seamount on the ocean side of the Indonesian Trench, recovered tholeiitic basalt with higher concentrations of K and Ti and slightly lower amounts of Si and Ca than the typical-oceanic tholeiite of the ridge. The last sample is vesicular, suggesting depression of the area since the basalt was emplaced. Many of the rocks dredged are variously decomposed and hydrated, but there is no evidence of important chemical modification toward conversion of the lava flows to spilite during extrusion or solidification.

Publication type Article
Publication Subtype Journal Article
Title Igneous rocks of the Indian ocean floor
Series title Science
DOI 10.1126/science.150.3696.605
Volume 150
Issue 3696
Year Published 1965
Language English
Publisher AAAS
Description 6 p.
First page 605
Last page 610
Google Analytic Metrics Metrics page
Additional publication details