AKIPRESS.COM - Workers at Rio Tinto's Oyu Tolgoi mine in Mongolia will spend Easter weekend evaluating the damage caused by a geotechnical incident at the copper, gold and silver mine, according to The Sydney Morning Herald.

The wall slip occurred in the open pit section of Oyu Tolgoi, which is in a remote section of the south Gobi desert.

Rio Tinto's exposure to the mine comes through its 51 percent stake in Toronto-listed miner Turquoise Hill Resources, which owns 66 percent of Oyu Tolgoi.

Turquoise Hill has not announced the incident to the market, and there have been varying views about the severity of the wall slip.

Though it is understood that no one was hurt, one Mongolian source said the wall slip was significant, particularly for a single mine company such as Turquoise Hill.

He said full-year guidance could be affected, and mine staff were understood to be working on a plan to recover sufficiently to avoid the impact on annual production guidance.

But a second source said the incident was a "bench scale failure", meaning it was smaller than a wall slide.

The second source said he was confident the incident would not affect Turquoise Hill's production guidance.

Under full-year guidance revealed earlier in March, Oyu Tolgoi should produce up to 195,000 tons of copper in 2016, and as much as 260,000 ounces of gold.

The incident came just days after the management of Turquoise Hill presented their March-quarter results, meaning investors may have to wait almost three months before getting a chance to ask management about the impact of the incident.