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Full text of "Geological map of Wisconsin, Iowa and Minnesota : exhibiting, also, the extension of the Iowa coal-field into Missouri, and its relation to the Illinois coal-field"

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TABLE OF COLORS . 

COLORS OF THE METAM ORPHIC ROCKS. 


tfamblendie, Jn/i/laeeous arid Silirious Slates,- alternating occasionally nitli 
bedded Traps. 

Alternations of Metamorphosed Schists, Slates and Sandstones, mth Volcanic 
tints, and other bedded Traps arid Porphyries. 




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Metamorphic Schists, Gneiss taut Gneiss oid Rocks. 


COLORS OF THE IGNEOUS ROCKS 


Granite and Sienite. 


Greenstone . 


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Trap Rocks . 

COLORS OF THE INTRUSIVE DIKES 

Greenstone and Basaltic Ridges and Dikes, traversing Granitic and Metamorphic 
Rocks. 

Granitic Uplifts and Intrusions in Metamorphic Rocics. 


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'mmmmmmm ::\ 

r.X arrow Bikes of Basalt mid Greens tone, traversing Metamorphic Rocics . 


Hikes of Felspar in Metamorphic and 2 rap Rocks. 


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HAMILTON GROUP 

OXO^DAGA LIME- 
STONE . 


OF NEW YORK. 



TABLE OF COLORS 

COLORS OF THE SUPERFICIAL SEDIMENTARY >SITS. 


COLORS AND SUPERPOSITION OF THE EOSSILIEEROUS STRATA. 

Formation of thePlotte , 
Cheyenne & M reait 
Hirers, & Fox Mills, 
Upper Missouri . 


Formation of F»6* 
South Western Iowa . 


YOREDALE SERIES / craation ofthe licudty 
OF YORKSHIRE. LOW- of the Dts Monies 
ER SCAR LIMESTONE. Rapids of the 

Mississippi. 


Formation of 
Cedar Wiley. 


CLINTON St NIAGARA 

GROUPuS: XOXD AGA Upper Magnesian 

LIMESTONE UN PART?) Limestone 

HUD S ON RrV. GROUP 

AND TRENTON 

LIMESTONE. 


of Iowa & Wisconsin 


OF WISCONSIN, 


MINNESOTA: 


Exhibiting, also, the extension of the Iowa Coal-field into Missouri, 

and its relation to the Illinois Coal-field. 

Constructed from observations bv the 

UNITED STATES GEOLOGICAL CORPS, 

Under instructions from the Secretary of the Treasury, 

BY DAVID DALE OWEN, M.D. 

Principal Geologist. 


Upper Sandstone of 
Minnesota & Wisconsin 

CALCIFER0US SAND r 9 

STONE OE NEWYORK. Lower Magnesian *'*" 

Limestone of Iowa 
atul JVisconsin 


Sandstone usually white 

and incoherent 
YMagnesian Limestone 
I with veins & segregations 
\of Chert and Quartx. 

Magnesian Limestone 
| widi OolitiolayersS green 
\p articles disseminated 


Middle, Northern and Northeastern Minnesota 

BY J.G.NORWOOD, M.D. 

Assistant Geologist. 


POTSDAM SANDSTONEJLower Sandstone 


of Wisconsin and 
Mitiuesota 


d 
C 


with intercalations of 
Magnesiiui I.im ex tone 
Soft fine Sandstones 
usually fine grained. 
Uppcrlrilohite beds, 
Fucoidal layers and 
Given Faith. 
Coarse lingnln Grits. 
Lower 'IHlobite Beds, 
■Jjitujulu tf-Obolus l-i\ en 

^ \Lnfeiior pebbly Beds 

Red Sandstone* of L . 

Superior^ 


The greater part of the Southern Shore of Lake Superior, in Wisconsin, 

BY COL. CHA? WHITTLESEY. 


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Engraved by W. Smith , Wash 1 }