The regional geologic mapping carried out during the last years in the State of Sinaloa by geologists from the Instituto de Geologia de la UNAM brings new knowledge to the economic-geologic research of the state and provides help to the economic development of Mexico.

The five main groups of mineral deposits in the area may be divided, on the basis of their characteristics, as follows: (1) Hydrothermal (epithermal; cavity filling); (2) Metasomatic (contact metasomatism; acid igneous rocks-dissemination); (3) Contact metamorphic (contact metamorphism); (4) Magmatic or primary (dissemination in ultramafic or mafic rocks); and (5) Other (deposits by mechanical concentration in clastic formations; residual and alluvial).

The important ages for metallic concentration were Jurassic, Late Cretaceous, early, middle, and late Tertiary, and Pleistocene.

The present paper describes the relations between the lithologic units and structure and their relation to mineralization.

Most frequently mineralized are the volcanic rocks, chiefly those of intermediate composition. Similarly, other host rocks are the Albian-Cenomanian carbonate rocks. Mineralization is more abundant in andesites, even though carbonated host rocks have developed many mineral deposits in the area.

The mafic and ultramafic rocks show serpentinization at several localities and include nickel, platinum, and antimony minerals.

Clastic continental Tertiary formations contain radioactive minerals in the northern part of the state.

Recent residual deposits often contain gold-placer deposits; Paleozoic host rocks contain gold, silver, zinc, and lead mineralization.

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