Akademik Veri Yönetim Sistemi
3rd International Conference on Frontiers in Academic Research, Konya, Türkiye, 15 - 16 Haziran 2024, ss.182, (Özet Bildiri)
Abstract – The extensional tectonic regime in western Anatolia
during the Miocene caused the formation of E-W and NE-SW trending graben basins
and volcanic activities. Furthermore, optimal climatic conditions and
subsidence rates allowed the formation of peat mines during this period. Hence,
volcanic rocks and economic coal seam-bearing fluviolacustrine sequences
comprise basinal infillings of graben basins in western Anatolia. The Uşak-Güre
Basin is a good example of the NE-SW trending basin in western Anatolia, which
was controlled by faults developed in three deformation phases between the
Early and Late Miocene. A mineable coal seam with a cumulative thickness of
2.22 m is located in the late Early-Middle Miocene Küçükderbent Formation,
which is exploited in the İlyaslı coalfield in the central parts of the basin.
This seam also contains several clayey intercalations and altered tuff layers.
Previous palynological studies indicated that the precursor peat of the seam
was accumulated during the early Middle Miocene. Furthermore, Early-Middle
Miocene Beydağı Volcanics are widely cropped out in the eastern margins of the
İlyaslı coalfield. The studied samples are generally black in colour, and
matrix lithotype is commonly identified. The coal samples on an air-dry basis
display low moisture contents (avg. 7.6%), low to moderate ash yields (avg.
17.2%), high gross calorific values (avg. 4408 kcal/kg), and low total S
contents (avg. 1.8%). The coal petrography analysis shows that telohuminite is
the predominant maceral group in the samples, while liptinite and inertinite
proportions are slightly low. The random huminite reflectance (%Rr) values are
between 0.40 and 0.41%±0.01. Considering %Rr values along with gross calorific
values and ash yields, the samples are medium-grade sub-bituminous (low-rank A)
coal. The coal facies indices imply that the peat surface was covered by mainly
woody peat-forming plants, while the contribution of herbaceous peat-forming
plants was increased during the late stages of peat accumulation. Moreover, the
coal facies data agrees with the published paleobotanic and palynological data.
The relatively low to moderate ash yields of samples and the common presence of
framboidal pyrite grains could be indicators of a low clastic influx ratio and
anoxic conditions within the palaeomires. Overall, the precursor peat mires of
the studied coal seam seemed to have been developed when the basin geometry was
half-graben during the late Early to early Middle Miocene.
Keywords – Uşak-Güre Basin, Miocene, Hacıbekir group, Peat-forming environment