TY - JOUR
T1 - A perturbed hydrological cycle during Oceanic Anoxic Event 2
AU - van Helmond, N.A.G.M.
AU - Sluijs, A.
AU - Reichart, G.-J.
AU - Sinninghe Damsté, J.S.
AU - Slomp, C.P.
AU - Brinkhuis, H.
PY - 2014
Y1 - 2014
N2 - The Late Cretaceous Oceanic Anoxic Event 2 (OAE2; ca. 94 Ma) was one of the largest global carbon cycle perturbations during the Phanerozoic. OAE2 represents an important, although extreme, case study for modern trends because widespread anoxia and enhanced organic carbon burial during OAE2 were linked to exceptionally warm climates and high atmospheric CO2 concentrations. However, the consequences of this warmth for the hydrological cycle remain poorly understood, hampering our understanding of its impact on biogeochemical cycles during this greenhouse episode. Here we show evidence for changes in the hydrological cycle during OAE2 based on combined geochemical and palynological data for the stratigraphically expanded coastal OAE2 succession at Bass River, located on the New Jersey shelf (Ocean Drilling Program Leg 174AX), eastern United States. Paleothermometry, based on TEX86, indicates sea-surface warming at the onset of OAE2 and a subsequent pronounced cooling event. Palynological data show that these changes in temperature were associated with strong variations in precipitation and runoff. We suggest that an acceleration of the hydrological cycle during OAE2 played a key role in supplying nutrients to coastal waters and enhancing stratification, thus contributing to the development of ocean anoxia.
AB - The Late Cretaceous Oceanic Anoxic Event 2 (OAE2; ca. 94 Ma) was one of the largest global carbon cycle perturbations during the Phanerozoic. OAE2 represents an important, although extreme, case study for modern trends because widespread anoxia and enhanced organic carbon burial during OAE2 were linked to exceptionally warm climates and high atmospheric CO2 concentrations. However, the consequences of this warmth for the hydrological cycle remain poorly understood, hampering our understanding of its impact on biogeochemical cycles during this greenhouse episode. Here we show evidence for changes in the hydrological cycle during OAE2 based on combined geochemical and palynological data for the stratigraphically expanded coastal OAE2 succession at Bass River, located on the New Jersey shelf (Ocean Drilling Program Leg 174AX), eastern United States. Paleothermometry, based on TEX86, indicates sea-surface warming at the onset of OAE2 and a subsequent pronounced cooling event. Palynological data show that these changes in temperature were associated with strong variations in precipitation and runoff. We suggest that an acceleration of the hydrological cycle during OAE2 played a key role in supplying nutrients to coastal waters and enhancing stratification, thus contributing to the development of ocean anoxia.
U2 - 10.1130/G34929.1
DO - 10.1130/G34929.1
M3 - Article
SN - 0091-7613
VL - 42
SP - 123
EP - 126
JO - Geology
JF - Geology
IS - 2
ER -