Estacion magnetica en la base antartica espanola Juan Carlos I

A geomagnetic observatory is intended to start its operations during the 1996-1997 season at the Spanish Antarctic station Juan Carlos I. The station is located at Livingston Island, in the South Shetland Islands, and the observatory was placed at 62° 39' 44'S, 60° 23' 41'W (52° 6' 15'S, 8° 12' 40'E Geomagnetic, 19.4 m a.s.l. With the above objective in mind, on one hand, during the 1995-1996 season the huts that will lodge the magnetic observatory were deployed; on the other hand, both the variometric station and the instruments for the absolute measurements of the geomagnetic field were verified at Ebro Geomagnetic Observatory. In this paper we describe the criteria for the selection of both the most appropriate site and the most suitable magnetic station, its characteristics, the method for the measurement of both the field variations and the absolute observations, the software designed for the data analysis, a general evaluation of the results and the future perspectives. The magnetic observatory is based on an automatic vector magnetometer, in which a proton precession magnetometer, acting as the magnetic sensor, is adequately exposed to bias fields by means of two mutually perpendicular pairs of Helmholtz coils. When deployed, the coils are aligned to measure changes in declination (D) and inclination (I) (δD/δI configuration), and total field (F). Absolute measurements will be independently taken with the combination of a fluxgate theodolite (often called DI-flux because D and I are determined using the instrument) and an extra proton magnetometer. The continuous records that this observatory will provide will be very useful for any kind of geomagnetic study and, specially, as a reference level to correct magnetic surveys in the South Shetland Islands - Antarctic Peninsula region, as well as to study volcanomagnetic effects in Deception Island.