MINERALOGY OF MIAROLITIC OPHITES FROM ULTRAMAFITES OF CONCENTRICALLY-ZONAL AND LAYERED INTRUSIONS

摘要

Miarolitic ophiolites (MO) from the layered intrusion consist from lizardite with nonstandard chrysotile whereas MO in the concentrically-zonal massifs consists from clino- and orthochrysotile with povlen-chrysotile and lizardite. This difference is related to evolution of low-temperature postmagmatic fluids. The first one was enriched in Al but poor in alkalis (neutral media), the second one had an opposite tendency (alkali media). Both types of massifs were formed from magma under hypabissal conditions.