Organic petrology and organic geochemistry of selected lignites and bituminous coals from the Lena basin (Yakutia, Russia)

摘要

Lignites and bituminous coals from several deposits of one of the world's biggest coal basins, the Lena Basin, Yakutia (Russia), were studied with combined organic petrological and organic geochemical methods for the first time. The aim of this study was to characterize these coals with regard to their technological potential and environmental wholesomeness depending on their petrographical and chemical properties. Further, aspects of coal seam genesis and facies determination were points of interest. Coal seam generation took place in the Viluy syneclise and the western foredeep of the Verkhoyansk foldbelt mainly during the Upper Jurassic to the Lower Cretaceous. Most of the coals studied here are humic coals. Their rank determined by petrological (random reflectance) and chemical (TOC, CP1) parameters varies from lignite to high volatile bituminous coals. Rank increases with depth and from western to eastern direction inside the Lena basin indicating the influence of the orogenesis close to the coal deposits. Calorific values and results of the chemical analyses support the use of most of those coals, poor in ash and sulfur, for thermal conversion processes like combustion and power generation.