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在德克萨斯西部碳酸盐岩油田获得的高频井间地震数据证明了运用大井距技术的可能性。在这一试验中采用了压电弯曲机震源。在井距为1500英尺以上,深度范围为7700到9600英尺的情况下采集的两个井间剖面表明,数据的质量显然与场地有关。接收位置的随机噪音级似乎是最主要的控制因素。试验期间所用的三口井中的噪音级和噪音特征是非常不同的。衰减和传输损失似乎也大大影响数据的质量,在有许多薄页岩层的层段记录不到有用的数据。在大阻抗差界面上出现传输损失,它限制了测量的孔径。资料的分析和处理结果表明:横向不均匀性和速度各向异性使人们难以确定与反射成像相称的速度模型。在这种条件下估算速度模型并将此准确地应用于成像的稳妥方法是对现行的井间反射成像技术作必要的改进,这对大井距测量尤为重要。
High-frequency cross-well seismic data obtained in the western Texas carbonate oilfield demonstrate the potential of using large well spacing technology. Piezoelectric bending machines were used in this experiment. The cross-section of two wells collected at a well spacing of 1,500 feet and a depth range of 7,700 to 9,600 feet shows that the quality of the data is clearly site-dependent. The random noise level at the receiving location seems to be the dominant control factor. The noise levels and noise characteristics of the three wells used during the experiment are very different. Attenuation and transmission losses also seem to greatly affect the quality of the data, with no useful data recorded in layers with many thin shale layers. Transmission loss occurs at the large impedance difference interface, which limits the measured aperture. Data analysis and processing results show that: lateral and velocity anisotropy makes it difficult to determine the velocity model commensurate with the reflection imaging. Estimating the velocity model under such conditions and applying it accurately to imaging is a necessary improvement over current crosswell imaging techniques, which is particularly important for large well spacing measurements.