Development of a new technique of magnetic survey based on vector field measurement

研制了一种新的测量仪器--三分量磁通门流量计。该仪器可对地球磁场进行全矢量测量。该梯度仪由两个三分量磁通门磁力仪组成，它们沿垂直线相隔沿着50 cm。磁通门传感器采用坡莫合金环形磁芯。由于环形磁芯不会泄漏磁通量，因此可以最小化相邻传感器之间的干扰。该梯度计输出来自上部磁力计的地球场Bx、By和Bz及其梯度dBx、dBy和dBz。梯度的分辨率，单位为nT。地球磁场的数据可用作罗盘数据。该控制器可将4000点的数据记录在存储器中，并通过RS-232 C接口将这些数据传送到计算机。根岸基地（福岛县），大东窑遗址（福岛县），Tajiri网站（群马县），Saruta Kiln site（Gun-ma pref.），大寺山洞（千叶县），石形冢（静冈县），大千叶关寺遗址（静冈县），Zoubisan No.1 mounded tomb（Gifu Pref.），稻荷冢冢（京都），Kaibukiyama土墩墓（大坂府），Gyoujyazuka土墩墓（兵库县），Nanukaichi站点（兵库县），东山冢（兵库县），岩户山冢（福冈县），斋藤原（宫崎县）的隧道墓通过实验，证明了三分量梯度仪比常规仪器更有效，并提出了利用三分量梯度仪进行磁测的方法。

A new instrument, "Three-Component Fluxgate Gradiometer", was Developed. This instrument can make full vector measurements of Earth magnetic field. This gradiometer is composed of two three-component fluxgate magnetometers placed 50cm apart along the vertical line. A ring core made of permalloy is used on the fluxgate sensor. Since the ring core does not leak out magnetic flux, the interference between adjacent sensors can be minimized. This gradiometer outputs the Earth field, Bx, By and Bz from the upper magnetometer, and its gradient dBx, dBy and dBz. The resolution of the gradient in 1nT.The data of the Earth's field can be used as compass data. The controller can record 4.000-point data in the memory and send these sata to a computer through its RS-232C interface.A lot of sxperiments of field survey using this gradiometer were carried out at Ebisu-mori mounded tomb (Miyagi Pref.), Negishi site (Fukushima Pref.), Ooto Kiln site (Fukushima Pref.), Tajiri site (Gun-ma Pref.), Saruta Kiln site (Gun-ma pref.), O-terayama cave (Chiba Pref.), Ishinogata mounded tomb (Shizuoka Pref.), O-chiba pass temple site (Shizuoka Pref.), Zoubisan No.1 mounded tomb (Gifu Pref.), Inarizuka mounded tomb (Kyoto Pref.), Kaibukiyama mounded tomb (Osaka Pref.), Gyoujyazuka mounded tomb (Hyogo Pref.), Nanukaichi site (Hyogo Pref.), Higashiyama mounded tomb (Hyogo Pref.), Iwatoyama mounded tomb (Fukuoka Pref.), tunnel tombs in Saitobaru (Miyazaki Pref.) and so on.Through these experiments, it was proved that this gradiometer was more available than conventional instruments, and the procedure for magnetic survey using the three-component gradiometer has been also developed.