| 摘要 |
A marine electromagnetic streamer includes a plurality of electrodes 19A-P disposed along a longitudinal dimension of the streamer 18B. At least one signal processing module is disposed at a selected position along the streamer. A multipole switch (39, Fig.3) associated with the at least one module is electrically coupled between a signal input of the signal processing module and selected pairs of the electrodes. The switch is configured to enable the selected pairs coupled to the switch such that selection thereof results in at least one of varying electrode spacing and varying electrode offset from an electromagnetic energy source. The processing module may comprise an electrode 28 disposed on its exterior and one multiple switch selection may connect the signal input of the module between the module exterior electrode 28 and a common potential reference line 32 extending the length of the streamer, the line 32 including an electrode in contact with water at an aft longitudinal end of the streamer. |
