The invention discloses a near-bit electromagnetic wave electrical resistivity and gamma
logging instrument. The near-bit electromagnetic wave electrical resistivity and gamma
logging instrument comprises a transmitting section and a receiving section. The transmitting section comprises a gamma
detector, a gravity sensor, a transmitting circuit unit, an electromagnetic wave transmitting device, and a transmitting antenna; and the receiving section comprises receiving antennas, a receiving circuit unit,
logging-while-frilling electrical resistivity (EPR), and logging-while-frilling electromagnetic wave electrical resistivity (AER). An electromagnetic wave
signal is subjected to power amplification and is transmitted and output by the transmitting antenna, the electromagnetic wave
signal, output by the transmitting antenna and passing through underground well floors, is received by the two receiving antennas, andthe
signal is subjected to
differential amplification and pass filter, and is sent to a
digital signal processing unit for
processing after being converted into a
digital signal; a gamma signal adopts
wireless electromagnetic transmission and a
drill collar is used as a medium to transmit an
electric signal to complete
short distance wireless transmission of information; near-bit gamma measurement can be provided, the distance to a
drill bit is short, accurate measurementis achieved, and a reservoir boundary can be measured earlier.