Pacific Coastal and Marine Science Center
Bedform Sedimentology Site: “Bedforms and Cross-Bedding in Animation”
FIG. 36. Structure formed by bedforms with pseudorandom plan-form geometry.
RECOGNITION: These bedforms have crestlines that are in phase at some locations and out of phase at others. The resulting structures have a more random appearance and have characteristics of both in-phase and out-of-phase bedforms (Figs. 32 and 34). The polar plot is indistinguishable from those of bed- forms with crestlines that are exactly out of phase (FIG. 34).
ORIGIN: This kind of geometry may be more common than the more regular three-dimensional geometries emphasized in this publication (Figs. 32 and 34, in particular). Figure 37 shows a real example. Irmen and Vondra (2000) described eolian sandstones that they inferred were deposited by dunes with similar geometry.