新区、深层和深水等低勘探程度地区是今后油气勘探的重要方向,而烃源岩厚度预测则是沉积盆地勘探新区烃源岩评价的重要问题。以南黄海北部盆地勘探新区东北凹陷的烃源岩早期评价为背景,基于地震反射特征追踪东北凹陷内烃源岩的发育层位和空间展布研究成果,首次应用地震属性方法对东北凹陷的主力烃源岩(上白垩统泰州组和古新统阜宁组)厚度进行了初步预测,并结合地震速度岩性分析法对本区泰州组烃源岩厚度的预测结果加以验证。结果表明南黄海盆地东北凹陷泰州组烃源岩较阜宁组烃源岩分布广且厚度大,西次洼为东北凹陷主力生烃洼陷。地震属性法是沉积盆地勘探新区内定量化预测烃源岩厚度的一种行之有效的新方法,其对于类似盆地勘探早期的烃源岩评价研究也具有非常重要的借鉴意义。
New exploration areas, deep formation and deep water, which belong to the low exploration activity fields, are important for petroleum exploration. Prediction for the thickness of source rocks is critical to the source rock evaluation in new exploration areas in sedimentary basins. In the research context of preliminary evaluation on source rock of the northeast sag, which is the new exploration area in South Yellow Sea basin at present, this paper tries to trace the main formation and dimensional distribution of major source rocks in northeast sag based on the seismic reflection characteristics. The method of seismic attribution is applied for the first time to the prediction of the thickness of major source rocks (upper Cre- taceous Taizhou formation and Palaeocene Funing formation) in northeast sag, which is tested by the method of seismic velocity-lithology prediction to estimate the thickness of Taizhou formation source rock. We suggest that Taizhou formation source rock is widespread with larger thickness in northeast sag than Funing formation, and the west sub sag in northeast sag is the optimum hydrocarbon-generating sag. The method of seismic attribution has been proved to be a feasible and effective way for quantitative prediction on the thickness of source rocks in new exploration areas, and it also can be introduced to areas with simi- lar petroleum exploration conditions.