@conference{
author = "Kašanin-Grubin, Milica and Stefanović, Milica and Jovančićević, Branimir and Šajnović, Aleksandra",
year = "2019",
abstract = "Badlands are worldwide erosional landforms. The
formation of different badland morphologies is due to
the type of sedimentary bedrock, especially texture
and cementation degree, as well as climate.
In this study badlandes mudstones which have high
silt and clay contents from different locations in Italy,
Spain and Canada (Figure 1) were investigated from
organic-geochemical point of view. It is known that
vegetation is commonly identified as a significant
controlling mechanism of land degradation in
sensitive, semi-arid environments [1].
Total of 18 samples were analysed from 9 different
locations. From each location unweathered mudstone
and crust were taken. Qualitative and semiquantitative composition of the mineral part of
samples was determined using X-ray diffractometer.
Additionally, chemical properties such as pH, EC, Eh,
SAR are determined. The content of organic carbon
(Corg), was determined by elemental analysis after
removal of carbonates with diluted hydrochloric acid
(1:3, v/v). Soluble organic matter, bitumen, was
extracted from sediments using the Soxhlet extraction
with an azeotrope mixture of dichloromethan and
methanol (88:12, volume %). Isolation of the
saturated and aromatic fraction was done using
column chromatography. Organic compound were
analyzed by gas chromatography-mass spectrometry
(GC-MS) technique in the fractions of saturated
hydrocarbons.
Many study has shown that clay mineralogy is
extremely important for the behaviour of different
materials undergone weathering/erosional processes as well as smectite-containing sediments have been
shown to be more erodable [2]. Additonally, the
presence of enough amount of organic matter, iron
and aluminum oxides causes to make marls durable
while, sodium ions cause more erosion associated
with dispersed clay particles [3].
In this study, it was observed that major changes in
the distribution of saturated hydrocarbons occurred in
samples containing smectite compared to those
samples where mentioned mineral was not identified.
This confirms that the presence of smectite is crucial
factor for changes inorganic and organic matter
during erosional processes.
Mentioned changes in distribution of saturated
hydrocarbons are most pronounced for n-alkanes,
whereby higher odd-numbered n-alkanes are most
sensitive during erosive processes. For that reason
parameters which reflect the ratio of higher and lower
n-alkanes (for example, TAR, TAR/MAR, CPI)
decrease in eroded samples compared to unweathered
mudstones.
Significant changes in distribution of polycyclic
alkanes of sterane and terpane types were not
observed.",
publisher = "Lodz University of Technology",
journal = "20th European Meeting on Environmental Chemistry 2019",
title = "Distribution of saturated hydrocarbons in unweathered and erosional landforms",
pages = "116",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6162"
}
