Sabba S. Ștefănescu  Sabba S. Ştefănescu (20 July 1902 – 15 April 1994) was a Romanian geophysicist, professor of geophysics, member of the Romanian Academy. He was the cofounder, together with Liviu Constantinescu, of the Romanian school of geophysics. He was the third and youngest son of Sabba Ștefănescu, professor of paleontology at the University of Bucharest, and of his wife Constanţa. He received at first a private education, then visited for a couple of years the college St Sava in Bucharest, but left the country together with his family in 1917 for Paris, where his father had to accomplish a diplomatic mission. He obtained there his baccalauréat at the Lycée Saint-Louis and was admitted as a student at the prestigious École des Mines, from which he graduated in 1923. He returned subsequently to Romania, where he worked for some time in the mining district of the Jiu Valley. In 1927 he joined the Geological Institute of Romania, where he began his studies in electrical prospecting, which was to remain his lifelong preoccupation. Two short papers of his drew the attention of the brothers Conrad and Marcel Schlumberger. They were at that time the pioneers of this field in Europe and had just founded the geophysical prospecting company bearing their name, which has developed since into the world leading Schlumberger Limited. Ştefănescu entered into a direct collaboration with them and spent the years 1929-1933 in Paris, a period which he considered to be the most fruitful of his scientific life. He returned to Romania in 1933 and resumed his work at the Geological Institute, being at the same time a consulting engineer of the Schlumberger company. He received a doctor's degree in physics from the University of Bucharest (1945), was elected a corresponding member of the Romanian Academy (1946) and became head of the geophysical department of the Geological Committee (1950) and of a new Department of Geophysics at the Institute for Mining in Bucharest (subsequently transferred to the Institute for Oil, Gas and Geology); he retained these positions until his retirement in 1967. One may say that over that period the first generations of Romanian geophysicists were formed; he made an essential contribution to this. He was elected a full member of the Romanian Academy (1963) and president of its Section of Geological, Geophysical and Geographical Sciences (1966-1990).