Four grains of zirkelite and baddeleyite have been found in two plagioclase-rich adcumulates from the Laouni layered intrusion. Microprobe analyses are tabulated and show that the zirkelite is poor in REE; baddeleyite is chemically close to ZrO2 and contains minor Hf (HfO2 0.76-1.15%). These minerals are considered to be crystallization products of pockets of intercumulus liquid. The preferential distribution of zirkelite in anorthosite is explained in terms of expulsion of the intercumulus liquid by sintering or annealing of plagioclase. The crystallization of baddeleyite reflects the sharp increase of Zr in the trapped intercumulus liquid.-R.A.H.
|Number of pages||6|
|Publication status||Published - 1987|