鄯善油田地应力、裂缝系统与油田开发

IN-SITU STRESS, FRACTURE SYSTEM AND OIL-FIELD DEVELOPMENT SHANSHAN OILFIELD

以吐哈鄯善油田为例，分析地应力对低渗透砂岩油田裂缝（包括天然裂缝和人工压裂裂缝）的控制作用，研究地应力对低渗透砂岩油田井网部署和注水开发的影响。认为，古构造应力场与天然裂缝的形成、分布及发育程度有关，现今应力场则不仅影响天然裂缝在地下的赋存状态及有效性，而且控制了人工压裂裂缝的形态和延伸方向。低渗透油田的合理开发，应考虑现今地应力状态下的天然裂缝和人工压裂缝的综合影响，开发时，注水压力应低于地层破裂压力，不应沿天然裂缝方向和最大水平主应力方向部署注采井。

Taking Shanshan Oilfields in Turpan-Hami Basin as an example, the control of earth stress over fractures wasanalyzed, and the effect of earth stress on well-net arrangement and waterflooding was studied in low-permeability sondstone oilfield. It is considered that paleo-tectonic stress field was related to the origin, distribution and development of natural fractures; present stress field affects not only the occurrence and validity of natural fractures, but also controlsthe configuration and extensional direction of artificial fractures. For the reasonable development of low-permeabilitySandstone oilfield, the effect of both natural and artificial fractures of present stress field should be considered. In waterflooling, injection pressure should be lower than the formaion forture pressure. The production and injection wellsshould not he arranged along the directions of natural fractures and the maximum horizontal principal stress.