叠前深度偏移技术在煤田岩浆岩侵入区构造成像中的应用

中煤科工集团西安研究院有限公司,陕西 西安 710077

煤田勘探; 地震资料处理; Kirchhoff叠前深度偏移; 岩浆岩侵入

Application of prestack depth migration technique in the structure imaging of coalfield magmatite intrusion area
ZHANG Xian-xu

(CCTEG Xi'an Research Institute,Xi'an 710077,China)

coal exploration; seismic data processing; kirchhoff pre-stack depth migration; magmatic intrusion

DOI: 10.13800/j.cnki.xakjdxxb.2015.0213

备注

煤田深部地层由于岩浆岩侵入导致煤层下覆地层结构复杂,同时勘探区内地表存在村庄等障碍物,施工中无法使用规则观测系统进行数据采集,叠后和叠前时间偏移都无法确保成像的精度和正确性,导致煤田地质和地震解释工作者对井田整体构造以及岩浆侵入区构造认识不清,进而无法有效保障煤田正常的安全生产。为了有效解决这一问题,文中在处理解释一体化的思想指导下,结合地质、测井和钻井等资料,按照叠后时间域、叠前时间域以及叠前深度域的速度迭代求取和建模步骤,精确求取地层速度,使用Kirchhoff叠前深度偏移方法,完成构造成像研究。最终结果使得深部构造和岩浆岩侵入区地层接触关系更加清晰,对于揭示煤田整体构造,特别是深部岩浆岩侵入区翼部陡倾地层的构造成像有了较大的提升。为煤田地质工作者对井田岩浆岩侵入区构造的正确认识打下坚实的基础。本研究认为,在煤田复杂构造地区开展叠前深度偏移研究,对改善和提高岩浆岩侵入区的构造成像是一条有效途径。

In exploration areas,the structure of coalfield deep became complicated because of the magmatic intrusion to the coal deep strata.At the same time,the regular observation system cannot be used because of the obstacles in surface such as villages.Therefore post-stack time migration and pre-stack imaging inability to ensure the imaging of accuracy and correctness.So geologists and interpreters unable to explain the whole structure and clearly understand the structures of magmatic intrusions area,further the coal mine production safety cannot be guaranteed.In order to solve this problem,we together with the interpreter combined with geological,logging and drilling data,according to the steps of building post-stack time domain,pre-stack time domain and pre-stack depth domain velocity calculation and modeling methods.We obtain the satisfied section by Kirchhoff pre-stack depth migration method.The results has a larger upgraded in the imaging quality for the whole structure of coalfield and magmatic intrusion area.It helps geologists to have a clear understanding of the structure.Our research thought that to carry out pre-stack depth migration technique in coalfield complex structure area is an effective way to improving the imaging quality of magmatic intrusion structure.