A COMBINATION OF GRAVITY AND SEISMIC REFRACTION MEASUREMENTS, APPLIED TO GROUNDWATER EXPLORATIONS NEAR TALTAL, PROVINCE OF ANTOFAGASTA, CHILE*

In northern Chile, which is part of the Atacama Desert, groundwater supply and storage are controlled by deep structural phenomena. Several geophysical exploration techniques were used to determine the structure and depth of the basement of a broad valley filled with unconsolidated alluvial deposits. The gravity method was applied to obtain a general picture of the basement. This was followed by seismic refraction measurements along two traverse lines which appeared to be of major interest. Additional experiments with the magnetic and the telluric methods supplemented the geophysical investigations.

In this paper the results of the different geophysical methods are presented, compared, and evaluated with respect to the usefulness in arid regions.

It is concluded that a complementary use of the gravity method and the seismic refraction method is a very fruitful and efficient approach for the geophysical reconnaissance of water‐bearing basins in flat and arid zones like the Atacama Desert.