论文标题
由平方电流引起的磁电响应函数的变化
Variations in magnetotelluric response functions caused by Sq currents
论文作者
论文摘要
地球的磁铁（MT）响应被空间异质源场偏置。最近，即使在中纬度地区，局部源电流很少流动。这项研究的重点是由太阳静态（SQ）电流的焦点纬度变化引起的MT响应的变化。通过更改SQ电流的中心来计算60 s的MT响应。聚焦纬度的轻微变化会导致明显的电阻率和相位发生较大的变化。在安静的地磁活动期间，该中心在20-45 N的范围内变化，而在发生干扰时，该范围会变窄。即使这项研究仅考虑一个有限的情况，但结果表明，在安静的地磁活性时期阻抗的不稳定以及MT响应与地磁活性大小的相关性。结果，即使一个站位于纬度中部，也需要仔细处理阻抗，例如，通过检查电离层电流条件及其对地磁活性的依赖，例如，以延时MT的声音。
The magnetotelluric (MT) responses of the Earth are biased by spatially heterogeneous source fields. Recently, such biases have been reported even in mid-latitude areas, where localized source currents rarely flow. This study focuses on shifts in the MT responses arising from variations in the focus latitude of the solar quiet (Sq) current. The MT responses at 60 s were calculated by changing the center of the Sq current. Slight variations in the focus latitude cause large shifts in the apparent resistivity and phase. During periods of quiet geomagnetic activity, the center varies within a wide range of 20-45 N, whereas this range narrows when there are disruptions. Even though this study considers only a limited case, the results demonstrate the instability of the impedances in periods of quiet geomagnetic activity and a correlation of the MT responses with the magnitude of the geomagnetic activity. As a consequence, even when a station is located at mid-latitudes, the impedances need to be treated carefully for time-lapse MT soundings, for example, by checking the ionospheric current conditions and their dependence on the geomagnetic activity.
