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徐家堡子地区以黑云英云闪长质片麻岩（２．４７Ｇａ）为围岩的上壳岩（＞２．９８Ｇａ）包体中，发育几条近东西走向的韧性变形变质带（２．７Ｇａ）。研究表明，该韧性变形变质带在平面和剖面上均呈舒缓波状，发育糜棱叶理、矿物线理和Ｓ－Ｃ组构。带内的糜棱片麻岩矿物成分复杂且多世代矿物共存。变形前以石榴石、黑云母、斜长石和石英矿物组合为代表，形成温度为５００～５２０℃，压力为０．４ＧＰａ；韧性变形同期以夕线石、石榴石、石墨、黑云母、斜长石和石英矿物组合为代表，形成温度为６３０～７００℃，压力０．５８～０．７２ＧＰａ；变形期后以十字石、石榴石、斜长石和石英矿物组合为代表，形成温度为５８６℃。形成了一条顺时针演化的ｐＴｔ轨迹。这种复杂的糜棱片麻岩是多期变形变质作用叠加的结果。
In the Xujiapuzi area, a series of ductile deformation metamorphic zones near the east and west are developed in the upper crust (> 2.98Ga) enclave of the biotite-type dioritic gneiss (2.47Ga) .7Ga). The results show that the ductile metamorphic zone is soothing wavy in both plane and section, and mylonitial foliation, mineral lineage and S-C structure are developed. Mylonite gneissic minerals within the complex mineral composition and more generations co-exist minerals. Deformation before the garnet, biotite, plagioclase and quartz mineral assemblage represented by the formation of a temperature of 500 ~ 520 ℃, pressure of 0.4GPa; ductile deformation over the same period of sillimanite, garnet, graphite, biotite, oblique length Rock and quartz mineral assemblage, the formation temperature is 630-700 ℃ and the pressure is 0.58-0.72GPa. After the deformation period, the assemblage is represented by the combination of spar, garnet, plagioclase and quartz mineral, the formation temperature is 586 ℃. A clockwise pTt trajectory is formed. This complex mylonitic gneiss is a result of the superimposition of multiple stages of metamorphism and metamorphism.