SIMULATION OF SHIP GENERATED TURBULENT AND VORTICAL WAKE IMAGING BY SAR

Synthetic Aperture Radar (SAR) imaging of ocean surface features is studied. The simulation of the turbulent and vortical features generated by a moving ship and SAR imaging of these wakes is carried out. The turbulent wake damping the ocean surface capillary waves may be partially responsible for the suppression of surface waves near the ship track. The vortex pair generating a change in the lateral flow field behind the ship may be partially responsible for an enhancement of the waves near the edges of the smooth area. These hydrodynamic phenomena as well as the changes of radar backscatter generated by turbulence and vortex are simulated.An SAR imaging model is then used on such ocean surface features to provide SAR images.Comparison of two ships' simulated SAR images shows that the wake features are different for various ship parameters.

四维储层监测的实用地球物理问题

四维地震监测是一种以时间推移方式、在一套产油储层上获得并分析重复的三维地震勘探结果的过程。四维地震技术在储层产油造成的流体饱和度、压力和温度变化方面具有直接成象能力。虽然四维地震的原理及概念比较简单,但是用其来解决实际问题却是很复杂的。利用 Chevron 公司在墨西哥湾、北海、西非和印度尼西亚等地四维地震项目的几个野外实例,讨论了5个主要的实用问题。促使四维地震发展的商业因素包括:通过作出所遗漏的石油图件增加产量;通过准确监测注入的流体降低作业费用;改进储层模型,降低勘探风险。可行性和风险评价是四维地震项目成功与否的关键因素。根据测井曲线和三维流体模拟,仔细地预测地震响应。地震采集和处理也必须进行优化,以便增强每次地震测量之间的可重复信号,并且降低非重复性噪音。最后,通过历史匹配流动模拟和油藏资料来重现四维地震图象,这是进行可靠储层管理决策的必要条件。