Sigurdsson, Haraldur and Leckie, R. Mark (1996): Leg 165 scientific prospectus; Caribbean ocean history and Cretaceous/Tertiary boundary event

ODP 165


Sigurdsson, Haraldur
University of Rhode Island, Graduate School of Oceanography, Narragansett, RI, United States

Leckie, R. Mark
University of Massachusetts at Amherst, United States

Leg 165 scientific prospectus; Caribbean ocean history and Cretaceous/Tertiary boundary event
Scientific Prospectus
Ocean Drilling Program, Texas A&M University, College Station, TX, United States
114 pp.
The Caribbean region presents a wide array of geologic problems related to its plate tectonic evolution, the nature of its oceanic crust or basement, ocean and climate history, and the opening and closing of intra-Caribbean and Atlantic-to-Pacific seaways. With the exception of DSDP Site 502, the Caribbean has not been targeted by the Ocean Drilling Program or Deep Sea Drilling Project for more than two decades. A fresh impetus has now been given to Caribbean drilling by the recent discovery of a strewn field of unaltered impact glass spherules or tektites in Haiti and Mexico at the Cretaceous/Tertiary boundary, and the identification of their source in the 180 to 300 km-wide Chicxulub impact crater in the Yucatan. Leg 165 drilling will address two major themes: the nature of the Cretaceous/Tertiary boundary and the influence of tropical seas on global ocean history and climate evolution. Drilling at five primary sites will provide a unique opportunity to examine nearly 90 m.y. of Earth history, including (1) the K/T boundary impact event, mechanisms of ejecta dispersal, and environmental consequences from aerosols and fallout of ejecta; (2) catastrophic extinction events and biotic recovery; (3) the nature of climate forcing in the pre-Neogene world and tests of climate models with boundary conditions very different from those of today; (4) several episodes of moderate to extreme climatic warmth (early Late Cretaceous, early Eocene, early to mid Pliocene); (5) the evolution of tropical sea surface temperatures and changes in meridional temperature gradients; (6) changes in oceanic circulation and in sources of deep and intermediate water masses through Late Cretaceous and Cenozoic time; (7) the closing of low latitude oceanic gateways, the opening of a major gateway within the Caribbean, and the oceanic and climatic consequences of low latitude tectonics during the late Neogene; (8) tropical climate variability during the late Quaternary; and (9) nature and origin of Caribbean crust.
Coverage:Geographic coordinates:
West:-83.0000East: -65.0000

Stratigraphy; Atlantic Ocean; Caribbean Sea; Cenozoic; Chicxulub Crater; cores; Cretaceous; K-T boundary; Leg 165; lower Paleocene; Mesozoic; North Atlantic; ocean circulation; Ocean Drilling Program; ocean floors; paleo-oceanography; Paleocene; paleoclimatology; paleoenvironment; Paleogene; paleotemperature; plate tectonics; stratigraphic boundary; Tertiary; Upper Cretaceous;