드론을 이용한 신뢰성 있는 항공자력탐사 수행을 위해서 자력탐사 시스템과 드론 시스템을 구성하여 철광산 지 역 자력 탐사에 적용하였다. 드론에 실리는 자력탐사 시스템은 Bartington사의 플럭스게이트 자력계 Mag639를 센서로 사용하고, A/D convertor를 이용하여 태블릿PC에 자력값이 저장되도록 구성하였다. 드론의 비행 컨트롤 모듈로는 확장 성이 좋은 Pixhawk를 사용하였고, 적재 중량(Payload) 3 kg, 최대 중량 적재 시 15분 동안 비행이 가능하도록 구성하였 다. 드론의 자기장 간섭 범위 측정 실험을 통해 드론에 의한 자기장 간섭효과를 제거하였고, 정확한 위치 정보 확보를 위해 RTK GPS를 적용하였다. 정확한 위치정보를 토대로 동일한 측선에 대해서 고도를 변경하여 두 번 측정해서 자력 변화율 자료를 확보하였다. 또한 지형 정보를 사용하여 지형을 따라 비행하는 비행경로를 설정함으로써 지형 효과를 없 앨 수 있었다. 드론 기반 항공자력탐사 시스템을 통해 획득된 자력자료는 Geometrics사의 핵자력계 G-858을 이용해 동 일 지역에서 획득한 자료와 양상이 일치함을 확인하였고, 이를 통해 드론 기반 항공자력탐사 시스템을 이용한 탐사 자 료에 대한 신뢰성을 확보할 수 있었다.

A magnetic survey was carried out at the Barton Peninsula in King George Island, Antarctica. To analyze geological features in the study area, several filtering methods in 2-dimensional wavenumber domain were used. The Barton Horst associated with volcanic activities is well revealed on the low-pass filtered anomaly map. Possible existence of small volcanic plugs or, presumably, mineralized zones are apparent at northern parts and south-western part by reduction-to-the-pole and pseudo-gravity filtering. On the 1st vertical derivative and directional filtered anomaly maps, the geological boundaries on the surface are well identified, and fault strikes along E-W or NW-SE direction appeared to be mostly dominant throughout the study area. Density and susceptibility mapping were performed using the inversion method. The apparent densities of tuffaceous rocks distributed in the southern parts and those of quartz-diorite or crystal tuff in the northern parts were computed as values up to about 2.69 g/㎤ and 2.73 g/㎤, respectively, and the apparent susceptibilities of those rocks are appeared to be about 250 × 10^(-6) CGS and 1870 × 10^(-6) CGS, respectively. These results are in accordant with those of samples measured by Garrett(1990). Therefore, it is concluded that the studied area of the Barton peninsula has been influenced by crustal movement associated with active volcanism and the surface lithology is extended to the considerable depth.

The offshore magnetic data were analyzed to determine the depth of magnetic basement of Kyungi-bay. The mean depth to the basement was computed by a power spectral analysis method. To determine the relief of magnetic basement, the total magnetic intensity data were first reduced to the pole and transformed to a pseudo-gravimetric anomaly data using the Poisson's relation. The relief of basement was estimated from the downward continued pseudo-gravimetric anomaly data to the mean depth. In the process of data preparation, Tuckey and Harming filter was used to suppress the near surface effect of short wavelength. A band-pass filter was also applied before downward continuation. From the result of this study, it is appeared that the magnetic basement rock is ccmposed of mainly granite gneiss and depth to the basement rock is varied from 300m to 500m. The relief of magnetic basement is appeared to reflect the general topography in this area.