Preliminary petrological, mineralogical, and geochemical evaluation of a newly discovered lignite field in Yatağan, Muğla (SW Türkiye)

Thirty-two coal and seven inorganic core samples from a newly discovered coalfield in the Yatağan region of the Muğla Basin were analysed to reconstruct the depositional palaeoenvironment. The coal has an average bed moisture of 34.60%, an ash yield of 33.73% (db), a volatile matter yield of 57.91% (daf), and a gross calorific value of 12.18 MJ/kg (maf). It is composed of mainly huminite macerals (up to 91 vol.%, on whole-rock basis), predominantly densinite, along small amounts of liptinite and inertinite macerals. The average random reflectance of huminite is 0.28%, and the primary minerals identified include pyrite, quartz, and clay minerals. The Yatağan coal is of low-rank C and derived from the remnants of herbaceous peat-forming plants accumulated under telmatic/limnotelmatic, rheotrophic and anoxic conditions, within a topogenous mire setting. Surface water eroded and transported inorganic material, primarily clay minerals and quartz, from the basin margins into the palaeomire. During the Early-Middle Miocene, telmatic to limnotelmatic conditions predominated in several parts of the extensive Muğla Basin, leading to the development of multiple peatlands. Subsequent coalification of these peatlands produced coal deposits with genetic characteristics comparable to those of the Yatağan deposit.