Abstract

The actual physical and mechanical properties of the reservoir and its stress-strain state (SSS) may differ from the predicted values of the stability model at the pre-drilling stage.

Clay, fractured, weakly cemented or brittle rocks that are exposed to SSS or chemical effects of drilling mud change their elastic-strength properties and are prone to collapse, which leads to a whole range of undesirable consequences.

Rock caving is a valuable source of information about the SSS of the near-well space during drilling. This article discusses the conditions for the appearance and characteristics of rock cavings. Various types of rock cavings obtained during drilling at the perimeter fields of the Gazpromneft group companies are analyzed, and correlations with 1D geomechanical models of well stability are shown.

Key words:

cavings, wellbore instability, geomechanical support, geomechanical modeling, drilling efficiency, monitoring of drilled rock, stress-strain state, geological and technological research

References

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Authors

S.I. Gabitov, Lead-specialist, Gazpromneft-Science&Technology Center LLC
75-79 D, Moika River Embankment, Saint Petersburg, 190000, Russia
E-mail: Gabitov.SI@gazpromneft-ntc.ru

A.S. Gotsulyak, Сhief-specialist, Gazpromneft-Science&Technology Center LLC
Saint-Petersburg, Russian Federation
E-mail: Gotsulyak.AS@gazpromneft-ntc.ru

I.S. Chebyshev, Сhief-specialist, Gazpromneft-Science&Technology Center LLC
Saint-Petersburg, Russian Federation
E-mail: Chebyshev.IS@gazpromneft-ntc.ru

T.Z. Akhmetshin, PhD student, Ufa State Petroleum Technological University
1, Kosmonavtov st., Ufa, 450064, Russian Federation
E-mail: atr93@mail.ru

For citation:

S.I. Gabitov, A.S. Gotsulyak, I.S. Chebyshev, T.R. Akhmetshin Analiz obval'noj porody v processe burenija kak instrument dlja bezopasnogo stroitel'stva skvazhiny [Rock cavings analysis during drilling as tool for safe well construction]. Neftyanaya Provintsiya, No. 1(25), 2021. pp. 124-140. DOI https://doi.org/10.25689/NP.2021.1.124-140 (in Russian)