The effects of volcanic ash disturbances on a peat-forming environment; environmental disruption and taphonomic consequences

Abstract

The maceral and palynological composition of the C coal bed (Upper Cretaceous), central Utah, was significantly affected by the periodic deposition of volcanic ash in the precursor peat mire. The coal bed contains four altered volcanic ash partings (tonsteins). Sixty-seven coal and rock samples from 10 cores of the coal bed were examined for maceral composition, and 163 coal and rock samples from 10 cores were analysed for palynological composition. Abundant semifusinite (an inertinite maceral with a poorly preserved cell structure and a hight gray reflectance) is found in coal samples directly below the upper tonstein, the thickest (30-40 cm thick) of the tonstein partings