Logging facies identification for horizontal wells in meandering river deposition under wide well spacing——taking L oilfield as an example

As the meandering river swings frequently, it has drastic lateral variation of reservoirs. Offshore oilfields mainly utilize the pattern of horizontal wells with wide well spacing for single sand body development. Limited by the influence of the horizontal well trajectory and the noise effect, there exists multi solutions in logging facies identification for horizontal wells. Therefore, it is necessary to establish identification standards suitable for offshore oilfields. By taking L oilfield with good seismic quality in Bohai sea as an example, by means of coherence slices and RMS attribute fusion technology, the attribute information of sand and mud was formed, and the sedimentary microfacies was determined by calibrating the drilling data. Based on the normalization of logging data, through plane profile and well log-seismic data combination, the logging facies of horizontal wells were determined by using conventional logging series and AziTrak edge sounding data. Based on this technology mentioned above, a geological-logging sedimentary model has been formed by establishing the quantitative identification standards of abandoned channels of meandering river sediments, late paleochannels, lateral interlayers and point dams suitable for offshore oilfields, which provides a basis for fine management of oil and gas reservoirs.