Petrified Wood Occurrences in Western Thrace and Limnos Island: Mineralogy, Geochemistry and Depositional Environment

Abstract

The present study describes the geology and mineralogy of the main petrified wood occurrences in Evros-Rhodopi and Limnos and integrates them in a volcanichydro thermal framework taking into consideration the nature of hydrothermal solu-

Amethyst Occurrences in Tertiary Volcanic Rocks of Greece: Mineralogical, Fluid Inclusion and Oxygen Isotope Constraints on Their Genesis

“…Smectite, zeolites and calcite are accessory minerals both within the veins and in the wall rocks ( Figure 4b). Similar to Kassiteres-Sapes area, in the broad Kornofolia area, the amethyst-chalcedony veins crosscut fossiliferous limestone reefs and silicified wood hosted in volcano-sedimentary layers, thus suggesting a very shallow submarine to transitional environment [41], and accordingly a very shallow depth of amethyst formation, probably close to the seafloor. Unaltered to zeolite-altered lavas of dacitic composition are the host rocks of chalcedonyamethyst bearing NNW-trending veins at Kirki area, in a locality resembling that of Kornofolia (Figures 1b and 3f).…”

“…Prismatic amethyst crystals are rare. The presence of silicified wood within the tuffs hosting amethyst veins at Kassiteres-Sapes area, and the observation that the amethyst veins crosscut the fossilized wood [41], indicate probably a very shallow environment for amethyst deposition.…”

Palaeoxylotomical studies in the Cenozoic petrified forests of Greece. Part one – palms

“…Synthesizing previous views on the geological evolution of Evros, Voudouris et al (2007) showed that the main phase of Cenozoic magmatism took place during the Oligocene until the earliest Miocene (Innocenti et al 1984, Del Moro et al 1988 and is represented by submarine/terrestrial volcanic and subvolcanic rocks. Christofides et al (2004) give radiometric ages of 30-28 Ma for the area north of Tycheron, which suggests late Rupelian/early Chattian age.…”

“…According to Kopp (1965), Petrescu et al (1980) and Velitzelos et al (2002), the fossil plants are related mainly to the Rupelian-Chattian lignite-bearing volcano-sedimentary levels of the Provatonas series (around Fylakto village), which discordantly cover the volcanics. Coral reefs and abundant mollusks within the silt layers, indicating a shallow marine environment, have been observed (Kopp 1965, Voudouris et al 2007. Around Lefkimi village, rocks of rhyolitic and andesitic composition appear in a submarine environment (as hyaloclastites) and are overlain by coral-bearing reefs and then by fine-grained volcano-sedimentary layers including silicified wood.…”

“…It is most probably a lahar generated by unstable volcanic superstructures mobilized by, for example, catastrophic rainfall. The volcanic material was transported as flows of cold volcanic unsorted mud, or as pebbles from reworked volcanic rocks (lavas, volcanic bombs, lapili, coarse pyroclastics, volcanic ash) often mixed with terrigenous material and sedimented in the neighboring marine basin, sometimes also preserving nearby fossil wood and other vegetal remains (leaf or fruit impressions), bones of terrestrial animals and shallow-water mollusks or corals which have been found and documented (Voudouris et al 2007).…”