中国石油勘探 ›› 2023, Vol. 28 ›› Issue (5): 117-125.DOI: 10.3969/j.issn.1672-7703.2023.05.010

• 工程技术 • 上一篇    下一篇

近地表砾岩发育区地震速度特征分析及应用——以库车山前带YKB地区为例

韩波1,王保才2,骆福嵩2,张渝悦1,韩博2,夏永涛2,丁维2   

  1. 1中国石化石油物探技术研究院有限公司; 2中国石化西北油田分公司勘探开发研究院
  • 出版日期:2023-09-15 发布日期:2023-09-15
  • 作者简介:韩波(1982-),男,山东新泰人,硕士,2009年毕业于中国石油大学(北京),副研究员,现主要从事油气地球物理勘探综合研究工作。地址:江苏省南京市江宁区上高路219号,邮政编码:211103。
  • 基金资助:
    国家自然科学基金企业创新发展联合基金项目“克拉通盆地内部走滑断裂体系成因及控藏机制研究——以塔里木盆地为例”(U21B2063)。

Analysis and application of seismic velocity characteristics in areas with near surface conglomerate development: a case study of YKB area in Kuqa piedmont zone

Han Bo1,Wang Baocai2,Luo Fusong2,Zhang Yuyue1,Han Bo2,Xia Yongtao2,Ding Wei2   

  1. 1 Sinopec Geophysical Research Institute Co., Ltd.; 2 Research Institute of Exploration and Development, Sinopec Northwest Oilfield Company
  • Online:2023-09-15 Published:2023-09-15

摘要: 在山前带地震勘探中通常应用叠加速度进行变速成图,但对近地表砾岩如何影响下伏地层叠加速度的研究较少,也缺乏有效的叠加速度校正方法。应用楔状模型模拟近地表砾岩特征,对不同位置处地震波走时—入射角曲线特征进行分析,并以库车山前带YKB地区为例,开展地震正演进行验证,证实了近地表高速砾岩会导致砾岩尖灭点之下形成异常高的叠加速度,使速度由扇根到扇端方向出现“低—高—低—高”的横向变化。基于此认识通过速度趋势线法校正叠加速度,并与井速度约束法进行了成图对比,结果揭示:由速度趋势线法得出的构造图地层产状与实测结果更接近、深度误差更小,证明了该方法在低勘探程度的山前带近地表砾岩发育区的有效性。

关键词: 山前带, 叠加速度, 模型正演, 走时—入射角曲线, 变速成图, 低勘探程度

Abstract: In seismic exploration in the piedmont zone, stacking velocity is generally used for variable velocity mapping. However, there is few study on the influence of the near surface conglomerate on the stacking velocity of the underlying strata, and there is a lack of effective methods for stacking velocity correction. The wedge-shaped model is applied to simulate the near surface conglomerates, and the characteristics of seismic wave travel time-incident angle curves at various locations are analyzed. In addition, by taking YKB area in Kuqa piedmont zone as an example, seismic forward modeling is conducted to verify the results, which confirm that an abnormally high stacking velocity is formed below the pinch out points caused by the near surface high-speed conglomerate, resulting in a lateral velocity variation of “low-high-low-high” from the inner-fan to the outer-fan. Based on this understanding, the stacking velocity is corrected by velocity trend line method, and the result map is compared with that by well velocity constraint method. The results show that the formation occurrence in the structural map obtained by the velocity trend line method is closer to the measured results, with a smaller depth error, which proves the effectiveness of this method in the near surface conglomerate development area in the piedmont zone with low level of exploration.

中图分类号: