USGS - science for a changing world

Pacific Coastal and Marine Science Center

Bedform Sedimentology Site: “Bedforms and Cross-Bedding in Animation”

Cross-Bedding, Bedforms, and Paleocurrents

Dip plots, static images, and captions

View Animation

Dip plot; see caption below.
Static image of cross-section; see caption below.

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.

 

Accessibility FOIA Privacy Policies and Notices

U.S. Department of the Interior | U.S. Geological Survey
URL: seds/bedforms/dip_pages/dip36.html
Page Contact Information: Web Team
Page Last Modified: 21 March 2012 (lzt)