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SUMMARY Lavas of Pliocene–Quaternary age were sampled in the South Harghita Mountains, which form the southern end of the Călimani–Gurghiu–Harghita volcanic chain of the East Carpathians. The analyses of 68 volcanic sites in the South Harghita Mountains provided 62 sites with well‐constrained directional data (n > 5 and k > 50) in an age interval ranging from 0.5 to 4.3 Ma. The age and polarity for the 62 sites (38 normal and 24 reversed) are consistent with the Geomagnetic Reversal Time Scale and support the model of the southward migration of the volcanism. The distribution of the VGPs is Fisherian and the mean pole position, both from all contributing sites and from the 53 sites older than 2 Ma, includes the spin axis. This result is consistent with the absence of important vertical axis rotations after the emplacement of the volcanic rocks in agreement with tectonic models for the Pliocene–Quaternary evolution of the bending area of the East Carpathians. Virtual geomagnetic pole dispersions are consistently high compared with global values obtained between 40 and 55°N, but closer to the values obtained only from the Time Averaged geomagnetic Field Initiative studies for the same latitudinal band. Our data are compatible with the prediction of the statistical palaeosecular variation model TK03. The inclination anomaly is less than 1° in accord with the Total Average Field global data. These palaeomagnetic data from the South Harghita volcanic rocks are the first data from the southeastern Europe which can be considered in the databases for time averaged field and palaeosecular variation from lavas analyses in the last 5 Ma.

Investigations of the paleosecular variation of the geomagnetic field on geological timescales depend on globally distributed data sets from lava flows. We report new paleomagnetic results from lava flows of the East Carpathian Mountains (23.6°E, 46.4°N) erupted between 4 and 6 Ma. The average virtual geomagnetic pole position (76 sites) includes the North Geographic Pole and the dispersion of virtual geomagnetic poles is in general agreement with the data of the Time Averaged geomagnetic Field Initiative. Based on this study and previous results from the East Carpathians obtained from 0.04–4 Ma old lava flows, we show that high value of dispersion are characteristic only for 1.5–2.8 Ma old lava flows. High values of dispersion during the Matuyama chron are also reported around 50°N, in the global paleosecular variation data set. More data are needed at a global level to determine if these high dispersions reflect the behaviour of the geomagnetic field or an artefact of inadequate number of sites. This study of the East Carpathians volcanic rocks brings new data from southeastern Europe and which can contribute to the databases for time averaged field and paleosecular variation from lavas in the last 6 Ma.

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