W2断块低-特低渗油藏细分层调整研究

W2断块属于低-特低渗、多油层、复杂断块油藏，开发过程中，储量水驱动用程度逐渐降低，层间干扰和储量纵向动用不均衡现象日益突出。通过对打开油层层数、厚度、渗透率极差、原油性质对储量动用状况的影响研究，提出了细分层调整合理的油层层数、厚度、渗透率极差和原油性质界限，以及细分层系需要的含油面积、储量规模界限。通过对细分层系调整后W2断块合理压力保持水平、合理采油速度、合理注采井距的研究，提出了W2断块细分层调整后合理的开发政策界限。按照细分层调整方案和开发政策界限研究成果，在W2断块成功地实施了细分层系调整，采收率增加了5.8%，可采储量增加了33.64×10⁴t。

RESEARCH ON FINE DIVISION OF STRATA IN LOW & ULTRALOW PERMEABILITY FAULTBLOCK RESEVOIRS OF W2

Many problems occur such as reducing water flooding degree,interlayer inference and unbalanced vertical sweep in low and ultralow permeability faultblock reservoirs of W2.Based on the research on the limits of the number of perforated Strata,perforated thickness,permeability ratio,oilbearing area and reserve scale,the limits of oilbearing area and reserve scale for fine division of strata is proposed which suits for W2 faultblock reservoirs.The research on reasonable pressure,production rate and producer injector spacing is carried out and the effective limits for production are proposed.Thus,remarkable results,5.8% for recovery efficiency and 33.64×10⁴t for recoverable reserves,have been achieved since fine division of strata in W2 faultblock reservoirs.