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对采自河北省迁西县太平寨ＨＢＴ１麻粒岩中的辉石、角门石、斜长石进行了４０Ａｒ－３９Ａｒ年龄测定，并对上述三种矿物做了４０Ｋ－４０Ａｒ同位素封闭温度计算，进而根据封闭温度与年龄的关系，研究了该区麻粒岩体的冷却抬升历史。分别得到辉石坪年龄为２．１６Ｇａ，封闭温度为６２０℃；角闪石坪年龄为１．９７Ｇａ，封闭温度为５１７℃；斜长石坪年龄为１．６６Ｇａ，封闭温度为２６５℃。从２．５Ｇａ（麻粒岩相变质年龄）到２．１６Ｇａ，岩体抬升速率为１４．１ｍ／Ｍａ，冷却速率为０．３９℃／Ｍａ；从２．１６Ｇａ到１．９７Ｇａ岩体抬升速率为１８．５ｍ／Ｍａ，冷却速率为０．５５℃／Ｍａ，从１．９７Ｇａ至１．６６Ｇａ岩体抬升速率为２９．１ｍ／Ｍａ，冷却速率为０．８１℃／Ｍａ。Ａｒ－Ａｒ法给出的这些同位素证据，反映了冀东太古代麻粒岩体变质作用晚期多阶段冷却抬升的漫长历史。
The 40Ar-39Ar ages of pyroxene, kertenite and plagioclase collected from HBT1 granulite in Taipingzhai, Qianxi County, Hebei Province were measured and the 40K-40Ar isotope closure temperature was calculated for the above three minerals. According to the relationship between closure temperature and age, the history of cooling and uplifting of granulite in this area was studied. The ages of Phaeoh Ping are 2.16 Ga and 620 ◦C, respectively. The amphibole Pingping age is 1.97Ga, the sealing temperature is 517 ℃, the plagioclase level is 1.66Ga, and the closing temperature is 265 ℃. From 2.5Ga (granulite facies metamorphic age) to 2.16Ga, the uplift rate of the rock mass is 14.1m / Ma and the cooling rate is 0.39 ℃ / Ma. From 2.16Ga to 1.97Ga, the uplift rate of the rock mass 18.5m / Ma, the cooling rate is 0.55 ℃ / Ma, the rock uplift rate from 1.97Ga to 1.66Ga is 29.1m / Ma, and the cooling rate is 0.81 ℃ / Ma. These isotopic evidence given by the Ar-Ar method reflect the long history of late multi-stage cooling and uplifting of the Archean granulites in the eastern part of the Jidong.