Abstract Relation between the dielectric constant of rocks, sampled from the western exploring area of Daqing Oil Field, and water saturation, salinity is developed. Effect of shale and water distribution on the dielectric constant is discussed through experiments on artificial core samples and shale samples. The mixing law that describes the relation between dielectric constant and water saturation is revised and a new one characterized by the area is proposed.
Abstract Daqing Lamadian oil field is the largest oil field with a gascap in China. Monitoring, controlling and adjusting techniques have been used extensively to minimize cross flow. An inverted nine-spot pattern was used in the oil-bearing area. Gas-bearing layers were not perforated and there was a 400 to 600m buffer zone of oil and gas migration left between oil-and gas-bearing areas. A monitoring system for gas-cap performance was established. Flow between the oilbearing and gas-bearing layers has been successfully controlled and a relatively stable oil-gas interface has been maintained for 20 years.
Abstract The production profile can be obtained with a continuous flow meter and a gradiomanometer. Slip and other factors in the vertical string for two phase (oil-water) flow, affect the data and make it very difficult to interpret. To solve this problem, studies were made in a simulation well of the relationship between the rotary speed of the spinner and the water holdup, and the ratio of the apparent velocity to the average fluid velocity and water holdup. Four relationship charts and interpretation programs were developed A total model of the simulating experiment was built, which can interpret multiple zone oil/water production rates to draw their profile map, and quantitatively interpret oil bubbles moving upward, and interpret the reverse rotation of the spinner in the vertical string. The data obtained from 20 wells show that the method has high resolution so that low producing layers can be detected and quantitatively interpreted. Also, intra-formationaJ interpretations for thick formations can be made. In conjunction with the water intake profile of the surrounding injection well, a plot of water-injection versus oil-production can also be drawn.
Abstract In Daqing Oilfield, since 1988 1524 oil wells have been fractured by this technique. This is 21.4 percent of all fractured oil wells. The average oil production improvement of each well is 15.0 t/d, a 1.5 fold increase over conventionally fractured wells. The cumulative oil production improvement is 340.3 × 104 tons 203 water wells were fractured by TMFUD, 33 0 percent of all the fractured water injection wells The mean water injection improvement per day is 80.8 m3/d, and the cumulative water injection rate is increased by 146.6 × 104m3. The multifracture fracturing technique can be used to stimulate low permeability thin interlayers and as many as 6 to 9 independent sub-layers without moving the string.
Abstract This technique including explosive reforming and explosive welding is mainly adopted for repairing downhole damaged casing in an oilfield. It is based on the principle of explosive action to restore a deformed casing and to weld the damaged section.
