寻找氦资源的新思路及初步实践

Helium resources have irreplaceable applications in many high-tech fields such as aerospace, medical treatment, and basic physics research. Thus, helium resources have become an important strategic material to win future scientific and technological competition. Currently, the main international helium exporters are the United States, Russia and Qatar. For a long time, China has been regarded as a helium-poor country, and the helium resources mainly rely on imports. Helium has become one of the potential risk factors in China's future high-tech development, and it is urgent to find new solutions. Through the analysis of the physical and chemical properties of helium, it can be seen that helium can only exist as a gas state after being produced by nuclear fission inside the Earth. As the most inert gas, helium does not react with any other elements. Therefore, helium is not associated with other compound gases, such as natural gas (CH₄), CO₂, H₂S, etc. Besides, helium has a molecular weight of 4 or 3, which is only heavier than hydrogen (molecular weight is 2). As the lightest gas, helium tends to get rid of the constraints of the Earth's gravity. Thus, helium tends to accumulate in a dome-shaped stratum structure with higher altitude and good sealing characters, rather than a region with a basin structure. In previous studies, people have always believed that helium and natural gas have an accompanying relationship. Therefore, many geological theories of searching for helium gas often focus on the basin area. Here in this work, we propose a new theory on the migration and accumulation of helium, which indicates that the Tibet Plateau is expected to find helium resources with exploitable value. In June 2021, our team members went to Tibet and collected the gas in the hot spring. In order to ensure the purity of the gas, we use the drainage method to collect the gas from the hot spring. This method can avoid pollution caused by gas components in the air. By using a high-resolution mass spectrometer, we analyzed the gas composition in the hot springs in Tibet. All the gas samples from hot springs are detected with high concentration of helium, which is a good verification of the new-proposed model. The air in Beijing and Tibet was used as a reference sample, and the mass spectrometry measurement was also carried out, but no signal of helium gas was found. The concentration of helium in the hot springs in Tibet is comparable to the concentration of helium in the Hetian River gas in the Tarim Basin. The higher concentration of helium in the Qinghai-Tibet Plateau is worthy of further exploration. This point of view breaks the previous habit of thinking that the search for helium must be in the basin area. The plateau area provides a new option for searching for helium gas. It is of great significance for China to solve the shortage of helium resources and external dependence, and will also give a huge boost to the development of other scientific and technological fields in China.