NJG48-4-07
1968
On the paragenesis of albitites
48
4
269-280

The existing theories for the paragenesis of the Pre-Cambrian albitites of Kragerö and Bamble in South Norway are discussed, and considered untenable in the light of present field and laboratory evidence. It is proposed that an early ultrabasic crystallate, giving rise to magnesian assemblages on alteration and metamorphism, was at times able to separate out from an abnormally phosphorous- and volatile-rich gabbroic magma. The liquid remaining is considered to fall within a threeliquid field of a system silicate-Fe-oxid?-Ca-phosphate, separating into a soda-silicic phase giving rise to albitites, a phosphorous phase giving rise to apalite veins, and an iron phase giving rise to iron orcs.

0029-196X
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