The state has given the Geological Survey of Estonia the task to accomplish geochemical research on Estonian crystalline basement rocks, for compiling a database on geochemistry of the crystalline basement and assessing the metallic-mineral potential of the basement rocks. Drilling operations are needed for this endeavour, with accompanying geophysical investigations. Also, modern geochemical studies have to be carried out on the rocks of the bored drill cores.
Altogether three drill holes will be bored in the exploration areas of Jõhvi magnetic anomaly and Uljaste polymetallic anomaly. As the geological survey does not possess technology for boring drill cores, an agreement was made on 9 September 2019 with the Engineering Bureau Steiger for carrying out the operations. According to the agreement, Steiger drills two holes in the Jõhvi exploration area, and one in the Uljaste exploration area, all three down to circa 700 m depth. The geologists of the Geological Survey of Estonia carry out the geophysical and geochemical research.
The head of the Department of Geological Resources, Tiit Kaasik: “After a break of 30 years we resume the exploration of mineral resources. The aim of the planned drillings is above all to verify the correctness of information from earlier drillings and achieve fresh material for making supplementary analyses with modern methods. The information collected with these operations makes it possible to provide more accurate estimations on the potential of these anomalies. Times have changed, and the accuracy of earlier studies is not sufficient today. In addition, all analyses were not made in the olden days. At that time, not all such elements were determined that have currently become interesting and may affect the value of these deposits. Unfortunately, it is not possible to use drill cores bored earlier for performing new analyses, as for the most part they have not been preserved.”
Drilling operations of the new drill holes start in October 2019. The choice of the exploration area based on the locations of earlier studies carried out by the Geological Survey of Estonia in each region and on detailed geophysical information.
