Summary: | Water samples were collected from Baffin Bay and surrounding areas in order to evaluate this region as a potential source of Nd from old continental material to Atlantic water. The isotopic data ranged from ε_(Nd)(0) = −9.0 to −26 with most of the data around ε_(Nd)(0) = −20 compared with values of North Atlantic Deep Water (NADW) with ε_(Nd)(0) = −13.5. The concentration of Nd in Baffin Bay waters was as high as 6 × 10^(−12) g/g compared with 2.5 × 10^(−12) g/g for NADW. The combination of low ε_(Nd) and high Nd concentration indicates that Baffin Bay may be a significant source of Nd from very old crustal material. A simple box model was used to evaluate the contribution to the Nd budget of NADW and it was concluded that a substantial fraction of the Nd from ancient crustal sources that is required to maintain the isotopic composition of NADW could be supplied by Baffin Bay outflow. © 1986 Elsevier Science. Received September 17, 1985; revised version received January 20, 1986. We thank T. Platt for allowing M.C. Stordal to participate on the cruise of the Canadian research vessel C.S.S. "Hudson". The assistance of the crew of the C.S.S. "Hudson" and the hospitality of the staff was greatly appreciated. E. Horne and D. Wallace also assisted in gathering of T-S data. The Mississippi samples were collected on the 1982 cruise of the Gyre under the direction of Dr. Martha Scott, Department of Oceanography, Texas A&M. Her support and guidance are greatly appreciated. The Amazon samples were collected by Barry Grant on cruise TTO-TAS, Leg 1. We thank H. Ngo for analyzing the duplicate sample. The authors are particularly indebted to F. Begemann (editor) and A. Hoffman, reviewer for this journal. They have considered this manuscript for publication after it was twice rejected by another journal. This research was supported by grant NSF OCE 8320516. This is contribution #4158 (490) of the Division of Geological and Planetary Sciences, California Institute of Technology.
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