Table 1.

Fogo member A isopach map of Walker and Croasdale (1971): Comparison of differences between measured thicknesses and spline interpolation of published isopachs; mean and standard deviation of percentage differences for distributions shown in Fig. 2 (first row)

	Mean %	Standard deviation of %
Measured thickness vs. thickness from isopach map interpolation difference	64	95.8
Measurement error	16.2	29.8
Exponential regression fit difference	90.4	143.8
Power law regression fit difference	83	128.1

Other rows: calculated measurement error and percentage differences between exponential and power law regression fits to thickness with distance (from Engwell et al. 2013)