Lithologic interpretation method by means of least square method

Abstract

The invention relates to a lithologic interpretation method by means of least square method. The method includes the steps of: 1) analyzing and acquiring content of elements in a stratigraphic rock by performing X-ray fluorescent analysis to drill cuttings in a researched region; 2) according to logging data, performing average value calculation to different element values of lithology of different stratigraphic units to obtain a lithology-element comparison data bank of all wells in the stratum; 3) acquiring a main element characteristic content curve standard map which reflects different lithology of different stratigraphic units in the same region; 4) comparing element content curve maps of measured data with the standard map and comparing the similarity through the least square method, wherein the lithology, being corresponding to the map with the highest similarity, is the lithology of the measured data. The method can achieve quantitative interpretation and recognition of the stratum lithology, increases coincidence rate of interpretation of the stratum lithology, and reduces misjudgment on the stratum lithology due to insufficient experience of on-site workers.

Description

technical field [0001] The present invention relates to the field of geology and mud logging engineering services, in particular to a lithology interpretation and evaluation method based on the "least square product" method, which can be used for quantitative interpretation and identification of lithology in well logging formations at the well site, and can be used for magmatic rocks and sedimentary rocks Quantitative interpretation and identification, intuitive and rapid identification of formation lithology. Background technique [0002] In the process of oil and gas drilling, identification of formation lithology is the most basic and most important technology. Timely and accurate identification of formation lithology is an important guarantee for correct selection of construction parameters, ensuring drilling safety, and improving oil and gas exploration efficiency. The traditional lithology identification method currently used is mainly to qualitatively describe the for...

AI Technical Summary

Problems solved by technology

This method is often due to the differences in the experience of the field personnel, the rock naming or feature description of the same cuttings sample will be quite different, and even cause misjudgment of the formation lithology

[0003] With the rapid development of new oil drilling technology, such as the application of PDC drill bit and gas drilling technology and the increasing difficulty of oil and gas exploration and development, the cuttings returned from the bottom of the well are very fine, even in the form of dust. Conventional cuttings logging technology Difficult to identify stratum lithology

The promotion and application of X-ray fluorescence element logging technology has added a new method to lithology identification, but the application research of this technology is not deep enough at present, and the lithology interpretation method is lacking

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