【摘要】 在山区或地表复杂地区进行地震勘探,采用基于地表一致性假设的静校正将会严重影响勘探效果,该影响主要源于地表一致性假设存在着不合理因素,如较高的低速带、巨厚的低速带、基岩裸露、地形起伏较大等。为分析一致性假设静校正偏差产生的原因及大小,构建一地形起伏、基岩出露的复杂模型,通过正演其射线路径,对比其时距曲线与理论时距曲线的差异,以及二者静校正量误差大小。模型分析证实该差异与偏移距、地震波穿透深度及基准面高程之间存在直接的联系,据此提出了改进方法,如浮动基准面校正及分块静校正等。理论模型和实际地震资料试算表明,使用改进的方法可有效改善地震时间剖面同相轴聚焦效果及连续性。更多还原

【Abstract】 To carry out seismic prospecting in mountainous or complicated surface area,using statics based on surface consistency hypothesis will bring on serious impact to prospecting effects.The impact is mainly from unreasonable factors existed,such as higher and thicker low-velocity layer,exposed bedrock,and undulating landform etc.For analyzing statics deviation causation and extent based on surface consistency hypothesis,constructed a complicated model with undulating landform and exposed bedrock,through forward modeling of its raypath,contrasted differences between practical time-distance curves and theoretical time-distance curves,as well as statics error magnitude.The model analysis confirmed that direct relation between the differences and offset,penetration depth of seismic wave,datum plane elevation,on these grounds put forward improving methods such as floating datum plane correction and partitioning statics etc.Tentative calculation demonstrated that the modified method can effectively improve seismic section phase axis focusing effect and continuity.更多还原