1. GENERALINTRODUCTION
Cross dipole array induction utilizes monopole, dipoleand cross dipole techniques to acquire such formationparameters as porosity, permeability, transverse waveanisotropy and direction, fracture density and orientation,crustal stress, etc.
Mounted with the dipole transmitting transducer of controllablefrequency and the ultra-low frequency Stoneley wavetransmitting transducer, the tool has unique advantagesin terms of acquiring the transverse wave velocity of softformation and evaluating formation velocity anisotropy.
2. SYSTEM FEATURES
| Max pressure | 140MPa (20,305psi) |
| Max temperature | 175°C (347°F ), 2h |
| Downhole tool power | AC180 ± 10V, 50 ± 2Hz |
| OD | Φ99mm (3.9in) |
| Transducer specifications | |
| Transmitter | Near and far monopole transducers, and cross dipole transducer |
| Receiver | 4x8 transducer matrix |
| S - wave measurement range | 230 - 2300 μs/m |
| P - wave measurement range | 130 - 800 μs/m |
| Stonely filter measurement range | 400 - 3000 μs/m |
| Vertical resolution | 152.4cm (6.0in) |
| Recommended logging speed | 550m/h (1804ft/h) |
3. SYSTEM FEATURES
- With functions of monopole, dipole and cross dipole fullwave logging;
- The basic frequency of dipole source is optional (Min.1.2kHz), reducing dispersion to the lowest;
- Monopole high-power transmitter with high SNR;
- Effective sound insulation to eliminate the influence ofdirect wave.
4、APPLICATION
- Highly deviated well, extended reach horizontal well and slimopen hole logging;
- Key wells, complex wells and those where conventional arrayacoustic tool cannot apply;
- Exploratory wells, gas wells, shale gas wells or those withspecial imaging logging requirements.
