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本文分析了美国Hartzog Draw气田4106井、Katie 1井和20-11井等3口井上自垩统Shannon储层AVO属性参数，Shannon层段在4106井处为21 m厚的含气砂岩；在Katie1井处为6．5 m厚非储层(干层)；在20-11井处为8．5m厚含水砂岩。通过分析3口井资料作出Shannon层段顶面反射系数与入射角之间的关系图和有关AVO属性参数的交会图，研究了不同岩性、不同流体性质的Shannon层段的AVO异常地质属性特征，得出结论：不同的AVO异常代表了不同的地质属性特征，含气砂岩具有较明显的AVO异常，由于其泊松比明显下降，AVO斜率一般为负值；含水砂岩由于其泊松比增加，AVO斜率一般为正值。非储层(干层)砂岩其泊松比与围岩相近，AVO异常不明显。由此认为AVO的有关属性参数的研究可以为含气砂岩的定量化描述提供准确依据。最后建议：①为防止结论的片面性，在进行AVO异常地质分析时，要利用最多的测井资料进行正演模拟分析；②为了更好地开展AVO的反演研究，有必要分别建立含气层、含水层和干层的AVO模型。“,”Through analyzing AVO attributive parame ters of Shannon reservoir, Upper Cretaceous,in three wdls,i, e. wells 4106, Katie- 1 and 20-11, in Hartzog Draw gas field, U. S. A. ,it is shown that the Shannon reservoir in well 4106 is a gas bearing sandstone with a thickness of 21 m; the ope in well Katie-1 is a non-reservoir (dry sandstone)with a thickness of 6.5 m;and the one in well 20-11 is a water-bearing sandstone with a thickness of 8.5 m. On the basis of analyzing the data from the three wells, the relation between the reflection coeffi cient of the top of Shannon reservoir and its incident angle and the crossplot of relevent AVO attributive parameters are made up and the geological attributive features of AVO anomalies in Shannon reservoir intervals with different lithological properties and different fluid characteristics are studied in the paper. It is concluded that different AVO anomalies represent different geo logical attributive features, i. e. the gas-bearing sandstone is of relatively obvious AVO anomaly, because its Poissons ratio sig nificantly decreases and the slope of AVO is negative generally; because the Poissons ratio of the water-bearing sandstone in creases, the slope of its AVO is commonly positive;and because the Poissons ratio of the non-reservoir(dry sandstone)is near to that of its adjacent rocks, its AVO anomaly is unclear. Therefore the research on relevent AVO attributive parameters may pro vide a reliable basis for quantitatively describing gas-bearing sandstone. Finally, two suggestions are proposed as follow s: ①in order to raise the accuracy of the quantitatively description, maximum logging data must be applied to the forward modeling analysis, when the geological analysis of the AVO anomalies is being done;②in order to well carry out the research on AVO inversion modeling, it is necessary to set up the AVO models of the gas-bearing sandstone, water-bearing sandstone and dry sandstone respectively.