Analysis of Metallogenic Differences in Magmatic Ni-Co Deposits in the East Kunlun Orogenic Belt, Qinghai Province: A Case Study of the Xiarihamu and Shitoukengde Deposits

Nickel and cobalt are essential minerals for the national economy, and technological development. With the rapid development of new energy vehicles, China's demand for nickel and cobalt resources has surged, with over 92% of nickel raw materials and 98% of cobalt raw materials relying on imports. This dependency poses significant security risks to the supply of mineral resources, directly threatening national security. Therefore, it is urgent to enhance the understanding of the metallogenic regularity of nickel and cobalt deposits domestically and to find new resource continuation areas. China's limited sources of nickel and cobalt differ significantly from the rest of the world, with 93% of nickel resources and 45% of cobalt resources coming from magmatic nickel-cobalt sulfide deposits. Thus, magmatic nickel-cobalt deposits are the most important type of deposits for achieving resource exploration and reserve increase in China. The East Kunlun orogenic belt in Qinghai Province hosts numerous mafic-ultramafic intrusions, offering favorable metallogenic geological conditions and resource potential, indicating great prospects for exploration. However, despite sharing the same metallogenic background and similar metallogenic characteristics, the Xiarihamu and Shitoukengde deposits exhibit significant differences in ore quality and orebody scale. One is a super-large deposit with high grade (1180 thousand tons Ni@0.68%), while the other is a large deposit with lower grade (120 thousand tons Ni@0.44%). This disparity greatly restricts the exploration and new breakthroughs in nickel and cobalt resources. This paper systematically reviews the metallogenic characteristics, ore-controlling conditions, metallogenic processes, and exploration potential of the two deposits, revealing that assimilation is the key process leading to sulfide segregation and the formation of nickel-cobalt deposits. The differences in the degree of assimilation and the sulfur content of the surrounding rocks are the direct causes of the significant metallogenic differences between the two deposits. Furthermore, it is pointed out that the mafic-ultramafic intrusions in the ancient gneiss surrounding rocks are the key direction and space for achieving new discoveries in nickel-cobalt exploration. This can support and serve the new round of strategic actions for exploration breakthroughs, enhancing the capability to secure nickel and cobalt resources.