Transport and sediment accumulation of sup 210 Pb and sup 137 Cs in two southeast Alaskan fjords

Journal Article · Wed May 01 00:00:00 EDT 1991 · Estuaries; (United States)

OSTI ID:5142251

Sugai, S F ^[1]

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1. Univ. of Alaska, Fairbanks (United States)

Sediment profiles of {sup 210}Pb and {sup 137}Cs in cores collected at increasing distances form the heads of Smeaton Bay and Boca de Quadra fjords indicate that watersheds influence the inventories of radioisotopes present and that the steep topographies of the fjords enhance sediment redistribution. Episodic deposition of terrestrially derived sediment was responsible for roughly 50% of the {sup 137}Cs and 45% of the {sup 210}Pb inventories in shallower (less than 180 m) locations in Wilson and Bakewell arms of Smeaton Bay. {sup 210}Pb sedimentation rates at shallower sites when corrected for episodic deposition were less than sedimentation rates obtained in the deep basins of the fjords where sediment focusing and increased primary productivity in the overlaying water column occur. Higher fluxes of dissolved Mn from surficial sediments and subsequent reoxidation in the overlying water may have enhanced scavenging of {sup 210}Pb in basin locatons resulting in higher inventories. Episodic events have occured frequently in Smeaton Bay and Boca de Quadra suggesting that steady-state conditions with respect to sedimenting particles can be achieved only when averaged over long time periods approaching the time over which {sup 137}Cs and {sup 210}Pb are useful.

• OSTI ID: 5142251
• Journal Information: Estuaries; (United States), Vol. 41:5; ISSN 0160-8347
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
CESIUM 137
ENVIRONMENTAL TRANSPORT
ESTUARIES
SEDIMENTATION
LEAD 210
ALASKA
BIOGEOCHEMISTRY
MANGANESE
PRODUCTIVITY
RADIOECOLOGICAL CONCENTRATION
SEDIMENTS
ALKALI METAL ISOTOPES
ALPHA DECAY RADIOISOTOPES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CESIUM ISOTOPES
CHEMISTRY
DEVELOPED COUNTRIES
ECOLOGICAL CONCENTRATION
ELEMENTS
EVEN-EVEN NUCLEI
FEDERAL REGION X
GEOCHEMISTRY
HEAVY NUCLEI
INTERMEDIATE MASS NUCLEI
ISOTOPES
LEAD ISOTOPES
MASS TRANSFER
METALS
NORTH AMERICA
NUCLEI
ODD-EVEN NUCLEI
RADIOISOTOPES
SURFACE WATERS
TRANSITION ELEMENTS
USA
YEARS LIVING RADIOISOTOPES
540330* - Environment
Aquatic- Radioactive Materials Monitoring & Transport- (1990-)