TY - JOUR
T1 - Spatial and vertical distributions of elements in sediments of the Colorado River delta and Upper Gulf of California
AU - Shumilin, Evgueni N.
AU - Carriquiry, José D.
AU - Camacho-Ibar, Víctor F.
AU - Sapozhnikov, Dmitry
AU - Kalmykov, Stepan
AU - Sánchez, Alberto
AU - Aguíiga-García, Sergio
AU - Sapozhnikov, Yuri A.
N1 - Funding Information:
We greatly appreciate the helpful suggestions of the anonymous reviewers on this paper. This research was supported through funding from Mexican National Polytechnical Institute (No. 966614) and by a grant from Mexican Consejo Nacional de Ciencia y Technologı́a (CONACYT) No. 27728-T to E.N. Shumilin, by grants from the University of Baja California No. 4088 and No. 4041 to J.D. Carriquiry, and by a grant from CONACYT No. 3929-T to V.F. Camacho-Ibar and J.D. Carriquiry. Thanks to Dr. Ellis Glazier and M.S. Martin Gonzalez Sushinsky for editing the English-language text.
PY - 2002/10
Y1 - 2002/10
N2 - The abundance of major components (Fe, Ca, K, and organic carbon) and trace elements was analyzed in surface sediments and core samples from the Colorado River delta (CRD) and the Upper Gulf of California (UGC) using instrumental neutron activation analysis. The spatial distribution patterns of the elements studied are consistent with the model of sedimentary dynamics proposed for this area [Mar. Geol. 158 (1999) 125]: intense tidal resuspension of sediments in the delta with subsequent transport of suspended particulate matter in a southerly direction, followed by sedimentation of fine-grained material in a depocenter near the southwestern margin of the UGC. Concentrations of most of the elements are higher in the surface sediments of this depocenter. The gradual mixing of terrigenous and marine biogenic materials, normally expected for the estuarine sediments, was not detected in the CRD-UGC system because of homogenization of the sediments by tides and wind. Vertical profiles of element contents in samples of the sediment core collected in the depocenter area revealed (i) almost no anthropogenic contamination of the area by environmentally important trace elements such as Cr, Co, Sb, and As; (ii) a twofold decrease of Fe, Sc, Cr, and Co in upper core sediments; and (iii) the enrichment of the sediments at 60-62 cm depth in the core, in calcium carbonate, Ca, Sr, and the Eun/Smn shale-normalized ratio along with a depletion in this layer of Fe, Sc, Cr, Co, light rare-earth elements (REEs), and some other elements of terrigenous origin, presumably caused by the dilution of fluvial terrigenous material by biogenic carbonates, which were probably introduced at this level in the sediments by the action of a strong episodic winter storm, followed by the advective transport of shell fragments from the coastal clam banks or as a result of strong planktonic bloom.
AB - The abundance of major components (Fe, Ca, K, and organic carbon) and trace elements was analyzed in surface sediments and core samples from the Colorado River delta (CRD) and the Upper Gulf of California (UGC) using instrumental neutron activation analysis. The spatial distribution patterns of the elements studied are consistent with the model of sedimentary dynamics proposed for this area [Mar. Geol. 158 (1999) 125]: intense tidal resuspension of sediments in the delta with subsequent transport of suspended particulate matter in a southerly direction, followed by sedimentation of fine-grained material in a depocenter near the southwestern margin of the UGC. Concentrations of most of the elements are higher in the surface sediments of this depocenter. The gradual mixing of terrigenous and marine biogenic materials, normally expected for the estuarine sediments, was not detected in the CRD-UGC system because of homogenization of the sediments by tides and wind. Vertical profiles of element contents in samples of the sediment core collected in the depocenter area revealed (i) almost no anthropogenic contamination of the area by environmentally important trace elements such as Cr, Co, Sb, and As; (ii) a twofold decrease of Fe, Sc, Cr, and Co in upper core sediments; and (iii) the enrichment of the sediments at 60-62 cm depth in the core, in calcium carbonate, Ca, Sr, and the Eun/Smn shale-normalized ratio along with a depletion in this layer of Fe, Sc, Cr, Co, light rare-earth elements (REEs), and some other elements of terrigenous origin, presumably caused by the dilution of fluvial terrigenous material by biogenic carbonates, which were probably introduced at this level in the sediments by the action of a strong episodic winter storm, followed by the advective transport of shell fragments from the coastal clam banks or as a result of strong planktonic bloom.
KW - Colorado River delta
KW - Major elements
KW - Sediments
KW - Trace elements
KW - Upper Gulf of California
UR - http://www.scopus.com/inward/record.url?scp=0036802222&partnerID=8YFLogxK
U2 - 10.1016/S0304-4203(02)00059-2
DO - 10.1016/S0304-4203(02)00059-2
M3 - Artículo
SN - 0304-4203
VL - 79
SP - 113
EP - 131
JO - Marine Chemistry
JF - Marine Chemistry
IS - 3-4
ER -