老井封堵技术在川东地区储气库建设中的应用

老井封堵作业是地下储气库建设的重要工作之一。四川盆地川东地区经过多年的开采,目前已进入生产中后期,天然气产量不能满足市场调峰需要,需要存储外来天然气以满足调峰要求。因此,近年来川东地区优选了部分枯竭油气藏作为调峰气藏。由于枯竭油气藏老井井筒的不完整性和复杂的地质构造,天然气在地层中窜漏,破坏了枯竭油气藏的封闭性,需要对老井进行治理。为此,针对川东气田纵向上层位多、生产层位压力系数低、老井固井质量差、套管腐蚀损伤严重等特点以及老井开采情况,提出了老井封堵的技术方案:①固化水堵漏;②注水泥浆封堵产层;③固井质量、套管腐蚀状况检测(套管段铣);④注水泥塞+桥塞封堵。老井封堵重点是产层和井筒,主要采用暂堵技术、套管段铣技术,然后实施产层和井筒封堵。实际应用效果表明:依据封堵方案对老井实施永久性封堵作业后,井口压力为零,达到了有效治理老井的目的,从而确保了调峰气藏的安全平稳运行。

An automatical infill shot method for uniform imaging of target layer

Seismic imaging quality is critical to describing reservoirs. There are many methods that can improve imaging quality; some rely on advanced processing means, whereas others rely on changing the field acquisition methods. However, most of the acquisition methods focus on improving imaging by using infill shots without considering the target-layer illumination energy. Moreover, total infill shooting greatly increases the acquisition cost. In this paper, we present a new method for maximizing the contribution to the target shadow area illumination by automatic local infill shooting. Thus, we designed 2D and 3D models and obtained the depth migration section by forward modeling, infill shots, depth migration, etc. The model results also show that by choosing the most appropriate number of shot points, we can enhance the shadow area energy and improve the target-layer imaging quality at low cost.

基于三维地震解释技术的古潜山钻探目标优选

随着我国油气田勘探开发的不断深入,所面对的勘探开发对象越来越复杂,需要寻找的圈闭越来越小、越来越隐蔽,对地震资料的成像精度、分辨能力要求也越来越高。潜山储集层作为油气聚集和埋藏的重要场所之一,往往具有丰富的地质储量,但其地质构造情况复杂、裂缝发育,具有很强的非均质性,从而导致潜山油气勘探难度较高。以华北某油田潜山及潜山内幕为研究对象,在三维地震资料基础之上,通过开展精细三维地震解释、地震属性分析和地震波吸收系数分析等工作,深入研究了该区潜山及内幕的构造、裂缝发育情况、吸收系数等。研究认为,古潜山裂缝发育、储集性能良好,钻探有利区域应为中高构造部位,并通过进一步研究论证,分别就潜山面及潜山内幕提出了两口滚动开发井井位。