Texture and mineralogical composition of Quaternary terrestrial and marine sediments from Macedonia and Thrace, Greece

Abstract

Clastic sediments collected from land and gulfs of Macedonia and Thrace in Greece are examined on the basis of their texture and mineral composition. All terrestrial samples are coarse-grained and poorly sorted, with angular to sub-angular grains. These are mainly composed of quartz and feldspars, followed by micas, calcite and Fe-Mg minerals. Among the clay minerals illite predominates over smectite and smectite over vermiculite (+chlorite+kaolinite). In addition, the interstratified phases illite/smectite, chlorite/vermiculite, and smectite/vermiculite are present in significant amounts in the clay fraction (<2 μm), signifying the incomplete weathering of the primary minerals. Mixing during transportation, flocculation, differential settling processes and organic matter are the main mechanisms for the distribution of the discharged terrigenous load into the North Aegean Gulfs. All gulf bottom samples are coarse to fine grained and medium sorted, and their grains are angular to sub-angular. Quartz and feldspars predominate. In addition, biogenic calcite, micas and various Fe-Mg minerals exist as primary and/or accessory minerals. Among clay minerals, illite predominates over smectite and smectite over kaolinite (+chlorite+vermiculite). Almost in all gulf sediments the interstratified phase illite/smectite is apparent. The presence of feldspars and Fe-Mg minerals, as well as the high content of clay minerals and the polymodal grain-size distribution with angular to sub-angular grains, signify mineralogical and textural immaturity of all the examined sediments, as well as predominance of mild climatic conditions and thus mild weathering processes. The quartz content in these sediments is usually <70%. Therefore, a sedimentation cycle of these materials has not been completed.

The Late and the Latest Pleistocene Chiroptera (Mammalia) from Loutra Almopias Cave a (Pella, Macedonia, Greece)

“…The geology, stratigraphy and speleogenesis of LAC A and the broader region of the Almopia Speleopark have been extensively described in the past (Tsirambides, 1998, 2006; Chatzopoulou et al ., 2001; Chatzopoulou, 2003, 2005 a , 2005 b , 2014; Lazaridis, 2005, 2006; Tsoukala et al ., 2006; Georgiadis et al ., 2019). Six chambers are present in the cave (Fig.…”

“…LAC A (also known as Loutra Arideas Cave and/or Bear Cave) is located on the northern slope of the Nikolaou Rema gorge at an altitude of 540 m and the coordinates of the entrance are 40°58'23.7"N, 21°54'31.3"E. It develops on the boundary between the Pelagonian zone (west) and the Almopias subzone (east) and more precisely in a Maastrichtian limestone (Tsoukala and Rabeder, 2005;Tsoukala et al, 2006) The geology, stratigraphy and speleogenesis of LAC A and the broader region of the Almopia Speleopark have been extensively described in the past (Tsirambides, 1998(Tsirambides, , 2006Chatzopoulou et al, 2001;Chatzopoulou, 2003Chatzopoulou, , 2005aChatzopoulou, , 2005bChatzopoulou, , 2014Lazaridis, 2005Lazaridis, , 2006Tsoukala et al, 2006;Georgiadis et al, 2019). Six chambers are present in the cave (Fig.…”

Determination of available heavy metal concentrations in River Nile sediments, Damietta, Egypt

“…Most heavy metals in the aquatic environment can be indifferently deposited in the bottom sediments (Salomons et al, 1995). The sediments are composed of different components, which include carbonates, quartz, clay minerals, feldspar, and organic matter (Tsirambides, 1992(. In the river sediments; heavy metals have divided into three groups of components: Erosional and weathering of rocks and solid origin (Detrital solids), water column processes origin (Endogenic fractions), and sediments process (Diagenetic fractions) (Förstner et al, 1976;Jones and Bowser, 1978).…”