Application of sequence stratigraphy to coal-bearing coastal plain successions: implications for the UK Coal Measures

Abstract: Advances in the understanding of coal depositional environments have led to the notion that hick, low ash deposits in close proximity to siliciclastic sediment inputs are most commonly restricted to the products of raised mires. These mires are initiated, sustained and preserved in conditions of slowly rising base level (relative sea-level). H nce it is possible to consider the stratigraphic significance of economic oal seams within the concept of unconformity bounded epositional sequences ( ensu Vail et al.). Time-equivalent clastic deposits tend to be minor (commonly with a heterolith fill) channel deposits, with brackish to freshwater lake and crevasse splay sediments, excluded from the peat mire either via the topographically raised nature of the mire or by the landward islocation of fluvial facies. In this paradigm, spatially related major fluvial channel deposits, major seam splits and even washout deposits may not be time-equivalent to the coal seam. Regional correlations suggest that thick coal seams are time-correlative to significant flooding surfaces at the coeval coastline. Thus coals may be correlated with initial flooding surfaces over incised valley systems and sometimes with parasequence and parasequence s t boundaries. This factor may be important incoal exploration. Application of these ideas tothe classic Westphalia