Progressive Metamorphism and Granitization of the Major Paragneiss, Northwest Adirondack Mountains, New York

Interstratified vermiculite–mica in the gneiss–metapelite–serpentinite rocks at Hafafit area, Southern Eastern Desert, Egypt: From metasomatism to weathering

“…The field of trioctahedral vermiculites (Föster, 1963) is also given for comparison. TEP = Tetra-ferri-phlogopite; (D) (FeO + MnO)-(Fe 2 O 3 + TiO 2 )-MgO ternary of Engel and Hugel (1960). Dot line drawn by Gokhale (1968) to discriminated between magmatic and metamorphic-metasomatic micas; (E) MgO-FeO t -Al 2 O 3 ternary (after Nockolds (1957)).…”

Tectonic significance of the Xilin Gol Complex, Inner Mongolia, China: Petrological, geochemical and U–Pb zircon age constraints

“…4, after Foster, 1960). It has high values of Mg/(Mg + Fe) (0.46-0.47) and Ti (0.16-0.17), and low Al VI (0.38-0.42) ( Table 2), which suggest a medium-grade metamorphic origin (Engel and Engel, 1960; Robert, 1976;Dymek, 1983). Zhao et al (2002) reported the metamorphic temperature of 540-550°C determined by amphibole-plagioclase thermometry on hornblende-plagioclase gneiss from the Xilin Gol Complex.…”

Retrograde contact meta-morphism in the granulite facies terrain of Mont Tremblant Park, Quebec, Canada

“…The retrograde hornblende is blue-green to grass-green as opposed to the characteristic deep greenish-brown variety found in the granulites. The retrograde biotite is green-brown to very dark brown or almost black compared to the shades of dark brown and red-brown found in the higher grade rocks (Engel &Engel, 1960 and1962).…”