Ripples

Ripples - messages from bumps

Geologists look to ancient sand ripples for clues to the environmental conditions in which they formed.
Wave-sculpted ripples form as waves travel across the surface of a body of liquid.
These waves cause water beneath the surface to circle around and around, generating oscillating flows that pick up sand grains and set them down in a process that eventually carves out troughs and grooves throughout the sandbed.



Water flows in a circular manner beneath a wave



Current direction affects the shape of the ripple

The size and spacing of wave ripples generally scale with water depth and wave conditions, and are widely used to reconstruct coastal environments of the geologic past. Interpretations based on average ripple dimensions and assumes constant wave conditions.



But many rippled beds contain striking patterns involving defects—deviations from straight, evenly spaced ripple crests—that suggest more dynamic flow regimes.

Ripple defects resembling hourglasses, zigzags, and tuning forks were likely shaped in periods of environmental changes—for instance, during strong storms, or significant changes in tidal flows.

As conditions change the ripple pattern develops defects. For example..

as waves get shorter you get narrower ripples and patterns that resemble hourglasses

as waves shorten even further—creating faster, shorter waves—produce a pattern of "secondary crests," in which existing ripples appeared to form temporary "shadow" ripples on either side, took over

on the other hand generating longer waves produces ripples in zigzag patterns

as ripples transform  to even wider spacing.patterns resembling tuning forks are created

So it would seem ripple defects are the intermediate step as the ripple pattern transform from one stable pattern to a new stable pattern. 
The area is currently under study






Learn more about WATER and ICE and OCEANS AND THEIR MARGINS and OCEAN WAVE STYLES AND PATTERNS



TOP