Molecular indicators for coal-forming palaeoplant community. "Katrishte" Coal deposit

Coal deposit "Katrishte" located in south-western Bulgaria, Ro = 0.34%, was subjected to geochemical study. By chromatographic and spectral methods, a variety of coal biomarkers in bitumen extract has been revealed. n-Alkane distribution pattern indicated at least two possible sources, lacustrine and terrestrial ones. The aliphatic fraction was strongly dominated by 16a(H)-kaurane and 16a(H)-phyllocladane, a proof for the presence of Pinales in coal-forming palaeoplant community. The kaurane prevalence over phyllocladane could indicate the herbaceous flowering plant contribution. The combination of sesquiterpenoids/diterpenoids pointed to Pinaceae and Araucariceae.As a biomarker assemblage peculiarity, the lack of isoprenoids, tricyclic diterpenoids, and pentacyclic triterpenoids could be indicated.Our data gave us ground to assume existence of bush moor with the presence of herbaceous flowering plants, and subordinate contributions of conifers and sedge-reeds to coal forming plant taxa of "Katrishte