SBIR Phase II: A Novel Three-Dimensional Seismic Imaging Method by Migration to Common-Offset in Varible Velocity Media

9531316波波维西这个小型企业创新研究第二阶段项目将开发和测试计算软件，该软件以低得多的成本提供与全三维叠前偏移相同的精度。将叠前深度偏移应用于三维地震信息是当今石油工业面临的主要计算挑战。更便宜、更快的3D叠前成像方法可以在极其复杂的地质条件下开辟新的勘探场所，比如存在于美国西部逆冲地区和墨西哥湾盐层以下的地质条件。这种新的成像算法将地震数据偏移到横向变速地球上的共同炮检距，可以简化三维叠前深度偏移，减少计算次数，并克服了处理非常大的叠前数据体所带来的问题。这项研究工作的最终结果是向共炮检距(MCO)算法的迁移，该算法可用于处理两种主要类型的地震数据：海洋和陆地。对于海洋数据集，MCO沿着几个方位一致地堆叠数据，然后进行共同方位向偏移以进行最终成像。对于陆地数据集，MCO相干地堆叠预定数量的矢量偏移(固定方位和偏移长度)的数据，然后进行3-D Kirchhoff偏移以成像减小尺寸的数据集。新的MCO算法引起了石油公司和油田承包商的兴趣。该方法较好地圈定了油田构造，可用于油田勘探和油藏监测与描述。内部处理地震数据的石油公司和数据处理承包商都将从这种方法中受益，因为它允许以低得多的成本和更短的时间进行复杂的详细处理。

9531316 Popovici This Small Business Innovation Research Phase II project will develop and test computational software that offers the same accuracy as full 3-D prestack migration at a much lower cost. Applying prestack depth migration to 3-D seismic information is the main computational challenge facing the oil industry today. Cheaper and faster 3-D prestack imaging methods could open up new exploration venues in extremely complicated geological conditions such as those that exist in the overthrust region of the Western United States and below layers of salt in the Gulf of Mexico. The novel imaging algorithm migrates seismic data to a common offset in a laterally-variable velocity earth, and can simplify 3-D prestack depth migration, reduce the number of calculations, and overcome the problems associated with manipulating very large prestack data volumes. The end result of this research effort is a migration to common-offset (MCO) algorithm that can be used to process the two main types of seismic data: marine and land. For marine datasets, MCO coherently stacks data along several azimuths, and is followed by common-azimuth migration for final imaging. For land datasets, MCO coherently stacks data for a predetermined number of vector offsets (fixed azimuth and offset length) and is followed by 3-D Kirchhoff migration for imaging the reduced size dataset. The new MCO algorithm is of interest to oil companies and oil-field contractors. The proposed method better delineates the oil field structure and is used in oil exploration and reservoir monitoring and characterization. Both the oil companies that process seismic data in-house and the dataprocessing contractors would benefit from such a method because it allows sophisticated detailed processing at a much lower cost and over a shorter time frame.