excess argon

The preliminary conclusion is ( 1) muscovite in high-pressure metamorphic orthogneiss does not contain excess argon and can be the object for 40Ar/ 39Ar dating;

由此得出的初步结论是：①高压变质的正片麻岩中的白云母中不含过剩Ar，这类矿物可以作为~（40）Ar/~（39）Ar同位素测年的对象；

The high pressure muscovite in eclogite contains large amounts of excess argon, that in high pressure paragneiss contains small amounts of excess argon, and that in high pressure orthogneiss contains no excess argon.

初步认定高压白云母中过剩氩的赋存和岩性有关：榴辉岩中的白云母含过剩氩最多，高压副片麻岩中白云母仍含有少量过剩氩，高压正片麻岩中白云母不含过剩氩。