NOAA/WDS Paleoclimatology - Juan de Fuca Ridge Sediment Physical Property Data over the last 700,000 Years

Sedimentation near mid-ocean ridges may differ from pelagic sedimentation due to the influence of the ridges' rough topography on sediment deposition and transport. This study explores whether the near-ridge environment responds to glacial-interglacial changes in climate and oceanography. New benthic d18O, radiocarbon, multi-sensor track, and phys- ical property (sedimentation rates, density, magnetic susceptibility) data for seven cores on the Juan de Fuca Ridge pro- vide multiple records covering the past 700,000 years of oceanographic history of the Northeast Pacific Ocean. System- atic variations in sediment density and coarse fraction correspond to glacial-interglacial cycles identified in benthic d18O, and these observations may provide a framework for mapping the d18O chronostratigraphy via sediment density to other locations on the Juan de Fuca Ridge and beyond. Sedimentation rates generally range from 0.5 to 3 cm/kyr, with back- ground pelagic sedimentation rates close to 1 cm/kyr. Variability in sedimentation rates close to the ridge likely reflects remobilization of sediment caused by the high relief of the ridge bathymetry. Sedimentation patterns primarily reflect di- vergence of sedimentation rates with distance from the ridge axis and glacial-interglacial variation in sedimentation that may reflect carbonate preservation cycles as well as preferential remobilization of fine material.