Ramirez Marc S.,Edwards Carl M.,Forgang Stanislav W.,Kouchmeshky Babak
申请号：
US201615166717
公开号：
US10145976(B2)
申请日:
2016.05.27
申请国别(地区):
美国
年份:
2018
代理人:
Cantor Colburn LLP
摘要：
A nuclear magnetic resonance apparatus for estimating properties of an earth formation includes a carrier configured to be deployed in a borehole in the earth formation and at least one transmitting assembly disposed in the carrier and configured to generate an oscillating magnetic field in a volume of interest within the earth formation. The apparatus also includes at least one receiving assembly disposed in the carrier and configured to detect a nuclear magnetic resonance (NMR) signal originating in the volume of interest. In this apparatus, the receiving assembly includes at least a first longitudinal region with a loop coil and a butterfly coil, the loop coil central axis being located over a region of the magnet assembly where a static magnetic field is predominantly along an azimuthal direction to the carrier and the butterfly coil being at least partially overlapped with the loop coil to reduce mutual coupling.
