【作者】 陈程；

【导师】 邓宏文；

【作者基本信息】 中国地质大学（北京） ， 矿产普查与勘探， 2003， 博士

【摘要】 改善高含水期油田注水开发效果是世界石油界关注的大问题，它关系到原油产量和老油田开采的经济效益。特别在我国，油田储层多为陆相沉积，油层多，层间、层内和平面非均质性严重，而且近90％的油田均采用早期注水开发方式。这决定30-50％的可采储量要在含水80-98％阶段采出，高含水期成了油田开发的重要阶段。直接影响老油田开采经济效益的是能否准确地判断地下油水分布。油田生产表明，地下油水分布复杂性直接与储层非均质性有关。因此，精细和定量表征储层非均质性是搞清地下剩余油分布和油田开发部署的关键。 油田开发生产过程是一个减弱储层非均质性影响的过程。开发层系和注采井网与地下储层非均质性的适应程度是决定注水油田开发效果好坏的主要因素。合理的开发层系和注采系统能使由储层非均质性产生的层间、层内和平面矛盾减弱到最小的影响程度，从而能使注水波及体积系数和采收率达到最优化。储层非均质性是客观存在，人们很难改变它。提高开发层系和注采系统对储层非均质性的适应程度是改善注水开发油田效果的重要途径。因此，在建立精细定量地质模型的基础上，从储层非均质性来探讨如何提高注采系统适应程度，制定相应的注采井网经济技术政策参数，对优化部署老油开发调整工作具有重要理论和生产意义。 面对改善高含水期油田注水开发效果的挑战，本文按照现代储层表征技术的要求，积极探索储层描述、剩余油预测和注采井网调整新理论和新方法。拟定了以储层地质知识和概念模型为基础，以储层随机模拟、油藏数值模拟和剩余油分布预测技术为手段，以剩余油分布及其控制因素为研究对象，以优化注采井网参数和调整、部署挖潜措施为目的的技术路线。以河南油区双河油田（双河油田位于南襄盆地泌阳凹陷南缘，储层属于扇三角洲，主要由砂砾岩构成，物性较好，但非均质性严重。90％以上的石油储量分布在扇三角洲前缘。目前，正处于油田开发后期生产）为例，积极探索油田开发后期提高水驱采收率途径，在实践中获得一些重要的成果。 1、利用密井网资料，建立了双河油田扇三角洲前缘储层精细原型模型，形成了储层随机建模所需的地质知识。例如主要微相砂体的平均宽厚比和长—宽关系、各种微相砂体内渗透率分布结构特征等。 2、掌握储层内部砂体和物性的概念性分布状况或轮廓，建立扇三角洲前缘储层精细概念模型。 3、油田开发后期要求研究部门提供精细、定量的油藏描述成果，本文利用精细随机模拟方法建立了双河油田扇三角洲前缘相模拟模型和物性数值模型。根据设计的扇三角洲前缘随机模拟思路，实现了构造模拟、相模拟和物性参数模拟。运用多种模拟方法来模拟不同的对象，如用截断高斯模拟砂、泥分布和微相带，用示性点过程来模拟河道与水下溢岸、河口坝与重力流等。最后形成了扇三角洲前缘储层微相模拟模型和储层物性参数模型。 4、搞清了控制油水运动规律的地质因素，为利用精细储层描述成果分析储量动用状况和剩余油富集部位架起了桥梁，同时给油田开发后期注采井网和注水采液结构调整提供了依据。如在目前注水工艺条件下，渗透率小于0.06μm²的储层基本上不吸水，渗透率在0.06-0.3μm²的储层吸水很差；不出液界限是k_i/K_max≦0.44；夹层展布对油水运动的影响主要是阻挡注入水纵向窜流，减弱重力驱替效果，降低波及体积系数；微相砂体的几何形态及砂体之间的接触关系是控制注入水优先流动路径的主要因素；河道和河口坝无因次采液指数随着含水上升呈现出先降后升的趋势，而无因次采油指数则随着含水上升而下降，席状砂始终处于低产状态，无因次采液和采油指数均小于0.8。席状砂的无因次吸水指数基本上处于下降状态；河口坝的无因次吸水指数在低含水阶段略有下降，中高含水阶段缓慢上升，高含水阶段则快速上升；河道的无因次吸水指数则持续上升，在中含水阶段上升速度最快，在高含水阶段则上升速度变缓。 5、提出了两种基于油藏地质和油藏工程的剩余油预测方法一油井小层剩余潜力和井间剩余油分布非线性预测方法。综合数值模拟、动态分析和其它剩余油监测和描述方法的成果，揭示了扇三角洲前缘剩余油分布规律。目前，剩余油主要分布在前缘席状砂体中，但要重视河口坝、水下分流河道砂体内的剩余油。未弱淹剩余油潜力主要富集在岩性颗粒相对较细和厚度相对较薄的中低渗透储层中。有 40％左右的剩余油分布在孔径小于 10．03 u m的／JWh道中。 6、注采并网不适应油砂体内部非均质性是剩余油形成的主要原因，也是制约着开发效果改善的因素，因此根据储层非均质性来定量研究井冈参数对部署和调整注采系统，最大限度地挖掘地下剩余潜力具有重要的经济意义和理论意义。根据单个微相砂体的钻遇概率与微相砂体的规模，注采井距在 300In左右或井网密度在 11口地f左右是合理的井距和井网密度。在注水压力一定的条件下，要想动用好低渗透油层中的储量，必须缩短注采井距，以提高驱替压力梯度，对于渗透率在100In左右的的以席状砂分布为主的相带，合理的井距最好为200IYl左右。骨架型微相砂体中合理的油水井数比应更多还原

