杜84块兴Ⅵ组油水界面认识研究

The Research of Oil-water Interface in Xing Ⅵ Formation of Du84 Block

杜84块兴Ⅵ组油层以蒸汽吞吐开发为主,后期将转入直平组合SAGD开发。该油层埋深范围-710^-840m,以厚层块状为主,厚度一般在30~80m,油水关系复杂,为底水油藏,已进入中后期开发阶段。兴Ⅵ组共有直井382口,水平井54口。目前已转入SAGD生产的直井有143口,水平井有21口,累计注汽480.4×104t,累计产油76.1×104t,累计产水403.3×104t,油汽比为0.16,日产液为4118.9t/d,日产油为545.8t/d,含水达到86.7%。兴Ⅵ组油层油水关系复杂,个别直井和水平井长期高含水生产,影响整体开发动用效果。通过测井资料,从电性和物性上深入研究兴Ⅵ组底部油水界面,建立统一的油水识别标准,并借助钻井取心、生产动态资料进一步验证,确定全区油水界面。运用新技术对油水发育进行三维地质建模,为后期兴Ⅵ组整体开发及转入SAGD开发后提供可靠依据。

Steam stimulation is implemented in oil reservoirs in Xing Ⅵ formation of Du84 block currently, and SAGD will be implemented later through the combination of vertical and horizontal wells.Xing VI formation is a reservoir with bottom water and complex oil-water relationship buried from -710 to -840m.The oil reservoirs are thick and massive with the thickness of 30-80re.It has entered into mid-later development stage.There are 382 vertical wells and 54 horizontal wells in Xing VI formation.Among them,143 vertical wells and 21 horizontal wells are produced for SAGD now.Cumulative steam injection,oil production and water production is 480.4×104t,76.1×104t and 403.3×104t respectively.Oil-steam ratio is 0.16.Daily liquid production and oil production is 4118.9t/d and 545.8t/d respectively.Water cut is up to 86.7%.General development effect is influenced for high-water cut production in few vertical and horizontal wells.Based on logging interpretation data,the bottom oil-water interface of Xing VI formation is researched thoroughly on electrical and physical properties.A unified standard of the oil-water identification is established and whole oil-water interface is determined after further verification through core data and production performance data.Three-dimensional geological oil-water development model is established based on the new technology ,which will pro- vide reliable basis for the later integral development and SAGD of Xing Ⅵ formation.