Reconstructing a 180 yr record of natural and anthropogenic induced low-oxygen conditions from Louisiana continental shelf sediments

  title={Reconstructing a 180 yr record of natural and anthropogenic induced low-oxygen conditions from Louisiana continental shelf sediments},
  author={L. Osterman and R. Poore and P. Swarzenski and R. E. Turner},
Hypoxia on the Louisiana continental shelf is tied to nutrient loading and freshwater stratification from the Mississippi River. Variations in the relative abundance of low-oxygen-tolerant benthic foraminifers in four sediment cores from the Louisiana shelf provide a proxy record of low-oxygen events. Core chronologies are obtained using 2 1 0 Pb dating techniques. The foraminiferal data are consistent with previous studies indicating that the intensity of hypoxic events (oxygen <2 mg/L) has… Expand

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