pericline twin

The type of twinning developedin plagioclase is related to deformation temperature,pericline twin is dominant atdeformation temperature higher than 600℃,albite twin is prevailing at lowertemperature.

研究表明：变形时的温度条件是影响变形双晶类型的主要因素，高温变形条件下趋向于形成肖钠双晶。

During the deformation of plagioclase two types of deformation twin-ning,albite twinning and pericline,twinning,are produced.

在所统计的９个样品内，有６个样品的钠长石双晶几率高于肖钠双晶，其余３个样品的肖钠双晶几率高于钠长石双晶。