Small-bore gamma-ray spectra well logging device as well as data acquisition transmission and self-stabilization method

Abstract

The invention discloses a small-bore gamma-ray spectra well logging device as well as a data acquisition transmission and self-stabilization method. In order to achieve the aim of continuous gamma-ray spectra well logging, the small-bore gamma-ray spectra well logging device is provided. The small-bore gamma-ray spectra well logging device comprises a BGO scintillation crystal probe, a Ba self-stabilization source, a photomultiplier, a first amplifier, a pole zero cancellation circuit, a second amplifier, a base line restoring circuit, a high voltage module, a self-stabilization circuit, a sampling hold circuit, a threshold comparing circuit, an A / D conversion circuit, an address latch, a first microprocessor, a double-port RAM, a second microprocessor and a time-base circuit, so that the data throughput rate is improved; a synchronization mechanism is designed between the two microprocessors to guarantee the completeness of a gamma-ray spectra data frame. The data frame is like an FIFO, and the gamma-ray spectra data frame which is written at first by the microprocessor 1 is taken away from the microprocessor 2 at first; the microprocessor 1 bears high-speed gamma pulse acquisition, functions of data reading, combination processing, automatic spectra stabilization and the like are realized by the microprocessor 2, and the spectra data are sent to a ground system through an asynchronous serial port in real time.

Description

technical field [0001] The invention relates to the field of well logging, in particular to a small-diameter gamma energy spectrum logging device for measuring radioactive mineral content with high precision. Background technique [0002] Natural gamma ray spectrum logging is a logging method for measuring and analyzing rock natural gamma radiation in the borehole, and measuring the contents of uranium, thorium and potassium in the formation to study the formation properties of the well profile. At present, the application of domestic gamma-ray spectrum logging tools in the petroleum industry is mainly to identify lithology, study sedimentary environment, oil-generating layers, and find reservoirs through the U, Th, and K contents measured by natural gamma-ray spectrum logging. , Determination of clay content and other purposes, characterized by a small content measurement range and a large diameter of the logging tool (generally greater than 90mm). In uranium ore explorati...

AI Technical Summary

Problems solved by technology

In uranium ore exploration, due to the high content of radioactive substances and strong gamma rays in the borehole, these logging tools are not suitable for the measurement requirements of uranium ore exploration.

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