【Abstract】 How to improve the oil-water displacement efficiency which is involved in the fieldwide rate and economical efficiency , concerns the oil business all over world. Especially in china , nearly 90 percent of oil fields are of continental deposit reservoirs, multiple pay beds, strongly heterogeneous formations Jfurthermore, they have been produced with the development regime of early-stage waterflooding . That will mean recovering 30-50 percent of commercial reserves during high water-cut stage (water cut between 80 percent and 98 percent),so that this stage will become very important in the oil field development history. What directly influences the production economic efficiency of the old field is whether we could predict correctly the distribution of remaining oil . Field waterflooding performance has indicated the distribution of remaining oil is directly related to the reservoir heterogeneity. So, to characterize detailedly and quantitatively the reservoir heterogeneity is a key to make sure the distribution of remaining oil and make decision to lay out an oil field.The field development is a process of reducing the influence of the reservoir heterogeneity. The adaptability of the development reservoir combination and the flooding pattern to the reservoir heterogeneity is a main factor to determine the flooding efficiency. The proper development reservoir combination and flooding pattern make the effects of the reservoir heterogeneity reduce to the lowest level , so the flooding sweep efficiency and the recovery efficiency will be optimized. One of the important ways to improve the flooding efficiency is to boost the adaptability of the development reservoir combination and the flooding pattern to the reservoir heterogeneity, for the reservoir heterogeneity is objective and not altered by people. Therefore, it is significant theoretically and practically to discuss how to boost the adaptability of the injection-production system to the reservoir heterogeneity and lay down the economical, technical and policy parameters of the flooding pattern on the basis of building the detailed and quantitative geological model of reservoir for the optimized arrangement of the old field development adjustments.In the face of great challenges to improve the flooding efficiency during the high water cut stage, this paper has explored actively the new theories and methods of reservoir description, remaining oil prediction and flooding pattern setting, drawn up a technical line that regards the reservoir geological database and the conceptual model as its foundations, regards the reservoir stochastic modeling ,the reservoir numerical simulation and the remaining oil predictable techniques as its means, regards the distribution of remaining oil and its controls as its research objects ,and regards the optimization of the flooding pattern parameters and adjustment and arrangement of the production measures as its goals. Taking an example of shuanghe oil field (lies on the southern verge of Biyang depression in Nanxiang basin, its reservoirs are interpreted to be fan delta deposit, consist mainly of sandstone and conglomerate, are good in petrophysics and strong in heterogeneity. 90 percent of its petroleum reserves are dispersed in the fan delta front. And now ,it is in the development later stage )in the Henan oildom, this paper has explored actively the ways of enhancing the water drive recovery efficiency and obtained some paramountfruits.1.The detailed prototype model of fan delta front reservoir and some geological knowledges that will be required to generate a stochastic model of heterogeneous reservoirs were established and acquired based on the dense pattern. For example, The average ratios of width/thickness and length/width of the main microfacies sandbodies, the structure of permeability of each microfacies sandbody and so on.2.The detailed conceptual model of fan delta front reservoir, was built with analyseing the distribution of sandbodies and petrophysical properties3.The stochastic models o更多还原