Geochemistry of igneous rocks from the central North Atlantic: The Azores and the Mid-Atlantic Ridge
Abstract
A geochemical and petrological study of igneous rocks were carried out in order to investigate the nature of geochemical variations in the region, determine its origin, and investigate the relationship between Mid-Atlantic ridge basalts and lavas from the Azores Islands. Seventy two basalts from the Mid-Atlantic Ridge between 29 degrees N and 60 degrees N were analyzed for Sr-87/Sr-86, K. Rb, Cs, Sr, and Ba. Thirty five island lavas, two submarine basalts from the Terceira Rift, and four mafic and ultramafic coarse grained inclusions in island lavas were analyzed for Sr-87/Sr-86 major elements, first transition series metals, rare earth elements, K, Rb, Cs, Sr, Ba, Hf, Ta, and Th. A petrographic study and reconnaissance electron microprobe study of mineral phases in island lavas and inclusions were also carried out.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- November 1977
- Bibcode:
- 1977PhDT........43W
- Keywords:
-
- Atlantic Ocean;
- Azores;
- Geochemistry;
- Igneous Rocks;
- Chemical Analysis;
- Lava;
- Minerals;
- Petrography;
- Geophysics