Geochemistry of hydrothermally altered basaltic rocks from the Rodriguez triple junction in the Indian Ocean

Online Access: Get full text
doi: 10.11456/shigenchishitsu1992.49.15
Author(s): Nakamura, Kentaro; Kato, Yasuhiro; Ishii, Teruaki
Author Affiliation(s): Primary:
Yamaguchi University, Department of Earth Sciences, Japan
University of Tokyo, Japan
Volume Title: Shigen Chishitsu
Source: Shigen Chishitsu, 49(1), p.15-28. Publisher: Shigen Chishitsu Gakkai - Society of Resource Geologists of Japan, Tokyo, Japan. ISSN: 0918-2454 CODEN: KOZCAZ
Note: In Japanese
Summary: Basaltic rocks dredged from near the Rodriguez triple junction are analysed. Fresh basalt is MORB although only Nb is slightly depleted. Altered basalt containing a brown alteration mineral is enriched in K, Rb and U, suggesting low-T seafloor weathering. Chloritized rocks show an enrichment of Mn, Mg, Na, Cu and Zn and a depletion of Ca, K, Co, Rb, Sr and Ba, which may be attributed to an addition of base metals from hydrothermal solutions and to the hydrothermal alteration by virtue of sea-water cycling through oceanic crust. These geochemical features are comparable to those of the pillow basalt zone and the transitional zone toward the sheeted dyke zone in the IPOD/ODP Hole 504B.
Year of Publication: 1999
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
ODP Ocean Drilling Program
Key Words: 02 Geochemistry; 05 Petrology, Igneous and Metamorphic; Alteration; Basaltic composition; Basalts; Chloritization; Crust; DSDP Site 504; Deep Sea Drilling Project; Dikes; East Pacific; Equatorial Pacific; Geochemistry; Hydrothermal alteration; IPOD; Igneous rocks; Indian Ocean; Intrusions; Lava; Low temperature; Metasomatism; Mid-ocean ridge basalts; North Pacific; Northeast Pacific; Ocean Drilling Program; Ocean floors; Oceanic crust; Pacific Ocean; Pillow lava; Rodriguez triple junction; Sea water; Temperature; Volcanic rocks; Weathering
Coordinates: N011335 N011338 W0834348 W0834357
Record ID: 2016021844
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from Mineralogical Abstracts, United Kingdom, Twickenham, United Kingdom