The most productive mineral resources, except fuel, in South Korea are gold, silver, lead, zinc, copper, tungsten, molybdenum, iron, fluorite, graphite, kaolin, talc, and pyrophyllite. These mineral deposits are related closely to the geologic settings and tectonic patterns of the peninsula.

South Korea is divided tectonically into four segments. The Kyonggi-Ryongnam massif is composed of Precambrian schists and gneisses and constitutes a base for the succeeding formations. The Okcheon geosynclinal zone in the Kyonggi-Ryongnam massif stretches from southwest to northeast diagonally across the peninsula in a direction known as the Sinian direction. Its northeastern part is composed primarily of Paleozoic to early Mesozoic sedimentary formations and the southwestern part of the late Precambrian Okcheon metamorphic series. The Kyongsang basin occupies the southeast and southwest of the peninsula and is

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made up of a thick series of Jurassic terrestrial sedimentary and andesitic rocks. A few small Tertiary basins are scattered in the eastern coastal area and in Cheju Island, and are composed of marine sedimentary and basaltic rocks.

Jurassic Daebo granites intrude the Kyonggi-Ryongnam massif and the Okcheon zone in the Sinian direction, whereas Late Cretaceous Bulkuksa granites are scattered randomly in the Kyongsang basin.

Most of the mineral deposits are related to the acidic intrusives and are classified chiefly as hypothermal to mesothermal vein and metasomatic replacement deposits, depending on the predominance of structural or lithologic control. In Precambrian terranes gold-silver, lead-zinc, tungsten, molybdenum, and fluorite are present as vein deposits, and tungsten and iron deposits as metasomatic replacements, except for the Precambrian iron formation, graphite, and talc.

In the Paleozoic terranes, gold-silver, lead-zinc, tungsten, and iron deposits are metasomatic-replacement type although some gold-silver deposits may be vein type. In the Mesozoic terranes, iron, copper and lead-zinc veins are common in the andesitic rocks and cherty slate, whereas pyrophyllite deposits are in acidic tuffs as a result of post-igneous activities.

These mineralized areas, except the Kyongsang basin, are grouped into belts trending subparallel with the Sinian direction and generally show a rough zoning defined by the general gradient of genetic temperatures. The metallogenic epochs of these deposits are classified into four stages: Precambrian, Paleozoic, Jurassic to Early Cretaceous, and Late Cretaceous to early Tertiary.

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