Abstract

R. B. Ainsworth writes: Richardson & Rasul (1990) attempt to compare the depositional environments inferred from their palynofacies analyses of the Upper Whitcliffe Formation and Downton Castle Sandstone Formation ‘with those proposed previously from sedimentological data’. However, more recent sedimentological data than that used by Richardson & Rasul (1990), and regional geological evidence, can be utilized to explain more fully the patterns and trends of inshore and marine influence indices shown by the palynofacies curves in their paper.

Sedimentology of the Upper Whitcliffe and Downton Castle Sandstone Formations. Richardson & Rasul (1990) correctly point out that work by Muller (1959) indicates that oceanic currents, the prevailing wind, and land and marine physiography may modify the general pattern of decreased abundance of land-derived palynomorphs in an offshore direction. However, they fail to consider some of these potential modifications in their study. The storm-dominated nature of the Downton Castle Sandstone Formation in the Ludlow area has been documented by Smith & Ainsworth (1989; published after the acceptance of Richardson & Rasul 1990), who described amalgamated hummocky cross-stratification, thinly bedded fining-upwards siltstone beds with basal lags of skeletal sand, wave ripple cross-lamination and gutter casts from the Ludford Lane locality. Allen (19856, p. 90) described ‘storm-related planar to hummocky lamination, cross-lamination and wave- current ripples’ from the Upper Whitcliffe Formation. Watkins (1979) also discussed the storm signature of Ludlow strata in the Welsh borders. Therefore, due to the storm-dominated nature of the whole succession, extreme caution should be exercised when interpreting any palynological

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