变速成图方法及应用研究

研究了地震速度和变速成图传统方法中影响成图精度的主要因素 ,指出了传统方法中造成误差较大、准确性较低的原因。从解决传统方法中存在的问题入手 ,提出了相应的速度场建立和变速成图方法 :通过提高叠加速度分辨率 ,利用模型层析法或模型反演法实现叠加速度到层速度的转换 ,建立空间速度场 ,速度校正和时深转换。实际资料应用表明 ,该方法提高了速度场建立和变速成图精度 ,解决了山前高陡构造以及低幅度构造地区的变速成图问题。

Research on Variable-Velocity Structure Mapping and its Application

The paper analyzses the primary factors that have influence on the mapping precision of traditional methods for building seismic velocity fields and structure mapping by variable-velocity, points out the causes of big errors and poor accuracy related to the use of conventional methods. Starting from solving the problems existing in the traditional methods, the paper presents a new method for building seismic velocity fields and structure mapping by variable-velocity. The conversion from stacking velocity to interval velocity is realized by using modeling tomographic or modeling inversion through enhancing the resolution of stacking velocity. The construction of the spatial velocity field, velocity correction and time-depth conversion are also achieved. The furnished examples and practical application of the method in many areas show that the method can improve the precision of velocity field and structure mapping, resolve structure mapping problems by variable-velocity on steep dip structure and low-relief structure in front of a mountain.