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Transitional eclogite were found recently at Haiyangsuo, Rushan County, and eastern Shandong Peninsula.It shows metamorphic transformation from granulite to plagioclase-bearing transitional eclogite. Thegranulite-factes assemblage (GTt-I + Cpx-I + Opx + PI-I + Hbl-I + Ilm) is equilibrated at temperature of780-830 ℃ and pressure of 8-9 kbar. Its granular textures are well preserved in the less deformed rock.With the development of the shearing deformation accompanied by fluid infiltration during the transitionaleclogite factes, the granulitic assemblage transformed to a transitional eclogitic paragenesis (Cpx-Ⅱ(Omp/Di) + Grt-Ⅱ + PI-Ⅱ (Ab) + Rut + Qtz + Ky + Zo + Tlc) with various degree. Mineral compositions ofthe transitional eclogite factes give P-T conditions of 560-680 ℃ and 10-14 kbar (up to 18 kbar), Whichare much lower than those of the coesite-eclogite in the Su-Lu ultrahigh-pressure (UHP) metamorphic belt,located to the southwest and northeast of the Haiyangsuo. The Haiyangsuo transitional eclogite mayrepresent the counterpart of the “cold eclogite” in southern pan of the Dabieshan high-pressure belt, anddelineates the position of the southern margin of the Su-Lu UHP metamorphic belt.
Transitional eclogite were found recently at Haiyangsuo, Rushan County, and eastern Shandong Peninsula. It shows metamorphic transformation from granulite to plagioclase-bearing transitional eclogite. Thegranulite-factes assemblage (GTt-I + Cpx- I + Opx + PI- I + Hbl- I + Ilm) is equilibrated at temperature of 780-830 ° C and pressure of 8-9 kbar. Its granular textures are well preserved in the less deformed rock. The development of the shearing deformation accompanied by fluid infiltration during the transitional phase logites, the granulitic assemblage transformed to a transitional eclogitic paragenesis (Cpx-II (Omp / Di) + Grt- II + PI- II (Ab) + Rut + Qtz + Ky + Zo + TIc) with various degrees. Mineral compositions of the transitional eclogite factes give PT conditions of 560-680 ° C and 10-14 kbar up to 18 kbar, Whichare much lower than those of the coesite-eclogite in the Su-Lu ultrahigh-pressure (UHP) metamorphic belt, located to the southwest and northeast of the Haiyangsuo. The H aiyangsuo transitional eclogite mayrepresent the counterpart of the “cold eclogite” in southern pan of the Dabieshan high-pressure belt, and delineates the position of the southern margin of the Su-Lu UHP metamorphic belt.