Breathing prediction of fracture deviated wellbore through flooding mechanism

Abstract

Wellbore breathing is a common occurrence during drilling operations, but the down hole mechanism and how it manifests itself in surface and subsurface processes, is not well understood. It often result in a drilling fluid gain at surface and are misidentified as a kick, resulting in unneeded shut in periods and associated non-productive time (NPT). Further, misidentification of wellbore breathing as underbalance often results in increases in mud weight, which only exacerbates the problem and may cause lost circulation. This work focuses on characterization of the wellbore breathing phenomenon in practical contexts of the Pressure, volume, temperature and time behavior of the components involved in the surface and subsurface system. Methods for identification, differentiation from kicks and underbalance, mitigation and prevention of wellbore breathing are proposed, in addition to operational procedures for safe continuance of drilling operations. The coupled nature of Pressure, volume, temperature as they connect to wellbore breathing, are analyzed in detail in order to quantify their effects and how they can inhibit identification of wellbore breathing. There are many complications associated with abnormally high fluid pressures in over pressured formations. Pore pressure will directly influence all components of operations as well as drilling, earth science studies, completion, and production. Correct predictions of pore pressure and fracture pressure area unit very important aspects to the assembly and completion of safe, time economical, and price economical comes. Information of pressure distribution within the formation will greatly cut back complexities related to drilling and finishing a well. This research also proposes adaptation of the hydraulic fracturing pump-in flow back test for the interpretation of wellbore breathing events and estimation of the minimum horizontal stress. This work presents estimates of the minimum horizontal stress for fractured zones in five wells using PWD data recorded during wellbore breathing events. These estimates were verified qualitatively, when possible, by comparing across multiple connections and with available LOT data.