Physical and Geological Sciences

ABSTRACT The Triassic Glykomilia trachyandesites of the Koziakas mountain range (western Thessaly) are parts of the oldest volcanic series in continental central Greece. Rock fragments and blocks of pillowed alkali basalts, which are dispersed into the Koziakas ophiolite mélange, display similar subparallel chondrite-normalized trace and rare earth element patterns to the trachyandesites, suggesting cogenetic origin.

ABSTRACT A metasomatic episode that involved contact metasomatism of inferred calcitic veins within basalt and gabbro has been identified in Samothraki island. It has resulted in a zonal arrangement of anhydrous and hydrous assemblages. Relative to a hypothetical calcite/epidote assemblage as precursor, the skarns gained Si, Mg, Na and Fe+ 3 while they lost Ca and CO2. REE were mobile due to a high water/rock ratio, which is likely to have resulted from convective fluid flow.

ABSTRACT Petrographic observation of sandstones that contain detrital grains and lithic fragments along with microanalytical data from certain minerals suggest that detrital material in Pindos flysch deposits, in Metsovo and Fourna areas, may have been sourced in the Pindos ophiolite and the Pelagonian metamorphic rocks; additionally some material from Fournas has probably been derived from the Koziakas ophiolite outcrop.

Abstract The relationships between petrographic and physicomechanical properties of basic igneous rocks from the Pindos ophiolitic complex, northwestern Greece, were investigated. The mineralogical composition was quantified from one polished thin section per sample with a polarizing microscope, by using the point count method. Textural description was also carried out by using both polarizing and scanning electron microscope.

Abs tract Geological mapping and field evidence in Samothraki island have determined five lithological units. The lowermost formation is the Basement Unit; it consists of low-grade metamorphic rocks which display structures analogous to rift formations. The Ophiolite Unit occupies the dominant area of the island resting conformably on the Basement Unit. It is composed of cumulate and non-cumulate gabhros, diorites. massive dolerite and basalt which are locally intruded by doleritic dykes.

Abstract: The island of Samothraki has a complex of gabbro-diabase-diorite that cuts sediments with Oxfordian age fossils. The mafia component of this sequence has been interpreted as an autochthonous ophiolite. Two diorite samples yielded K/'Ar ages on hornblende of 154 and 155 my. These dates are similar to those from granitoids and diorites from Guevgeli ophiolite, one of the “innermost Hellenic ophiolite belt”(IMHOB).