The article deals with the peculiarities of killing wells in carbonate reservoirs of the East Siberian fields (Danilovsky cluster), complicated by abnormally high formation pressures. The process of killing is complicated by low temperatures of the environment and low reservoir temperatures of the object under operation. Taking into account the experience of previous works and risks of gas and water leakages it is recommended to consider application of blocking compounds in addition to high density killing fluids for the Verkhneosinskoye horizon (formation B1). The results of laboratory tests of heavy killing fluids with the density of up to 1.8 g/cm3 on the basis of combined solutions of bromine salts (fluid No.1) and chlorides with calcium nitrate (fluid No.2) are represented. If there is a necessity to use heavy technological fluids, including those for well preservation, the attention was paid to the corrosion rate during prolonged exposure of a heavy killing fluid to the well equipment. Based on the results of laboratory tests the combined calcium and zinc bromide solution was recommended for field tests. Field tests of killing technology with heavy fluid were carried out and no complications and negative effect on productivity were revealed - the fluid is recommended for killing in B1 formation conditions. There was also tested a suspension blocking compound on the basis of the said heavy fluid with the addition of calcium carbonate. When absorptions occurred the application of the blocking composition under consideration didn't allow absorptions control, the blocking composition was not recommended for application. Instant filtration composition was successfully used to restore circulation, applied in conditions of intensive absorptions, this technology is recommended for more detailed researches for conditions of the object under consideration.
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