Determination of Eight Kinds of Elements in Cuttings by Logging Special Laser-induced Breakdown Spectrometer / 分析化学

ABSTRACT

It is one of the necessary work in oil and gas exploration and development to record the logging of different depth cuttings.In this study, a laser induced breakdown spectrometer ( LIBS-Trace) developed by our research group was used for the lithology logging in the field of oil and gas exploration and development.A total of 60 samples from a drilling site in the Southwest China were divided into training set and test set, and then element quantitative analysis model of eight elements of Si, Al, Ca, K, Mg, Mn, Ti and Fe was established based on support vector machine regression ( SVR).The results showed that the mean percentage prediction errors (MPE) predicted by this method were Si 5.68%, Al 7.22%, Ca 7.45%, K 9.76%, Mg 8.79%, Mn 11.9%, Ti 11.4% and Fe 10.4%, which met the requirements of logging work.In addition, according to the logging process and demand, the instrument hardware and software were modified, and the quantitative model integrated in the instrument was optimiZed.The results showed that the algorithm model combined with the instrument could quickly complete the quantitative analysis of rock debris samples, and exhibited potential application value and broad application prospect in oil and gas exploration and development.