Geomagnetic Observatory, 75 years old: achievements and


Isac, A. (1), Matzka, J. (2), Iancu, L. (1)

(1) Geological

institute of Romania, Bucharest, Romania, (2) GFZ German Research

Centre for Geosciences, Potsdam, Germany


The presentation focuses on main aspects of

the last seventy five years (1943-2018) of Surlari observatory, IAGA

code: SUA. Since beginning until 1995, it operates continuously

classical sets of photographic magnetographs Askania and Mating &

Wiesenberg from Potsdam. The last one was combined with four Bobrov

variometers for H, D, Z and F values of magnetic field. To find out

the baseline values for all magnetograms, the absolute measurements

were carried out by means of a magnetic theodolite Mating & Wiesenberg

for D and H, an oscillation box Askania for H, an earth inductor

Mating & Wiesenberg for I, a Varian proton magnetometer for F and an

ELSEC vector proton magnetometer for Z and F. Since 1989 Surlari

operated for the first time a digital magnetic recording system

DIMARS. Beginning with 1998 a new digital recorder system-Bartington

MAG-03MC with MAG-03DAM data logger for XYZ was currently in use. The

absolute measurements were carried out by means of the THEO 010B with

Bartington MAG-01H D/I Fluxgate and Varian proton magnetometer for F.

At that time Surlari observatory become an IMO. Then, during 2006-2008

periods, the magnetic laboratories and the variometer room were

repaired and the observatory was equipped with a Geometrics proton

magnetometer G-856 for absolute measurements. Only in 2009 GFZ German

Research Centre for Geosciences decided to support our observatory by

installing a new digital equipment: a three-axial fluxgate

magnetometer FGE, a data logger MAGDALOG, developed at Adolf Schmidt

observatory, Niemegk, GPS receiver and an Overhauser proton

magnetometer GSM90. In 2014, the second identically recording system

(FGE and Overhauser magnetometers), was delivered by GFZ, as backup

system. With this upgrade, a long tradition of cooperation, over two

centuries, between Potsdam/Niemegk and Surlari has been continued. In

this way, a long-term geomagnetic observatory with real-time data on

INTERMAGNET web site, and with the status of an IMO has been

accomplished. Our future challenges are to keep constant the

temperature of fluxgate sensors as well as their electronic parts in

order to obtain the accurate baseline values of the variometers and

to improve, together with Romanian ROMATSA experts, aeronautical and

airport safety on Romanian territory.