长庆安塞油田剩余油开发区DAS井地联采技术探索与实践

Research and Practice of DAS Joint VSP and 3D Surface Seismic Technology Used in Remaining Oil Development Zone of Ansai Oilfield,Changqing

中国石油集团东方地球物理勘探有限责任公司结合长庆安塞油田开发区“三低”和“双复杂”的典型特点,面对老油田剩余油预测突出问题,从井地、井震协同一体化研究思路出发,开展国内首次面向开发区剩余油预测的多井DAS三维井地联采技术探索与实践,通过井地联合勘探实现地面地震测量和井中地震测量的优势互补,取得了良好成果。(1)通过井震同步井驱处理,三维地震资料保真度和分辨率明显提升,有效频带拓宽8%以上。(2)通过井地、井震一体化油藏静态描述剩余油预测研究,减少了单一地面地震解释成果多解性,可分辨更小地质单元,为油田精细开发提供了可靠的资料依据。(3)DAS三维井地联采配套技术支撑了安塞油田新增地质储量,并通过低产低效井组挖潜措施调整,提产效果明显。通过本次研究得出,井地联合立体探测是提升油田开发过程中微幅构造刻画和储层、流体预测精度的有效技术手段,形成的技术可推动物探技术向油田开发延伸、向井地立体探测发展,可为老油田稳产增效、推进高效开发提供支撑。

The development zone of Ansai Oilfield,Changqing,was typically characterized for its low-permeability,low-porosity and low-yield conditions and complicated surface and underground conditions.To solve the problem related to prediction of remaining oil from the old field,BGP Inc.adopted the research mindset of borehole-surface seismic integration and developed and tested the DAS joint VSP and 3D surface seismic technology to predict the remaining oil of the development zone for the first time in China.The DAS joint VSP and 3D surface seismic exploration led to reciprocation of the advantages between surface seismic survey and in-the-well seismic survey,thus achieving good results.(1)Based on synchronous well drive processing,the fidelity and resolution of 3D seismic data were apparently improved,widening the effective frequency bands by more than 8 percent.(2)Based on the study of remaining oil prediction by means of well-seismic and borehole-surface seismic integrated description of static reservoir,the possibilities of the surface single seismic interpretations was reduced and the smaller geological units was able to be identified,providing the reliable data for fine development of the oilfield.(3)The DAS joint VSP and 3D surface seismic technology helped Ansai Oilfield increase its geological reserve and effectively raised the production by adjusting the measures for tapping the potential of the low-yield and low-efficiency well patterns.The study indicates that the DAS joint VSP and 3D surface seismic technology is an effective technological method to improve characterization of micro structure and the accuracy of reservoir and fluid prediction in the oilfield development process.This technology can help geophysical technology extend into oilfield development and develop towards borehole-surface seismic stereoscopic exploration,providing support for old oilfields to increase production and efficiency and accelerate high-efficiency development.