Figure 8. Portion of a Mastcam color mosaic taken on sol 2991 at the northern edge of the Sands of Forvie looking to the southeast into the sand sheet. Platy bedrock is evident in the mid-ground on the left side of the mosaic. Letters at the top of the figure denote direction. Image credit: NASA/JPL-Caltech/MSSS.
A subordinate direction is indicated by superimposed smaller ripples located in the larger ripple troughs (Figure 8). ACuriosity -based measurement campaign was conducted on the northern edge of the SoF sand deposit. Unfortunately, scoop samples were not acquired for delivery to CheMin. A left wheel scuff excavated across a transverse ripple crest and Mastcam color image data show that the surface exhibits a relatively reddish-brown color, whereas the interior contains darker sands intermixed with brighter grains (Figure 9). APXS data were acquired on four targets at the SoF measurement site: Braewick Beach, Airor, Ratharsair, and Traquir (Weitz et al., 2022). All four targets were compositionally similar, with low S, Cl, and Zn, consistent with low dust content expected on an active aeolian bedform. Grain sizes measured from MAHLI image data showed that the ripple crests contain slightly larger grains than the troughs, as is typical for the sand deposits studied by Curiosity , with evidence that the coarser grains correlate with high Ni content (Weitz et al., 2018, 2022).