title: Episodic ice-free arctic ocean in pliocene and pleistocene time: calcareous nannofossil evidence.
abstract: Today's ice cover (2 to 4 meters thick) over the Arctic Ocean provides a shadow that prevents coccolithophorids (photosynthetic, planktonic algae) from living there. Sparse, low-diversity, but indigenous coccolith assemblages in late Pliocene to mid-Pleistocene (but not Holocene) sediments imply deep penetrating warm currents or an ice-free Arctic Ocean, or both, as those layers were being deposited.
authors.forename: T R
authors.initials: TR
authors.lastname: Worsley
authors.forename: Y
authors.initials: Y
authors.lastname: Herman