Geophysical methods of prospecting were introduced in Poland in 1923, or at about the same time as in the Gulf Coast. In the first stage local seismic refraction and electrical surveys were employed for private mining and oil companies. The Mintrop's refraction method has shown success in locating extension of salt deposits near Wieliczka and in Wapno. The Sundberg electromagnetic method was not entirely successful in mapping some lead and copper ore deposits. The same refers to the use of electromagnetic methods for mapping of oil structures. Steep anticlines and complicated structures in which oil mostly occurs within the area of the Carpathian Range were not favorable to be worked out with these methods which were not entirely developed and proved at that time.