摘要 |
<p>Methods and apparatus for determining the speed of a signal species, such as an acoustic signal, in a multilayered medium is described. The multilayer medium, generally, has a first and second layer (e.g. oil and water), whereby first and second signals are transmitted across particular distances in the medium such that a second distance differs from a first distance, and whereby the time of flight of each signal can be used in order to determine the speed of the signals species in one or both of the first and second layer. In other words, in some cases, the speed of sound can be determined in oil and/or water, or the like.</p> |