摘要
气井出水导致单井产气量急剧下降,降低气藏的采收率。及时有效识别气井出水点,封堵出水层位,对控水增气及提高气藏采收率至关重要。东海地区为凝析气藏,单井产气量高,产水量低(10m^3/d左右),常规生产测井资料无明显出水特征,不能识别出水层位。当储层压力低于露点压力时,凝析气藏存在反凝析现象,进一步加大气藏出水识别的难度。生产测井技术是识别气井出水的有效手段之一,针对东海地区油气藏开发中存在的难题,通过对东海地区多口井生产测井资料深入分析,总结出一套适合东海地区的低产水凝析气藏出水层位识别方法。基于东海油气藏特征及地层水类型,提出了通过自然伽马对比法、温度测井法、产出剖面测井与饱和度测井技术结合的方法综合识别出水层位。研究结果表明,当气藏水型为氯化钙等高矿化度地层水时,可以通过对比生产测井自然伽马与裸眼井自然伽马曲线准确识别出水层位;在边底水自然水驱的气藏中,温度曲线可以较好地识别出水层位;饱和度测井可通过监测气藏含气饱和度变化识别出水层位。这3种方法都有一定的适用条件,出水层位识别需结合气藏实际开发情况,选择符合区域规律的方法。
Water production by gas reservoirs will lead to a sharp drop in gas production per well and reduce the recovery of gas reservoirs.Identifying reservoir water-outlet point and plugging the water level timely and effectively are very crucial for controlling water,increasing gas production and improving the recovery of gas reservoirs.The reservoirs in East China Sea area are condensate gas reservoirs with high gas production and low water production per well(around 10m 3/d).Conventional production logging data show that the reservoirs there have no obvious outflow characteristics,and the water level cannot be identified.When the pressure is lower than the dew point,retrograde condensate exists in the condensate gas reservoirs,which further aggravates the difficulty in identifying water production by gas reservoirs.Production logging technology is one of the effective methods to identify water production of gas wells.In view of the difficulties in the development of oil and gas reservoirs in the East China Sea area,based on the deep analysis of the production logging data of several wells there,a set of methods suitable for the identification of water production by low-water-production condensate gas reservoirs in the East China Sea were summarized.Based on the characteristics of oil and gas reservoirs and the types of formation water in the East China Sea,a method combining natural gamma comparison,temperature logging,profile logging with saturation logging was proposed to comprehensively identify the water level.The results show that when the water type of gas reservoirs is formation water with high salinity such as calcium chloride,the water level can be accurately identified by comparing the production logging natural gamma curve with the open hole natural gamma curve;the temperature curve can be used to identify the water level in edge-and-bottom water gas reservoirs with natural water flooding;the saturation logging can identify the water level by monitoring the change of gas saturation in gas reservoirs.These
作者
侯振永
付焱鑫
马焕英
武林芳
张志强
Hou Zhenyong;Fu Yanxin;Ma Huanying;Wu Linfang;Zhang Zhiqiang(Oilfield Technology Division,COSL,Sanhe 065201,Hebei;Shanghai Branch,CNOOC,Shanghai 200335)
出处
《长江大学学报（自然科学版）》
CAS
2020年第4期29-33,I0003,I0004,共7页
Journal of Yangtze University(Natural Science Edition)
基金
“十三五”中国海洋石油集团有限公司基金项目“基于油藏开发的可控中子源测井技术国产化应用”(YJB18YF011)。
关键词
生产测井
凝析气
气井出水
低产水
自然伽马对比
温度测井
饱和度测井
出水层位识别
production logging
condensate gas
water production of gas wells
low water production
natural gamma comparison
temperature logging
saturation logging
identification of water level
