*4.4. Comparative Variation in Clast Shapes*

Raw data on clast size in three dimensions collected from each of the three sample sites are shown in Appendix A (Tables A1–A3). With regard to shape, points representing individual cobbles and boulders are fitted to a set of Sneed–Folk triangular diagrams (Figure 8a–c). The spread of points across these plots consistently shows a strong similarity in the variation of shapes from one sample to another. Few points fall into the upper-most triangle, which represents an origin from a perfectly cube-shaped endpoint as a joint-bound block. The majority of points in each sample fall within the middle part of the two tiers below the top triangle. Those points clustered at the core of any given triangular plot are representative of clasts for which two of the three dimensions are close in value. Relatively few points fall into the middle-right and lower-right domains of the field, which signify a tendency toward development of elongated shapes eroded from source rock exposed in sea cliffs. The composite slope of points suggests a diagonal trend in orientation, although the majority of points cluster vertically within the two central boxes. There is a total absence of points plotting within the left side and lower left part of the plots. The overall aspect of distributed points in these plots signifies the rounding of clasts in which two of the dimensions (preferentially the maximum and intermediate lengths) are closely matched.

**Figure 8.** Set of triangular Sneed–Folk diagrams used to appraise variations in cobble and boulder shapes: (**a**) trend from sample 1 on the SW flank of Støypet, (**b**) trend sample 2 at the top, and (**c**) Trend from sample 3 on the NE flank of Støypet.

#### *4.5. Comparative Variation in Clast Sizes*

Clast size is conveniently plotted on bar graphs as a function of maximum and minimum length drawn from the original data (Tables A1–A3). The results for each of three field samples are paired according to size intervals at 5-cm intervals with the boundary between large cobbles and small boulders clearly marked at a diameter above 25 cm (Figure 7). The field locality for sample 1 sits below the crest of the pass between Steinstind and Hagafjellet on the SW side of Støypet valley about 75 m above sea level (Figure 4). The ratio of cobbles to boulders from the sample drawing on maximum clast length is 2:3 (Figure 9a). An equal number of large cobbles and small boulders plot adjacent to one another in bins at the definitional boundary, but the plot is skewed with two individual boulders having a maximum length between 41 and 50 cm. The general shape of clasts from this sample is demonstrated by comparison with the plot for minimum length in which the majority of clasts align below the boundary between cobbles and boulders (Figure 9b). The field locality for sample 2 occurs at the top of the pass between Steinstind and Hagafjellet at the midpoint of Støypet valley just below 100 m in altitude (Figures 4 and 5). Drawing on data for maximum clast length (Table A2), the ratio of large cobbles to small boulders is 1:7 (Figure 9c), which is significantly different from the example in sample 1 (Figure 9a). The number of clasts that plot adjacent to one another in bins at the definitional boundary are sharply divergent, with small boulders outnumbering large cobbles by more than 3 to 1. The graphs for maximum clast length in Figure 9a, c are more alike with respect to outliers of boulders having a maximum length between 41 and 50 cm. With regard to the range in clast sizes drawn from the short axis, sample 2 includes no boulders at all (Figure 9d), which is a departure from sample 1 in this regard (Figure 9b).

**Figure 9.** Set of bar graphs used to contrast variations in maximum and minimum clast length from three samples in Støypet valley: (**a**,**b**) bar graphs from Locality 1 on the SW flank of the deposit, (**c**,**d**) bar graphs from Locality 2 at the top of Støypet, and (**e**,**f**) bar graphs from Locality 3 on the NE flank of the deposit. Dashed line (offset to represent 26.6 mm) marks the boundary between large cobbles and small boulders.

Like the field locality for sample 1, sample 3 sits at an elevation about 75 m above sea level but on the opposite NE side of Støypet valley below the crest of the pass (Figure 4). Based on data for maximum clast length in this sample (Table A3), the ratio of cobbles to boulders is more balanced, but the quantity of boulders outnumbers that for cobbles and the ratio between large cobbles and boulders in adjacent bins is 1:2 (Figure 9e). There exist fewer outliers of larger boulders in this sample

compared to samples 1 and 2 and the number of smaller cobbles in the opposite extreme also exceeds that found in samples 1 and 2 (compared Figure 9a,c,e). Data plotted in bar graphs on the basis of the shortest axis on clasts from sample 3 not only lack boulders but also the class of largest cobbles in size between 21 and 25 cm. In total (Figure 9), the side-by-side plots for sample 3 exhibit a marked downward shift in clast size compared to those from samples 1 and 2.
