Известия Томского политехнического университета: Инжиниринг георесурсов (Jun 2018)
Reasons of water volume increasing in wells after hydraulic gap in homogeneous plates
Abstract
Relevance. The issues of decreasing the share of water in the volume of output are currently extremely urgent and can be solved everywhere. Production of hydrocarbons that lie in a complex and heterogeneous reservoir, using high-performance technologies can lead to complications, including those associated with increased water cut and impossibility of its subsequent reduction. The reason for this problem is often insufficient understanding of geological structure of the deposit. The main aim of the study is to justify the causes of high water cut values of well production after hydraulic fracturing on the example of the Vatyeganskoye oil field, taking into account the effect of formation anisotropy on watercut values in conditions of different locations of producing and injection wells. Methods: geological and field analysis of the development of operational facility; analysis, comparison and interpretation of the results of geophysical methods of well research; methods of lithologic-facies analysis; methods of statistical processing of geological-field and geological-geophysical data. Results. The authors have determined the characteristic of a reservoir section at which high values of water proportion in the «starting» well flow rates are observed after hydraulic fracturing of formation. Three main types of the JV 1 section of the Vatiegan oil field are identified. In the case of hydrodynamically connected reservoir, the priority is the intensification of the inflow from the roofing part (reper-foration), with involvement of water-saturated intervals in the «two-layer» type of the reservoir structure, the repair and insulation works are determinant. The least probability of watering the production of wells after fracturing was noted in the wells with an aged sandy body located in the roof of the section and clogged with a plantar part with a small fraction of the water-saturated strata.
