Successful Conclusion of the GICA 2026 Erdenet Porphyry Cu-Mo District Geological Excursion
ULAANBAATAR — The Institute of Geology at the Mongolian Academy of Sciences, alongside the Erdenet Mining Corporation, has successfully concluded a two-day geological field excursion to the world-class Erdenetiin Ovoo copper-molybdenum deposit. Held from September 13–14, 2026, this field program served as a premier pre-conference event for the International Conference on Geological Issues of Central Asia (GICA 2026). The trip was led by a distinguished team of experts: Dr. Ariunzaya Tsogoo, Head of the Mineral Resources and Metallogeny Sector at the Institute of Geology, Mongolian Academy of Sciences, and Dr. Altankhuyag Dorj-Yunden, Chief Geologist of the Erdenet Mining Corporation SOE and Associate Professor.
Unlocking the Selenge Terrane and Regional Stratigraphy
The geological route began on September 13 with a field inspection of the Orkhon–Selenge volcano-sedimentary trough. Participants examined the Permian–Mesozoic volcanic-plutonic belt, which records the successive stages of volcanism and magmatism associated with the historic closure of the Mongol–Okhotsk Ocean. Outcrop stops allowed the group to discuss the regional tectonic settings of the hosted Late Permian–Early Triassic Selenge Intrusive Complex before arriving in Erdenet City for an evening geological networking session. Deposit Alteration and Lithocaps on September 14, the focus shifted to the localized mineralization controls within the Erdenet ore district.
Erdenet Open Pit Mine
At the active mining face, geologists observed high-grade quartz-muscovite alteration assemblages, D-veining, and structural fault networks cutting the host granodiorites.EMC Digital Museum: The group reviewed the 40-year history of geological exploration and discovery at the deposit since its initial mapping in 1964.Tsagaan Chuluut Lithocap: The excursion concluded at an extensive 10 × 2.5 km advanced argillic alteration zone located 2 km northeast of the pit. Geologists inspected exposures of residual quartz, K-alunite, diaspore, and pyrophyllite. Discussions focused on geochronological data showing that this high-sulfidation epithermal environment overprinted the primary Middle Triassic porphyry mineralization approximately 16 million years later, proving a separate, younger magmatic-hydrothermal event.
