A screengrab shows Argentina. A quake struck 138 km northeast of Salta on Oct. 6, 2011.
There were no immediate reports of damage after a 6.2-magnitude earthquake shook northern Argentina on Thursday, police and local authorities said.
The quake was located 139 km northeast of Salta, said the U.S. Geological Survey, revising the magnitude up from an initial reading of 6.0. The quake struck at a shallow depth of 9.5 km, it added.
An official at the world's biggest copper mine, Escondida, in the north of neighbouring Chile, said workers did not feel the tremor.