南得克萨斯地区Webb县Gold River North油田上白垩统Olmos组地震沉积学

Seismic sedimentology in the Olmos formation of upper Cretaceous, Gold River North Oilfield, Webb County, south Texas

利用三维地震资料和测井资料，结合90°相位和地层切片技术，对美国南得克萨斯地区Webb县Gold River North油田上白垩统Olmos组进行地震沉积学研究，识别出9个四级层序。研究结果表明：研究区90°相位地震资料振幅与岩性测井曲线能较好地对应，对地震资料进行90°相位转换后可以通过地震振幅分析岩相；地层切片技术能更精确地反映研究区等时的沉积分布特征，结合岩性测井资料可以较准确地分析沉积体系；Olmos组可以识别出一套河流-三角洲沉积体系，包括前三角洲亚相、三角洲前缘亚相、三角洲平原亚相、曲流河相和下切谷沉积等。

By using 3D seismic and logging data, seismic sedimentology was studied in Olmos formation of upper Cretaceous, Gold River North Oilfield, Webb County, south Texas, and nine fourth order sequences were identified with the technique of 90°-phase data and stratal slices. The results show that seismic amplitudes can be correlated to log lithologies by using 90°- phase seismic data and used to analyze lithofacies. The technique of stratal slices can reveal the isochronism of sediment dispersal patterns with high-resolution. And the sedimentary systems can be analyzed with lithologic log data. A shelf-edge deltaic system including fluvial plain, deltaic plain, deltaic-front, prodelta, and incised valleys was identified in Olmos formation of Gold River North Oilfield.