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以胶东群组合样及胶东群的主要岩性单元黑云变粒岩和黑云斜长片麻岩为初始物，在 １５０ ＭＰａ、水过饱和 条件下研究了胶东群地层在不同温度下（７４０ ℃，７７０℃，８１０℃，８５０℃）的熔融行为及熔体成分的演变。结果表明， 不同初始物的初熔温度、熔融程度及熔体产率差别很大，明显受源岩成分（ＳｉＯ_２－Ｋ_２Ｏ－Ｎａ_２Ｏ的相对比例）控制。黑云斜 长片麻岩由于ＳｉＯ_２：Ｋ_２Ｏ：Ｎａ_２０的比例（７３．０６：３．９２：２．５８）与花岗岩体系“最低点熔体”的比例（７９．２４：４．５７： ４．２５）接近，因而初熔温度低（在７４０～７５０℃之间），熔融程度高（８５０℃时为７５％左右）。黑云变粒岩（６３．３９：１．９９： ５． １１）则由于 ＳｉＯ_２和 Ｋ_２Ｏ质量分数明显降低，偏离“最低点熔体”较远，初熔温度升高（接近 ７７０ ℃），熔融程度大大降 低（８５０ ℃时为３０％左右）。对贫钾的源岩来讲，黑云母通过熔融分解向周围基质提供钾质，对源岩熔融具有明显的 促进作用。分熔熔体都含少量的刚玉标准分子（０．１０％～１．８４％），属弱过铝质。在Ｑ－Ａｂ－Ｏｒ图上，胶东群在８１０℃条件下熔融产生的熔体与尚庄斑状花岗岩成分一致，熔融程度约为３０％；?
Based on the Jiaodong group samples and the main lithologic unit biotite granodiorites and biotite plagioclase gneiss in the Jiaodong group, the formation of the Jiaodong group strata under different water temperatures (740 ℃, 770 ℃, 810 ℃, 850 ℃) and the evolution of melt composition. The results show that the initial melting temperature, the degree of melting and the melt yield of the different precursors vary widely and are obviously controlled by the source rock composition (the relative proportion of SiO 2 -K 2 O-Na 2 O). Because of the ratio of SiO_2: K_2O: Na_2O (73.06: 3.92: 2.58) to the “lowest point melt” of the granite system, the biotite plagioclase gneiss is 79.24: 4.57: 4. 25), the initial melting temperature is low (between 740 and 750 ° C) and the degree of melting is high (about 75% at 850 ° C). In the black-cloud granulite (63.39: 1.99: 5.11), the initial melting temperature (near 770 ° C) increased due to the significant decrease of the mass fraction of SiO_2 and K_2O, the deviation from the “lowest melting point” Degree greatly reduced (850 ℃ when about 30%). For poorly sourced source rock, biotite provides potassium to the surrounding matrix by melting and decomposing, which has a significant promoting effect on source rock melting. Molten melt contains a small amount of corundum standard molecules (0.10% to 1.84%), is a weak aluminum. In the Q-Ab-Or diagram, the melt produced by the Jiaodong Group at 810 ℃ is consistent with the composition of the Shangzhuang plagioclase granite, with a degree of melting of about 30%.