Mercury Concentrations in Dated Varved Marine Sediments collected off Southern California

摘要: ANNOUNCEMENTS that mercury concentrations often exceed recommended limits in some oceanic fishes, such as swordfish and tuna, have suggested the possibility man has polluted ocean with on a massive scale1. Although there are examples of localized pollution certain fresh coastal waters2–4, few data historical levels this metal marine environment distant from specific inputs wastewater outfalls. Here we report observed dated varved sediment layers Santa Barbara Basin covering past 150 yr, well two estimated to been deposited approximately 1,500 yr BP. This basin is 100 mile northwest Los Angeles, sufficiently removed densely populated areas be protected concentrated effects pollutant inputs. The record investigated includes before beginning California mining activity 1849. Thus, it possible compare near surface those could released significant amounts directly into Current.