In the Su-Lu ultrahigh-P terrane, eastern China, many coesite-bearing eclogite pods and layers within biotite gneiss occur together with interlayered metasediments now represented by garnet-quartz-jadeite rock and kyanite quartzite. In addition to garnet + omphacite + rutile + coesite, other peak-stage minerals in some eclogites include kyanite, phengite, epidote, zoisite, talc, nyboite and high-Al titanite. The garnet-quartz-jadeite rock and kyanite quartzite contain jadeite + quartz + garnet + rutile f zoisite f apatite and quartz + kyanite + garnet + epidote + phengite + rutile f omphacite assemblages, respectively.Coesite and quartz pseudomorphs after coesite occur as inclusions in garnet, omphacite, jadeite, kyanite and epidote from both eclogites and metasediments. Study of major elements indicates that the protolith of the garnet-quartz jadeite rock and the kyanite quartzite was supracrustal sediments. Most eclogites have basaltic composition; some have experienced variable 'crustal' contamination or metasomatism, and others may have had a basaltic tuff or pyroclastic rock protolith.The Su-Lu ultrahigh-P rocks have been subjected to multi-stage recrystallization and exhibit a clockwise P-T path. Inclusion assemblages within garnet record a pre-eclogite epidote amphibolite facies metamorphic event. Ultrahigh-P peak metamorphism took place at 700-890" C and P > 28 kbar at c. 210-230 Ma. The symplectitic assemblage plagioclase + hornblende f epidote f biotite + titanite impIies amphibolite facies retrogressive metamorphism during exhumation at c. 180-200 Ma. Metasedimentary and metamafic lithologies have similar P -T paths. Several lines of evidence indicate that the supracrustal rocks were subducted to mantle depths and experienced in-situ ultrahigh-P metamorphism during the Triassic collision between the Sino-Korean and Yangtze cratons.

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Equilibrium pressure-temperature (P-T) conditions were estimated for kyanite-bearing eclogite from Nove´Dvory, Czech Republic, by using garnet-clinopyroxene thermometry and garnet-clinopyroxenekyanite-coesite (or quartz) barometry. The estimated P-T conditions are 1050-1150°C, 4.5-4.9 GPa, which are mostly the same as previously estimated values for garnet peridotite from Nove´Dvory (1100-1250°C, 5-6 GPa). Such very high-P conditions, which correspond to about 150-km depth, have been obtained for some garnet peridotites in the Gfo¨hl Unit of the Bohemian Massif, but pressure conditions of eclogites associated with the garnet peridotites have not been so well constrained. This is the first substantial finding of eclogite that gives such very high-P conditions in the Gfo¨hl Unit of the Bohemian Massif. The Gfo¨hl Unit mainly consists of felsic granulite or migmatitic gneiss, but these rock types do not display high-P (>2.5 GPa) evidence. It is unclear whether both the peridotite body and surrounding felsic rocks in the Gfo¨hl Unit were buried to very deep levels, but at least some garnet peridotites and associated eclogites in the Gfo¨hl Unit have ascended from about 150-km depth.