EGU21-14619
https://doi.org/10.5194/egusphere-egu21-14619
EGU General Assembly 2021
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Red-coloured pedosediments of the Lori Basin, Armenia 

Anna Revunova1 and Olga Khokhlova2
Anna Revunova and Olga Khokhlova
  • 1Saint Petersburg State University, Institute of Earth Sciences, Dept. of Soil Science & Ecology of Soils, Russian Federation (reina_abc@mail.ru)
  • 2Institute of Physicochemical and Biological Problems of Soil Science, Russian Academy of Sciences, 142290, Pushchino, Russia

In this work, the samples of red-coloured pedosediments were analyzed. They were found in two sections of the Lori Basin, Armenia - Kurtan-IV and Yagdan. Micromorphological analysis, the measurement of magnetic susceptibility, particle size distribution, CHN, determination of bulk, and biomorphic composition was made. Based on the results of previous studies, the age of the deposits overlying these sections was known. The pedosediment from the Kurtan-IV section is overlain by a mixture of sand and volcanic ash, which is dated at about 1.4 Ma (Calabrian). The pedosediment from the Yagdan section is overlain by 2-2.5 Ma basaltic lava (Gelasian). As a result of our research, it was revealed that both pedosediments were formed in conditions differ from current ones and have differences between themselves also. The pedosediment from the Yagdan section was formed during the dominance of the subtropical climate. It was revealed the presence of manganese-ferruginous and clayey films, a low index of carbonization and salinity, and a relatively high index of weathering. Pedo-sediments from the Yagdan section can be classified as Cambisols with vitric, argic, chromic qualifiers. By the time the later section Kurtan-IV was formed, the climate became cooler, which was reconstructed by the appearance of phytoliths of coniferous plants. Pedosediment from the Kurtan-IV section can be classified as Stagnic Luvisols. The later factors influencing the preservation of pedosediments and changes in their composition and properties were identified. Thus, the upper horizon of the Yagdan section sharply differs from the underlying ones in increased weathering and oxidation, and these properties are retained up to the third layer. It has increased indicators of magnetic susceptibility and the content of copper elements, cobalt, nickel, vanadium, chromium, which were brought in by basalt lava. The pedosediment from the Kurtan-IV section was overlain by lacustrine deposits, which led to a decrease in the magnetic susceptibility and an increase in the SiO2 content and carbonation index. This work was supported by RFBR, grant N19-29-05024 mk.

How to cite: Revunova, A. and Khokhlova, O.: Red-coloured pedosediments of the Lori Basin, Armenia , EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-14619, https://doi.org/10.5194/egusphere-egu21-14619, 2021.

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