A dual-source flyback through-casing acoustic logging method and device

Abstract

The invention discloses a dual-source flyback over-casing acoustic logging method and device. The logging device includes an acoustic casing and a dual emission source arranged in the acoustic casing, a receiving array, a metal cylinder and a metal cylinder placed in the acoustic casing. The transmission and reception control circuit in the barrel, the transmission and reception control circuit is connected to the dual transmission sources and can implement dual-source flyback excitation for the dual transmission sources, the transmission and reception control circuit is connected to the receiving array and performs signal processing on the signals on the receiving array Conditioning, synchronous acquisition and data processing and can upload the data to the ground instrument. The present invention is based on dual-source flyback technology, which can effectively suppress casing waves and improve the signal-to-noise ratio of formation waves from the source of data collection. The acoustic logging device based on this technology can measure formation sound velocity in casing wells, The formation sound velocity can also be obtained under bad conditions, which improves the application range of the cased hole formation evaluation acoustic logging.

Description

technical field [0001] The present invention relates to a geophysical well logging method and device, in particular to a method and device for measuring the sound velocity of formation longitudinal waves under casing wave interference in a cased well based on dual-source flyback technology. Background technique [0002] Acoustic logging is an important geophysical logging method. One of its main purposes is to measure the formation compressional wave velocity, and then evaluate the formation porosity and other reservoir parameters. This has become a must-test item in open-hole wells . At present, cased hole acoustic logging mainly includes acoustic amplitude logging, variable density logging, and sector cement bonding logging, etc., all of which are used to evaluate the quality of cement bonding, not for the purpose of measuring formation acoustic parameters. In recent years, as people strengthen the development of remaining oil and gas in old oilfields, or some wells canno...

AI Technical Summary

Problems solved by technology

It is difficult to accurately extract the sound velocity of the formation from the acoustic wave data collected in this way.

Images