The first geologic map of the Pacific Ocean and the continents bordering it is the result of cooperation of the geologists from the USSR Ministry of Geology and the Academy of Sciences of the USSR. The map synthesizes geologic data obtained from many different countries. The principle used in map compilation is the determination of rock masses according to age and composition. The correlation of deposits of different ages will be shown in the Atlas of Biopaleogeographic Maps of the Pacific Superregion. In the Precambrian shield margins, local names are given. The map emphasizes the importance of Mesozoic and Cenozoic intrusive magmatism. The location of endogenic mineralization is connected with this magmatism.

Special attention is given to Cenozoic volcanic rocks. The following series are distinguished: alkaline and alkaline-earth, the series of high-aluminia basalts, calc-alkaline, tholeitic, and others. Various extrusive volcanic features are indicated by separate symbols. Radiometric age dates of oceanic basalts also are given.

The distribution of different recent complexes of sediments, clastic, argillaceous, and biogenic is shown in the ocean and marginal sea floors. The complexes, including admixture of volcanic material of different composition, have special symbols. In order to distinguish biogenic sediments, quantitative data on the most important sedimentary components (CaCO₃, amorphous SiO₂) were taken into consideration. Some sampled pre-Quaternary deposits (Cretaceous-Neogene) and young volcanic rocks in the ocean-bottom areas are included on the map. Deep-drilling data (Glomar Challenger, etc.) are shown as enlarged columns, in which color indicates the recovered rock ages. The distribution of manganese nodules is contoured, phosphorite outcrops (mostly pre-Quaternary) also a e shown.

The Pacific mobile belt and Pacific Ocean comprise a global mineralogenetic province. Thus, the Pacific ore belt, the Pacific sulfur-bearing belt, the Pacific oil-gas belt, and others are singled out. The geologic map, especially its new international publication, is intended to be the basis for predictional estimation of the Pacific region.

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