DIVA技术在莺歌海盆地中的应用

Application of DIVA technique in Ying'ge Sea basin.

DIVA技术是一项地震油气检测技术。鉴于莺歌海盆地的地震速度在总体上表现为随深度增加而逐渐增加 ,但在局部有强烈的速度减小现象的特征 ,本文将 DIVA技术用于莺歌海盆地的油气检测。首先依据各层的速度曲线 ,按由浅层至深层的原则 ,编制组合的 DIVA曲线 ;然后将此组合曲线仍按由浅至深的原则编制 DIVA剖面图 ;最后依据 DIVA剖面上显示的速度异常区的可靠程度 ,分级确定有利的含油气区带。该区检测结果表明 ,在浅层 DIVA异常以 类为主 ,在中深层以 类为主。

DIVA (Differential Information Velocity Analysis)technique is a seismic oil/gas detection technique.In view of the character of seismic velocity of Ying'ge Sea basin being generally gradual increase with the depth but locally having the phenomenon of strong velocity decreasing,the paper used the DIVA technique to detect oil and gas in Ying'ge Sea basin.First,drawing out composite DIVA graphs in a principle from shallow to deep based on the velocity graphs in each layer;then drawing out the DIVA sections from these composite graphs based on same principle;finally grading and determining the favorable oil/gas-bearing zones based on reliability of velocity anomaly showed on DIVA sections.The detection results of the region showed the DIVA anomalies mainly are Ⅰ class in shallow layers and mainly are Ⅱ class in medium and deep layers.