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11.
Edward D. Goldberg Minoru Koide Vern Hodge A.Russel Flegal John Martin 《Estuarine, Coastal and Shelf Science》1983,16(1):69-93
The results of the U.S. Mussel Watch Monitoring Program for the period 1976–1978 for trace metals and artificial radionuclides in bivalves are presented. The substances analysed included Ag, Cu, Zn, Cd, Ni, Pb, 238Pu, 239+240Pu and 241Am. The analyses of organic substances will be presented elsewhere. The concentrations of these substances in the bivalves may reflect upwelling processes, anthropogenic inputs or natural levels. Off the California coast, mussels show markedly elevated Pu and Cd concentrations in coastal areas adjacent to the most intensive upwelling zones. Elevated levels of Pb, for example, are found in organisms living adjacent to highly urbanized places. The general patterns of distribution repeat themselves year after year at a given site. Thus, it is concluded that annual monitoring activities may not be necessary and that a frequency of sampling of several or so years may be more appropriate to identify pollution problems. Finally, national or regional baselines for metal concentrations in bivalves from unpolluted waters are proposed. National baselines for Pb in the west coast mussels of 1·0 parts 10?6 and for Ag in east coast mussels of 0·05 parts 10?6 are suggested. 相似文献
12.
The property of sphericity is used to identify some anthropogenic particles in a Lake Michigan sediment. Three classes of products from high temperature processes, primarily fossil fuel burning, have been isolated: charcoals, iron oxides and aluminosilicates. The morphologies, structures and surface characteristics are indicative of the combustion process. 相似文献
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Herbert Weiss Kathe Bertine Minoru Koide Edward D. Goldberg 《Geochimica et cosmochimica acta》1975,39(1):1-10
Chemical analyses on water from dated strata of a south Greenland permanent ice sheet revealed that there is a larger amount of sulfate in samples accumulated during the past decade than in those 60 or more years older. This increase is attributed to combustion of fossil fuel. With the exception of mercury, cadmium and possibly copper, the heavy metal distributions in the glacial waters are similar to those in atmospheric dusts. Previously reported higher mercury values in recently deposited strata were not confirmed. 相似文献
15.
Kenneth W. Bruland Minoru Koide Carl Bowser Louis J. Maher Edward D. Goldberg 《Quaternary Research》1975,5(1):89-98
Rates of sedimentation in two Lake Superior deposits were determined by both ragweed pollen and 210Pb geochronologies. The former yields an average rate over the time since the first appearance of enhanced concentrations of the pollen as a consequence of human settlement. Sedimentation rates derived on these two bases can be brought into accord if the first appearance of ragweed pollen in the sediments was around 1830 and if the sedimentation rates have been uniform over the past century. 相似文献
16.
Minoru Koide Robert Michel Edward D. Goldberg Michael M. Herron Chester C. Langway 《Earth and Planetary Science Letters》1979,44(2):205-223
The annual fluxes of artificial radionuclides (238Pu,239+240Pu,241Am,137Cs,90Sr and3H) from the atmosphere to the Ross Ice Shelf in Antarctica were determined from measurements in strata dated by210Pb. Recognizable sources include the U.S. tests (Mike-Ivy and Castle Hill) in the early 1950s, the U.S.S.R. tests of the early 1960s, the SNAP-9A burnup of 1964 and the French and Chinese tests in the late 1960s and 1970s. There are several problems still awaiting resolution: the differences in atmospheric chemistries of fission products and of transuranics produced in weapons tests and the anomalous fluxes of238Pu to the ice shelf which do not appear to reflect a one-year stratospheric residence. There is no evidence for a smearing of the fallout record as a consequence of diffusion of these radionuclides in the glacial column. 相似文献
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John F. Hoffecker Vance T. Holliday Vadim N. Stepanchuk Alexis Brugre Steven L. Forman Paul Goldberg Oleg Tubolzev Igor Pisarev 《Geoarchaeology》2014,29(1):61-77
New geoarchaeological and bioarcheological research was undertaken at the open‐air site of Mira, which is buried in deposits of the Second Terrace of the Dnepr River, roughly 15 km downstream from the city of Zaporozhye in Ukraine. Previous excavation of the site revealed two occupation layers dating to ∼32,000 cal BP. The lower layer (II/2) yielded bladelets similar to those of the early Gravettian, while the upper layer (I) contained traces of an artificial shelter and hundreds of bones and teeth of horse (Equus latipes). Mira represents the only firmly dated early Upper Paleolithic (EUP) site in the Dnepr Basin, and occupies a unique topographic setting for the EUP near the center of the broad floodplain of the Dnepr River. The site was visited during a period of floodplain stability, characterized by overbank deposition and weak soil formation under cool climate conditions. Mira was used as a long‐term camp, but also was the locus of large‐mammal carcass processing associated with a nearby kill of a group of horses (Layer I). 相似文献
20.
The problem of tracking the directions-of-arrival (DOAs) of multiple moving sonar targets with an array of passive sensors is complicated by sensor movement. An algorithm for the joint tracking of source DOAs and sensor positions is presented to address this problem. Initial maximum-likelihood estimates of source DOAs and sensor positions are refined by Kalman filtering. Spatio-temporally correlated array movement is considered. Source angle dynamics are used to achieve correct data association. The new technique is capable of performing well for the difficult cases of sources that cross in angle as well as for fully coherent sources. Computer simulations show that the approach is robust in the presence of array motion modeling uncertainty and effectively reduces dependence on expensive and possibly unreliable hardware 相似文献