Acoustic reverberation in littoral ocean waveguides is often controlled by small-scale seabed heterogeneities. Thus, validation of reverberation models and development of realistic simulations require measurements of those scales. Clutter features for mid-frequency active sonars span scales from order 1–1000 m. The smaller scale seabed features O(1–10)m, however, are not generally represented in bathymetric data, even from modern hull-mounted multibeam systems. One promising tool for isolation and quantitative measurement of small-scale seabed features is an AUV with a source (800–3500 Hz) and towed array. Recent measurements from the Clutter09 experiment in the Straits of Sicily show that O(1–10)m scale seabed features (e.g., carbonate chimneys on mud volcanoes) are resolved and can be quantified. [Work supported by the Office of Naval Research OA321 and the NATO Undersea Research Centre.]