This research aims to identify the mineral rocks that are found in river village districts of Sumbermiri village, Lengkong district, Nganjuk regency. XRF tests have been conducted on a rock an result was 57 percent is calcite minerals. He method used geomagnetics, by measurig value total magnetic field area using magnetometer. Data collection done three times at each point, then retrieved data ...

There is a need to develop secular variation (SV) models using satellite data as the use of ground data is not always possible. Ground data has many limitations including limited data points and lack of data over ocean areas that are not easily accessible. Two regional geomagnetic field modelling techniques, namely polynomial surface modelling (PolyM) and Spherical Cap Harmonic Analysis (SCHA),...