086 



THE GEOLOGY OF MINNESOTA. 



Coteau des Prairies, 101. 

 Valley of Des Moines river, 495. 

 Elevations, 196. 

 Soil and timber, 4!)7. 

 Trees and shrubs, -tun. 

 Geological structure, 499. 

 Potsdam quartzyte, 499. 

 Drift and contour, 503. 

 Glacial stria;, 503. 



First and second terminal moraines, 505. 

 Medial moraine, 506. 

 Interglacial drainage, 507. 

 Drainage during the last glacial epoch, 508. 

 Boulders and pebbles, 509. 

 Modified drift, 510. 

 Wells, 510. 



Water of Heron lake analyzed, 512. 

 Travertine, 513. 

 Material resources, 513. 

 Water-powers, 513. 

 Building stone, 513. 

 Lime, 513; bricks, 514. 

 Peat, 514; analyses of peat ashes, 516. 

 Aboriginal mounds, 516. 



County geology, 205. [18, 432, 638-9, 



Cretaceous clay in hollows of Cambrian strata, 

 of Devonian strata, 353-4. 

 clays, analyses, 438. 



Cretaceous formations: Sank river valley, 104; 

 Houston county , 233; Fillmore, 280, 307-3 1 1 ; 

 Olmsted, 352-6; Dodge, 370, 374; Freeborn, 

 383-5; Steele, 398-9; Waseca, 410; Blue 

 Earth, 431-9, 451; Faribault, 459 ,460; Waton- 

 wan and Martin, 477; Pipestone and Rock, 

 535, 538; Brown and Redwood, 98, 568, 

 572-9; Yellow Medicine, Lyon and Lin- 

 coln, 598-600; near Big Stone lake, 619; 

 Marsh lake and Lac qui Parle, 625; Le 

 Sueur, 639. 



Cretaceous formations, chief source of the blue 

 till, 126, 374, 595, 599, 659. 

 extent in Minnesota, 579. 

 making the Coteau des Prairies, 598-9, 601. 

 Cretaceous lignitic beds, 383, 398, 568, 572, 



577-9, 599. See Liynile in drift. 

 Crinoidal remains, 79, 301. 

 Crystalline rocks, as building stones, 142. 

 Cupriferous series, 422, 500. 

 Curved glacial strise, 604. 

 Cyathopliyllum ceratites, 79. 

 Cyrtina, 360. 



Dakota Central railway, elevations, 593. 

 Dakota group, 308, 574, 576. [570. 



Decomposition of gneiss and granite, 75, 98, 

 Deer, 23, 30, 79. 



Des Moines river, drainage system, l.>5; inter 

 glacial drainage course, 507. 



Devonian formations, 84, 303, 357. 



Diallage, 103. 



Dikes, 500, 597. 



Diospyros primawa, 354. 



Dip of Cambrian rocks, 225, 252; Cretaceous 

 strata, 599; Eoz.oic rocks, 569,597,598; Pots- 

 dam qnart/.yte, 499, 502, 53s. 5 to 1. 



Dodge county, chapter on, 367. 

 Situation and area, 367. 

 Surface features, 367. 

 Natural drainage, 367. 

 Water-powers, 368. 

 Topography, 368. 

 Elevations, 369. 

 Timber, trees and shrubs, 369. 

 Geological structure, 370. 

 Shakopee limestone, 370. 

 St. Peter sandstone, 370. 

 Trenton limestone, 370. 

 Galena limestone, 371. 

 Drift, 374. 

 Bricks and lime, 375. 



Dolomites as building stones, 153. 



Dolomitic limestones, as building stones, 163. 



Dovre (seventh) moraine, 621. 



Drainage, 132-6. Also see reports of counties. 



Drainage, interglacial, 481. 507. 



Drainage, local, effect on soils, 129. 



Drain-tiles, 452. 



Drift: Houston county ,227-230; Winona, 260-3; 

 Fillmore, 311-318; Olmsted, 343-5; Mower, 

 362-5; Dodge, 374; Freeborn, 385-8; Steele, 

 397, 399-402; Waseca, 406, 411-413; Blue 

 Earth, 439-445; Faribault, 460-7; Watonwan 

 and Martin, 4 78 -488; Cottonwood and Jack- 

 son, 503-513; Murray and Nobles, 520-2, 

 526-531; Pipestone and Rock, 548-553; Brown 

 and Redwood, 580-6; Yellow Medicine, Lyon 

 and Lincoln, 595, 599, 600-610; Big Stone and 

 Lac qui Parle, 619-630; Le, Sueur, 639-615: 

 Rice, 658-671. 



Drift, contained in the ice-sheet, 440, 602, 604, 

 626, and exposed on it by melting, 604, 610, 

 662, 665, 668. 



distribution and characters, 1 16, 126, 4:i9. 

 of successive glacial epochs, 406, 484, 52S, 

 582,626,658.' |6.vs ". 



origin of material, 99, 126, 374, 595, 599. 

 soils and subsoils, 125-8, 351. 

 thickness, 116, .'{4:!, 363,3X5, 399, Ml, 439, 

 478, 505, 527, 528, 551, 580, 601, 620, 639, 659. 

 Also see ./>V>i/Wi ;*, Till, Modified drift, Mo* 

 raiwx, (Undid cjxw/is, Glacial xtria\ and 

 Jce-theet. 



