The role of the Ganges-Brahmaputra mixing zone in supplying barium and [sup 226]Ra to the Bay of Bengal

Journal Article · Thu Jul 01 04:00:00 EDT 1993 · Geochimica et Cosmochimica Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(93)90287-7· OSTI ID:6282927

Carroll, J ^[1]; Falkner, K K ^[2]; Brown, E T ^[3]; Moore, W S ^[4]

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1. Univ. of South Carolina, Columbia (United States) Univ. of Alaska, Fairbanks (United States)
2. Massachusetts Inst. of Technology, Cambridge (United States) CNES, Toulouse (France)
3. Massachusetts Inst. of Technology, Cambridge (United States)
4. Univ. of South Carolina, Columbia (United States)

The Ganges-Brahmaputra river system is ranked fourth among world rivers as a source of freshwater to the oceans and is believed to supply more sediment to the ocean than any other; 1.5 [times] 10[sup 12] kg/yr (Milliman and Meade, 1983). Barium and [sup 226]Ra are typically enriched in waters where sediment-laden rivers enter the ocean. As such, the Ganges-Brahmaputra is likely to produce globally significant barium and [sup 226]Ra fluxes to the ocean. Water samples for barium and [sup 226]Ra were collected within four major channels of the Ganges-Brahmaputra mixing zone during a period of low sediment and freshwater discharge. The data suggest that in addition to suspended sediments supplied directly from rivers, river sediments deposited during high discharge in mangroves and on islands are desorbing barium and [sup 226]Ra to seawater. The release of barium and [sup 226]Ra from these sediment deposits is out-of-phase with the direct supply of sediments from the rivers. Estimates of the annual fluxes of barium and [sup 226]Ra from the Ganges-Brahmaputra mixing zone were also derived. The fluxes of barium and [sup 226]Ra are 5.3 [times] 10[sup 8] mol barium/yr and 9.5 [times] 10[sub 14] dpm radium/yr. The first silicate and phosphate mixing profiles for this system are reported. 29 refs., 6 figs., 3 tabs.

• OSTI ID: 6282927
• Journal Information: Geochimica et Cosmochimica Acta; (United States), Journal Name: Geochimica et Cosmochimica Acta; (United States) Vol. 57:13; ISSN GCACAK; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540320 -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (1990-)
540330* -- Environment
Aquatic-- Radioactive Materials Monitoring & Transport-- (1990-)
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METALS
ALPHA DECAY RADIOISOTOPES
BARIUM
CARBON 14 DECAY RADIOISOTOPES
CHEMICAL COMPOSITION
ELEMENTS
ENVIRONMENTAL TRANSPORT
EVEN-EVEN NUCLEI
GANGA RIVER
HEAVY ION DECAY RADIOISOTOPES
HEAVY NUCLEI
INDIAN OCEAN
ISOTOPES
MASS TRANSFER
METALS
MIXING
NUCLEI
RADIOISOTOPES
RADIUM 226
RADIUM ISOTOPES
RIVERS
SEAS
SEDIMENTS
STREAMS
SURFACE WATERS
YEARS LIVING RADIOISOTOPES