在科罗拉多、堪萨斯、得克萨斯及俄克拉何马的部分地区,早宾夕法尼亚世(莫罗期)的河道砂体含有区域性储层。在堪萨斯州的西南部,这些储层埋深一般为4000ft～5000ft(1200m～1500m),并且每口井约有0.15Mbbl～0.2Mbbl原油的控制储量,经济效益很高。储集砂层构成了海进期河谷充填层序的一部分,该层序沉积于切入下伏密西西比纪碳酸盐岩的河道内。充填厚度最大达60ft(18m),一般为10ft～30ft(3m～9m),沿河道厚度变化剧烈。因此,精细勾绘河道走向是很困难的。位于堪萨斯州芬妮县的斯图尔特油田就是这种储集类型的典型实例。最好的储集层存在于由潮汐改造作用形成的极细—细粒河道砂岩中。由于现有的二维地震及钻井资料无助于恰当地确定河道的方位,因此早期试图使油田向东扩展的努力失败了。在注水驱油开始之前进行的三维地震调查,有助于(1)查明现存干井之间河道的位置;(2)确定钻探能够成功的远景目标区。三维地震资料的进一步外推导致了一口干井,证实本区解释的局限性。因此,斯图尔特油田提供了勘探井间远景区时三维地震资料的能力及其局限性的一个重要实例研究。 In parts of Colorado, Kansas, Texas, and Oklahoma, river basins of the Early Pennsylvania (Moro- period) contain regional reservoirs. In the southwest of Kansas, these reservoirs are typically buried at depths of 4,000 ft to 5,000 ft (1,200 m to 1,500 m) and have controlled reserves of approximately 0.15 Mbbl to 0.2 Mbbl per well, providing high economic benefits. The reservoir sands form part of a seafill valley fill sequence that deposits in the channel cut into the underlying Mississippian Carbonate. Filling thickness up to 60ft (18m), usually 10ft ~ 30ft (3m ~ 9m), along the river thickness changes dramatically. Therefore, it is very difficult to finely draw the river course. The Stuart Field, in Fannie County, Kansas, is a prime example of this type of reservoir. The best reservoirs exist in the fine-grained channel sandstone formed by the tidal reformation. Efforts to try to expand the field eastward failed as the existing 2D seismic and drilling data did not help to properly determine the orientation of the channel. 3D seismic surveys conducted prior to flooding are instrumental in (1) identifying the location of existing channels between dry wells; and (2) identifying prospective target areas for successful drilling. Further extrapolation of 3D seismic data led to a dry well, confirming the limitations of interpretation in this area. As a result, the Stuart Field provides an important case study of the capabilities and limitations of 3D seismic data when prospecting cross-well prospects.