V.Maksymchuk1, ?.Orlyuk2, V.Korepanov3

Geomagnetic survey in Ukraine.

The geomagnetic survey was intensively made in Ukraine in last century. So, the aerial mapping with scale 1:200000 and more is accomplished for entire territory of Ukraine. For investigation of spatial structure of secular variations the network of 39 repeat stations have been set in 1972. Repeated observations on this network were done in 1974 and in 1985 using IZMIRAN's method. By this the components of magnetic field D, H and F were measured by discontinuous mode during 3 days at each point. For measuring D declinometer was used, for H - quartz magnetometer QHM and proton magnetometer - for F. The mean square error for D was estimated ~1', for H and F - ?2-3 nT. After the year 1985 no repeat stations measurements were made at all, that is why we don't know how many repeat stations could be revitalized again.
Concerning to magnetic observatories, geomagnetic observations are holding continuously at 3 magnetic observatories: Odesa, since 1936, Kyiv, since 1958 and Lviv, since 1952. All of them need modernization. At present time there are some hope to get new instrumentation in order to increase the measurements accuracy to necessary standards. Positive input for this is expected to get in frames of INTAS project CRENEGON (Co-ordinator - Dr. Jean Rasson, Dourbes observatory, Belgium). The main aim of this project is to upgrade some of NIS Geomagnetic observatories by new set of instrumentation developed at Lviv Centre of Institute of Space Research and Quantum Magnetometry Laboratory of Ekaterinburg University. The CRENEGON set of instruments includes LEMI-008 automated digital variometer with GPS reference and internal memory, LEMI-203 theodolite mounted DI-meter and POS-1 Overhouser magnetometer. Such relatively inexpensive instrumentation set will allow also to realize high precision measurements during repeat stations survey. Ukrainian team is expected to have one set of these instruments to the end of the year 2003 what will create the modern and accurate technical basement both for observatory and repeat stations measurements.