A flat security member having a relatively small format, such as a thin board, including at least one through-hole and a method for producing a flat security member. The device has supply element and the apparatus has a supply co-ordination element. + products into products with a boiling point of less than 370\xb0 C. The processing means are able to process the acquired seismic data so as to attenuate seismic events involving reflection of seismic energy at at least one boundary face of the high velocity layer.