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Gem quality andradite‐rich garnet (IUC‐1), obtained from the Miocene trachyte dome near Ankara city (Turkey), has been identified as a potential natural secondary reference material for U‐Pb dating. In this study, U‐Pb dating was performed in five different laboratories using isotope dilution TIMS and laser ablation ICP‐MS to determine the homogeneity of euhedral garnet crystals. The U‐Pb ID‐TIMS data for IUC‐1 yielded 207Pb/235U and 206Pb/238U ages of 20.9 ± 0.4 and 20.6 ± 0.8 Ma respectively, and these values are consistent with U‐Pb LA‐ICP‐MS analyses, in which different garnet crystals yielded ages of 20.8 ± 0.1, 20.7 ± 0.1, 20.7 ± 0.2 and 20.2 ± 0.1 Ma. An andradite (IUC‐2) from the Serçeören wollastonite skarn (Turkey) can be used as a secondary reference material provided detailed imaging of the crystals is undertaken. ID‐TIMS data yielded 207Pb/235U and 206Pb/238U ages of 20.4 ± 0.4 and 20.9 ± 1.0 Ma respectively, and yielded U‐Pb ages on different grains of 20.5 ± 0.1, 20.7 ± 1.0, 20.8 ± 1.7 and 20.9 ± 1.6 Ma. The assigned weighted mean age of IUC‐1 (20.4 ± 0.5 Ma, 2s) is proposed as a 2023 reference value. IUC‐1 garnet is expected to contribute significantly to rapidly developing garnet geochronology in the near future.

Abstract. Solar storms and CMEs increase the amount of radiation that reaches the Earth and can perturb the magnetic shielding of the Earth. K and Kp indices quantify this perturbation by using magnetometers calibrated accordingly to the latitude of the geomagnetic observatory It is possible to contribute this measurement by establishing an observatory specialized in space weather studies. Many basic sectors are vulnerable against a strong solar storm unless necessary mitigation strategies are applied. Moreover, failure in taking an immediate precaution may have long-term effects which include economic destruction, irreversible health problems and weaknesses in national defence. In this work, the requirement such an observatory should have, the most 11 vulnerable sectors and corresponding mitigation strategies are discussed in detail. Turkey's seven geographical regions are examined to find the optimal location for the foundation of such a probable observatory. It is found that Central Anatolia is the ideal region and districts Konya/Karapinar and Konya/Çeltik are the possible candidates for such a location.