Variability in Late Cretaceous climate and deep waters; evidence from stable isotopes

Author(s): Li, Liangquan; Keller, Gerta
Author Affiliation(s): Primary:
Princeton University, Department of Geosciences, Princeton, NJ, United States
Volume Title: Marine Geology
Source: Marine Geology, 161(2-4), p.171-190. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0025-3227 CODEN: MAGEA6
Note: In English
Summary: Strong climatic and temperature fluctuations mark the Late Campanian and Maastrichtian as indicated by stable isotope records from the equatorial Pacific (Site 463) and middle and high latitude South Atlantic (Sites 525, 689 and 690). The first major global cooling decreased intermediate water temperatures (IWT) by 5-6°C between 73-70 Ma. At the same time, sea surface temperature (SST) decreased by 4-5°C in middle and high latitudes. Intermediate waters (IW) temporarily warmed by 2°C in low and middle latitudes between 70-68.5 Ma. Global cooling resumed between 68.5-65.5 Ma when IWT decreased by 3-4°C and SST by 5°C in middle latitudes. About 450 ka before the Cretaceous-Tertiary boundary rapid global warming increased IWT and SST by 3-4°C, though SST in the tropics changed little. During the last 200 ka of the Maastrichtian, climate cooled rapidly with IWT and SST decreasing by 2-3°C. During the global cooling at 71-70 Ma and possibly at 67-65.5 Ma, the sources of cold intermediate waters in the equatorial Pacific, Indo-Pacific and South Atlantic were derived from the high latitude North Pacific. In contrast, during the global climate warming between 65.2-65.4 Ma, the middle latitude South Atlantic was closest to the source of IW production and implies that the low latitude Tethys played a major role in global climate change. Climate changes, sea-level fluctuations and associated restricted seaways appear to be the most likely mechanisms for the alternating sources of IW production.
Year of Publication: 1999
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
ODP Ocean Drilling Program
Key Words: 02 Geochemistry; 12 Stratigraphy, Historical Geology and Paleoecology; Atlantic Ocean; Campanian; Climate change; Cores; Cretaceous; DSDP Site 463; DSDP Site 525; Deep Sea Drilling Project; Deep-water environment; Depositional environment; Equatorial Pacific; Geochemistry; IPOD; Isotopes; Leg 113; Leg 62; Leg 74; Maestrichtian; Marine environment; Mesozoic; ODP Site 689; ODP Site 690; Ocean Drilling Program; Pacific Ocean; Paleoclimatology; Paleoenvironment; Sea-level changes; Sea-surface temperature; Senonian; South Atlantic; Stable isotopes; Upper Campanian; Upper Cretaceous
Coordinates: N212101 N212101 E1744004 E1744004
S290415 S290414 E0025908 E0025907
S643101 S643100 E0030600 E0030559
S650938 S650937 E0011218 E0011218
Record ID: 1999055463
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands