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在大别山北麓晚侏罗世凤凰台组砾岩中发现了榴辉岩砾石．榴辉岩退变质作用较强，尚残存的主要矿物有石榴石、多硅白云母、石英、金红石、斜黝帘石、指纹（或蠕虫）状后成合晶和赋存在石榴石中的柯石英假象包体．石榴石端员组分主要为钙铝榴石 ２７．７％～３７．８％，铁铝榴石４５．５％～４９．０％，镁铝榴石１２．３％～２５．７％，镁铝榴石端员组分＜３０％，相当于Ｃ类榴辉岩．多硅白云母中硅阳离子为３．４４～３．５４ｐ．ｆ．ｕ．（以 Ｏ＝１１为基准），经估算其压力为２．５～３．２ ＧＰａ，温度为 ６００～９００℃．指示大别高压－超高压变质岩自三叠纪形成之后，经折返抬升至晚侏罗世之前已经到达地表．
Eclogite gravels were found in the Late Jurassic Phoenix Group conglomerate in the northern foot of the Dabie Mountains. The eclogites are characterized by retrogressive metamorphism and the main remaining minerals are garnet, picei, quartz, rutile, diabase zonite, fingerprinting (or worm) -like post-conglomeration and coesite present in garnet Imagination package. Garnet end members are mainly composed of 27.7% -37.8% of goat, 45.5% -49.0% of almandine, 12.3% -25.7% of gypsum, Mg-Al-garnet end member <30%, equivalent to Class C eclogite. Siliceous mica in the silicon cations 3.44 ~ 3.54p. f. u. (Based on O = 11), the pressure is estimated to be 2.5 ~ 3.2 GPa, the temperature is 600 ~ 900 ℃. It indicates that the Dabie UHP-UHP metamorphic rocks have reached the surface before Triassic uplift and uplift to Late Jurassic.