Oil company Royal Dutch Shell Plc said it has suspended operations at its Bajada de Añelo site in Argentina’s Vaca Muerta area after seismic activity in the region.

Shell, which operates the block along with local state oil firm YPF, said in a statement late June 5 that the preventative suspension of activities came after seismic movements were registered in an area of Argentina’s Neuquén province near the Andes mountains bordering on Chile.

“We are evaluating the information available and the evolution of the situation over the weekend to decide on Monday [June 8] how to continue. We will resume activities when we consider that conditions are appropriate,” Shell said in a statement.

Shell operates other areas in Vaca Muerta, a huge region of unconventional hydrocarbons including the Cruz de Lorena, Sierras Blancas, Aguila Mora, and Coirón Amargo Suroeste blocks. The firm did not mention any other suspensions.

Argentina’s oil sector has already seen production stall due to a nationwide lockdown and plunge in global demand due to the novel coronavirus pandemic.