Rock resistivity has a close relationship with lithology, reservoir properties and oil-bearing capacity. Resistivity measurement while drilling (MWD) device is designed to judge Lithology, divide oil/gas/water layer and analyze the oil-bearing capacity, permeability and porosity of reservoir according to measurements of rock resistivity. It is used for real-time evaluation of stratum. The porous stratum is commonly high in resistivity. Low resistivity measured often implies the existence of saturation water. However, the collected information that reflects the resistivity signal contains a lot of noise components. It is difficult to accurately reflect the formation resistivity. The near-bit RMWD device based on wavelet packet noise reduction algorithm can measure the resistivity of stratum at first time because of the method of measurement while drilling. It can also precisely denoise the measured data of lateral resistivity, bit resistivity and azimuthal resistivity by the algorithm of wavelet packet decomposition and the best wavelet tree of reconstruction signal based on information entropy, so as to improve the accuracy and reliability of resistivity measurement.

You can access this article if you purchase or spend a download.