2009 Portland GSA Annual Meeting (18-21 October 2009)

Paper No. 4
Presentation Time: 9:00 AM-6:00 PM


DHAR, Sujoy Kumar, Brooklyn Technical High School, 29 Fort Greene Pl, Brooklyn, NY 11271, NGUYEN, Y-Lan Le, High School for Health Professions and Human Services, 345 E 15th St, Ny, NY 10003 and DHAR, Ratan, Earth and Physical Sciences, York College of the City University of New York, 94-20, Guy R. Brewer Blvd, Jamaica, NY 11451, nysjdhar@yahoo.com

Preliminary elemental data were produced for systematic withdrawal of five auger samples from Jamaica Bay, NY, distributed on parallel line of 250 m, and 3 m perpendicular to the high tidal water edge and 76 cm depth. The 15 cm sections were analyzed for a suite of 26 elements including major and trace elements by using XRF. Toxic metals As, Se, Mo, Ag, Cd, Sn, Sb, Hg were not detected in any section of these cores. Average Fe concentration was found to be 6.5 ± 2.9 g/kg and distributed consistently in increased concentration with depth which also agree with the observed sediment colors on site; more darker towards surface. Patchy spatial and vertical variation of major and trace elements Cl, K, Ca and Ti, Cr, Mn, Zr, Ba may be caused by sediment weathering and local environmental influences possibly waste water discharge, a major potential source of contaminants. Cu (0.05 ± 0.01 g/kg) and Sn (0.11 ± 0.14 g/kg) were detected at entire vertical profile in one location (JB-A-C-1) next to park and/fishing activities, suggests the secondary enrichment of these metals due to anthropogenic activities. Highest Pb (0.03 ± 0.03 g/kg) up to 132 mg/kg and Zn (0.03 ± 0.02 g/kg) up to 75 mg/kg were also found in this core. Limited variation (<10%) of Sr and Rb observed in all cores indicates that they are attributed from the primary sedimentation. Trace but detectable Co(<0.15 g/kg) and Ni (<0.05 mg/kg) were found sporadically in few sections of all cores.