Calcareous microfossil-based orbital cyclostratigraphy in the Arctic Ocean. (1st October 2016)

• Record Type: Journal Article
• Authors: Marzen, Rachel E.; DeNinno, Lauren H.; Cronin, Thomas M.
• Is Part Of: Quaternary science reviews. Volume 149(2016)
• Page Start: 109
• Page End: 121
• Publication Date: 2016-10-01
• Subjects: Paleo-productivity -- Orbital cycles -- Arctic; Geology, Stratigraphic -- Quaternary -- Periodicals; Stratigraphie -- Quaternaire -- Périodiques; 551.79
• DOI: 10.1016/j.quascirev.2016.07.004
• Languages: English
• ISSNs: 0277-3791

Abstract

Abstract: Microfaunal and geochemical proxies from marine sediment records from central Arctic Ocean (CAO) submarine ridges suggest a close relationship over the last 550 thousand years (kyr) between orbital-scale climatic oscillations, sea-ice cover, marine biological productivity and other parameters. Multiple paleoclimate proxies record glacial to interglacial cycles. To understand the climate-cryosphere-productivity relationship, we examined the cyclostratigraphy of calcareous microfossils and constructed a composite Arctic Paleoclimate Index (API) "stack" from benthic foraminiferal and ostracode density from 14 sediment cores. Following the hypothesis that API is driven mainly by changes in sea-ice related productivity, the API stack shows the Arctic experienced a series of highly productive interglacials and interstadials every ∼20 kyr. These periods signify minimal ice shelf and sea-ice cover and maximum marine productivity. Rapid transitions in productivity are seen during shifts from interglacial to glacial climate states. Discrepancies between the Arctic API curves and various global climatic, sea-level and ice-volume curves suggest abrupt growth and decay of Arctic ice shelves related to climatic and sea level oscillations. Highlights: Analyzed cyclostratigraphy of microfossil density in central Arctic Ocean sediments. Used microfossil density as a proxy for Arctic paleoclimate over the last 550 ka. Microfossil density varies during interglacial and interstadial periods every ∼20 kyr. Results suggest strong Arctic cryosphere response to orbital cycles.