| 摘要 |
<p>Downhole seismic sources that may be compatible measurement-while-drilling systems. The downhole seismic sources are integrated into drill string components, including drill collars of the bottom hole assembly. The downhole seismic sources may generate a low swept frequency signal suitable for imaging around the drill-string and ahead of the drill bit. Integrated downhole seismic systems including a downhole seismic source, receivers and optionally data processing capabilities. The integrated systems may be configured to determine the distance and orientation of bed boundaries, including ahead of the drill bit up to about 200 m to 500 m in depth. Methods for downhole seismic, including single well and cross-well seismic. The methods may include obtaining seismic information ahead of the drill bit.</p> |
