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胶南造山带曾经历过五期变质作用：早中元古代麻粒岩相变质作用，以出现紫苏辉石为标志，其变质条件为P＝1．35GPa、T＝787．7℃，属中高压相系、区域中高温变质作用；晋宁期榴辉岩相变质作用，以发育榴辉岩为标志，其变质条件P≥2．8GPa、T＝601～1375℃，属超高压变质作用，榴辉岩围岩的变质条件为P＝1．1～1．6GPa、T＝560～650℃；晋宁一震旦期的角闪岩相变质作用是胶南造山带最重要的一次热动力事件，其形成条件早期为P＝0．311～0．314GPa、T＝564．5～603．3℃，中期为P＝0．25～0．644GPa、T≤700℃，晚期为P＝0.545～0．644GPa、T＝600．7～670．8℃，角闪岩相变质作用的P—T演化趋势线呈顺时针方向的半环状，这种P—T趋势与该区的岩浆活动有关；加里东期的中高压绿片岩相变质作用，以广泛分布的3T型多硅白云母为标志，其形成条件为P＝0．70～0．85GPa、T＝450～510℃，属高温低压变质作用；印支期的低绿片岩相变质作用是区内最晚期的低温动力变质作用，呈带状产出，与韧性或脆韧性剪切带相伴分布，其形成温度为350～447℃。
The Jiaonan orogenic belt experienced five stages of metamorphism: Early Mesoproterozoic granulite facies metamorphism, with peridotite as a symbol, the metamorphic conditions of P = 1.35GPa, T = 787.7 ℃, is in the High temperature facies metamorphism and high temperature metamorphism in the region. The eclogitic facies metamorphism of Jinning period is characterized by the development of eclogite. Its metamorphic condition is P≥2.8GPa and T = 601 ~ 1375 ℃, belonging to the UHP metamorphism, The metamorphic conditions of the eclogite are P = 1.1-1.6GPa and T = 560-650 ℃. Amphibolite facies metamorphism during the Sinian period of Jinning is the most important thermal dynamic event in the Jiaonan orogenic belt , The formation of the early P = 0.311 ~ 0.314GPa, T = 564.5 ~ 603.3 ℃, the interim P = 0.25 ~ 0.644GPa, T ≤ 700 ℃, the late P = 0.545 ~ 0.644GPa and T = 600.7-670.8 ℃. The trend of P-T evolution trend of amphibolite facies metamorphism is a clockwise half-ring. This P-T trend is related to the magmatic activity in this area ; Middle Calandian greenschist facies metamorphism in the Caledonian period was marked by the widespread 3T-type picei muscovite, with the formation conditions of P = 0.70-0.85GPa , T = 450-510 ℃, belonging to the high-temperature and low-pressure metamorphism; the Indosinian greenstone facies metamorphism is the latest low-temperature dynamic metamorphism in the region, showing a banded output, accompanied by the ductile or brittle-ductile shear zone Distribution, the formation temperature of 350 ~ 447 ℃.