Synthetic seismograms are used for structural and/or stratigraphic interpretation of seismic sections. There are many commercially-available software packages for generating synthetic seismograms from sonic and/or density logs. Most of these packages are based upon the assumptions that: (1) the formations have zero dip, and (2) the well is vertical or near-vertical. In most cases, the first assumption is not true, and many times the second premise is unrealistic. This study discusses a method to generate a synthetic seismogram for a directionally-drilled well. The seismogram was constructed from the sonic, density, and directional survey logs, with the well corrected to vertical and with the dips of the synthetic traces matched to the formation dips. Tbis is an easy and quick method which offers an improvement over "conventional" synthetic seismograms. 合成震波常用來與震測剖面做比導,以之來研究地質構造及地層學。有許多商業化的套裝軟體使用聲波井測來產生合成電波。這些套裝軟體大部分基於如下的假設:1.地層無傾斜。2.垂直或近乎垂直之鑽井。但大部分的情況下,第一個假設時是不真實的,且第二個假設在許多時候也不實際。位了改善上述的問題,本研究利用聲波井測,密度井測,井程定向井測及地層傾斜井測,乃發展一種能產生定向井合成震波的方法,俱有井偏修正及地層傾斜修正的合成震波使其與地層剖面產生最佳匹配。可應用於石油工程之定向鑽井,產生與震測剖面有良好匹配之合成震波。