The pebbles in this photograph taken at Herring Cove Beach are evidence of underlying glacial till in the Provincelands. Water turbulence can suspend sand grains, but can only drag larger material-pebbles and rocks-up and down the beach face. While most of the sand in the Provincetown area has been transported along the shoreline by littoral forces, the stony material shown here was probably deposited by glacial ice or by streams of the outwash plains.    Peter@PeterRomanelli.com    508-487-4570