Middle–Late Cretaceous climate of the southern high latitudes: Stable isotopic evidence for minimal equator-to-pole thermal gradients

Abstract

A detailed 8^*0 and 8"C stratigraphy has been generated from analysis of well-preserved Albian-early Maastrichtian foraminifera from Deep Sea Drilling Project (DSDP) Sites 511 and 327 (Falldand Plateau;-58°S-62°S paleolatitude) in the southern South Atlantic, and Cenomanian and Coniacian-Santonian foraminifera from DSDP Site 258 (Naturaliste Plateau; «»58°S paleolatitude) in the southern Indian Ocean. These results, when combined with previously published Maastrichtian stable isotope data from Ocean Drilling Program (ODP) Site 690 (Weddell Sea, '»65°S paleolatitude), provide new insight into the climatic and oceanographic history of the southern high latitudes during middle-Late Cretaceous time. The planktonic foraminifer S^^O curves reveal a gradual warming of surface waters from the Albian through the Cenomanian followed by extremely warm surface waters from the Turonian through the early Campanian. Long-term cooling of surface waters began in the late early Campanian and continued through the end of the Maastrichtian. The benthic foraminifer 8^*0 record generally parallels changes in the oxygen isotopic curves defined by shallow-dwelling planktonic foraminifera. The vertical oxygen and carbon isotopic gradients were relatively low during the Albian-Cenomanian, high from the Turonian-early Campanian, and then low during the late Campanian and Maastrichtian. Foraminiferal oxygen isotopic data from published sources and this study are averaged for each site, corrected for latitudinal changes in salinity based on modern-day surface-water values, and plotted versus paleolatitude for the late Albian, Coniacian-Santonian, and late Maastrichtian. Differences between low-and highlatitude surface-water paleotemperatures are estimated at "^14 °C during the late Albian and late Maastrichtian, but the Coniacian-Santonian reconstruction reveals only a 0-4 °C latitudinal temperature gradient. Uncertainty regarding Cretaceous salinity gradients and possible diagenetic alteration of 8'*0 values introduce error into our estimates of paleolatitudinal thermal gradients; however, apparent low equator-to-pole temperature differences could indicate much higher poleward heat transport than at present.

A multi-proxy approach to determine Antarctic terrestrial palaeoclimate during the Late Cretaceous and Early Tertiary

“…The data coverage compared with other regions of the southern hemisphere is relatively sparse, but indicates relatively cool Aptian-Albian marine temperatures followed by a warming into the Coniacian-Early Campanian. The lack of data from the Cenomanian to Turonian is problematic as peak temperatures are seen in this interval elsewhere in southern high latitudes (Huber et al, 1995). However, late Albian to late Turonian strata of the Whisky Bay Fm (Riding and Crame, 2002) contain elements of a re-worked shallow-water marine fauna with probable Tethyan affinities.…”

“…Cooling of the surface waters began in the late Early Campanian and continued through to the end of the Maastrichtian (Huber et al, 1995;Abreu et al, 1998). Global curves also show a cooling trend in the Late Maastrichtian (Huber, 1998).…”

Changes in paleo-circulation and the distribution of ammonite faunas at the Coniacian–Santonian transition in central Poland and western Ukraine

“…As they noted, their reference curve is remarkably similar in shape to published, supposedly eustatic, sealevel curves with increasing δ 13 C values accompanying sea-level rise and transgression, and falling δ 13 C values characterizing sea-level fall and regression. Although an increasing number of Coniacian-Santonian (mid-Upper Cretaceous) sedimentary sections around the world have been investigated by means of stable isotope geochemistry (Coplen and Schlanger 1973;Arthur et al 1985;Jenkyns et al 1994;Huber et al 1995;Gruszczyński et al 2002;Zapata et al 2003;Leckie et al 2005;Jacobs et al 2005;Li et al 2006;Jarvis et al 2006;Lamolda and Paul 2007;Gale et al 2007), detailed correlation of stable isotope curves for the Coniacian-Santonian boundary interval, is less clear-cut than for other Upper Cretaceous intervals (Jarvis et al 2006).…”

Precipitation rates and atmospheric heat transport during the Cenomanian greenhouse warming in North America: Estimates from a stable isotope mass-balance model

“…Quantifying global transfers of sensible heat by the oceans (Covey and Barron, 1988;Crowley, 1991;Barron et al, 1995;Sloan et al, 1995) and latent heat by the atmosphere are necessary to explain warmer polar temperatures (Parrish and Spicer, 1988a, b) during greenhouse periods of Earth history (Schneider et al, 1985;Huber et al, 1995;Upchurch et al, 1999). Increased global temperatures increase the saturation vapor pressure of the troposphere, and modify latent heat transfer from low to high latitudes .…”