论文部分内容阅读
储层中的天然裂缝对油气产能有重要影响,但由于井下数据有限,仅依靠井下数据一般难以确定裂缝系统分布网络的非均质性,同时也难以获取裂缝数值模拟大量的静态参数,因此对裂缝的定量评价面临着较大挑战。选取库车前陆冲断带露头区典型构造样式,描述不同构造样式下(即逆冲推覆单斜、高角度逆冲挤压背斜、基底遮挡滑脱型背斜)独特的裂缝发育分布特征,探讨不同构造样式下的裂缝发育规律。结果表明:逆冲推覆单斜发育2期裂缝,走向主要为北北西向,以晚期近直立开启缝为主,早期高角度斜交缝被方解石半充填—全充填,裂缝面密度自核部向翼部有降低趋势;高角度逆冲挤压背斜总体发育3期裂缝,以北北西向、北西西向为主,早期裂缝基本被方解石完全充填,中晚期裂缝开启,且切穿单砂体并收敛于层面,具有明显层控性,背斜的陡翼裂缝较缓翼发育强烈,呈现出不对称的分布规律;基底遮挡滑脱型背斜被强挤压一翼发育2期高角度斜交开启缝,裂缝方向呈北北西向和北东东向,被遮挡一翼砂岩遭受变形较弱,基本未见明显裂缝。不同构造样式下的裂缝发育规律对裂缝数值模拟和有利储层分布预测均具有重要意义。
However, due to the limited downhole data, it is generally difficult to determine the heterogeneity of the fracture network distribution network based solely on the downhole data, and it is also difficult to obtain a large number of static parameters for fracture numerical simulation. Therefore, The quantitative evaluation of cracks is facing a big challenge. The typical tectonic style of the outcrop of Kuqa foreland thrust belt is selected to describe the unique distribution of fracture development under different tectonic styles (ie, thrust nappe monoclinic, high angle thrust crush anticline, basement occlusion slipping anticline) , To explore the crack development rules under different tectonic styles. The results show that the second-stage fractures developed by thrusting and monoclinic development are mainly north-northwest direction and late-stage near-standing opening faults. The early high-angle diagonal seams are semi-filled and filled with calcite, and the density of fracture surface is from the core There is a downward trend toward the wing part. The high-angle thrusting anticline generally developed stage 3 fractures, mainly in the north, southwest and north west-west directions. The early fractures were basically filled with calcite, the middle and late fractures were opened, And converges to the level, with obvious stratigraphic control. The anticlinal steep flank cracks developed more slowly and developed asymmetrically. The basement occlusion slippage anticline was developed by a strong extrusion wing. The directions of cracks and cracks are north-northwest and north-east-east, and the sandstone covered by one wing is weakly deformed with no obvious cracks. The fracture development rules under different tectonic styles are of great significance to the numerical simulation of fractures and the prediction of favorable reservoir distribution.