|Oligocene, Gulf Coast, Gulf of Mexico
The Frio Formation is one of the most mineralogically immature and reactive units in our study. Composition of anorthite (20 percent) and K-feldspar (30 percent) (Land and Macpherson, 1992) reflects high volcanic input into the sedimentary environment. This unit has high potential for reacting with high CO2 brine.
Land, L. S., and Macpherson, G. L., 1992, Origin of saline formation waters, Cenozoic section, Gulf of Mexico sedimentary basin: American Association of Petroleum Geologists Bulletin v. 76, p. 1344–1362.