Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow, Russia:

E. N. Slyuta, Head of Laboratory, Candidate of Geologo-Mineralogical Sciences, slyuta@mail.ru

The aim of the article is to give a brief review of the major problems connected with the determination of basic types of Moon’s resources, conditions of their occurrence and spread in the regolith of the Moon and appraisal of possible reserves. It is shown that the most promising Moon’s resources are either concentrated in the regolith, or occur in the regolith in the enriched condition ready for the extraction. The scope of the review embraces the structure of the lunar regolith and various methods to estimate its thickness, which can be used in combination depending on the objective to be reached. Each method has a certain area of estimation. It is also shown that the drilling depth down to 15 m is suffi cient across the nearly entire Moon’s surface and provides an ample stratifi ed geological column of the regolith starting from the base rock formation. All extraterrestrial resources are divided into two basic categories. The fi rst category includes resources required for the industrial use on the spot. The second category of the extraterrestrial resources are the materials, crude or elements that are in defi cit or absent on the Earth, and their extraction and shipment to the Earth can be profi table. Under discussion are volatile gas components that are divided into three basic types depending on the mechanism of retention and the form of occurrence in the regolith – implanted, loosely bound and frozen volatile matter. Implanted gases are resistant to mechanical impact and temperature in the range of several hundred degrees. Weakly bound gases that pervade pore space of the lunar regolith, on the opposite, readily escape under thermal and mechanical attacks on the regolith. Frozen volatile gases are in open pore space of the lunar regolith and are intolerant relative to mechanical and temperature effects. The article shows that extraction of weakly bound and frozen volatile matter featuring weak concentration and availability is impossible using the classical technology of excavation, transportation and heating of the lunar soil. In the capacity of the most promising technology for the development of the Moon’s resources, the controllable selective extraction of gases from the natural and industrial silicates using electromagnetic resonance is considered.
The studies have been supported by the Russian Science Foundation, Grant No. 17-17-01279.

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