摘要
新站油田天然裂缝发育,部分裂缝开启,注入水进入隔层泥岩和高含泥油层,泥岩吸水后膨胀和蠕变,对套管施加巨大、不均衡的载荷,造成套变。为了有效控制套损井的产生,特别在东西向小断层附近,由于断层走向与最大主应力方向平行,断层及断裂带内伴生裂缝均在最大主应力的作用下,趋于开启状态,更易造成成片套损。建议通过加密调整、周期注水和降低注水量等方法,控制注采比和注水压力,从而达到抑制套损井的产生的目的。通过研究得出,在距断层100m以内不布注水井,开展加密试验,以有效降低注水压力,并对注水压力高的套损修复井,严格控制注水量,防止造成二次套损。
Natural fracture is rich and some fractures are in opening state in Xinzhan oilfield.When injected water enters into the mudstone layer and high mud-bearing oil layer,the mudstone begins to expand and creep after water absorption,which can exert huge and uneven pressure and lead to casing deformation.Especially near the small faults in east-west direction ,the associated fractures in faults and faulted belts tend to be in opening state because the fault trend is parallel to the direction of maximum principal stress,causing the casing damage.In order to control effectively the appearance of casing damage that the injection to production ratio and injection pressure should be controlled by water injection and decreasing injection rate.Study shows that the water injection well,the author suggests infilling adjustment, cycle wells should not be arranged within 100m fault distance and the infilling test should be done to effectively pressure.The water injection rate of casing damage repaired well should be controlled casing damage decrease the injection to avoid the secondary
出处
《中外能源》
CAS
2008年第1期60-63,共4页
Sino-Global Energy
关键词
断层
裂缝
注水压力
泥岩
主应力方向
套变
注采比
fault
fracture
water injection pressure
mudstone
principal stress direction
casing deformation
injection to production ratio
