title: High activity concentrations of (210)Pb and (7)Be in sediments and their histories.
abstract: High activity concentrations of (210)Pb and (7)Be, in addition to (137)Cs, were found in a rooftop deposit in Japan. This deposit had activities of about 5 Bq/g from (210)Pb and 3.6 Bq/g from (7)Be, an order of magnitude greater than typically found in field soils and lake and sea bottom sediments. It is clear that under certain conditions aerosol particles can accumulate in deposits with little or no mixing and dilution by silicate materials, and that subsequent processes and factors result in a heterogeneous distribution pattern of activity concentration on the Earth's surface. A simple model suggests that the history of an environmental sample can be estimated by using the activities of (210)Pb and (7)Be.
authors: Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567, Japan. y.kanai@aist.go.jp
authors: Yutaka
authors: Y
authors: Kanai
mesh_terms: D001608:Beryllium / Q000032:analysis*; D062406:Fukushima Nuclear Accident; D019015:Geologic Sediments / Q000032:analysis; D007564:Japan; D007856:Lead Radioisotopes / Q000032:analysis*; D011834:Radiation Monitoring; D011868:Radioisotopes / Q000032:analysis*; D012987:Soil / Q000032:analysis; D012990:Soil Pollutants, Radioactive / Q000032:analysis*
chemical_list: D007856:Lead Radioisotopes; D011868:Radioisotopes; D012987:Soil; D012990:Soil Pollutants, Radioactive; D001608:Beryllium
keywords: (210)Pb; (7)Be; Activity concentration; Sediment