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冀西北麻粒岩是我国北方麻粒岩带的重要组成部分，其年龄对探讨我国地壳早期演化历史具有重要价值。本文报道了采自赤城伙房村和崇礼上新营变质岩样品的地球化学特征和Ｓｍ－Ｎｄ同位素年龄。赤城伙房村变质岩年龄为２５１３±５５（２σ）Ｍａ，ＩＮｄ＝０．５０９４４±５（２σ），εＮｄ（ｔ）＝＋１．２±０．５；崇礼上新营变质岩年龄为２６６７±９０（２σ）Ｍａ，ＩＮｄ＝０．５０９３０±８（２σ），εＮｄ（ｔ）＝＋２．４±０．７。冀西北变质岩可能存在两个系列，其原岩分别形成于２９００～２８００Ｍａ和２７００～２６００Ｍａ。该区最早地壳可能形成于２９３２±８４（σ）Ｍａ
The granulite in Northwest Hebei is an important part of the granulite belt in the north of China. Its age is of great value to the exploration of the early crustal evolution history in China. This paper reports the geochemical characteristics and Sm-Nd isotopic ages of the samples collected from the Kitan village and Chichen Xinying metamorphic rocks in Chicheng. The metamorphic rocks in Kitakatamina village are 2513 ± 55 (2σ) Ma, INd = 0.50944 ± 5 (2σ) and εNd (t) = + 1.2 ± 0.5. The age of Chonglin Xinying metamorphic rock is 2667 ± 90 (2σ) Ma, INd = 0.50930 ± 8 (2σ), εNd (t) = + 2.4 ± 0.7. There may be two series of metamorphic rocks in the northwestern Hebei, with the original rocks formed at 2900 ~ 2800Ma and 2700 ~ 2600Ma, respectively. The earliest crust in this area may be formed at 2932 ± 84 (σ) Ma