Key: Mainly Marine Stratified Sequence
- Quaternary
- Qh Holocene
- Qp Pleistocene
- Q Quaternary
- Limits of Pleistocene glacial deposits
- Tertiary
- Tp Pliocene
- Tm Miocene
- To Oligocene
- Te3 Eocene Jackson Group
- Te2 Eocene Claihorne Group
- Te1 Eocene Wilcox Group
- Te Eocene
- Ts Paleocene
- Cretaceous
- uK4 Navarro Group
- uK3, uK3b, Uk3a Taylar Group
- uK2 Austin and Eagle Ford Group
- uK1 Woodhine and Tuscaloosa Groups
- uK Upper Cretaceous
- lK3 Washita Group
- lK2 Fredericksburg Group
- lK1 Trinity Group
- lK lower Cretaceous
- Triassic-Jurassic
- J Jurassic
- JTr Lower Jurassic and Upper Triassic
- Tr Triassic
- lMz lower Mesozoic
- Permian
- P4 Oehoan Series
- P3b Upper part of Guadalupian Series
- P3a Lower part of Guadalupian Series
- P3 Guadalupian Series
- P2b Upper part of Leonardian Series
- P2a Lower part of Leonardian Series
- P1 Wolfcampian Series
- P Permian
- Pennsylvanian
- PP4 Virgilian Series
- PP3 Missourian Series
- PP2 Des Moinesian Series
- PP1 Mulkan and Morrowan Series
- PP1a Arnkan and Morrowan Series, Jackson Sandstone
- uPz Upper Paleozoic clastic wedge sequence
- uPz Upper Paleozoic
- PP Pennsylvanian
- Mississippian
- M3 Chesterian Series
- M2 Merantecian Series
- M1 Osagean and Kinderkookian Series
- M Mississippian
- Devonian
- D3 Upper Devonian
- D2 Middle Devonian
- D1 Lower Devonian
- D Devonian
- Silurian
- S3 Upper Silurian (Cayugan)
- S2 Middle Silurian (Niagaran)
- S1 Lower Silurian (Alexandrian)
- DS Devonian and Silurian
- S Silurian
- Ordvician
- O3 Upper Ordovician (Cincinnatian)
- O2 Middle Ordovician (Mohawkian)
- O1, O1b, O1a Lower Ordovician (Canadian)
- O Ordovician
- lPz Lower Paleozoic
- OC Cambrian-Ordovician
- Cambrian
- C Cambrian
- Cq basal Lower Cambrian clastic rocks
- Precambrian
- Z Precambrian sedimentary rocks
- Y3 Missoula Group
- Y2 Wallace, Siyeh and Helena Formations
- Y1 Ravalli Group and Prichard Formation
- Y Precambrian metasemimentary rocks
- X Precambrian metasedimentary rocks
- W metasedimentary rocks