The accident occurred at nine o'clock on Thursday morning at a depth of 900 meters.
The three geologists were Spanish men.
According to the mining company, the collapsed part was built only a few days ago.
Local authorities say the mine has undergone regular safety inspections – the most recent of which took place three weeks ago.
Catalonia's regional leader Pere Aragonès offers his condolences to the families affected by the tragic accident.
He also says that an investigation into the accident has been launched.
Two miners died in similar circumstances at the same mine about ten years ago.
Between 2016 and 2021, an average of four miners died annually in Spain.