喇嘛店油气田气顶流动单元及其对开发的影响

因气顶、油气界面的存在及严重的陆相储层非均质性，使气顶油气田与纯气田、纯油田的开发明显不同。针对井网较难控制的砂体窄小、微相、岩性、物性快变区，用离散井点的储层参数进行各种纯数学方法的平面内差成图方法，将很难客观、细致地揭示流动单元。为此提出使用大量成因信息与沉积模式进行平面微相精细研究以控制复杂的微相级单砂体，用微相内能量相单元精细研究以揭示单砂体内部变化规律，再结合渗流系数、存储系数、净毛比划分流动单元的能量相控流动单元的研究方法；并以喇嘛店气顶油气田为例，用此在SⅠ油层组的2小层识别出4种24处微相、5类47个流动单元，因差异显著、平面分布复杂的不同类型流动单元的气层油淹速度与程度不同，将造成严重的平面指进型油淹、低渗型残气区、气油界面呈多指形复杂曲面，且气油界面的快升，将造成严重的损能、损油、损气。

A STUDY OF FLOW UNITS OF GAS CAP IN LAMADIAN OIL/GAS FIELD AND THEIR INFLUENCES ON GAS DEVELOPMENT

Development of oil/gas field with gas cap is quite different with pure gas field or pure oilfield due to the existence of gas cap and oil-gas contact and strong heterogeneity of nonmarine reservoirs. In areas where sandbodies are small and narrow and microfacies, lithology and physical properties change rapidly, it is hard to objectively and precisely reveal flow units through plane interpolation mapping of reservoir parameters in discrete well points by using various pure mathematical methods. To solve this problem, an energy phase-controlled fluid unit division method is presented in this paper. It uses a large amount of genetic information and depositional models to study in detail the plane distribution of microfacies for control of single sandbody at microfacies level, reveals the internal change patterns of single sandbody through detailed study of the energy phase units in microfacies, and divides fluid units in combination with percolation coefficient, storage coefficient and net-to-gross ratio. Lamadian oil/gas field with gas cap is selected for case study. Twenty-four microfacies zones of 4 types and 47 flow units of 5 types are identified in 2 sublayers of SI layer group. Different types of flow units with complex plane distribution have different oiling-out velocities and degrees, so they might cause serious oiled-out of plane fingering type, residual gas zone of low permeability type and gas-oil contact with complex multiple fingering curved surface, and rapid ascending of gas-oil contact might cause serious loss of energy, oil, and gas.