多信息多技术深度速度建模技术在复杂构造中的应用研究

The technical research of the velocity modeling using multi-tech and multi-information in complex area

中国西部等复杂区的油气勘探潜力较大,但地质条件复杂,造成常规偏移成像的精度不够,给解释带来了诸多困难。根据其地质特点,围绕高精度成像的需求,开展高精度速度建模技术研究,形成了配套的技术策略,为其进一步改善复杂区的成像精度,落实勘探目标奠定了基础。在该配套技术中:基于真地表的速度建模技术可以通过真地表数据准备来解决现有大圆滑偏移基准面对成像波场的改变、初至层析近地表建模技术的应用弥补了反射建模技术在近地表应用的不足、多信息约束速度建模可提高速度模型的可靠性、各向异性假设的成像技术更加接近复杂构造地下介质的假设,这些技术的配套应用可以有效提高复杂区成像位置的精度和准确度。在实际资料中的应用充分说明该技术的有效性。

There are abundant oil and gas exploration potential in the complex zone of the western China. Due to the complex geological conditions,the accuracy of prestack time migration imaging is not enough and brought many difficulties to interpretation. According to the geological characteristics of the area and the demand of high precision imaging,we carried out study to form a complete set of high precision velocity modeling technology strategy. The method can further improve the imaging accuracy to meet the exploration targets. The velocity modeling techniques based on "real" surface can be really ready to solve the unfavorable effect of the large smooth migration datum which can destroy the actual wave field. And the applications of first arrival tomography near surface modeling technology can make up the lack of reflection modeling technology in the near surface. The joint velocity modeling of the more technology,more information and anisotropic imaging can effectively improve the rationality of image position in the complex area. The set of technology has achieved good result in the actual data.