The new zone is approximately ten kilometres north of the Ivanhoe Mines Oyu Tolgoi copper-gold mining complex and is currently under construction.
The discovery, known as Ulaan Khud North, extends by an additional three kilometres to the north to more than 23 kilometres, half of which has been extensively drill-tested to date.
An ongoing exploration program including proprietary, induced-polarization (IP) technology has identified additional exploration and development targets.
Ivanhoe Mines executive chairman and chief executive officer Robert Friedland said the with the new discovery offers potential to discover new porphyry deposits, rich in copper and gold.
BHP Billiton has 50% stake in the JV and has spent $8m in exploration costs and conducting an airborne survey using the proprietary Falcon(TM) gravity gradiometer system over the Oyu Tolgoi area.
The pre-mining agreement for the Ulaan Khud North property specifies that Ivanhoe and BHP Billiton have three years to conduct additional exploration, complete an environmental impact study, prepare a final feasibility study and gain approval for the design for the project.
The agreement also specifies that a technical and economical study to mine the deposit is required to be delivered to the Mineral Resources Authority of Mongolia (MRAM) by June 30, 2013.
Ivanhoe Mines vice-president, exploration Richard Gosse said the three year pre-mining agreement will allow the company to prepare resource, technical and economic studies and to obtain all necessary mining permits and approvals.