基于合成声波测井信息的变速成图技术

目前地震勘探变速成图过程中，地震波层速度参数是通过叠加速度得到的。当地层的速度横向变化剧烈时，地震反射的时距曲线已经严重违反双曲线规律，叠加速度和层速度之间没有固定的函数关系可寻，利用叠加速度转换层速度的误差在所难免。合成声波测井速度是通过声波测井资料和地震资料反演而来，其精度较高，能准确地反应地层声波速度的横向变化规律。从波动力学的角度出发，研究建立声波速度和地震速度的关系，提出了利用合成声波测井速度求取地震波速度的方法，并用于地震勘探变速成图，从而使构造图的精度大幅度提高。

STRUCTURE MAPPING BY VARIABLE VELOCITY BASED ON SYNERGETIC ACOUSTIC LOGGING INFORMATION

Usually，the interval velocity is computed with the stacking velocity in the structure mapping by variable velocity.When the formation velocity changes dramatically in lateral orientation，the wisdom of the use of the stacking process is questioned.In the event that the interval velocity contains rapid lateral changes，the travel-time curve isn′t a hyperbolic curve again.The interval velocity computed with Dix interval velocity formula isn′t precise.The discrepancy increases with the degree of lateral changes.Synergetic acoustic logging velocity is precise，which is inversed by seismic data under control of acoustic logging data.At the same time，it can provide the detail of lateral velocity changes.It is interested that the relationships of different strata in the depth.Generally，roundtrip travel-time has been known.If the Interval velocity is computed，the depth of strata will be known.This paper illustrates the relationship between synergetic acoustic logging velocity and seismic velocity by the theory of wave mechanics，and the exact interval velocity for structure mapping by variable velocity is computed.