Rare metal concentration features at a caldera type deposit in the Miocene-Quaternary boron-lithium province of North America. Search for analogues

Abstract

The fact that lithium has a wide range of applications in many fields including the production of lithium-ion batteries determines an increased interest in lithium mining. The most common types of lithium raw material sources are underground brines, saline lakes (“salars”), and ore minerals. In 2021, the first and unique deposit of lithium clays was discovered in the McDermitt caldera (Nevada, USA). Its resources are estimated at 13.7 million tons of lithium carbonate with the lithium concentration of 2231 mg/l. The uniqueness of this deposit raises the interest in the formation of model ideas about lithiumclay genesis to search for analogous deposits and explore them. The purpose of the article is to provide an overview of the geological structure and describe the main development periods of the McDermitt caldera. The authors also characterize the potential sources of lithium (felsic igneous rocks and hydrothermal fluids), migration paths of lithium-bearing brines as well as the formation mechanism of clays with a high lithium content (hectorite, illite and smectite). A generalized formation model of this type of deposits is proposed. Particular attention is paid to the role of hydrothermal fluids as a potential additional source of lithium “supply” to the caldera basin. Key criteria characteristic of industrial accumulations of lithium of this type have been formed in order to explore and identify analogous deposits. In conclusion, the authors put forward a hypothesis about the presence of deposits that are analogous to the Thacker Pass in the McDermitt caldera in the lithium province on the Altiplano-Puna plateau in one of the calderas of the Altiplano-Puna volcanic complex, and in Eastern Kamchatka.