Clay Mineralogy of Red Clay Deposits from the Central Carpathian Basin (Hungary): Implications for Plio/Pleistocene Chemical Weathering and Paleoclimate

Geochemical and mineralogical studies of palaeosols provide essential information for palaeoclimatic and palaeoenvironmental interpretation of continental deposits and can present a proxy for palaeoclimate. Red clays in the central Carpathian Basin (Hungary) (Tengelic Red Clay Formation; Kerecsend Red Clay Formation), overlain by loess-palaeosol sequences, were studied. Results from geochemical climofunctions applied to Upper Pliocene–Lower Pleistocene red clays and palaeosols located in the Carpathian Basin, and clay mineralogy, indicate that the palaeoclimate was considerably more humid and warmer during the Late Pliocene-Early Pleistocene in comparison to modern values

Grain size and mineralogical indicators of weathering in the Oberlaab loess-paleosol sequence, Upper Austria

Grain size analyses, bulk and clay mineralogical data were used to characterize weathering within the loess-paleosol-sequence of Oberlaab in Upper Austria. Soil horizons can be clearly identified by the calculation of weathering index Kd from granulometric parameters. The mineralogical composition of the bulk samples shows increasing weathering intensity from the top to the bottom. The weakest weathering stage 1 is not present in Oberlaab, because all samples are free of carbonate minerals. Weathering stage 2 can be found in the upper part of the profile, whereas stage 3 is mainly present in the lowermost horizons. The highest weathering stages 4 and 5 are not present in Oberlaab. The clay mineral distribution in the profile is dominated by the disappearance of primary chlorite in the upper part of the profile and the neoformation of vermiculites from illite by pedogenesis in the lower part. Two different types of mixed layer minerals were found in the pedocomplexes. An illite/chlorite mixed layer mineral occurs following the disappearance of chlorite and is present in the Eemian luvisol. The second mixed layer mineral consists of illite/vermiculite and is present in the whole profile. The weathering stages obtained from the clay mineral composition are slightly lower than that of bulk mineralogy, but reach as well stage 3 in the lower part of the profile.researc

BRONZE AGE POTTERY FROM TUROPOLJE AND PODRAVINA REGION – ARCHAEOMETRIC ANALYSIS

The paper presents results of the archaeometric analyses carried out on the Bronze Age pottery, found within the remains of settlements, located in the north-western part of Croatia (Turopolje and Podravina region). The main goal of this study is to determine the availability, types and characteristics of raw materials, as well as to reconstruct part of the technological process (preparation of raw material and firing technique) of pottery production. Potsherds are analysed using optical microscopy and X-ray powder diffraction (XRPD). Detailed mineralogical analysis (XRPD) with emphasis on clay minerals was performed on samples of potential raw material using oriented films of separated clay fraction and different treatments. Comparison between the data obtained from the analyses of potential raw materials and those obtained from the analyses of the pottery suggests that local clay was used for pottery making in the Bronze Age. Results of the study showed that raw material was probably collected in the vicinity of the settlements and that the grog is the most commonly used temper in the analysed samples from both regions. According to the results of performed analyses, there is an indication of a difference in technological choices, i.e. different practice related to pottery firing techniques, be- tween two micro-regions

Pedological and geochemical investigations at the „Red Outcrop“ of Langenlois (Lower Austria)

In einem Aufschluss von Löss-Paläoboden-Sequenzen über Rehberger Amphibolit NW von Langenlois wurden sechs Bodenprofile (Lois 1 bis Lois 6) beprobt und pedologisch, mineralogisch und geochemisch analysiert. Am Profil Lois 7 wurden bodenmikromorphologische Untersuchungen durchgeführt. Zwei Bodenprofile (Lois 1 und 2) haben sich über Amphibolit entwickelt, zwei über einer Amphibolit/Marmor-Wechsellagerung (Lois 5 und 6) und drei Bodenprofile sind Sequenzen von polyzyklischen Paläoböden mit fossilen Bodenhorizonten ohne unterlagerndes kristallines Gestein (Lois 3, 4 und 7). In den Profilen Lois 1–4 und Lois 7 konnten intensive Karbonatanreicherungen beobachtet werden. Diese hohen Mengen an Karbonat können nicht Produkt einer rezenten Bodenbildung sein, sondern sprechen für eine Infiltration von ursprünglich das Profil überlagernden kalzitreichen Sedimenten (Löss), die erodiert wurden. Zudem wurde in Profil Lois 2 ein Kalksinter angetroffen. Dieser Kalksinter könnte aus der Verwitterung der im Profil Lois 6 aufgeschlossenen Marmorlagen stammen. Die Kalksinter-Schicht scheint die Stoffflüsse zwischen unterliegendem Gestein und Solum in den Profilen Lois 1 und 2 mehr oder weniger zu unterbinden, was auch durch die Ergebnisse der geochemischen Analytik unterstrichen wird. In den fossilen Horizonten wurden auch ältere Anzeichen von Tonverlagerung in Form von Tonkutanen über den Aggregaten und darüber hinaus leichte Pseudovergleyungserscheinungen angetroffen. Die mächtigen Profile ohne aufgeschlossenes Grundgebirge (Lois 3, 4 und 7) weisen mehrere polyzyklische Sedimentationsphasen und dadurch mehrere Generationen von fossilen Horizonten auf. Aufgrund der bodenmikromorphologischen Analyse können die Böden vom „Roten Aufschluss“ altersmäßig im unteren bis mittleren Pleistozän oder älter angesiedelt werden.researc

