Quaternary glacial/interglacial changes in the carbonate compensation depth (CCD) have been determined from core suites in three regions of the NE Pacific. The cores have sedimentation rates ranging from 1.6 to 16 cm/kyr, based on oxygen isotope, radiocarbon, and/or carbonate stratigraphies. Carbonate values are higher in glacial than interglacial times and generally follow a pattern similar to that of the central equatorial Pacific. The sediment's carbonate profiles can be readily intercorrelated, allowing the construction of a regional carbonate stratigraphy. The extent of carbonate preservation is very sensitive to small changes in water depth but does not depend on geographic location. A depth transect of cores off northern California and Oregon provides a detailed record of glacial/interglacial shifts in the CCD through time. During the late Holocene, intensified carbonate dissolution at ∼7 ka is coincident with shifts in continental climatic indicators and may suggest the onset of the modern upwelling regime along the NW U.S. margin. During the last 45 ka the CCD has migrated more than 1800 m between glacial and interglacial times. Although carbonate patterns are similar to those in the equatorial Pacific, the amplitude of the carbonate fluctuations is much greater in the northeast Pacific. This suggests that regional mechanisms, such as glacial deepwater formation or enhanced dissolution due to interglacial noncarbonate productivity related to coastal upwelling, may modulate carbon cyclin
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