Title

V.L. MASAITIS (VSEGEI)

Geological map compiling of impact structures

Paper discusses the issues associated with displaying on the State Geological Maps of ancient space­borne impact structures sometimes encountered in certain regions. Their diagnosis is based on a study of necessary and sufficient, mainly lithologic and petrographic evidence of impact metamorphism. Selection of different types of impactites and impact breccias and their associations as mappable units is based on a combination of data on material composition, structures, and textures of rocks and the structure of bodies they form. Impact structures are shown on maps of minerals, as they contain deposits of various raw materials, sometimes very large ones.
Keywords: geological mapping, impact structure, astrobleme, coptogenic rocks, impactites, impact breccias.