ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

2pUW26. Sediment layer structure and composition effects on pulse propagation at the Atlantic generating station (AGS) site.

Kevin P. Bongiovanni

Rensselaer Polytechnic Inst., Troy, NY 12180-3590

Moshen Badiey

Univ. of Delaware, Newark, DE 19716

William L. Siegmann

Rensselaer Polytechnic Inst., Troy, NY 12180-3590

An investigation of broadband pulse propagation in a shallow water environment is performed using high-order frequency- and time-domain parabolic equation models. High resolution geoacoustical profiles are constructed from cores obtained at the extensively sampled AGS site which lies 5 miles offshore southern New Jersey. These, along with CTD and detailed bathymetric data, are used to model the environment. Acoustic experiments recently conducted at this site [M. Badiey et al., 3593--3604 (1994)] provide broadband acoustic data for comparisons with the modeling predictions. Simulations of transmission loss versus frequency show very good agreement with experimental data over several different propagation tracks. Time-domain simulations are compared with time series of pressure variations generated by the impulsive experimental source along corresponding tracks. Strongly range-dependent mechanisms are observed over short ranges with both models and can be correlated with specific sediment features. A discussion of the modeling results in connection with both environmental and acoustic data sets will be given.