Sauropod footprints in thinly-layered sediments responsible for ‘onion-ring’ effect in broken or weathered specimens.

2013-02-20T04:45:40Z (GMT) by Tony Thulborn
<p>A, example broken obliquely, showing extent of laminations enclosing the entire footprint. B, example broken horizontally, revealing typical ‘onion-ring’ pattern of laminations surrounding the footprint.</p>