Paleoenvironmental implications from biomarker and stable isotope investigations on the Pliocene Velenje lignite seam (Slovenia)

Petrographic and biomarker analysis of xylite-rich coal from the Kolubara and Kostolac lignite basins (Pannonian Basin, Serbia)

“…The content of total mineral matter increased in the following order: pale yellow SXC < dark yellow SXC < brown SXC < black SXC in both basins, and amount of mineral matter was almost equal in the same individual SXCs (Table 4). (Diessel 1986, adopted by Kalkreuth et al 1991 andBechtel et al 2003b); GI -Gelification Index = (Ulminite + Corpohuminite + Densinite + Gelinite) / (Textinite + Attrinite + Total inertinite) (Diessel 1986, adopted by Kalkreuth et al 1991 andBechtel et al 2003b); ΣG = Gelinite + Corpohuminite + 0.67 (Ulminite + Densinite), mineral matter-free basis (Bielowicz 2013); N.D. -Not determined, due to the absence of liptodetrinite or sporinite. This result suggests that clastic material is rather associated with black and brown than with yellow SXCs.…”

“…The change in colour of SXC from pale-and dark yellow to brown and black is followed by variations in the values of maceral indices, Tissue Preservation Index (TPI) and Gelification Index (GI) (Diessel 1986, adopted by Kalkreuth et al 1991 andBechtel et al 2003b) (Table 4). TPI decreased in order pale yellow SXC > dark yellow SXC > brown SXC > black SXC, while GI, as expected, showed the opposite trend in both basins (Table 4).…”

On the fundamental difference between coal rank and coal type

“…However, their composition provides Modified after Hatcher and Clifford (1996). information on depositional environment and changes in peat-forming vegetation (Bechtel et al, 2003(Bechtel et al, , 2008Otto and Wilde, 2001;Otto et al, 1995Otto et al, , 1997Stefanova et al, 2002). Examples of the compositional diversity of hydrocarbon composition found in subbituminous coal are shown in Fig.…”

Optical and geochemical characterization of Upper Sinemurian (Lower Jurassic) fossil wood from the Lusitanian Basin (Portugal)

“…The increase of δ 15 N in wood has been associated to N fertilization and/ or changes in drainage patterns, which are known to increase soil N dynamics and thereby increase soil, leaf, and wood δ 15 N. In addition, diagenesis and coalification also have the capability to change the original δ 15 N of fossil wood. During the initial stages of wood decomposition, the processes of mineralization (sensu Kanduč et al, 2005) and anaerobic bacteria decomposition following fungi aerobic activity are expected to occur (e.g., Bechtel et al, 2001Bechtel et al, , 2003, leaving the residual organic matter depleted in 14 N (Rimmer et al, 2006). The isotopic composition is then expected to remain stable until the onset of the bituminous stage (Boudou et al, 1984).…”

“…From the above, it seems most likely that the high δ 15 N of fossil wood samples was the result of microbial activity (see Rimmer et al, 2006) during the initial stages of wood decomposition and burial. It has been suggested that gelification and humification may be microbiologically mediated (Bechtel et al, 2001(Bechtel et al, , 2003Rimmer et al, 2006).…”