Premium
The crystallisation and differentiation of a layered intrusion of hydrated alkali olivine‐basalt parentage at Rhiw, North Wales
Author(s) -
Cattermole P. J.
Publication year - 1976
Publication title -
geological journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.721
H-Index - 54
eISSN - 1099-1034
pISSN - 0072-1050
DOI - 10.1002/gj.3350110105
Subject(s) - olivine , basalt , trachyte , geology , geochemistry , intrusion , outcrop , hornblende , alkali basalt , alkali metal , magma , fractional crystallization (geology) , mineralogy , volcanic rock , chemistry , volcano , quartz , paleontology , biotite , organic chemistry
Abstract Three outcrops of hornblende‐bearing basic intrusives at Rhiw, S.W. Lleyn, are considered to represent faulted remnants of a single larger intrusion. The layered rock series evolved by fractional crystallisation of hydrated alkali olivine‐basalt magma which was emplaced as a number of distinct pulses. The trend of differentiation is similar to that for the Hawaiian series: alkali olivine basalt‐ hawaiite‐trachyte. Consideration is given to the respective roles of pO 2 and pH 2 O in controlling the course of differentiation.