| 摘要 |
<p>Device for detection of changes of resistivity or dielectrical properties due to changes of fluid compositions in the near-well area 0-500 m about a well (1) in a geological formation (9), comprising an electrically conductive tubing string (4), e.g. a liner pipe or an other fixedly arranged tube or openhole completion in the well (1). The characteristic by the invention is: a) an electrical energy source (24); b) a signal generator (22) for generation of electromagnetic signals (25) to; c) at least one transmitter antenna (2) for electromagnetic waves (26), arranged preferably above an oil/water contact, on a fixed first position on the tubing string (4), and arranged for essentially to guide the electromagnetic waves along the tubing string (4); d) one or more receiver antennas (81, 82, .., 8n) for guided electromagnetic waves along the tubing string (4), arranged on other fixed positions along the tubing string (4); e) devices (80) for receiving of signals (851, 852, .. 85n) induced in the receiver antennas (81, 82, .., 8n) due to wave impedance gradients along the tubing string (4) in rocks or fluids in the geological formation (9) and in the electrically conductive tubing string (4); f) signal processing means (82) for processing of the received signals (851, 852, .., 85n); g) communication devices (100, 200) for transmission of signals (105) representing the electrical signals (851, 852, .., 85n), and for receiving control signals (205).</p> |
