Based on structural and textural features of rocks of volcanogenic-sedimentary strata, their mineral composition, genesis and secondary transformations, 11 petrological types of rocks are identified in the article. Regularities of changes in their chemical, mineral composition, filtration-capacitive properties, mineral and bulk density, acoustic and electrical properties, natural radioactivity and nuclear-physical parameters depending on genesis and secondary transformations have been studied. The need to take into account the identified patterns in geological interpretation of results of well logging is shown. Porosity and permeability increase in sequence: lava of massive texture – lava with voids – volcanic-sedimentary – volcanoclastic rocks. The influence of secondary transformations can both improve and worsen the permeability and capacitance characteristics. The mineral composition of the studied deposits is represented by quartz, potassium feldspar, plagioclase, chlorite, illite, mixed-layer formations, calcite, siderite. The content of quartz, potassium feldspar in naturally reduced from acidic differences to ultramafic. With an increase in the content of dark-colored minerals, the content of chlorite and calcite increases. Secondary processes contribute to the reduction of feldspars as result of their destruction and replacement with post-magmatic minerals. Variations in mineral composition have a significant impact of the density, acoustic and nuclear-physical characteristics of the studied deposits. The electrical resistance of rocks (in addition to porosity and water saturation) depends on the structure of the void space and secondary transformations. Fracturing, clay minerals, zeolites, pyrite reduce electrical resistance. The reduced absorption capacity increases with an increase in clay content from volcanogenic to volcanogenic-sedimentary and sedimentary rocks. The total radioactivity and content of potassium, uranium, and thorium decrease in a series: acidic volcanogenic rocks – volcanogenic-sedimentary deposits – sedimentary deposits - mafic volcanogenic rocks. In acidic volcanogenic rocks radioactivity and potassium content increase in accordance with the change in the type of secondary processes from albitization, digestion carbonatization to chloritization, the development of mixed-layer formations, peletization-illitization and to microclinization. In the same direction, the ratios of thorium to potassium, uranium to potassium decrease.
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