Introduction

Research by Fisher and McGowen (1967) on the stratigraphy and sedimentology of the upper Paleocene part of the Wilcox Group in the Gulf Coast Basin in Texas (Fig. 12.1C) resulted in the definition of seven ancient depositional systems in the outcropping and subsurface Wilcox. Coal-forming peat had accumulated within four of them. Traverse and Nichols (1967), Nichols (1970), and Nichols and Traverse (1971) identified paleoecologically significant groups of palynomorphs within assemblages from outcropping Wilcox coal beds in an effort to distinguish palynologically the interrelated but differing depositional systems defined by Fisher and McGowen.

In the Powder River Basin of Montana and Wyoming (Fig. 12.IB), studies on lower Tertiary coal deposits of the Fort Union Formation by Flores (1981,1983), Flores and Hanley (1984), and Hanley and Flores (1987) provided a similar stratigraphic and sedimentologic framework for palynological studies. Depositional models for coal formation in this region were proposed by Pocknall (1986a) and Pocknall and Flores (1987); see also Satchell (1984; 1985). As in the Gulf Coast study, an aspect of research on Powder River Basin coal beds was the identification of groups of palynomorphs that represent the depositional environments.

In this chapter we expand upon the interpretations of Nichols and Traverse (1971) for upper Paleocene coal beds of the Gulf Coast Basin and compare them with those obtained by Pocknall and Flores (1987) for upper Paleocene coal beds in the Powder River Basin. We use palynofacies to characterize and contrast coal-depositional environments within these regions.