Why are Anklyosaur Fossils Found in Marine Deposits?

Ankylosaurs, like probably most other dinosaurs, were landlubbing, terrestrial animals without obvious aquatic adaptations. And yet, surprisingly, their fossils are found in marine sedimentary environments more often than most other dinosaurs (except hadrosaurs). Some, like Aletopelta, wound up in shallow or lagoonal environments - Aletopelta's carcass became a reef! - but some, like the Suncor nodosaurid, wound up far away from shore.

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