Lithology while drilling and reservoir characteristics recognizing method

Abstract

A lithology while drilling and reservoir characteristics recognizing method comprises the following steps: (1), establishing data analysis software and hardware equipment; (2), mounting vibration signal measuring equipment; (3), transmitting vibration acoustic wave signals by a vibration transducer to an analog filter; (4), filtering useless frequency bands in the signals and transmitting useful frequency bands to a high fidelity amplifier by the analog filter; (5), amplifying, strengthening, and transmitting the signals to a digital filter by the high fidelity amplifier; (6), transmitting power spectral density of the signals to a wavelet transformation unit by a power spectrum analysis unit, (7), performing wavelet decomposition, reconstruction and noise elimination on the signals by the wavelet transformation unit; and (8), unfolding restored true signals in spectrographs and energy spectrum charts by a Fourier transformation unit, and determining multiple kinds of lithology and reservoir fluid characteristics by recognizing each group of spectrum lines. The method detects and filters the vibration acoustic wave signals, extracts stratum information, and obtains the lithology and the reservoir fluid characteristics through noise elimination and spectral analysis.

Description

technical field [0001] The invention relates to drilling-while-drilling mud logging and measurement technology in the oil drilling process, in particular to drilling tool stress wave detection and analysis technology. Background technique [0002] In conventional geological mud logging, geological stratification, horizon identification and cuttings description are mainly carried out based on drilling time, cuttings samples and gas measurement values. However, for the lithology of thin layers and interlayers that appear in the formation, we often cannot accurately describe them in the case of non-intensified sampling intervals or coring, and the loss of blocks in sand samples and the experience of geologists will result in the description of cuttings The distortion of the cuttings reduces the coincidence rate of the section described by the cuttings. With the extensive use of PDC bits, the drilling speed has been greatly increased. However, because the working principle of P...

AI Technical Summary

Problems solved by technology

When using a PDC bit, because it has no cone and small teeth, the vibration characteristics reflected to the ground are weaker than that of the cone bit, which increases the difficulty of analysis and judgment

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