The Paleozoic and Mesozoic Rocks; A Discussion to Accompany the Geologic Map of the United States GEOLOGICAL SURVEY PROFESSIONAL PAPER 9«3 The Paleozoic and Mesozoic Rocks; A Discussion to Accompany the Geologic Map of the United States By PHILIP B. KING and HELEN M. BEIKMAN GEOLOGICAL SURVEY PROFESSIONAL PAPER 903 UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1976 UNITED STATES DEPARTMENT OF THE INTERIOR JAMES G. WATT, Secretary GEOLOGICAL SURVEY Dallas L. Peck, Director First printing 1976 Second printing 1981 For sale by the Distribution Branch, U.S. Geological Survey, 604 South Pickett Street, Alexandria, VA 22304 CONTENTS Page Page Abstract _____________________ 1 Paleozoic plutonic rocks Continued Introduction _______________ 1 Lower Paleozoic granitic rocks (Pgi) ___________ 38 Cambrian _________________ 1 Middle Paleozoic granitic rocks (Pg2) ___________ 39 Marine stratified rocks ( ) 2 Upper Paleozoic granitic rocks (Pg3) __________________ 39 Eugeosynclinal deposits (- e) __________________________ 4 Paleozoic mafic intrusives (Pmi) __ _________________ 42 Ordovician and Cambrian___________-____________________ 7 Metamorphic complexes.-______________________ 42 Marine stratified rocks (O-G) ______-______----____-___ 7 Triassic and Permian _______________________ 42 Ordovician ________________________________________ 7 Eugeosynclinal deposits (r~fc) __________ _________ 42 Marine stratified rocks (O) __________________________ 7 Triassic ______________________________ 43 Eugeosynclinal deposits (Oe) __________________________ 9 Colorado Plateau __________ ______ _______________ 43 Silurian and Ordovician ___________________________ 10 Great Plains ____________________________ 46 Eugeosynclinal deposits (SOe) ____________________ 10 Appalachian Region _______________________ 46 Silurian __________________________________ 10 Jurassic and Triassic (J~fc) _______________________ __ 47 Marine stratified rocks (S) _______________________ 10 Jurassic _______________________________ _________ 47 Eugeosynclinal deposits (Se) ________________ 12 Rocky Mountain Region ______________________________ 47 Devonian and Silurian _____________________-___ 13 Pacific coastal area ____________________-___ 48 Marine stratified rocks (DS) _--____-_______-_-_--__--_-_ 13 Continental deposits(Jc) _____--___--_-_-____----_---__ 48 Eugeosynclinal deposits (DSe) ___________________ 13 Lower Mesozoic ____-________________________ 48 Devonian __________________________________________ 14 Marine stratified rocks (1 IVfe) ______________________ 48 Marine stratified rocks (D) ______________________ 14 Eugeosynclinal deposits (1 IVfe e) ______________________ 49 Continental deposits (D2c, Dac) ______________________ 16 Volcanic rocks (llVfev) __________________________________ 51 Eugeosynclinal deposits (De) ________________________ 16 Cretaceous ____________________________---______-__------__ 51 Lower Paleozoic _______________________________ 17 Lower Cretaceous _______________________ 51 Marine stratified rocks (IP) __________________________ 17 Texas ____________________________ 51 Cratonic deposits __________________________ 17 Atlantic Coastal Plain __________________ 54 Miogeosynclinal deposits _______________________ 20 Rocky Mountains _________________________ __ 55 Rocks of outlying areas ______________________________ 20 California and Oregon ______________________ 55 Eugeosynclinal deposits (IPe) ______________________ 21 Washington _________________________ 55 Mississippian ___________________________________ 22 Upper Cretaceous __---_____--______--____---_------__ 56 Pennsylvanian __________________________________________ 24 Western Gulf Coastal Plain ________________ 56 Permian _________________________________ 27 Eastern Gulf Coastal Plain _______________ 56 Appalachian Region __________________________ 28 Atlantic Coastal Plain _________________ 57 Southwestern United States__________________________ 28 Great Plains and Rocky Mountains __-______---__ 57 Midcontinent Region __________________________ 29 Pacific coastal area ____________________________ 59 New Mexico ________________________________ 32 Continental deposits (Kc) _______________________ 59 Northern Arizona ______________________________ 32 Eugeosynclinal deposits (Ke) _____-_______-__-___ 60 Cordilleran Region _____________________________ 33 Volcanic rocks (Kv)________________________ 60 Eugeosynclinal deposits (Pe) __________________________ 33 Upper Mesozoic -_-_---__________________ ________ 61 Upper Paleozoic ______-_-_--_--____-__________________ 33 Upper Mesozoic eugeosynclinal deposits (ul\^e) ______ 61 Marine stratified rocks (uP) __________________________ 33 Cretaceous eugeosynclinal deposits (Ke) ____________ 62 Mississippian ____________________________________ 33 Mesozoic plutonic and intrusive rocks _________.