Millennial–scale CaCO₃ and C[subscript ORG] events along the northern and central California margins : stratigraphy and origins

• Main Authors: Lyle, Mitchell, Mix, Alan C., Ravelo, A. Christina, Andreasen, Dyke, Heusser, Linda, Olivarez, Annette
• Format: Article in Journal/Newspaper
• Language: English; unknown
• Published: College Station, Tex. : Ocean Drilling Program, Texas A & M University
• Subjects: Pacific; North Atlantic
• Online Access: https://ir.library.oregonstate.edu/concern/articles/dz010v603

Sediments from five Leg 167 drill sites and three piston cores were analyzed for C[subscript ORG] and CaCO₃. Oxygen isotope stratigraphy on benthic foraminifers was used to assign age models to these sedimentary records. We find that the northern and central California margin is characterized by k.y.-scale events that can be found in both the CaCO₃ and C[subscript ORG] time series. We show that the CaCO₃ events are caused by changes in CaCO₃ production by plankton, not by dissolution. We also show that these CaCO₃ events occur in marine isotope Stages (MIS) 2, 3, and 4 during Dansgaard/Oeschger interstadials. They occur most strongly, however, on the MIS 5/4 glaciation and MIS 2/1 deglaciation. We believe that the link between the northeastern Pacific Ocean and North Atlantic is primarily transmitted by the atmosphere, not the ocean. Highest CaCO₃ production and burial occurs when the surface ocean is somewhat cooler than the modern ocean, and the surface mixed layer is somewhat more stable.