Analysis of Affecting Factors of Cold Production of Extra Heavy Oil with Horizontal Wells in Block M

Abstract

The Venezuelan block M located in the Orinoco heavy oil belt. It has been developed with clustered horizontal wells via foamy oil cold production, the horizontal well cold development in heavy oil belt has the characteristics of high initial and high cumulative production. Based on the combination of production performance analysis and the establishment of a mechanism model with typical reservoir geological characteristics of the block, the affecting factors of horizontal wells via foamy oil cold production in extra heavy oil reservoirs have been systematic investigated. The study shows cold production of the horizontal wells in the block is affected by thickness of the reservoir, permeability, horizontal section length of oil layer encountered and physical properties of interlayer. With the increase of formation capacity and horizontal section length of oil layer encountered, the cumulative production of horizontal wells increases. Interlayer affects effective thickness and vertical permeability of the oil layers, thus affects the production of horizontal wells. The closer the interlayer directly above the horizontal well and to the reservoir bottom is, the lower the horizontal well productivity is. The larger the interlayer is, the lower the interlayer permeability is and the more the interlayer is, the lower the horizontal well productivity is. The understanding of affecting factors lays the foundation for improving cold production performance of extra heavy oil reservoirs and reservoir engineering optimization for horizontal well development.KeywordsExtra heavy oilFoamy oilCold productionHorizontal wellProduction performance analysisNumerical simulation