沈昭昂,彭中,杨波

• 1:浙江大学地球科学学院

摘要(Abstract)：

海底大地电磁观测常受到海洋潮汐、内波或湍流的干扰，为了提高大地电磁数据观测的可靠性，有必要研究洋流运动的感生电磁场对海洋大地电磁观测的影响。本文从麦克斯韦方程组出发，推导了海水运动产生的感应电磁场控制方程，并基于有限体积法计算了包含海水层且考虑了洋流运动的感生电磁场效应的大地电磁响应。同时，以简单洋陆模型和卡斯卡迪亚俯冲带模型为例，对大地电磁响应进行了三维数值模拟。结果表明：观测信号周期越短，靠近洋流活动区域的海底大地电磁场受海水运动的干扰越严重，视电阻率失真现象越明显；陆地一侧的大地电磁场因感生电磁场的快速衰减而几乎未受到海水运动的影响。因此洋流的电磁效应对于海底观测台站会产生较大的干扰，而对陆基台站的观测所带来的影响可以忽略。

关键词(KeyWords)： 洋流;电磁效应;大地电磁正演

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(编号：41830212)

作者(Author): 沈昭昂,彭中,杨波

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