A Study On Application Of Special Logging Technique In Optimizing Horizontal-well Perforation Depth

Horizontal wells are special deflected wells which enter hydrocarbon reservoir along hydrocarbon reservoir dip attitude and it is generally agreed that the angle of inclination at borehole isn't less than 86 degrees. Horizontal wells could effectively increase disclosure area of hydrocarbon reservoir, improve oil-gas recovery ratio, and is one of the effective means to raise productivity. With oilfield exploitation having entered into late stage and the increasing improvement in level of drilling tech as well as some restrictions on surface condition (e.g. rivers, lakes, villages and towns), only horizontal well development could be applied. To ensure horizontal well development in oilfield, low-watered-out-level & high-abundance-of-oil reservoir should be selected for gun perforation development.Through the applied research on horizontal well guiding of sieve residue log, special technique log and compound logging and combined with regional tectonic analysis, predominant and perfect methods of horizontal-well multiparameter geologic logging guiding have been created.By studying the rules of change in oilfield development of parameters, curves and spectrograms of geochemical log, pyrolysis gas chromatography, batching fluorescence, gasometry and routine logging, especially the magnitude relation analysis of S0+S1 and S2 in geochemical log and the change analysis of nor/isohydrocarbon content and configuration in pyrolysis gas chromatography, evaluation criteria have been created for abundance of oil and watered-out level of horizontal-well hydrocarbon reservoir through many kinds of logging techniques.The widespread use of the achievement of this project in horizontal-well drilling site and horizontal-well logging interpretation & elevation has greatly improved the ability to geologically guide horizontal-well and optimize perforation depth, steadily advanced the accuracy rating in distinguishing remaining oil distribution, and drawn high recognition and attention of exploitation department.