The texture of surficial sediments in north-central Long Island Sound off Hammonasset Beach State Park, Connecticut

Abstract

Grain-size analyses were performed on 53 samples from a 13.4 km2 area of northeastern Long Island Sound. The relative grain-size frequency distributions and related statistics are reported herein. Descriptions of the benthic character from video tapes and still camera photographs of the bottom at these stations, and 8 others, are also presented. The southeastern part of the study area is characterized by coarse, moderately sorted sands. Gravelly sediments are confined to high-energy near-shore locations. Poorly sorted fine sands, silty sands, and sandy silts dominate the remainder of the study area. These textural distributions reflect the underlying geology, but are primarily a product of Holocene oceanographic conditions. INTRODUCTION The purpose of this study was to accurately measure the grain size distributions of the surficial sediment samples from this part of north-central Long Island Sound, to determine the frequency distributions, and to calculate statistical descriptions that adequately characterize these samples. These grain-size data will eventually be used to help describe the sedimentary processes active in this portion of north-central Long Island Sound, and to evaluate near-shore sand and gravel resources. Other potential uses for these textural data include benthic biologic studies that evaluate faunal distributions and relate them to habitats, and geochemical studies involving the transport and deposition of pollutants.