Mineralogical, geochemical, pedophysical and micromorphological properties of paleosol developed on the top of loess-paleosol sequence in Savudrija, Istria : master’s thesis

Cilj ovog rada bio je istražiti mineraloške, geokemijske, pedofizikalne i mikromorfološke značajke tla u vršnom dijelu pedosedimentnog kompleksa Savudrija. Terenskim istraživanjima uzeto je šest uzoraka tla, po jedan iz svakog od šest najviših horizonata, koja su podvrgnuta detaljnom opisu morfoloških svojstava. Laboratorijskim istraživanjima na uzorcima je napravljena detaljna kemijska analiza, fizikalno-kemijska analiza tla, uključujući CEC i saturaciju bazama, granulometrija, analiza željeza i mangana topivih u ditionitu i oksalatu, analiza mineralnog sastava, primjenom rendgenske difrakcije na prahu, određivanje starosti metodom optički (OSL) te infracrveno (IRSL) stimulirane luminiscencije te analiza mikromorfoloških preparata. Najvažniji zaključci ovog rada su: (1) Analizirani vršni dio pedosedimentnog kompleksa predstavljala su dva superponirana lesna supstrata unutar kojih su razvijena (paleo)tla. (2) Korištenjem geokemijskih omjera Sm/Nd te La/Ce, utvrđeno je isto podrijetlo lesnog supstrata u uzorcima. (3) Analizom rendgenske difrakcije na prahu utvrđeno je da svi uzorci sadrže kvarc (u znatnim udjelima), plagioklas, alkalijski feldspat, tinjčaste minerale (illit i muskovit), kaolinit, klorit, 14 Å minerale (vermikulite i/ili smektite), pretežno nepravilno interstratificirane miješanoslojne minerale, goethit te amorfnu komponentu. (4) Primjenom metoda optički i infracrveno stimulirane luminiscencije utvrđena je starost CB horizonta mlađeg lesnog supstrata te 2C horizonta starijeg lesnog supstrata. (5) Mikromorfološkom analizom utvrđen je znatan udio rizokonkrecija, željezovito-manganskih konkrecija te prevlaka glina, što ukazuje na intenzivnu iluvijaciju u horizontima vršnog dijela pedosedimentnog kompleksa Savudrija.Abstract: The aim of this Thesis was to investigate mineralogical, geochemical, pedophysical and micromorphological properties of soil in the uppermost part of the Savudrija pedosediment complex. Field investigation included taking six samples, one from each of the six investigated uppermost soil horizons and submitting them to a detailed morphological description. Laboratory work consisted of a detailed chemical analysis, physical and chemical analysis of the paleosols, including measurements of CEC and base saturation, particle size analysis, analysis of iron and manganese oxides and hydroxides soluble in dithionite-citrate bicarbonate and oxalate, mineral composition analysis, using the XRD method, optical and infrared stimulated luminescence and a micromorphological analysis of thin sections. The most important conclusions of this Thesis are as follows: (1) Analyzed uppermost part of the pedosediment complex was represented by two superimposed loess parent materials within which (paleo)soils have developed. (2) With the usage of geochemical ratios of Sm/Nd and La/Ce it is determined that the loess parent material investigated in this Thesis has the same provenance. (3) According to the results of analysis using the X-ray diffraction method, it is determined that all soil samples contain a significant share of quartz, plagioclase, alkali feldspar, illitic material, kaolinite, chlorite, 14 Å minerals (vermiculite and/or smectite), mostly irregular mixed layer clay minerals, goethite, and amorphous component. (4) Usage of optically and infrared stimulated luminescence determined the age of analyzed soil horizon CB and soil horizon 2C. (5) Micromorphological studies have shown a significant share of rhizoconcretions, ferrous-manganese concretions and clay coatings, which indicates a significant illuviation in horizons of the uppermost part of the Savudrija pedosediment complex