HAPKE, C.J.; LENTZ, E.E.; GAYES, P.T.; MCCOY, C.A.; HEHRE, R.; SCHWAB, W.C., and WILLIAMS, S.J., 2010. A review of sediment budget imbalances along Fire Island, New York: can nearshore geologic framework and patterns of shoreline change explain the deficit? Journal of Coastal Research, 26(3), 510-522. West Palm Beach (Florida), ISSN 0749-0208.Sediment budget analyses conducted for annual to decadal timescales report variable magnitudes of littoral transport along the south shore of Long Island, New York. It is well documented that the primary transport component is directed alongshore from east to west, but relatively little information has been reported concerning the directions or magnitudes of cross-shore components. Our review of budget calculations for the Fire Island coastal compartment (between Moriches and Fire Island Inlets) indicates an average deficit of 217,700 m 3 /y. Updrift shoreline erosion, redistribution of nourishment fills, and reworking of inner-shelf deposits have been proposed as the potential sources of additional sediment needed to rectify budget residuals. Each of these sources is probably relevant over various spatial and temporal scales, but previous studies of sediment texture and provenance, inner-shelf geologic mapping, and beach profile comparison indicate that reworking of inner-shelf deposits is the source most likely to resolve budget discrepancies over the broadest scales. This suggests that an onshore component of sediment transport is likely more important along Fire Island than previously thought. Our discussion focuses on relations between geomorphology, inner-shelf geologic framework, and historic shoreline change along Fire Island and the potential pathways by which reworked, inner-shelf sediments are likely transported toward the shoreline.ADDITIONAL INDEX WORDS: Long Island, Fire Island, sediment budget, cross-shore transport, shoreline change, nearshore bathymetry, geologic framework.

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[1] Natural geochemical tracers ( 222 Rn, 3 H, 3 He, and 4 He) were used to assess submarine groundwater discharge (SGD) along the continental shelf west of the Mississippi River. In order to assess SGD, groundwater, surface water, and sediment samples were collected on land and during six 4-day cruises aboard the R/V Pelican between March 2003 and May 2004. A box model approach was used to quantify sources and sinks of 222 Rn in the study area and to calculate SGD rates. SGD estimates were we based on two end member values for the potential advecting fluids: (1) that supported by 226 Ra in the sediments; and (2) groundwater activities measured in monitoring wells. Calculated 222 Rn SGD rates based on sediment supported activities ranged from 0.04 to 0.14 cm d À1 , and estimates based on monitoring well activities ranged from 0.01 to 0.07 cm d À1 and corresponds to 1.41 km 3 yr À1 of discharged water over our study area, equivalent to <1% of the Mississippi River during the same time frame. 3He and 4 He, longer-lived tracers, exhibited significantly greater anomalies in the eastern portion of the study area which corresponds with greater oil and gas extraction and the release of formation water into the water column in this region. While the total SGD was relatively minor, potential sources of SGD are many and we suggest formation water associated with oil and gas extraction, geothermal convection, and seawater recirculation are the primary sources with a minimal contribution from terrestrially derived topography driven flow.