bomb sag

bomb sag

[′bäm ‚sag]
(geology)
Depressed and deranged laminae mainly found in beds of fine-grained ash or tuff around an included volcanic bomb or block which fell on and became buried in the deposit.
References in periodicals archive ?
Dufek and his collaborators at the University of California-Berkeley received enough data to determine the size, depth and shape of the bomb sag.
The team propelled particles of varying materials (glass, rock and steel) at different speeds into dry, damp and saturated sand beds before comparing the divots with the bomb sag on Mars.
No matter the type of particle, the saturated beds consistently produced impact craters similar in shape to the Martian bomb sag.