CHLORINE CONTENT IN MAGMATIC MELTS ACCORD ING TO MINERAL INCLUSION DATA

Data on chlorine content are summarised on the base of 363 determinati ons of chlorine and main rockfonning elements obtained from analytical measurements of homogeneous melt inclusions. It was found that the ch lorine contents are sufficiently above previous estimates. Basic and u ltrabasic magmas (SiO2 < 53%) contain 0.132 wt% of Cl (average of 87 d eterminations within 0.00 up to 0.41% range); intermediate magmas (SiO 2 = 53-64%) - 0.224 wt% (average of 59 determinations within 0.00 - 1. 20%); acidic magmas (SiO2 > 64% - 0.258 wt% (average of 217 determinat ions within 0.00 - 1.13%). The average chlorine content of all magmati c types is estimated as 0.226 wt%. Taking into account the abundances of different magmatic types at continents it was estimated as 0.176 wt % for the continental block as a whole, whereas the average chlorine c ontent of continents, continental mal gins and oceanic bottom is corre sponding to 0.142. wt%.