A method is described by which the reflection properties of the seabed can be estimated from the fall-off with time of intensity received on a single hydrophone, tens of water depths away from a broadband source in shallow water. The method is simple and directly applicable to most active sonars. The theoretical basis of the method is described and results presented using experimental data measured in a shallow water region of the Mediterranean Sea. Seabed properties are deduced directly by the method in the form of the rate of change of reflection loss with respect to an angle close to grazing. An extension to the method is proposed whereby seabed sound speed, density and attenuation can be estimated. Good agreement is shown between the results of the method and the results of matched field inversions carried out in the same area using a large-aperture vertical line array. A similar method using target echoes, instead of direct arrivals, is also demonstrated. The features of the method that make it attractive as a candidate for through the sensor probing of the environment are discussed.