The thick and heterogeneous salt section in the Santos Basin, offshore Brazil, imposes great challenges in accessing the pre-salt hydrocarbon reservoirs, especially in relation to seismic imaging, signal quality and depth positioning. Some problems arise from the current velocity models for the salt section, which, for the majority, assume that the salt is a homogeneous halite layer. In the Santos Basin, the commonly assumed salt – halite – only makes up to 80% of the mineral in this section. The inclusion of other salts as stratification in the velocity models, based on seismic attributes, has achieved good results in the last decade, especially for depth resolution. In this work, we analyse the benefits of different velocity models, considering presence/absence of salt stratification and comparing the gross rock volume above the oil–water contact. The results show a significant effect on the depth resolution of the events, as well as on volume estimation, indicating that the greater the reliability captured by the complex velocity models, the greater the confidence in the resulting volumetric information.

巴西近海桑托斯盆地的厚层和非均质盐层对进入盐下油气藏提出了巨大挑战，尤其是在地震成像、信号质量和深度定位方面。盐部分的当前速度模型产生了一些问题，大多数情况下，假设盐是均质岩盐层。在桑托斯盆地，通常认为的盐类——岩盐——仅占该部分矿物的 80%。在过去十年中，基于地震属性将其他盐类作为分层纳入速度模型已取得了良好的结果，尤其是在深度分辨率方面。在这项工作中，我们分析了不同速度模型的好处，考虑是否存在盐层并比较油水界面上方的总岩石体积。结果显示对事件的深度分辨率以及体积估计有显着影响，表明复杂速度模型捕获的可靠性越高，对所得体积信息的置信度就越大。