-
Date submitted2020-11-20
-
Date accepted2021-03-30
-
Date published2021-06-24
Petrochemical features of tholeiites from the Shaka ridge (South Atlantic)
The article presents original data of chemical composition of tholeiitic basaltoids and andesites, dredged from the Shaka Ridge (South Atlantic) in the course of field research in spring 2016 on the scientific expedition vessel “Akademik Fedorov”. The analytical part of the work on estimating the contents of petrogenic, trace and rare-earth elements was carried out using the classical method (“wet chemistry”), X-ray fluorescence analysis (XRF) and inductively coupled plasma mass spectrometry (ICP-MS). The studied samples demonstrate elevated concentrations of large-ion lithophile elements, or LILE, (Ba, Rb, Pb) and light rare earth elements, or LREE, (La, Ce, Nd, Sm) relative to high field strength elements, or HFSE, (Nb, Ta) and heavy rare earth elements, or HREE, (Dy, Yb, Lu). The specifics of trace element geochemistry suggest a significant contribution of crustal or subduction components to the magmas of the Shaka Ridge. Discrimination diagrams of basaltoids and allied rocks with fields of different geodynamic settings indicate that they were formed in the setting of the mid-ocean ridge basalt (MORB). The reason behind the appearance of subduction and crustal marks in the rocks is possibly associated with assimilation of crustal matter by magmas or lies in their inheritance from the mantle source.
-
Date submitted2010-07-13
-
Date accepted2010-09-25
-
Date published2011-03-21
Hydrogeological typisation of the north part of the Mid-Atlantic ridge
- Authors:
- M. V. Krivitskaya
The deep basite-hyperbasite rocks wich are special features for the north part of the Mid-Atlantic Ridge (MAR) are observed. The hydrogeological structures of the MAR are distinguished.