Latitic Intrusive Rocks

Dark-gray to greenish-gray laccoliths and sills of latite, latitic andesite, and quartz latite. Contains phenocrysts of andesine, oligoclase, biotite, hornblend, and sphene in a finely crystalline andesine-biotite-quartz groundmass.
State South Dakota
Name Latitic Intrusive Rocks
Geologic age Eocene to Paleocene
Lithologic constituents
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-latite (Dike or sill, Laccolith)
Igneous > Hypabyssal > Mafic-hypabyssal > Hypabyssal-andesite (Dike or sill, Laccolith)
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-quartz-latite (Dike or sill, Laccolith)

Martin, J.E., Sawyer, J.F., Fahrenbach, M.D., Tomhave, D.W., and Schulz, L.D., 2004, Geologic Map of South Dakota: South Dakota Geological Survey, GM 10, scale 1:500,000.

NGMDB product
Counties Lawrence - Meade