PROMJENE U ZAJEDNICI MINERALA GLINA U TLIMA RAZVIJENIM U UMJERENOJ KLIMI NA MIOCENSKIM I PLIOKVARTARNIM SEDIMENTIMA MEDVEDNIČKOGA PRIGORJA, SZ HRVATSKA

doctoral thesis

• Title (english): CHANGES IN CLAY MINERALOGY IN SOILS DEVELOPED IN TEMPERATE CLIMATE ON MIOCENE AND PLIO-QUATERNARY SEDIMENTS OF MEDVEDNICA MT., NW CROATIA
• Author: Zvonka Gverić
• Mentor: Nenad Tomašić (mentor)
• Mentor: Vedran Rubinić (komentor)
• Committee member: Hana Fajković (predsjednik povjerenstva)
• Committee member: Goran Durn (član povjerenstva)
• Committee member: Anita Grizelj (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Geology); Zagreb
• Defense date and country: 2023-12-14, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Geology
• Universal decimal classification (UDC): 55 - Geology. Meteorology. Hydrology

Abstract

Istraživani su mineraloški i geokemijski potpisi trošenja u tlima razvijenim na miocenskim i pliokvartarnim sedimentima. Istraženo je 5 profila tla na miocenskim laporima i glinovitim vapnencima i 3 profila na pliokvartarnim sedimentima, smještenim na JI obroncima Medvednice. Na uzorcima tala i sedimenata napravljene su pedološke, mineraloške i kemijske analize. Tla na miocenskim sedimentima su prema međunarodnom WRB sustavu klasificirana kao Leptosoli, Regosoli i Cambisol. Profili na pliokvartarnim sedimentima nisu pedološki klasificirani, međutim, uz iznimku profila koji ima obilježja Stagnosola, preostala dva profila ukazuju na nizak intenzitet pedogeneze, kao i profili na miocenskim sedimentima. Zajednica minerala glina se u miocenskim sedimentima sastoji od dominantnog illit-smektita, te illita i kaolinita, s pojavom vermikulita i klorita u nekim uzorcima. U pliokvartarnim sedimentima dominiraju bubreći minerali glina (smektit i vermikulit), a sadrže još illit i kaolinit te ponegdje Fe i Al (oksi)hidrokside. Promjene zajednice minerala glina u tlima na miocenskim sedimentima uključuju smanjenje količine illita i illitnih slojeva i pojavu prijelaznog klorit-vermikulita, dok su kod tala na pliokvartarnim sedimentima obilježene dominantno bubrećim mineralima višeg naboja sloja (vermikulit) i/ili pojavom hidroksi-interstratificiranih minerala. Mineraloški potpis u profilima na miocenskim karbonatnim sedimentima upućuje na niži intenzitet trošenja pod utjecajem visokog pH i pedogeneze koja se odvija u uvjetima recentne umjerene klime i značajne erozije na nagnutom terenu. Profili na pliokvartarnim sedimentima u samom sedimentu sadrže produkte tipične za intenzivnije trošenje, dok u tlu sadrže produkte transformacije minerala glina u skladu s recentnim uvjetima umjerene klime. Geokemijski podaci generalno potvrđuju mineraloški zapis te dodatno pokazuju homogenost u miocenskim sedimentima taloženim u pretežno marinskim i jezerskim okolišima te heterogenost u proluvijalno-koluvijalnim pliokvartarnim sedimentima koji u sebi nose mineraloške i geokemijske informacije pretaloženih starijih naslaga.

Abstract (english)

Mineralogical and geochemical weathering signatures in soils developed on Miocene and Plio-Quaternary sediments were investigated. Five soil profiles on Miocene marls and argillaceous limestone and three soil profiles on Plio-Quaternary sediments on SE slopes of Mt. Medvednica were selected for the study. Soil and sediment samples were analyzed and their pedological, mineralogical and geochemical properties were determined. Soils on Miocene sediments were classified according to WRB system as Leptosols, Regosols and Cambisol. Soils on Plio-Quaternary sediments were not classified; however, aside from one profile showing Stagnosol properties, the remaining two profiles, like the profiles on Miocene sediments, are initially developed. Clay mineralogy of Miocene sediments is dominated by illite-smectite and contains illite and kaolinite with vermiculite in most and chlorite present in some samples. Plio-Quaternary sediments are dominated by expandable clay minerals (smectite and vermiculite) and contain illite and kaolinite as well as Fe and Al (oxy)hydroxides in some samples. The changes in clay mineralogy in soils on Miocene marls include a decrease in illite and illite layers in illite-smectite, and the appearance of mixed-layered chlorite-smectite. These changes in soils on Plio-Quaternary sediments are marked by dominant expandable clay minerals of higher layer charge (vermiculite) and/or hydroxyl-interlayered minerals. Mineralogical weathering signature in the profiles developed on Miocene carbonates indicates lower weathering intensity influenced by high pH and pedogenesis progressing in the recent temperate climate conditions as well as erosion on sloping terrain. Plio-Quaternary profiles contain minerals typical of more intense weathering in the sediments samples, while the soil shows clay minerals transformation products in line with recent temperate climate conditions. Geochemical weathering signatures generally confirm these results. The geochemistry of the samples also shows homogeneity in Miocene sediments deposited mainly in marine and lacustrine environments and heterogeneity in proluvial and colluvial Plio-Quaternary sediments, which carry mineralogical and geochemical signatures of re-deposited older sediments.

• Keywords: lapor; proluvijalno-koluvijalne naslage; tlo; mineralogija glina; trošenje; pedogeneza; paleookoliš; miocen; pliokvartar; Medvednica
• Keywords (english): marl; proluvial-colluvial sediments; soil; clay mineralogy; weathering; pedogenesis; paleoenvironment; Miocene; Plio-Quaternary; Medvednica Mt.
• Language: croatian
• URN:NBN: urn:nbn:hr:217:245609
• Promotion: 2024
• Study programme: Title: DOCTORAL STUDY OF GEOLOGY; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti u području prirodnih znanosti (doktor/doktorica znanosti u području prirodnih znanosti)
• Type of resource: Text
• Extent: 158 + IX str. ; 30 cm
• File origin: Born digital
• Access conditions: Open access
• Created on: 2025-01-30 12:04:50