International scientific journal

ISSN: 2663-0419 (electronic version)

ISSN: 2218-8754 (print version)

International scientific journal

ISSN: 2663-0419 (electronic version)

ISSN: 2218-8754 (print version)


Study of geological cross-sections for making design and engineering decisions while drilling under uncertainty

Isayev R.A., Piriverdiyev I.A.

Institute of Oil and Gas of Azerbaijan National Academy of Sciences 9 F. Amirov Str., Baku AZ1000, Azerbaijan:,


To date, a large number of studies have accumulated on gathering and using information about well drilling. The quality of this information has a major influence on the decision-making process while drilling, as in most cases the drilling occurs under uncertainty. Numerous studies and the drilling experience show that the data obtained while drilling require statistical processing and in-depth analysis. The purpose of studies based on probabilistic methods and fuzzy logic is to predict the properties of rocks along the wellbore and to identify homogeneous intervals using a set of features. At the same time, various methods make it possible to assess the properties of rocks using core, cuttings, well logging, and mud logging data while drilling. This article considers the applicability of the proposed methods through examples of specific wells, since their successful application contributes to improving the efficiency of studying geological cross-sections and the quality of information obtained while drilling, as well as improving the quality of decisions. A computational scheme was proposed by the authors for estimating drillability of rocks associated with their properties predicted from integrated mud logging while drilling. Using the results of mud logging while drilling, the ways of building a refined lithological column are shown. The method proposed in the article which plays an important role in making decisions on the choice of process parameters, can be recommended for data analysis during drilling, clarification of lithology and boundaries of certain types of rocks.

Keywords: porosity, hardness, density, mathematical statistics, fuzzy logic, harmonic mean



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DOI: 10.33677/ggianas20210200065