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冀东青龙地区出露的浅变质岩系主要由角闪黑云变粒岩、变质基性—酸性火山岩、浅粒岩、二云石英片岩等组成，夹变质砾岩和铁英岩。姚家沟附近变质砾岩上下的斜长角闪岩的ＳｍＮｄ等时年龄为（２６９６±１８５）Ｍａ，７个样品的ｔＤＭ为２８９０～２９５５Ｍａ。西汉沟具变余枕状构造的斜长角闪岩的ＳｍＮｄ等时线年龄为（２７９３±６９）Ｍａ，其平均模式年龄为２８８４Ｍａ。两套样品相对集中的模式年龄（２．９Ｇａ）代表这套火山岩从地幔分异出的时间，等时线年龄则代表火山岩系形成的时间。
The light metamorphic rocks exposed in the Qinglong area of eastern Hebei are mainly composed of hornblende biotite granulites, metamorphic base-acidic volcanic rocks, shallow-grained rocks, dolomitic quartz-schists, and metamorphic conglomerates and iron-quartzites. SmNd isochron age of (2696 ± 185) Ma for the upper and lower amphibolites of the metamorphic conglomerate near Yaojiagou and 2890 ~ 2955Ma for 7 samples. The SmNd isochron age of the amphibolite in the West Han ditch with a variable pillow structure is (2793 ± 69) Ma with an average model age of 2884 Ma. The relatively concentrated mode age (2.9Ga) of the two samples represents the time when the volcanic rocks separated from the mantle and the isochron age represents the time of volcanic rock formation.