Structural development of high-pressure metamorphic rocks on Syros island (Cyclades, Greece)

Kinematic reconstructions and magmatic evolution illuminating crustal and mantle dynamics of the eastern Mediterranean region since the late Cretaceous

“…Exhumation of these metamorphic units first occurred between 45 and 35-30 Ma in a syn-orogenic context, following a cold retrograde path (figure 5) [Altherr et al, 1979;Bonneau and Kienast, 1982;Avigad and Garfunkel, 1989;Trotet et al, 2001]. These Eocene HP-LT parageneses are particularly well preserved in the Syros and Sifnos islands where syn-orogenic extensional shear zones, such as the Vari detachment in Syros (figure 6), show top-to-the ENE and top-to-the N senses of shear, respectively (figure 3) [Trotet et al, 2001;Keiter et al, 2004;Ring et al, 2011;Roche et al, submitted]. In the Ios island, a coeval top-to-the S structure called the South Cycladic Shear Zone (SCSZ) is observed at the base of the Cycladic Blueschists unit (figure 6).…”

Partitioning and budget of Li, Be and B in high-pressure metamorphic rocks

“…Hecht, 1984;Dixon and Ridley, 1987;Seck et al, 1996). The petrological, structural and tectono-metamorphic evolution of the island of Syros has been investigated in a large number of studies (Dixon, 1968;Bonneau et al, 1980;Ridley, 1982Ridley, , 1984Ridley, , 1986Ballhaus and Schumacher, 1995;Trotet et al, 2001a;Rosenbaum et al, 2002;Ring et al, 2003;Brady et al, 2004;Keiter et al, 2004). For different rock types, a prograde P-T path was derived, characterised by a high P/T ratio, typical for subduction zone metamorphism.…”

“…For different rock types, a prograde P-T path was derived, characterised by a high P/T ratio, typical for subduction zone metamorphism. Metamorphic peak conditions were estimated at $470-520°C and 1.3-2.0 GPa (Dixon, 1968;Ridley, 1984;Okrusch and Brö cker, 1990;Trotet et al, 2001b;Rosenbaum et al, 2002;Keiter et al, 2004). The most interesting formations are exposed in the northern part of Syros near Kámpos and at the coastline around Hermoupolis and Kini.…”

Strain localization in a fossilized subduction channel: Insights from the Cycladic Blueschist Unit (Syros, Greece)

“…The contact between Chroussa and Kampos subunits is well exposed in the northern 471 part of the island, along the Kampos metabasite belt ( Fig. 10; see also Keiter et al, 2004Keiter et al, , 472 2011). This metabasic unit shows an E-W orientation and dips toward the north on the 473 western side.…”