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中朝克拉通北部早前寒武纪变质作用演化及其ＰＴｔ轨迹主要有三类样式：第一类以内蒙古集宁—怀安太古宙高级区为代表，ＰＴｔ轨迹表现为顺时针形式，峰期温压高达８００℃～８５０℃，０．９０ＧＰａ～１．００ＧＰａ，峰期后为大幅度等热减压，反映了板块碰撞造山带的陆壳成倍构造增厚和后期拉张减薄机制；第二类以冀东—辽西太古宙高级区为代表，ＰＴｔ为逆时针形式，早期增温为主，峰期温压均较高，峰期后为近等压冷却过程，它们反映地壳因岩浆底侵而增厚的动力学机制；第三类以辽东—吉南早元古代变质地带为代表，ＰＴｔ轨迹亦为逆时针，但特征是早期增压明显，继之以近等压增温，峰期为中低压，峰期后近等压冷却，这类样式反映了较稳定陆块壳内裂陷区的闭合过程。
The evolution of the Early Precambrian metamorphism and its PTt trajectory in the northern part of China and North Korea are divided into three types. The first type is the Jintin-Huai’an Archean high-level region in Inner Mongolia. The PTt trajectory is clockwise and the peak temperature Pressure up to 800 ℃ ~ 850 ℃, 0.90GPa ~ 1.00GPa, a significant thermal decompression after the peak, reflecting the tectonic plate thickening continental crust multiplied tectonic thickening and post-tensioning thinning mechanism; The second type is the Jidong-Liaoxi Archean high-level region, PTt is counterclockwise, with the main warming in the early stage and the warm and pressure in the peak period being high, and the near-pressure cooling process after the peak period. The third type is represented by the Liaodong-Jinaan Early Proterozoic metamorphic zone. The PTt trajectory is also counterclockwise, but the characteristic is that the early supercharging pressure is obvious, followed by the near-isobaric warming and peak period For the medium and low pressure, after the peak near-pressure cooling, these patterns reflect the closure of the continental shelf within the more stable block closure process.