Open AccessOrbital control on carbon cycle and oceanography in the mid‐Cretaceous greenhouse
Author(s) -
Giorgioni Martino,
Weissert Helmut,
Bernasconi Stefano M.,
Hochuli Peter A.,
Coccioni Rodolfo,
Keller Christina E.
Publication year - 2012
Publication title -
paleoceanography
Language(s) - English
Resource type - Journals
eISSN - 1944-9186
pISSN - 0883-8305
DOI - 10.1029/2011pa002163
Subject(s) - milankovitch cycles , cretaceous , orbital forcing , geology , carbon cycle , paleontology , paleoceanography , cenozoic , isotopes of carbon , cyclostratigraphy , carbon fibers , oceanography , sedimentary rock , glacial period , total organic carbon , ecology , materials science , structural basin , ecosystem , biology , composite material , composite number
We established a new high‐resolution carbonate carbon isotope record of the Albian interval of the Marne a Fucoidi Formation (Central Apennines, Italy), which was deposited on the southern margin of the western Tethys Ocean. Bulk carbonate sampled with 10–15 cm spacing was used for the construction of a continuous carbon isotope curve through the Albian stage. Spectral analyses reveal prominent 400 kyr cyclicity in the δ 13 C curve, which correlates with Milankovitch long eccentricity changes. Cycles occurring in our record resemble those observed in several Cenozoic δ 13 C records, suggesting that a link between orbital forcing and carbon cycling existed also under mid‐Cretaceous greenhouse conditions. Based on comparisons with Cenozoic eccentricity‐carbon cycle links we hypothesize that 400 kyr cycles in the mid‐Cretaceous were related to a fluctuating monsoonal regime, coupled with an unstable oceanic structure, which made the oceanic carbon reservoir sensitive to orbital variations. In the Tethys these oceanographic conditions lasted until the Late Albian, and then were replaced by a more stable circulation mode, less sensitive to orbital forcing.