Agostina Montaño, a CNN en Espanol reporter based in San Juan, reported a “strong” quake which knocked everything off the shelves in his home.
According to preliminary data from the Pacific Tsunami Warning Centre (PTWC) the earthquake struck at a depth of about 12.5 miles.
However, the centre added there is no tsunami warning at this stage.
There are no reports of any casualties thus far.
The initial earthquake was followed by a number of powerful aftershocks.
Around 20 minutes after the first quake a 5.0 magnitude aftershock hit south-west of Nueve de Julio, about 620 miles from the original tremor.
This was followed by 4.9 and 5.3 magnitude aftershocks.
The earthquake was also felt over the border in Chile including in Santiago, the nation’s capital.
A number of people in the affected area used social media to describe the event.
One Chile based woman tweeted: “So the earthquake was a M6 [magnitude six] in Mendoza, Argentina?
“We felt it in Santiago, and it was really long!!!
“My bedroom lamp is still moving.”
Another Twitter user based in Buenos Aires noted they didn’t feel the quake in the Argentine capital.
They tweeted: “Yes, there was an earthquake on Argentina but I’m fine: it was in a different place so I didn’t even notice it.
“I hope that people from San Juan are ok.”
Western Argentina is situated on the Circum-Pacific Belt, or ‘Ring of Fire’, an area around the Pacific where a number of tectonic plates meet known for its frequent earthquakes and volcanos.