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Geologic units in Llano county, Texas

Valley Spring Gneiss (preCambrian (Proterozoic)) at surface, covers 26 % of this area

Valley Spring Gneiss

Town Mountain Granite (preCambrian (Proterozoic)) at surface, covers 23 % of this area

Town Mountain Granite

Packsaddle Schist (preCambrian (Proterozoic); Llano Series) at surface, covers 22 % of this area

Packsaddle Schist

Younger granitic intrusion (preCambrian (Proterozoic)) at surface, covers 8 % of this area

Younger granitic intrusion

Hickory Sandstone Member (Middle Cambrian) at surface, covers 8 % of this area

Hickory Sandstone Member

Wilberns Formation showing San Saba Member (Late Cambrian) at surface, covers 3 % of this area

Wilberns Formation showing San Saba Member

Wilberns Formation showing Point Peak, Morgan Creek Limestone, and Welge Sandstone Members, undivided (Late Cambrian) at surface, covers 3 % of this area

Wilberns Formation showing Point Peak, Morgan Creek Limestone, and Welge Sandstone Members, undivided

Riley Formation showing Lion Mountain Sandstone and Cap Mountain Limestone Members, undivided (Middle Cambrian) at surface, covers 2 % of this area

Riley Formation showing Lion Mountain Sandstone and Cap Mountain Limestone Members, undivided

Tanyard Formation (Early Ordovician) at surface, covers 2 % of this area

Tanyard Formation

Gorman Formation (Early Ordovician) at surface, covers 0.8 % of this area

Gorman Formation

Alluvium (Holocene) at surface, covers 0.7 % of this area

Alluvium

Honeycut Formation (Early Ordovician) at surface, covers 0.5 % of this area

Honeycut Formation

Red Mountain Gneiss (preCambrian (Proterozoic)) at surface, covers 0.3 % of this area

Red Mountain Gneiss

Marble Falls Limestone (Pennsylvanian; Morrow Series) at surface, covers 0.2 % of this area

Marble Falls Limestone

Quaternary deposit, undivided (Quaternary) at surface, covers 0.2 % of this area

Quaternary deposit, undivided

Mafic igneous rocks (preCambrian (Proterozoic)) at surface, covers 0.1 % of this area

Mafic igneous rocks

Smithwick Formation (Middle Pennsylvanian; Atoka Series) at surface, covers < 0.1 % of this area

Smithwick Formation

Big Branch Gneiss (preCambrian (Proterozoic)) at surface, covers < 0.1 % of this area

Big Branch Gneiss

Terrace deposits (Pleistocene and Holocene) at surface, covers < 0.1 % of this area

Terrace deposits

Lost Creek Gneiss (preCambrian (Proterozoic)) at surface, covers < 0.1 % of this area

Lost Creek Gneiss