Mineralogical, geochemical, pedophysical and micromorphological properties of paleosol developed on the bottom of loess-paleosol sequence in Savudrija, Istria

Autor: Baniček, Ivona
Přispěvatelé: Durn, Goran, Sondi, Ivan, Ružičić, Stanko
Jazyk: chorvatština
Rok vydání: 2016
Předmět:
Popis: Cilj ovog rada bio je istražiti mineraloške, geokemijske, pedofizikalne i mikromorfološke značajke tla razvijenog na glacijalnom lesu Savudrije. Terenskim istraživanjima detaljno su opisana morfološka svojstva horizonata te su uzeti uzorci duž cijelog pedosedimentnog kompleksa. Fokus istraživanja ovog rada je stratigrafski najdonji dio profila koji obuhvaća četiri uzorka lesa i crvenog paleotla. Laboratorijskim istraživanjima napravljena je detaljna kemijska analiza, analiza željeza i mangana topivih u ditionitu i oksalatu, fizikalno-kemijska analiza tla, granulometrija, analiza mineralnog sastava primjenom rendgenske difrakcijske analize, optički (OSL) i infracrveno (IRSL) stimulirana luminiscencija te mikromorfološka analiza preparata. Najvažniji zaključci ovog rada su: (1) Istraživanja su pokazala da je crveno paleotlo nastalo procesom ocrvenjivanja (rubifikacije) dominantno lesnog supstrata. Prije nastanka crvenog paleotla na površini krednog vapnenca, postojalo je još starije tlo koje je erodirano. Dokaz tomu su brojni pedorelikti koji su pronađeni u crvenom paleotlu, a predstavljaju djeliće tog starijeg paleotla. Procesi dekalcifikacije i bisialitizacije su bili izrazito važni tijekom trošenja paleotala. Terenskim istraživanjima utvrđeni su slijedeći horizonti: Ck2 (4910) – BC (4906) – Bg2 (4907) – Bg (4908) – R (prema WRB, 2006). (2) Starost pedosedimentnog kompleksa odgovara OIS-4 stadiju. Najdonji uzorak (SAV 1; pozicija uzorka 4907) (Bg2) uslijed pedogenetskih procesa ima vjerojatno podcijenjenu starost. (3) Frakcija čestica glina svih analiziranih uzoraka sadrži tinjčaste minerale, dobro i loše kristaliziran kaolinit, getit, 14 Ǻ minerale i miješanoslojne minerale glina. S obzirom na mineralni sastav, udjele DCB topivih Fe oksida te odsustvo glinenih prevlaka, važno je istaknuti da se crveno paletlo pedosedimentnog kompleksa Savudrije razlikuje od većine crvenica do sada istraživanih u Istri.
The aim of this Thesis is to investigate mineralogical, geochemical, pedophysical and micromorphological properties of the soil that is developed on glacial loess on the Savudrija peninsula. During the field investigation, the morphological properties of each horizon were described in detail and samples were taken along the pedosediment complex. This Thesis is focused on the lowermost part of the profile which includes four samples of loess and red paleosol. Laboratory work consisted of a detailed chemical analysis, analysis of iron and manganese oxides and hydroxides soluble in oxalate and dithionite, physical and chemical analysis of the paleosols, particle size analysis, mineral composition analysis using the X-ray diffraction method, optical and infrared stimulated luminescence and lastly, a micromorphological analysis of thin sections. The most important conclusions of this Thesis are as follows: (1) The investigation showed that the red paleosol formed by the process of rubification from a dominant loess parent material. Prior to this, there was an older paleosol situated on the surface of the Cretaceous limestone, but it was eroded. This is proved by the presence of pedorelicts found in the red paleosol which represent fragments of this older paleosol. The processes of decalcification and bisialitization were important during the formation of the paleosol. The following horizon stratification was formed: Ck2 (4910) – BC (4906) – Bg2 (4907) – Bg (4908) – R (WRB, 2006). (2) The age of the pedosediment complex correlates with the OIS-4 stage. The lowermost sample SAV 1 corresponds to the 4907 (Bg2) sample and probably has an underestimated age due to pedogenic processes. (3) ) The clay fraction of all analysed samples contains illitic material, good and poorly crystallized kaolinite, goethite, 14 Ǻ minerals and mixed layer clay minerals. Mineral composition, content of dithionite soluble iron and the lack of clay coatings clearly indicate that the red paleosol situated at the bottom of Savudrija pedosedimentary complex is different from the majority of terra rossa soils in Istria.
Databáze: OpenAIRE
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