____ 62 Pennsylvanian ______________________________________ 36 Triassic granitic rocks (Tig) __________-__________ 62 Permian ___________________________________ 36 Triassic mafic intrusives (Td) __________________________ 63 Outlying miogeosynclinal rocks ________________ 37 Jurassic granitic rocks (Jg) ____________________ 63 Eugeosynclinal deposits (upe) ______________________ 37 Jurassic mafic intrusives (Jmi) ______________________ 68 Paleozoic plutonic rocks___________________________ 38 Cretaceous granitic rocks (Kg) __________________ 68 Cambrian granitic rocks (-Gg) ---_______-_____---___ 38 Cretaceous intrusive rocks (Ki) ____________________ 71 References cited ______________________________________ 72 ILLUSTRATIONS FIGURES 1-19. Maps of: Page 1. Eastern United States, showing areas mapped as Cambrian on Geologic Map of United States 3 2. New England, showing positions of tectonic features----__-_____________-___-____ 5 III IV CONTENTS FIGURES 1-19. Maps of Continued Pase 3. Eastern United States, showing areas mapped as Ordovician on Geologic Map of United States--_____ 8 4. Eastern United States, showing areas mapped as Silurian on Geologic Map of United States ____________ 11 5. Eastern United States, showing areas mapped as Devonian on Geologic Map of United States -_________ 15 6. Western United States, showing areas mapped as lower Paleozoic on Geologic Map of United States ______ 18 7. Eastern Cordilleran Region, showing surface and subsurface extent of lower Paleozoic on Geologic Map of United States _____________________________________________________ 19 8. Eastern United States, showing areas mapped as Mississippian on Geologic Map of United States ________ 23 9. Eastern United States, showing areas mapped as Pennsylvanian on Geologic Map of United States __-___ 26 10. United States, showing areas mapped as Permian on Geologic Map of United States-------_______--__-_ 30 11. Western United States, showing areas mapped as upper Paleozoic on Geologic Map of United States __ 34 12. Eastern part of Cordilleran Region, showing surface and subsurface extent of upper Paleozoic on Geologic Map of United States _________________________________________________ 35 13. United States, showing areas mapped as Paleozoic plutonic rocks on Geologic Map of United States ______ 40 14. United States, showing areas mapped as lower Mesozoic stratified rocks on Geologic Map of United States ____________________________________________________________ 44 15. United States, showing areas mapped as Cretaceous stratified rocks on Geologic Map of United States ____ 52 16. United States, showing areas mapped as Mesozoic and Cenozoic plutonic and intrusive rocks on Geologic Map of United States _______._.______________________________________________ 64 17. Western United States, showing areas of Triassic granitic rocks as mapped on Geologic Map of United States _______________________________________________________________ 66 18. Western United States, showing areas mapped as Jurassic granitic rocks and mafic intrusives on Geologic Map of United States ______________________________________________._______ 67 19. Western United States, showing areas mapped as Cretaceous grantitic rocks and Cretaceous intrusive rocks on Geologic Map of United States _________________ _________________________________ 69 THE PALEOZOIC AND MESOZOIC ROCKS; A DISCUSSION TO ACCOMPANY THE GEOLOGIC MAP OF THE UNITED STATES By PHILIP B. KING and HELEN M. BEIKMAN ABSTRACT stratigraphy for example, those of Dunbar (1969), This report deals with the Paleozoic and Mesozoic rocks that are Kay and Colbert (1965), and Kummel (1970). Correla­ exposed within the area covered by the Geologic Map of the United tion of the formations of the Paleozoic and Mesozoic States and treats them in terms of the map legend. They are there­ systems, with useful annotations, may be found in the fore discussed in chronological order, from oldest to youngest. Under charts prepared by committees of the National Re­ each age, the stratified rocks in the most complete sequences are described first, followed by combinations such as Devonian and Silu­ search Council that were published between 1940 and rian, Jurassic and Triassic, and finally by lower Paleozoic, upper 1960 by the Geological Society of America. In addition, Paleozoic, and lower Mesozoic. Next, special lithologic types of each some regional surveys are available, the most notable age are taken up, the continental deposits, eugeosynclinal deposits, of which is the Geologic Atlas of the Rocky Mountain and volcanic rocks. At the end of the discussions of both Paleozoic region (Mallory, 1972). and Mesozoic Eras are summaries of the plutonic