The Xujiaweizi fault depression is one of depressions with rather abundant deep natural gas resources in the northern part of Songhuajiang-Liaohe Basin. Based on seismic prospecting and drilling data, using single well calibration seismic inversion method, es⁃tablished relationship between staged depression evolution and corresponding sediment filling response and discussed continental rift lake basin coal development characteristics. The study has shown that the evolution of Xujiaweizi fault depression has experienced three stages namely initial period, peak period and decline period, Every period has distinct tectonic landform and provenance features, thus formed great differenced sedimentary systems, these differences also reflected on coal development in fault depressions. Most coals developed during decline period with high abundance and large extent, mainly in lake basin shallow silting up area;peak period the second, coals limited to gentle slope side;while during initial period mainly coarse clastic quick filling, with least developed coals. Combined with seismic inversion and single well statistics, multiple high value coal thickness zones are around deep wells Song No. 3, Xu No.27 and Xu No.13 areas, the result has significance in deep natural gas distribution determination.%徐家围子断陷是松辽盆地北部深层天然气资源较为丰富的断陷之一。依据地震、钻井等资料，选用单井标定地震反演的方法，建立了断陷演化的阶段性和相应沉积充填的响应关系，探讨了陆相断陷湖盆煤的发育特征。研究认为徐家围子断陷演化经历了三个时期，即断陷初始期、断陷鼎盛期和断陷衰退期，每个时期具有不同的构造地貌特点和物源特点，形成了差异悬殊的沉积体系，这种差异性也体现在断陷内煤的发育特征上。煤在断陷衰退期沉积中最为发育，丰度高且面积广，主要分布于湖盆於浅处；断陷鼎盛期次之，煤局限于缓坡一侧；而断陷初始期主要为粗碎屑快速充填，煤层最不发育。结合地震反演及单井统计，煤层厚度在宋深3井区、徐深27井区、徐深13井区等形成多个高值区，该结果对进一步明确深层天然气资源分布具有重要意义。
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