The The Yakela Gas Field Gas Reservoir Engineering Studies

The Cretaceous Yakela condensate gas reservoir in Tarim Basin of Xinjiang is characterized by multi-layer, low porosity and medium permeability, with high condensate content, and is a long-axis anticilinal structure with edge waer. Therefore it is of great significance to make research on the development methods of such gas reservoirs in order to develop the gas fields in Tarim Basin.Taking the Yakela condensate gas reservoir as the zone of interest, based on the extensive investigation on development cases of domestic and foreign condensate gas reservoirs and research results, this paper applies the theories, methods and technologies of contemporary geology, reservoir geology, gas reservoir engineering and numerical simulation and has established a complete set of research methods and basic pattern which adapt to development of sandstone gas reservoirs based on integrated research of development geology in such areas as geological models, production test feature, gas well productivity, reservoir infiltration flow, strata classification, energy of edge water, feasibility of cyclic gas injection, development well pattern and spacing, feasibility of development with horizontal wells, and provide a kind of technique and method with good applicability and reference for research and application in similar gas reservoirs. Meanwhile, combining with conventional gas reservoir engineering method and numerical simulation, the writer draws up reasonable limit on production technology, and proposes that the reservoir should be developed mainly by horizontal well plus vertical wells, with the length of horizontal well of 1000m, the reasonable well spacing of 1400m for vertical wells, the perforation ratio for vertical well of 80%, gas production rate of 3%～4%. The gas reservoir is developed using depletion mode, and has obtained the annual gas production of 9.24×10~8m~3 for the gas reservoirAfter implementation, 6 new wells (including 4 vertical wells and 2 horizontal wells) were put into production in 2005. The Daily oil production reached 310t/d, daily gas production of 151×10~4m~3; cumulative oil production of 52.92×10~4t and cumulative gas production of 20.85×10~8m~3。 Economic evaluation shows that Yakela Gas Field offers good economic benefit and strong anti-risk capability.