par Duchesne, Jean-Clair;Demaiffe, Daniel 
Référence Earth and planetary science letters, 38, 1, page (249-272)
Publication Publié, 1978-02
Référence Earth and planetary science letters, 38, 1, page (249-272)
Publication Publié, 1978-02
Article révisé par les pairs
| Résumé : | Terrestrial massif anorthosites have gained new interest for the understanding of the deep zones of the crust and for the reconstitution of its history in Proterozoic time. The purpose of this paper is to show how trace elements can enlighten two controversial questions in the problem of anorthosites, namely the nature of the parental magma and the process which gives rise to related acidic rocks. Data obtained on rocks and minerals coming from the Rogaland anorthositic province, South Norway, are presented together with those available in the literature. The Sr and Ba in plagioclase and their relationship with Ca and K, K and Rb in rocks and plagioclases, rare earth elements (REE) in cumulate minerals and in various liquids, 87Sr/86Sr initial ratios on rocks and minerals as well as a few data on transition elements and on 18O/16O ratios are discussed in the different sections. Quantitative modelling of the behaviour of trace elements is realized mainly by graphical methods in the Bjerkrem-Sogndal layered lopolith and in the Hidra body, both andesine-type massifs. The major conclusions are as follows: 1. (1) |
