Banhadao is a multiple intrusion of some 11 km2 intruding the Tres Corregos granitic complex.
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K-Ar on phonolite (whole rock) of Barra do Teixeira gave 72.9 Ma (Cordani and Hasui, 1968).
The Mata Preto complex is intruded into the Precambrian metasediments of the Acungui Group and Tres Corregos granites but shows little topographical expression.
Small phonolite plugs are found a few km north and northeast of Cerro Azul.
Tunas comprises four coalescing intrusions covering 25 km2 which are cut by three intrusions of volcanic breccia. Several phonolite dykes up to 200 m thick extend to the northeast and southwest.
An oval-shaped complex of about 1 km diameter. Olivine gabbro and phonolite are present but little information is available.