首页>
外国专利>
Nuclear magnetic resonance logging with azimuthal resolution using gradient coils
Nuclear magnetic resonance logging with azimuthal resolution using gradient coils
展开▼
机译:使用梯度线圈以方位角分辨率进行核磁共振测井
展开▼
页面导航
摘要
著录项
相似文献
摘要
The present invention relates generally to an apparatus and method for obtaining an azimuthally resolved nuclear magnetic resonance measurement of an earth formation traversed by a borehole. The measurement can be made while drilling or using a wireline tool (20). At least one gradient coil (56) is positioned circumferentially around the tool (20). A magnetic field is produced by the coil in a region of the formation facing the coil. The magnetic field is substantially parallel to the static magnetic field produced by a pair of permanent magnets (44,46) which form a part of the tool (20). The additional field causes an additional phase shift for spins located in the region so that the spins subjected to the additional field do not form a spin-echo.
展开▼