He became obsessed with unconformities in the rocks, where strata are distorted, rumpled or jumbled in composition, some layers of rock thrusting near vertically into those above or below. (discovermagazine.com)
The Great Unconformity — a billion years» worth of missing rock strata — could explain the origin of animal life, argue Robert Gaines and Shanan Peters (newscientist.com)
This animation shows the formation of an angular unconformity — one where the layers above and Send and receive messages absolutely for free. (myintimcity.com)