L油田为一大型的埋深、薄层、特稠油构造地层油藏 ,在其东区C块对 2种井距进行了蒸汽吞吐转驱试验。结果表明 ,埋深 90 0m以下 ,厚度 10m左右的砂砾岩储层 ,在 7MPa左右较高压力下转驱仍然是可行的。采用先进的注采及监测配套工艺 ,使注汽井井底干度始终保持在 70 %以上 ,采注比 1 4以上 ,预测最终采收率比一直保持吞吐方式提高 2 8%以上 L Oilfield is a large deep, thin and heavy heavy oil structural stratigraphic reservoirs. Steam flooding tests were conducted on two wellbores in Block C in the eastern part. The results show that the sandstone reservoir below 90 m depth and 10 m thickness is still feasible at higher pressure of about 7 MPa. Adopting advanced injection and production monitoring technologies, the dry-well of the steam injection well is always maintained at above 70% and the recovery ratio is more than 14, the predicted ultimate recovery ratio is more than 28% more than that of the throughput method