Clay mineralogy of bauxites and palaeosols in Istria formed during regional subaerial exposures of the Adriatic Carbonate Platform

This excursion is largely based upon the Field Trip P8 (Regional Subaerial Unconformities in Shallow-Marine Carbonate Sequences of Istria: sedimentology, Mineralogy, Geochemistry and Micromorphology of Associated Bauxites, Palaeosols and Pedo-Sedimentary Complexes) of the 22nd IAS Regional Meeting held in Opatija, Croatia (DURN et al., 2003). Unlike the aforementioned fieldtrip, this excursion comprises 3 stops instead of 8, but data on clays are presented in more detail

Long-term soil warming decreases microbial phosphorus utilization by increasing abiotic phosphorus sorption and phosphorus losses

Phosphorus (P) is an essential and often limiting element that could play a crucial role in terrestrial ecosystem responses to climate warming. However, it has yet remained unclear how different P cycling processes are affected by warming. Here we investigate the response of soil P pools and P cycling processes in a mountain forest after 14 years of soil warming (+4 °C). Long-term warming decreased soil total P pools, likely due to higher outputs of P from soils by increasing net plant P uptake and downward transportation of colloidal and particulate P. Warming increased the sorption strength to more recalcitrant soil P fractions (absorbed to iron oxyhydroxides and clays), thereby further reducing bioavailable P in soil solution. As a response, soil microbes enhanced the production of acid phosphatase, though this was not sufficient to avoid decreases of soil bioavailable P and microbial biomass P (and biotic phosphate immobilization). This study therefore highlights how long-term soil warming triggers changes in biotic and abiotic soil P pools and processes, which can potentially aggravate the P constraints of the trees and soil microbes and thereby negatively affect the C sequestration potential of these forests

The Impact of Clay Minerals on the Building Technology of Vernacular Earthen Architecture in Eastern Austria

The vernacular architecture in many regions in Eastern Austria was characterized by the use of unfired clay, at least until the 19th century, and in some areas until the 20th century. Farmhouses and associated farm buildings, such as storage buildings or press houses for the production of wine and cider, were erected using different earth construction techniques. The study area stretches from the Weinviertel, a region located in the province of Lower Austria in the north-east of Austria, to the Burgenland, a region located in the south-east of Austria, which belonged to Western Hungary until 1921. From a geological point of view, in the east of Austria—in the Vienna Basin and the Molasse Zone—huge areas of Tertiary clay are covered with loess deposits, which is the best-known basic material used in local earth-building traditions. A core question in the research on vernacular earthen heritage focuses on the impact of the geological conditions in Eastern Austria on the local earth-building techniques. The mineralogical composition of the different clays had an impact on the local building techniques. From a material-culture point of view, research on the relationship between the mineralogical properties of clay resources and local building techniques sheds light on the factors which influenced the evolution of certain vernacular building features. Tertiary clays and loess from the Pleistocene favoured the making of earth lumps, cob walls and adobe bricks over the whole Eastern Austrian region. Contrarily, regions in Burgenland with a high amount of gravel preferred, by tradition, to make walls by ramming. The clay mineral smectite acts as a binding agent in earth-building techniques over the whole investigated region—Weinviertel, Burgenland and Western Hungary

The Impact of Clay Minerals on the Building Technology of Vernacular Earthen Architecture in Eastern Austria

The vernacular architecture in many regions in Eastern Austria was characterized by the use of unfired clay, at least until the 19th century, and in some areas until the 20th century. Farmhouses and associated farm buildings, such as storage buildings or press houses for the production of wine and cider, were erected using different earth construction techniques. The study area stretches from the Weinviertel, a region located in the province of Lower Austria in the north-east of Austria, to the Burgenland, a region located in the south-east of Austria, which belonged to Western Hungary until 1921. From a geological point of view, in the east of Austria—in the Vienna Basin and the Molasse Zone—huge areas of Tertiary clay are covered with loess deposits, which is the best-known basic material used in local earth-building traditions. A core question in the research on vernacular earthen heritage focuses on the impact of the geological conditions in Eastern Austria on the local earth-building techniques. The mineralogical composition of the different clays had an impact on the local building techniques. From a material-culture point of view, research on the relationship between the mineralogical properties of clay resources and local building techniques sheds light on the factors which influenced the evolution of certain vernacular building features. Tertiary clays and loess from the Pleistocene favoured the making of earth lumps, cob walls and adobe bricks over the whole Eastern Austrian region. Contrarily, regions in Burgenland with a high amount of gravel preferred, by tradition, to make walls by ramming. The clay mineral smectite acts as a binding agent in earth-building techniques over the whole investigated region—Weinviertel, Burgenland and Western Hungary