URANIUM GEOCHEMISTRY IN ESTUARINE SEDIMENTS - CONTROLS ON REMOVAL AND RELEASE PROCESSES

被引:147
作者
BARNES, CE [1 ]
COCHRAN, JK [1 ]
机构
[1] SUNY STONY BROOK,MARINE SCI RES CTR,STONY BROOK,NY 11794
关键词
D O I
10.1016/0016-7037(93)90367-6
中图分类号
P3 [地球物理学]; P59 [地球化学];
学科分类号
0708 ; 070902 ;
摘要
Porewater uranium profiles from Long Island Sound (LIS) and Amazon shelf sediments and LIS sediment incubation experiments indicate that both removal and release processes control U geochemistry in estuarine sediments. Release of U from sediments occurs in association with Fe reduction. A correlation between U and Fe (and Mn) observed in sediment incubation experiments suggests that there is release of U from Fe-Mn-oxides as they are reduced, consistent with data from the Amazon shelf. In both sediment porewater profiles (LIS and Amazon) and sediment incubation experiments (LIS), there is removal of U from porewater under conditions of sulfate reduction. Sediment incubation experiments indicate that the removal rate is first-order with respect to U concentration, and the rate constant is linearly correlated to sulfate reduction rates. The link between U removal and sulfate reduction (a measure of diagenetic microbial activity) is consistent with a microbial mediation of U reduction. The diffusional flux of U into LIS sediments is estimated from porewater profiles. The inclusion of this. estuarine removal term in the oceanic U balance increases the importance of the sediment sink.
引用
收藏
页码:555 / 569
页数:15
相关论文
共 50 条
[1]  
ALGEO TJ, 1980, ADV GEOPHYS, V22, P351, DOI 10.1016/S0065-2687(08)60068-0
[2]   DIAGENESIS OF FE AND S IN AMAZON INNER SHELF MUDS - APPARENT DOMINANCE OF FE REDUCTION AND IMPLICATIONS FOR THE GENESIS OF IRONSTONES [J].
ALLER, RC ;
MACKIN, JE ;
COX, RT .
CONTINENTAL SHELF RESEARCH, 1986, 6 (1-2) :263-289
[3]   COMPLETE OXIDATION OF SOLID-PHASE SULFIDES BY MANGANESE AND BACTERIA IN ANOXIC MARINE-SEDIMENTS [J].
ALLER, RC ;
RUDE, PD .
GEOCHIMICA ET COSMOCHIMICA ACTA, 1988, 52 (03) :751-765
[4]   TH-234-U-238 DISEQUILIBRIUM IN NEAR-SHORE SEDIMENT - PARTICLE REWORKING AND DIAGENETIC TIME SCALES [J].
ALLER, RC ;
COCHRAN, JK .
EARTH AND PLANETARY SCIENCE LETTERS, 1976, 29 (01) :37-50
[5]  
ALLER RC, 1980, ADV GEOPHYS, V22, P237
[6]   CONCENTRATION, OXIDATION-STATE, AND PARTICULATE FLUX OF URANIUM IN THE BLACK-SEA [J].
ANDERSON, RF ;
FLEISHER, MQ ;
LEHURAY, AP .
GEOCHIMICA ET COSMOCHIMICA ACTA, 1989, 53 (09) :2215-2224
[7]   URANIUM DEPOSITION IN SAANICH INLET SEDIMENTS, VANCOUVER ISLAND [J].
ANDERSON, RF ;
LEHURAY, AP ;
FLEISHER, MQ ;
MURRAY, JW .
GEOCHIMICA ET COSMOCHIMICA ACTA, 1989, 53 (09) :2205-2213
[8]  
ANDERSON RF, 1987, URANIUM, V3, P145
[9]   URANIUM REMOVAL IN OCEANIC SEDIMENTS AND THE OCEANIC-U BALANCE [J].
BARNES, CE ;
COCHRAN, JK .
EARTH AND PLANETARY SCIENCE LETTERS, 1990, 97 (1-2) :94-101
[10]   GEOCHEMISTRY OF URANIUM IN BLACK-SEA SEDIMENTS [J].
BARNES, CE ;
COCHRAN, JK .
DEEP-SEA RESEARCH PART A-OCEANOGRAPHIC RESEARCH PAPERS, 1991, 38 :S1237-S1254